/* ---------- 2D 档案页：暗底 / 贴边旗帜卡 / 蓝图衬底 / 夸张比例 ---------- */

:root {
  --archive-bg: #05070d;
  --archive-ink: #eef3fb;
  --archive-ink-dim: #a9b8d0;
  --archive-ink-faint: #6f7f99;
  --archive-card: #f4f7fb;
  --archive-card-ink: #0b0f17;
  --archive-line: rgba(120, 160, 210, 0.22);
  --archive-red: #ff2d4d;
  --archive-blue: #2e9bff;
  --archive-cyan: #7fd4ff;
  --archive-gold: #c9a25f;
  --archive-shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
  --archive-shadow-lg: 0 30px 90px rgba(0, 0, 0, 0.55);
  --archive-font-en: "Audiowide", "Microsoft YaHei", sans-serif;
  --archive-font-cn: "Microsoft YaHei", "PingFang SC", sans-serif;
}

.unit-site {
  --archive-fold-height: 46px;
  --archive-fold-depth: 25.3px;
  position: relative;
  z-index: 70;
  min-height: 100vh;
  min-height: 100svh;
  background: var(--archive-bg);
  color: var(--archive-ink);
  isolation: isolate;
  /* 折线切口上方必须露出照片墙原色, 不能再叠上抬阴影把切口染暗 */
  box-shadow: none;
  /* clip 不像 hidden 会把 overflow-y 计算为 auto, 上沿文件夹折线才能露出 */
  overflow-x: clip;
}

html.is-document-mode .unit-site {
  /* 档案态整页透出星场(2026-09-27): 顶沿折线区与内容区都不再铺实底, 底色由 #nebula 承担 */
  background: none;
}

/* ---------- 档案态星场/星云/折跃层(2026-09-27, 用户反馈档案背景纯黑):
   与 opensource/tutorial 同一视觉语言——星云渐变垫底, 星场 canvas 浮在内容之下,
   chapter 改半透明让星场隐约透出; 3D 态整组 display:none 不耗电 ---------- */
#nebula {
  position: fixed;
  inset: -3%;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(1100px 700px at 82% -10%, rgba(46, 155, 255, 0.22), transparent 60%),
    radial-gradient(900px 600px at 5% 110%, rgba(255, 45, 77, 0.16), transparent 62%),
    radial-gradient(760px 560px at 52% 46%, rgba(127, 156, 245, 0.1), transparent 70%),
    var(--archive-bg);
}

#warp {
  position: fixed;
  inset: 0;
  z-index: 1;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

#flash {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: var(--archive-bg);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.5s ease 0.05s;
}

html:not(.is-document-mode) #warp,
html:not(.is-document-mode) #nebula {
  display: none;
}

html.is-document-mode .archive-chapter {
  /* 52% 透明让星场/星云真实透出(实底会把星云全埋掉), 卡片自有实底保可读性 */
  background: color-mix(in srgb, var(--archive-bg) 52%, transparent);
}

/* 跨站折跃: 抵达(os-warp-arrive)暗场瞬时盖住, JS 揭幕时按 transition 淡出;
   离场(body.os-warp-out)暗场收拢 */
html.os-warp-arrive #flash {
  opacity: 1;
  transition: none;
}

body.os-warp-out #flash {
  opacity: 1;
  transition: opacity 0.3s ease 0.12s;
}

.archive-wrap {
  position: relative;
  z-index: 2;
  width: min(1500px, 94vw);
  margin: 0 auto;
  padding: 10vh 0 20vh; /* 加大板块间距, 配合强吸附 */
}

.archive-chapter {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  padding: 8vh 0 14vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--archive-bg);
}

/* Folder headings share the open-source 46px single-outline fold.
   Explicit side modifiers keep the alternation independent of DOM adjacency. */
.archive-fold::after {
  content: "";
  position: absolute;
  left: 0;
  top: -1px;
  width: 100%;
  height: var(--archive-fold-height);
  z-index: 3;
  pointer-events: none;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
  clip-path: polygon(
    0 55%, 6% 55%, 8% 0, 26% 0, 29% 55%, 100% 55%,
    100% calc(55% + 2px), 29% calc(55% + 2px),
    26% 2px, 8% 2px, 6% calc(55% + 2px), 0 calc(55% + 2px)
  );
}

.archive-fold--right::after {
  clip-path: polygon(
    0 55%, 71% 55%, 74% 0, 92% 0, 94% 55%, 100% 55%,
    100% calc(55% + 2px), 94% calc(55% + 2px),
    92% 2px, 74% 2px, 71% calc(55% + 2px), 0 calc(55% + 2px)
  );
}

/* 章节标题 */
.archive-head {
  margin-bottom: 72px;
}

.archive-head__meta {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 24px;
}

.archive-head__chip {
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 3px;
  color: var(--archive-red);
  border: 1px solid var(--archive-line);
  padding: 8px 18px;
  border-radius: 99px;
  background: rgba(255, 45, 77, 0.08);
}

.archive-head__rule {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--archive-line), transparent);
  max-width: 220px;
}

.archive-head__tag {
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 3px;
  color: var(--archive-ink-faint);
}

.archive-head__title {
  font-family: var(--archive-font-en);
  font-size: clamp(64px, 9.5vw, 132px);
  font-weight: 400;
  line-height: 1;
  color: var(--archive-ink);
  margin-bottom: 16px;
  text-shadow:
    0 0 30px rgba(46, 155, 255, 0.35),
    0 0 80px rgba(46, 155, 255, 0.12);
}

.archive-head__cn {
  font-size: clamp(20px, 2.4vw, 30px);
  color: var(--archive-ink-dim);
}

/* ============ 00 HERO: 左侧贴屏幕边亮色大卡片 + 右侧图片渐隐 ============ */

.archive-hero {
  padding: 0;
  justify-content: stretch;
  background: transparent;
}

.archive-hero .archive-wrap {
  width: 100%;
  max-width: none;
  padding: 0;
}

.archive-hero__inner {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  background: var(--archive-card);
  clip-path: polygon(
    0 var(--archive-fold-depth),
    6% var(--archive-fold-depth),
    8% 0,
    26% 0,
    29% var(--archive-fold-depth),
    100% var(--archive-fold-depth),
    100% 100%,
    0 100%
  );
}

.archive-hero__copy {
  position: relative;
  z-index: 1;
  padding: clamp(56px, 8vh, 96px) clamp(32px, 4vw, 64px) clamp(56px, 8vh, 96px)
    clamp(28px, 4vw, 72px);
  color: var(--archive-card-ink);
  display: flex;
  flex-direction: column;
  justify-content: center;
  max-width: 760px;
}

.archive-eyebrow {
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 4px;
  color: var(--archive-red);
  margin-bottom: 24px;
}

.archive-hero__title {
  font-family: var(--archive-font-en);
  font-size: clamp(72px, 8.5vw, 148px);
  font-weight: 400;
  line-height: 0.95;
  color: var(--archive-card-ink);
  margin-bottom: 12px;
}

.archive-hero__cn {
  font-size: clamp(22px, 2.6vw, 34px);
  color: #5b6879;
  margin-bottom: 32px;
}

.archive-hero__lead {
  font-size: clamp(17px, 1.9vw, 22px);
  line-height: 1.95;
  color: #46536a;
  max-width: 560px;
  margin-bottom: 48px;
}

.archive-hero__lead b {
  color: var(--archive-card-ink);
  font-weight: 700;
}

.archive-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.archive-stat {
  --archive-stat-accent: #ff2d4d;
  --archive-stat-accent-rgb: 255, 45, 77;
  position: relative;
  isolation: isolate;
  overflow: hidden;
  min-height: 148px;
  padding: 27px 26px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background:
    linear-gradient(
      135deg,
      rgba(var(--archive-stat-accent-rgb), 0.11),
      transparent 44%
    ),
    linear-gradient(145deg, #101827 0%, #05070d 100%);
  border: 1px solid rgba(var(--archive-stat-accent-rgb), 0.3);
  border-radius: 15px;
  box-shadow:
    0 18px 42px rgba(5, 7, 13, 0.22),
    inset 0 1px 0 rgba(255, 255, 255, 0.05),
    inset 4px 0 0 rgba(var(--archive-stat-accent-rgb), 0.8);
  transition:
    transform 0.3s cubic-bezier(0.22, 1, 0.36, 1),
    border-color 0.3s ease,
    box-shadow 0.3s ease;
}

.archive-stat:nth-child(even) {
  --archive-stat-accent: #7fd4ff;
  --archive-stat-accent-rgb: 127, 212, 255;
}

.archive-stat::before {
  content: "";
  position: absolute;
  z-index: 0;
  top: 0;
  right: 0;
  left: 0;
  height: 2px;
  background: linear-gradient(
    90deg,
    var(--archive-stat-accent),
    rgba(var(--archive-stat-accent-rgb), 0.18) 64%,
    transparent
  );
}

.archive-stat::after {
  content: "";
  position: absolute;
  z-index: 0;
  top: 0;
  right: 0;
  width: 88px;
  height: 100%;
  background: repeating-linear-gradient(
    135deg,
    rgba(var(--archive-stat-accent-rgb), 0.1) 0 1px,
    transparent 1px 10px
  );
  mask-image: linear-gradient(90deg, transparent, #000);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000);
  pointer-events: none;
}

.archive-stat:hover {
  transform: translateY(-4px);
  border-color: rgba(var(--archive-stat-accent-rgb), 0.58);
  box-shadow:
    0 24px 54px rgba(var(--archive-stat-accent-rgb), 0.17),
    inset 0 1px 0 rgba(255, 255, 255, 0.08),
    inset 4px 0 0 var(--archive-stat-accent);
}

.archive-stat b {
  position: relative;
  z-index: 1;
  display: block;
  font-family: var(--archive-font-en);
  font-size: clamp(32px, 3.4vw, 48px);
  font-weight: 400;
  line-height: 1.05;
  color: var(--archive-stat-accent);
  margin-bottom: 18px;
  text-shadow: 0 0 24px rgba(var(--archive-stat-accent-rgb), 0.26);
}

.archive-stat b i {
  font-style: normal;
}

.archive-stat span {
  position: relative;
  z-index: 1;
  font-size: 14px;
  color: rgba(226, 236, 250, 0.78);
  line-height: 1.55;
}

.archive-hero__media {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
}

.archive-hero__media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* 左侧文字区压浅色罩，右侧保留照片细节 */
.archive-hero__media::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  background: linear-gradient(
    100deg,
    var(--archive-card) 0%,
    rgba(244, 247, 251, 0.92) 30%,
    rgba(244, 247, 251, 0.55) 52%,
    transparent 74%
  );
  pointer-events: none;
}

.archive-hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    0deg,
    rgba(5, 7, 13, 0.55) 0%,
    transparent 40%
  );
  pointer-events: none;
}

/* picture 仅作条件加载壳, 定位仍落在 img.archive-hero__logo 上 */
.archive-hero__media .archive-hero__logo-picture {
  display: contents;
}

/* 悬浮在右侧照片中央的队徽 */
.archive-hero__media .archive-hero__logo {
  position: absolute;
  z-index: 3;
  inset: 0 22% 0 auto;
  margin: auto 0;
  width: min(51%, 420px);
  height: auto;
  object-fit: contain;
  filter: drop-shadow(0 18px 42px rgba(0, 0, 0, 0.45));
  animation: archive-hero-logo-float 7s ease-in-out infinite;
  pointer-events: none;
}

@keyframes archive-hero-logo-float {
  0%,
  100% {
    transform: translateY(-10px);
  }
  50% {
    transform: translateY(10px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .archive-hero__media .archive-hero__logo {
    animation: none;
  }
}

.archive-scrollcue {
  position: absolute;
  bottom: 34px;
  left: 23vw;
  display: flex;
  align-items: center;
  gap: 14px;
  color: #8a95a5;
  font-family: var(--archive-font-en);
  font-size: 12px;
  letter-spacing: 3px;
  z-index: 5;
}

.archive-scrollcue__line {
  width: 56px;
  height: 1px;
  background: linear-gradient(90deg, var(--archive-red), transparent);
  animation: archive-scroll-pulse 2s ease-in-out infinite;
}

@keyframes archive-scroll-pulse {
  0%,
  100% {
    transform: scaleX(1);
    opacity: 0.6;
  }
  50% {
    transform: scaleX(0.6);
    opacity: 1;
  }
}

/* ============ 01 WHO WE ARE: 电路末端, 上下布局, 左右贴边旗帜卡 ============ */

.archive-circuit {
  width: 100vw;
  margin-left: calc(50% - 50vw);
  margin-top: 24px;
  display: flex;
  flex-direction: column;
}

.archive-circuit__row {
  position: relative;
  display: flex;
  padding: 26px 0;
}

.archive-circuit__row--left {
  justify-content: flex-start;
}

.archive-circuit__row--right {
  justify-content: flex-end;
}

/* 电路走线: 从旗帜尖端延伸到对面 */
.archive-circuit__row::after {
  content: "";
  position: absolute;
  top: 50%;
  height: 2px;
  width: 14vw;
  background: repeating-linear-gradient(
    90deg,
    rgba(201, 162, 95, 0.65) 0 10px,
    transparent 10px 18px
  );
  pointer-events: none;
}

.archive-circuit__row--left::after {
  left: calc(min(820px, 58vw) - 40px);
}

.archive-circuit__row--right::after {
  right: calc(min(820px, 58vw) - 40px);
}

/* 电路末端节点 */
.archive-circuit__row::before {
  content: "";
  position: absolute;
  top: 50%;
  width: 14px;
  height: 14px;
  margin-top: -7px;
  border-radius: 50%;
  border: 3px solid var(--archive-gold);
  background: var(--archive-bg);
  box-shadow: 0 0 16px rgba(201, 162, 95, 0.5);
  z-index: 2;
  pointer-events: none;
}

.archive-circuit__row--left::before {
  left: calc(min(820px, 58vw) + 12vw - 40px);
}

.archive-circuit__row--right::before {
  right: calc(min(820px, 58vw) + 12vw - 40px);
}

/* 旗帜卡: 贴屏幕边 + 燕尾 + 蓝图衬底 */
.archive-flag {
  position: relative;
  width: min(820px, 58vw);
  min-height: 320px;
  padding: 52px 96px 52px clamp(28px, 4vw, 72px);
  color: #f2f6ff;
  background-image:
    linear-gradient(
      100deg,
      rgba(5, 7, 13, 0.94) 0%,
      rgba(5, 7, 13, 0.78) 52%,
      rgba(5, 7, 13, 0.42) 100%
    ),
    var(--flag-img, none);
  background-size: cover;
  background-position: center;
  clip-path: polygon(
    0 0,
    calc(100% - 76px) 0,
    100% 50%,
    calc(100% - 76px) 100%,
    0 100%
  );
  display: flex;
  flex-direction: column;
  justify-content: center;
  box-shadow: var(--archive-shadow-lg);
  transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

.archive-circuit__row--right .archive-flag {
  padding: 52px 172px 52px 96px;
  text-align: right;
  align-items: flex-end;
  background-image:
    linear-gradient(
      260deg,
      rgba(5, 7, 13, 0.94) 0%,
      rgba(5, 7, 13, 0.78) 52%,
      rgba(5, 7, 13, 0.42) 100%
    ),
    var(--flag-img, none);
  clip-path: polygon(
    76px 0,
    100% 0,
    100% 100%,
    76px 100%,
    0 50%
  );
}

.archive-flag:hover {
  transform: scale(1.015);
}

.archive-flag__index {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--archive-gold);
  margin-bottom: 16px;
}

.archive-flag h3 {
  font-size: clamp(36px, 4.2vw, 58px);
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 12px;
  text-shadow: 0 2px 24px rgba(0, 0, 0, 0.6);
}

.archive-flag__en {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--archive-cyan);
  margin-bottom: 20px;
}

.archive-flag p {
  font-size: 16px;
  line-height: 1.9;
  color: rgba(226, 236, 250, 0.85);
  max-width: 520px;
}

/* ============ 影像 MEDIA：暗色板块 + 渐变过渡 ============ */

.archive-media {
  position: relative;
  /* 底部留白: 视频区与下一章拉开视觉间距 */
  padding: 0 0 16vh;
  background: var(--archive-bg);
  color: #eef3fb;
}

/* WHO WE ARE → 影像记录：从浅色主视觉过渡到暗色媒体区 */
.archive-media::before {
  content: "";
  display: block;
  height: clamp(90px, 14vh, 170px);
  background: linear-gradient(180deg, #f7f9fb 0%, rgba(244, 247, 251, 0.7) 28%, var(--archive-bg) 100%);
}

.archive-media__content {
  width: min(1500px, 94vw);
  margin: 0 auto;
}

/* 两段 reel 之间的间距 */
.archive-media__reel + .archive-media__reel {
  margin-top: clamp(28px, 4vh, 56px);
}

/* 暗色媒体区里的章节标题: 保留与原子标题相同的上间距 */
.archive-media .archive-head {
  margin-top: 12px;
}

/* 影像记录标题与 REEL 01 之间: 去掉 wrap 底部留白, 压缩首个 label 上间距 */
.archive-media .archive-wrap {
  padding-bottom: 0;
}

.archive-media__content > .archive-media__reel:first-child .archive-media__label {
  margin-top: 24px;
}

.archive-media__label {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
  margin: 48px 0 14px;
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: rgba(238, 243, 251, 0.5);
}

.archive-media__label b {
  color: var(--archive-red);
  font-size: 15px;
  letter-spacing: 2px;
}

/* Bilibili 官方播放器流式嵌入 */
.archive-media__player {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #000000;
}

.archive-media__feature {
  width: min(1120px, 100%);
  margin: 0 auto;
}

.archive-media__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(12px, 1.4vw, 22px);
}

.archive-media__grid .archive-media__player {
  max-height: none;
}

.archive-media__player iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

.video-facade {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  border: 0;
  padding: 0;
  color: #eef3fb;
  background:
    linear-gradient(180deg, rgba(5, 7, 13, 0.32), rgba(5, 7, 13, 0.78)),
    #05070d;
  cursor: pointer;
  font-family: var(--archive-font-en);
  text-align: center;
}

.video-facade[hidden] {
  display: none;
}

.video-facade__inner {
  display: grid;
  justify-items: center;
  gap: 8px;
  transform: translateY(0);
  transition: transform 180ms ease, opacity 180ms ease;
}

.video-facade__play {
  position: relative;
  display: block;
  width: 56px;
  height: 56px;
  border: 1px solid rgba(238, 243, 251, 0.56);
  border-radius: 999px;
  background: rgba(238, 243, 251, 0.08);
  box-shadow: 0 18px 54px rgba(0, 0, 0, 0.28);
}

.video-facade__play::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 53%;
  width: 0;
  height: 0;
  border-top: 10px solid transparent;
  border-bottom: 10px solid transparent;
  border-left: 15px solid currentColor;
  transform: translate(-50%, -50%);
}

.video-facade__text {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
}

.video-facade__hint {
  font-size: 11px;
  letter-spacing: 0;
  opacity: 0.58;
}

.video-facade:hover .video-facade__inner,
.video-facade:focus-visible .video-facade__inner {
  transform: translateY(-3px);
}

.video-facade:focus-visible {
  outline: 2px solid rgba(238, 243, 251, 0.72);
  outline-offset: -6px;
}

.archive-media__note {
  position: relative;
  z-index: 1;
  padding-top: 12px;
  font-size: 12px;
  color: rgba(238, 243, 251, 0.42);
}

.archive-media__note a {
  color: rgba(238, 243, 251, 0.62);
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (max-width: 900px) {
  .archive-media__grid {
    grid-template-columns: 1fr;
    width: min(680px, 100%);
    margin: 0 auto;
  }
}

/* ============ 横幅 ============ */

.archive-banner {
  position: relative;
  box-sizing: border-box;
  width: 100vw;
  margin-left: calc(50% - 50vw);
  min-height: 88vh;
  margin-top: 0;
  margin-bottom: 0;
  padding: 8vh 0;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: var(--archive-bg);
}

.archive-banner::before {
  content: "";
  position: absolute;
  top: 8vh;
  left: 0;
  width: 100%;
  height: 90px;
  z-index: 4;
  pointer-events: none;
  background: var(--archive-bg);
  clip-path: polygon(0 0, 0 45%, 68% 45%, 71% 100%, 89% 100%, 92% 45%, 100% 45%, 100% 0);
}

.archive-banner::after {
  content: "";
  position: absolute;
  bottom: 8vh;
  left: 0;
  width: 100%;
  height: 90px;
  z-index: 4;
  pointer-events: none;
  background: var(--archive-bg);
  clip-path: polygon(0 100%, 0 55%, 38% 55%, 41% 0, 59% 0, 62% 55%, 100% 55%, 100% 100%);
}

.archive-banner__bg {
  position: absolute;
  inset: 8vh -6%;
  width: 112%;
  height: calc(100% - 16vh);
  object-fit: cover;
  z-index: 0;
}

.archive-banner__overlay {
  position: absolute;
  inset: 8vh 0;
  background: linear-gradient(
    90deg,
    rgba(5, 7, 13, 0.88) 0%,
    rgba(5, 7, 13, 0.42) 50%,
    rgba(5, 7, 13, 0.78) 100%
  );
  z-index: 1;
}

.archive-banner__content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 90px 40px;
  color: #fff;
}

.archive-banner__quote {
  font-size: clamp(40px, 6.5vw, 84px);
  font-weight: 900;
  letter-spacing: 8px;
  line-height: 1.15;
  text-shadow: 0 2px 40px rgba(0, 0, 0, 0.7);
  margin-bottom: 26px;
}

.archive-banner__sub {
  display: inline-block;
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 4px;
  color: #fff;
  background: var(--archive-red);
  padding: 9px 24px;
  border-radius: 99px;
}

/* ============ 02 UNITS ============ */

.archive-grid {
  display: grid;
  gap: 24px;
}

.archive-grid--2 {
  grid-template-columns: repeat(2, 1fr);
}

.archive-card {
  position: relative;
  background: var(--archive-card);
  color: var(--archive-card-ink);
  border: 1px solid rgba(11, 15, 23, 0.06);
  border-radius: 24px;
  padding: 44px 38px;
  box-shadow: var(--archive-shadow);
  transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1),
    box-shadow 0.35s ease;
  overflow: hidden;
}

.archive-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 7px;
  height: 100%;
  background: linear-gradient(180deg, var(--archive-red), var(--archive-blue));
}

.archive-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--archive-shadow-lg);
}

.archive-card__index {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: #8a95a5;
  display: block;
  margin-bottom: 16px;
}

.archive-card h3 {
  font-size: clamp(30px, 3.2vw, 42px);
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--archive-card-ink);
}

.archive-card__en {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 2px;
  color: #0e7fbd;
  display: block;
  margin-bottom: 20px;
}

.archive-card p {
  font-size: 16px;
  line-height: 1.9;
  color: #46536a;
}

.archive-card--unit::before {
  background: linear-gradient(180deg, var(--archive-red), var(--archive-blue));
}

/* 子标题 */
.archive-sub {
  display: flex;
  align-items: center;
  gap: 20px;
  margin: 84px 0 40px;
}

.archive-sub__chip {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--archive-ink-faint);
  border: 1px solid var(--archive-line);
  padding: 7px 16px;
  border-radius: 99px;
  background: rgba(255, 255, 255, 0.02);
}

.archive-sub__title {
  font-size: clamp(28px, 3.4vw, 44px);
  font-weight: 700;
  color: var(--archive-ink);
}

/* 横向图片 + 文字一体框, 斜切透明过渡 */
.archive-media-row {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  margin: 72px 0;
  border-radius: 0;
  overflow: hidden;
  background: var(--archive-card);
  color: var(--archive-card-ink);
  box-shadow: var(--archive-shadow-lg);
  min-height: 480px;
  width: 100vw;
  margin-left: calc(50% - 50vw);
}

.archive-media-row__visual {
  position: relative;
  min-height: 480px;
  overflow: hidden;
}

.archive-media-row__visual img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}

.archive-media-row:hover .archive-media-row__visual img {
  transform: scale(1.05);
}

/* 斜向透明过渡衔接图片与文字区 */
.archive-media-row__visual::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    100deg,
    transparent 0%,
    transparent 55%,
    rgba(244, 247, 251, 0.75) 82%,
    var(--archive-card) 96%
  );
  pointer-events: none;
}

.archive-media-row__body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 56px 172px 56px clamp(32px, 5vw, 84px);
  position: relative;
  z-index: 2;
  background: var(--archive-card);
}

.archive-media-row__index {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
  color: #8a95a5;
  margin-bottom: 16px;
}

.archive-media-row__title {
  font-size: clamp(40px, 4.6vw, 64px);
  font-weight: 800;
  color: var(--archive-card-ink);
  margin-bottom: 14px;
}

.archive-media-row__en {
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 3px;
  color: #0e7fbd;
  margin-bottom: 26px;
}

.archive-media-row__desc {
  font-size: 17px;
  line-height: 1.95;
  color: #46536a;
}

.archive-media-row__note {
  margin-top: 20px;
  font-size: 13px;
  line-height: 1.8;
  color: #8a95a5;
}

/* ============ 03 JOIN: 部门纵向大卡片 ============ */

.archive-depts {
  display: flex;
  flex-direction: column;
  gap: 32px;
  margin: 56px 0 72px;
}

.archive-dept {
  position: relative;
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 40px;
  align-items: center;
  padding: 48px 52px;
  background-color: #05070d;
  background-image:
    linear-gradient(
      100deg,
      rgba(5, 7, 13, 0.94) 0%,
      rgba(5, 7, 13, 0.78) 52%,
      rgba(5, 7, 13, 0.52) 100%
    ),
    var(--dept-img, none);
  background-size: cover;
  background-position: center;
  color: #f2f6ff;
  border-radius: 0;
  box-shadow: var(--archive-shadow);
  overflow: hidden;
  transition: transform 0.35s ease, box-shadow 0.35s ease, background-image 0.35s ease;
  clip-path: polygon(0 0, calc(100% - 56px) 0, 100% 100%, 0 100%);
}

.archive-dept::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 7px;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
}

.archive-dept:hover {
  transform: translateX(14px);
  box-shadow: var(--archive-shadow-lg);
  background-image:
    linear-gradient(
      100deg,
      rgba(5, 7, 13, 0.9) 0%,
      rgba(5, 7, 13, 0.68) 52%,
      rgba(5, 7, 13, 0.42) 100%
    ),
    var(--dept-img, none);
}

.archive-dept__num {
  font-family: var(--archive-font-en);
  font-size: clamp(72px, 7vw, 120px);
  font-weight: 400;
  color: var(--archive-red);
  line-height: 1;
}

.archive-dept__body h3 {
  font-size: clamp(36px, 4vw, 56px);
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 10px;
  text-shadow: 0 2px 24px rgba(0, 0, 0, 0.6);
}

.archive-dept__body .archive-dept__en {
  font-family: var(--archive-font-en);
  font-size: 14px;
  letter-spacing: 3px;
  color: #0e7fbd;
  display: block;
  margin-bottom: 20px;
}

.archive-dept__body p {
  font-size: 17px;
  line-height: 1.9;
  color: rgba(226, 236, 250, 0.88);
  margin-bottom: 10px;
}

.archive-dept__body .archive-dept__req {
  font-size: 14px;
  color: rgba(226, 236, 250, 0.7);
  font-style: italic;
}

/* 获得 / 需要 —— 白字悬浮于黑底, 横屏细线分区 */
.archive-duo {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin: 56px 0;
}

.archive-duo__col {
  padding: 8px 56px 8px 0;
}

.archive-duo__col + .archive-duo__col {
  border-left: 1px solid var(--archive-line);
  padding: 8px 0 8px 56px;
}

.archive-duo .archive-sub {
  margin: 0 0 30px;
}

.archive-list {
  list-style: none;
  display: grid;
  gap: 16px;
  margin-top: 8px;
}

.archive-list li {
  position: relative;
  padding-left: 30px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--archive-ink-dim);
}

.archive-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--archive-red);
  box-shadow: 0 0 10px rgba(255, 45, 77, 0.55);
}

.archive-list--need li::before {
  background: var(--archive-blue);
  box-shadow: 0 0 10px rgba(46, 155, 255, 0.55);
}

/* ============ 03 JOIN: 舰载科技面板 (移植自 RM2027 招新页) ============ */

.archive-tech {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  margin: 56px 0 40px;
}

.archive-tech__panel {
  position: relative;
  background: rgba(120, 160, 210, 0.05);
  border: 1px solid var(--archive-line);
  box-shadow: var(--archive-shadow);
  overflow: hidden;
  transition: transform 0.35s ease, box-shadow 0.35s ease;
}

.archive-tech__panel:hover {
  transform: translateY(-6px);
  box-shadow: var(--archive-shadow-lg);
}

.archive-tech__head {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--pc, var(--archive-cyan));
  color: #04121a;
  padding: 9px 20px;
  font-family: var(--archive-font-en);
  font-size: 12px;
  letter-spacing: 2px;
}

.archive-tech__cap {
  margin-left: auto;
  background: rgba(4, 6, 14, 0.25);
  border-radius: 99px;
  padding: 2px 12px;
  font-size: 10px;
  letter-spacing: 2px;
  white-space: nowrap;
}

.archive-tech__body {
  padding: 22px 26px 24px;
}

.archive-tech__body p {
  font-size: 15px;
  line-height: 1.9;
  color: var(--archive-ink-dim);
}

.archive-tech__body p b {
  color: var(--archive-cyan);
  font-weight: 700;
}

.archive-tech__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.archive-tech__tags span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--archive-font-en);
  font-size: 10px;
  letter-spacing: 1.5px;
  color: var(--archive-cyan);
  border: 1px solid rgba(127, 212, 255, 0.32);
  background: rgba(127, 212, 255, 0.06);
  padding: 3px 10px;
}

.archive-tech__tags span::before {
  content: "";
  width: 5px;
  height: 5px;
  background: var(--pc, var(--archive-cyan));
  flex: none;
}

.archive-tech__readout {
  margin-top: 16px;
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 1.5px;
  color: var(--archive-cyan);
}

.archive-tech__readout b {
  color: var(--archive-gold);
  font-weight: 400;
}

.archive-tech__figure {
  background: rgba(120, 160, 210, 0.05);
  border: 1px solid var(--archive-line);
  border-left: 4px solid var(--archive-cyan);
  padding: 28px 32px 30px;
  box-shadow: var(--archive-shadow);
}

.archive-tech__figure h4 {
  font-size: 22px;
  font-weight: 800;
  color: var(--archive-cyan);
  margin-bottom: 18px;
}

.archive-tech__figure img {
  display: block;
  width: 100%;
  border: 1px solid var(--archive-line);
}

.archive-tech__note {
  margin-top: 16px;
  font-size: 13px;
  line-height: 1.8;
  color: var(--archive-ink-faint);
}

/* ============ 03 JOIN: 开源墙 ============ */

.archive-lead {
  max-width: 840px;
  margin: -12px 0 44px;
  font-size: 17px;
  line-height: 1.95;
  color: var(--archive-ink-dim);
}

.archive-repos {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.archive-repo {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 18px 22px;
  background: rgba(120, 160, 210, 0.05);
  border: 1px solid var(--archive-line);
  border-left: 4px solid var(--archive-blue);
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.archive-repo:hover {
  transform: translateX(8px);
  border-color: rgba(127, 212, 255, 0.5);
  border-left-color: var(--archive-cyan);
  text-decoration: none;
}

.archive-repo__name {
  display: block;
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 1px;
  color: var(--archive-ink);
  margin-bottom: 6px;
}

.archive-repo__desc {
  display: block;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--archive-ink-dim);
}

.archive-repo__star {
  font-family: var(--archive-font-en);
  font-size: 13px;
  color: var(--archive-gold);
  white-space: nowrap;
}

.archive-note a {
  color: rgba(238, 243, 251, 0.62);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.archive-faq__answer a {
  color: var(--archive-red);
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ============ 03 JOIN: 招新检索卡 + 资料下载 ============ */

.archive-recruit {
  position: relative;
  margin: 8px 0 28px;
  padding: clamp(28px, 4vw, 42px);
  border: 1px solid var(--archive-line);
  border-radius: 22px;
  background:
    linear-gradient(135deg, rgba(255, 45, 77, 0.1), transparent 42%),
    linear-gradient(160deg, rgba(46, 155, 255, 0.08), rgba(5, 7, 13, 0.92) 58%);
  box-shadow: var(--archive-shadow);
  overflow: hidden;
}

.archive-recruit::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 4px;
  background: linear-gradient(180deg, var(--archive-red), var(--archive-blue));
}

.archive-recruit__eyebrow {
  font-family: var(--archive-font-en);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--archive-red);
  margin-bottom: 14px;
}

.archive-recruit__title {
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 800;
  line-height: 1.15;
  color: var(--archive-ink);
  margin-bottom: 16px;
}

.archive-recruit__lead,
.archive-recruit__note {
  max-width: 52rem;
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.9;
  color: var(--archive-ink-dim);
}

.archive-recruit__note {
  margin-top: 12px;
  color: var(--archive-ink-faint);
}

.archive-recruit__links {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 28px 0 22px;
  padding: 0;
}

.archive-recruit__link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 92px;
  padding: 18px 20px;
  border: 1px solid rgba(120, 160, 210, 0.28);
  border-radius: 16px;
  background: rgba(7, 11, 20, 0.55);
  color: var(--archive-ink);
  text-decoration: none;
  transition:
    transform 0.28s ease,
    border-color 0.28s ease,
    box-shadow 0.28s ease,
    background 0.28s ease;
}

.archive-recruit__link:hover {
  transform: translateY(-3px);
  border-color: rgba(255, 45, 77, 0.55);
  background: rgba(255, 45, 77, 0.1);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.28);
}

.archive-recruit__link--primary {
  border-color: rgba(255, 45, 77, 0.55);
  background:
    linear-gradient(135deg, rgba(255, 45, 77, 0.22), rgba(46, 155, 255, 0.08));
}

.archive-recruit__link-en {
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--archive-cyan);
}

.archive-recruit__link-cn {
  font-size: 18px;
  font-weight: 700;
}

.archive-recruit__wechat {
  font-size: 14px;
  line-height: 1.7;
  color: var(--archive-ink-faint);
}

.archive-recruit__wechat b {
  color: var(--archive-ink);
}

.archive-downloads {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin: 8px 0 72px;
}

/* 资料下载离 RETURN 太近会被下一页 always 吸走; 加一屏余量, 小标题可以停住看完 */
#archive-join .archive-wrap {
  padding-bottom: 28vh;
}

.archive-download {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-height: 168px;
  padding: 26px 24px 24px;
  border: 1px solid var(--archive-line);
  border-radius: 18px;
  background:
    linear-gradient(160deg, rgba(46, 155, 255, 0.08), transparent 46%),
    rgba(10, 14, 24, 0.88);
  color: var(--archive-ink);
  text-decoration: none;
  box-shadow: var(--archive-shadow);
  transition:
    transform 0.3s ease,
    border-color 0.3s ease,
    box-shadow 0.3s ease;
  overflow: hidden;
}

.archive-download::after {
  content: "↓";
  position: absolute;
  top: 18px;
  right: 18px;
  font-size: 18px;
  color: var(--archive-cyan);
  opacity: 0.8;
}

.archive-download:hover {
  transform: translateY(-5px);
  border-color: rgba(127, 212, 255, 0.5);
  box-shadow: var(--archive-shadow-lg);
}

.archive-download__en {
  font-family: var(--archive-font-en);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--archive-cyan);
}

.archive-download__cn {
  font-size: clamp(20px, 2.2vw, 26px);
  font-weight: 800;
  line-height: 1.2;
}

.archive-download__hint {
  margin-top: auto;
  font-size: 13px;
  line-height: 1.6;
  color: var(--archive-ink-faint);
}

@media (max-width: 980px) {
  .archive-recruit__links,
  .archive-downloads {
    grid-template-columns: 1fr;
  }
}

/* ============ 03 JOIN: 新生培训卡片 ============ */

.archive-training {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin: 56px 0 40px;
}

.archive-training__card {
  position: relative;
  background: rgba(120, 160, 210, 0.05);
  border: 1px solid var(--archive-line);
  border-top: 4px solid var(--pc, var(--archive-cyan));
  padding: 30px 30px 32px;
  box-shadow: var(--archive-shadow);
  transition: transform 0.35s ease, box-shadow 0.35s ease;
}

.archive-training__card:hover {
  transform: translateY(-6px);
  box-shadow: var(--archive-shadow-lg);
}

.archive-training__en {
  display: block;
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 2.5px;
  color: var(--pc, var(--archive-cyan));
  margin-bottom: 14px;
}

.archive-training__card h4 {
  font-size: 26px;
  font-weight: 800;
  color: var(--archive-ink);
  margin-bottom: 12px;
}

.archive-training__card p {
  font-size: 15px;
  line-height: 1.9;
  color: var(--archive-ink-dim);
}

/* ============ FAQ 对话框 ============ */

.archive-faq {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 26px;
  margin: 48px 0 64px;
}

.archive-faq__item {
  position: relative;
  width: fit-content;
  max-width: min(760px, 100%);
  background: var(--archive-card);
  color: var(--archive-card-ink);
  border: 1px solid rgba(11, 15, 23, 0.06);
  border-radius: 28px;
  padding: 34px 42px;
  box-shadow: var(--archive-shadow);
  cursor: pointer;
  transition: box-shadow 0.3s ease, transform 0.3s ease;
}

.archive-faq__item::before {
  content: "";
  position: absolute;
  left: 38px;
  bottom: -9px;
  width: 22px;
  height: 22px;
  background: var(--archive-card);
  border-right: 1px solid rgba(11, 15, 23, 0.06);
  border-bottom: 1px solid rgba(11, 15, 23, 0.06);
  transform: rotate(45deg);
}

/* 偶数气泡靠右, 小尾巴换到右侧, 形成对话感 */
.archive-faq__item:nth-child(even) {
  align-self: flex-end;
}

.archive-faq__item:nth-child(even)::before {
  left: auto;
  right: 38px;
}

.archive-faq__item:hover {
  box-shadow: var(--archive-shadow-lg);
  transform: translateY(-3px);
}

.archive-faq__item.is-open .archive-faq__answer {
  max-height: 320px;
  opacity: 1;
  transform: translateY(0);
  margin-top: 20px;
}

.archive-faq__item.is-open .archive-faq__icon {
  transform: rotate(45deg);
}

.archive-faq__question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  font-size: clamp(20px, 2.2vw, 27px);
  font-weight: 700;
}

.archive-faq__icon {
  flex: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--archive-red), var(--archive-blue));
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 26px;
  line-height: 1;
  transition: transform 0.35s ease;
}

.archive-faq__answer {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transform: translateY(-10px);
  transition: max-height 0.45s ease, opacity 0.35s ease, transform 0.35s ease,
    margin-top 0.35s ease;
  font-size: 16px;
  line-height: 1.9;
  color: #46536a;
  padding-right: 56px;
}

.archive-faq__answer::before {
  content: "";
  display: block;
  width: 52px;
  height: 2px;
  background: var(--archive-red);
  margin-bottom: 16px;
}

/* ============ 入队航线: 横向时间线 + 旗帜节点 ============ */

.archive-steps {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  list-style: none;
  margin: 64px 0;
}

.archive-steps li {
  position: relative;
}

/* 航线分段: 每站从自己节点中心 (x=7, y=64) 连到下一站节点中心 (gap=40) */
.archive-steps li::before {
  content: "";
  position: absolute;
  top: 64px;
  left: 7px;
  right: -47px;
  height: 1px;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
  opacity: 0.45;
  pointer-events: none;
}

/* 每行末站不再向右延伸 */
.archive-steps li:nth-child(3n)::before {
  display: none;
}

.archive-steps__mast {
  position: relative;
  display: block;
  height: 70px;
  margin-bottom: 26px;
}

.archive-steps__flag {
  position: absolute;
  top: 0;
  left: 7px;
  display: inline-flex;
  align-items: center;
  height: 34px;
  padding: 0 22px 0 14px;
  font-family: var(--archive-font-en);
  font-size: 15px;
  letter-spacing: 2px;
  color: #fff;
  background: linear-gradient(135deg, var(--archive-red), #a3122c);
  clip-path: polygon(0 0, 100% 0, calc(100% - 11px) 50%, 100% 100%, 0 100%);
  transition: transform 0.3s ease;
}

.archive-steps__pole {
  position: absolute;
  left: 6px;
  top: 2px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(
    180deg,
    var(--archive-ink-faint),
    rgba(111, 127, 153, 0.25)
  );
}

.archive-steps__node {
  position: absolute;
  left: 1px;
  bottom: 0;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--archive-bg);
  border: 2px solid var(--archive-red);
  box-shadow: 0 0 12px rgba(255, 45, 77, 0.55);
  transition: box-shadow 0.3s ease, transform 0.3s ease;
}

.archive-steps li:nth-child(even) .archive-steps__flag {
  background: linear-gradient(135deg, var(--archive-blue), #1456a0);
}

.archive-steps li:nth-child(even) .archive-steps__node {
  border-color: var(--archive-blue);
  box-shadow: 0 0 12px rgba(46, 155, 255, 0.55);
}

.archive-steps li:hover .archive-steps__flag {
  transform: translateX(5px);
}

.archive-steps li:hover .archive-steps__node {
  transform: scale(1.25);
}

.archive-steps__time {
  display: block;
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--archive-gold);
  margin-bottom: 10px;
}

.archive-steps h4 {
  font-size: clamp(20px, 2vw, 26px);
  font-weight: 700;
  color: var(--archive-ink);
  margin-bottom: 12px;
}

.archive-steps p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--archive-ink-dim);
}

/* ============ 兵种图文揭示 (GIF 嵌入大字, 滚动 scrub 展开) ============ */

.unit-reveal {
  position: relative;
  margin: 0 0 88px;
  padding: 2vh 0;
}

.unit-reveal__eyebrow {
  margin-bottom: 48px;
  text-align: center;
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 4px;
  color: var(--archive-ink-faint);
}

.unit-reveal__lines {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: clamp(10px, 2vh, 22px);
}

.unit-reveal__line {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(12px, 2.4vw, 34px);
  width: 100%;
}

.unit-reveal__text {
  font-family: var(--archive-font-cn);
  font-size: clamp(40px, 9vw, 132px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: 0.04em;
  color: var(--archive-ink);
  white-space: nowrap;
  text-shadow: 0 0 34px rgba(46, 155, 255, 0.14);
}

.unit-reveal__text--en {
  font-family: var(--archive-font-en);
  font-size: clamp(28px, 6.6vw, 96px);
  font-weight: 400;
  letter-spacing: 0.1em;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: none;
}

/* 内嵌 GIF: 宽度由 JS 按滚动进度驱动 (--p: 0→1), 裁切式展开 */
.unit-reveal__media {
  --p: 0;
  flex: none;
  height: clamp(58px, 9.3vw, 144px);
  width: calc(var(--p) * clamp(100px, 19vw, 290px));
  overflow: hidden;
  border-radius: 10px;
  border: 1px solid var(--archive-line);
  background: rgba(127, 212, 255, 0.05);
  box-shadow: inset 0 0 26px rgba(0, 0, 0, 0.45);
}

.unit-reveal__media img {
  display: block;
  width: clamp(100px, 19vw, 290px);
  height: 100%;
  object-fit: cover;
}

/* 悬停跟随大图 (仅 hover 设备启用) */
.unit-reveal__follower {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 95;
  width: min(420px, 60vw);
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border-radius: 14px;
  border: 1px solid var(--archive-line);
  background: var(--archive-bg);
  box-shadow: var(--archive-shadow-lg);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.28s ease;
}

.unit-reveal__follower.is-on {
  opacity: 1;
}

.unit-reveal__follower img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (prefers-reduced-motion: reduce) {
  .unit-reveal__media {
    --p: 1;
  }

  .unit-reveal__follower {
    display: none;
  }

  .archive-return__ghost {
    opacity: 1;
  }
}

/* ============ 04 RETURN ============ */

/* 整页一屏: section 自己撑满视口高度 */
.archive-return.archive-chapter {
  box-sizing: border-box;
  min-height: 100vh;
  min-height: 100svh;
  height: 100vh;
  height: 100svh;
  max-height: 100svh;
  padding: 0;
  overflow: visible;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: stretch;
}

/* The return photo keeps its soft fade without a folder edge above it. */

.archive-return__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 38%;
  opacity: 0.24;
  pointer-events: none;
  user-select: none;
}

.archive-return__fade {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(
    180deg,
    var(--archive-bg) 0%,
    rgba(5, 7, 13, 0.82) 9%,
    rgba(5, 7, 13, 0.45) 26%,
    rgba(5, 7, 13, 0.38) 58%,
    rgba(5, 7, 13, 0.72) 88%,
    var(--archive-bg) 100%
  );
}

/* 两侧半透明中文大字: 滚动时向外扩散显现 (JS 驱动 --ghost-p) */
.archive-return__ghost {
  position: absolute;
  top: 26%;
  z-index: 2;
  font-family: var(--archive-font-cn);
  font-size: clamp(96px, 17vw, 300px);
  font-weight: 900;
  line-height: 1;
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
  opacity: 0;
  color: rgba(255, 45, 77, 0.1);
  -webkit-text-stroke: 1px rgba(255, 45, 77, 0.24);
}

.archive-return__ghost--left {
  left: 1.5vw;
}

.archive-return__ghost--right {
  right: 1.5vw;
  color: rgba(46, 155, 255, 0.1);
  -webkit-text-stroke: 1px rgba(46, 155, 255, 0.24);
}

/* 窄屏: 缩小并减淡, 避免遮挡正文 */
@media (max-width: 768px) {
  .archive-return__ghost {
    top: 24%;
    font-size: clamp(64px, 21vw, 120px);
    color: rgba(255, 45, 77, 0.07);
    -webkit-text-stroke: 1px rgba(255, 45, 77, 0.15);
  }

  .archive-return__ghost--right {
    color: rgba(46, 155, 255, 0.07);
    -webkit-text-stroke: 1px rgba(46, 155, 255, 0.15);
  }
}

/* archive-wrap 内容组在一屏 section 里垂直居中, 视觉上整块落在屏幕上下中间 */
.archive-return__inner.archive-wrap {
  position: relative;
  z-index: 2;
  box-sizing: border-box;
  width: min(1500px, 94vw);
  margin: 0 auto;
  min-height: 0;
  padding-top: 0;
  padding-bottom: 0;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.archive-return__title {
  font-family: var(--archive-font-en);
  font-size: clamp(56px, 8.5vw, 128px);
  font-weight: 400;
  line-height: 1;
  color: var(--archive-ink);
  margin-bottom: 26px;
  text-shadow:
    0 0 30px rgba(46, 155, 255, 0.35),
    0 0 80px rgba(46, 155, 255, 0.12);
}

.archive-return__cn {
  font-size: clamp(18px, 2.1vw, 24px);
  line-height: 1.95;
  color: var(--archive-ink-dim);
  max-width: 680px;
  margin-bottom: 48px;
}

.archive-return__cn b {
  color: var(--archive-ink);
}

.archive-return__btn {
  position: relative;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding: 26px 64px;
  border: none;
  border-radius: 99px;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
  color: #fff;
  cursor: pointer;
  box-shadow: 0 18px 56px rgba(255, 45, 77, 0.4);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.archive-return__btn:hover {
  transform: translateY(-4px) scale(1.03);
  box-shadow: 0 26px 80px rgba(255, 45, 77, 0.5);
}

.archive-return__btn-cn {
  font-size: 22px;
  font-weight: 700;
}

.archive-return__btn-en {
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 3px;
}

.archive-return__hint {
  margin-top: 30px;
  font-size: 15px;
  color: var(--archive-ink-faint);
}

/* 开源档案库入口: 斜切 HUD 次按钮, 与 open-source 页同款 */
.archive-return__os {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  margin-top: 26px;
  padding: 13px 26px;
  border: 1px solid rgba(46, 155, 255, 0.45);
  background: rgba(46, 155, 255, 0.06);
  color: var(--archive-cyan);
  text-decoration: none;
  transform: skewX(-16deg);
  transition: transform 0.25s ease, border-color 0.25s ease, background 0.25s ease;
}

.archive-return__os > * {
  transform: skewX(16deg);
}

.archive-return__os:hover {
  transform: translateY(-2px) skewX(-16deg);
  border-color: var(--archive-red);
  background: rgba(255, 45, 77, 0.08);
}

.archive-return__os-cn {
  font-size: 15px;
  font-weight: 700;
  color: var(--archive-ink);
}

.archive-return__os-en {
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 2px;
}

.archive-footer {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  width: 100%;
  padding: 28px 0 calc(28px + env(safe-area-inset-bottom, 0px));
  border-top: 1px solid var(--archive-line);
  text-align: center;
  color: var(--archive-ink-faint);
  font-size: 15px;
  background: linear-gradient(180deg, transparent, rgba(5, 7, 13, 0.72) 40%);
}

.archive-footer b {
  color: var(--archive-ink);
}

/* ============ 开源档案库大箭头 CTA ============ */

.archive-os-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-top: 34px;
  padding: 26px 34px;
  padding-right: clamp(100px, 9vw, 150px); /* 避让右侧固定章节导航 */
  border: 1px solid rgba(244, 247, 251, 0.55);
  background:
    repeating-linear-gradient(
      135deg,
      rgba(11, 15, 23, 0.05) 0 1px,
      transparent 1px 10px
    ),
    var(--archive-card);
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 50%, calc(100% - 26px) 100%, 0 100%);
  color: var(--archive-card-ink);
  text-decoration: none;
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.38);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.archive-os-cta:hover {
  border-color: var(--archive-red);
  transform: translateX(6px);
  box-shadow: 0 24px 64px rgba(255, 45, 77, 0.28);
}

.archive-os-cta__text {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.archive-os-cta__cn {
  font-size: clamp(20px, 2.4vw, 28px);
  font-weight: 700;
  color: var(--archive-card-ink);
}

.archive-os-cta__en {
  font-family: var(--archive-font-en);
  font-size: 12px;
  letter-spacing: 3px;
  color: #5b6879;
}

.archive-os-cta__arrow {
  font-size: clamp(34px, 4vw, 52px);
  line-height: 1;
  color: var(--archive-red);
  transition: transform 0.3s ease, color 0.3s ease;
}

.archive-os-cta:hover .archive-os-cta__arrow {
  transform: translateX(10px);
  color: var(--archive-cyan);
}

/* ============ 兵种堆叠图集: 横屏贴边 / 斜线分割 / 悬停展开 ============
   双层 clip-path: 外层红蓝渐变留出 2px 斜线描边, 内层图片裁切 */

.unit-stack {
  --cut: 44px;
  width: 100vw;
  margin-left: calc(50% - 50vw);
  margin-top: 24px;
  display: flex;
  height: min(74vh, 640px);
  min-height: 440px;
  overflow: hidden;
}

.unit-slot {
  position: relative;
  flex: 1 1 0;
  min-width: 0;
  margin-left: calc(var(--cut) * -1);
  clip-path: polygon(
    var(--cut) 0,
    100% 0,
    calc(100% - var(--cut)) 100%,
    0 100%
  );
  background: linear-gradient(180deg, var(--archive-red), var(--archive-blue));
  cursor: pointer;
  transition: flex-grow 0.55s cubic-bezier(0.22, 1, 0.36, 1);
}

.unit-slot:first-child {
  margin-left: 0;
  clip-path: polygon(0 0, 100% 0, calc(100% - var(--cut)) 100%, 0 100%);
}

.unit-slot:last-child {
  clip-path: polygon(var(--cut) 0, 100% 0, 100% 100%, 0 100%);
}

.unit-slot:hover,
.unit-slot:focus-visible,
.unit-slot.is-active {
  flex-grow: 3.4;
}

.unit-slot:focus-visible {
  outline: none;
}

.unit-slot__media {
  position: absolute;
  inset: 0;
  clip-path: polygon(
    calc(var(--cut) + 2px) 0,
    100% 0,
    calc(100% - var(--cut)) 100%,
    2px 100%
  );
  background: var(--archive-bg);
}

.unit-slot:first-child .unit-slot__media {
  clip-path: polygon(0 0, 100% 0, calc(100% - var(--cut)) 100%, 0 100%);
}

.unit-slot:last-child .unit-slot__media {
  clip-path: polygon(calc(var(--cut) + 2px) 0, 100% 0, 100% 100%, 2px 100%);
}

.unit-slot__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(0.82) brightness(0.72);
  transform: scale(1.06);
  transition: filter 0.45s ease, transform 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}

.unit-slot:hover .unit-slot__media img,
.unit-slot:focus-visible .unit-slot__media img,
.unit-slot.is-active .unit-slot__media img {
  filter: saturate(1) brightness(0.95);
  transform: scale(1);
}

/* 科技感斜线纹理, 悬停时点亮 */
.unit-slot__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    135deg,
    rgba(127, 212, 255, 0.08) 0 1px,
    transparent 1px 10px
  );
  opacity: 0;
  transition: opacity 0.45s ease;
  pointer-events: none;
}

.unit-slot:hover .unit-slot__media::after,
.unit-slot:focus-visible .unit-slot__media::after,
.unit-slot.is-active .unit-slot__media::after {
  opacity: 1;
}

.unit-slot__scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    0deg,
    rgba(5, 7, 13, 0.88) 0%,
    rgba(5, 7, 13, 0.32) 34%,
    transparent 62%
  );
  pointer-events: none;
}

.unit-slot__info {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 22px 18px 20px calc(var(--cut) * 0.4 + 18px);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.unit-slot__index {
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 2px;
  color: var(--archive-cyan);
  white-space: nowrap;
}

.unit-slot__name {
  font-size: 26px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--archive-ink);
  white-space: nowrap;
  transition: font-size 0.45s ease;
}

.unit-slot:hover .unit-slot__name,
.unit-slot:focus-visible .unit-slot__name,
.unit-slot.is-active .unit-slot__name {
  font-size: clamp(30px, 3vw, 44px);
}

.unit-slot__en {
  margin-top: 4px;
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 2px;
  color: var(--archive-ink-dim);
  white-space: nowrap;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.4s ease 0.08s, transform 0.4s ease 0.08s;
}

.unit-slot__desc {
  margin-top: 10px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--archive-ink-dim);
  max-width: 420px;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.4s ease 0.14s, transform 0.4s ease 0.14s;
}

.unit-slot:hover .unit-slot__en,
.unit-slot:hover .unit-slot__desc,
.unit-slot:focus-visible .unit-slot__en,
.unit-slot:focus-visible .unit-slot__desc,
.unit-slot.is-active .unit-slot__en,
.unit-slot.is-active .unit-slot__desc {
  opacity: 1;
  transform: translateY(0);
}

/* 已开源兵种: 跳转对应开源镜像帖的标签, 一个兵种可有多个 */
.unit-slot__oss-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
  opacity: 0;
  transform: translateY(12px);
  transition:
    opacity 0.4s ease 0.2s,
    transform 0.4s ease 0.2s;
}

/* 舰载科技面板: 同款标签, 常显 */
.archive-tech__oss {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.unit-slot__oss,
.archive-tech__oss a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  font-family: var(--archive-font-en);
  font-size: 11px;
  letter-spacing: 1.5px;
  color: var(--archive-cyan);
  text-decoration: none;
  border: 1px solid rgba(127, 212, 255, 0.45);
  background: rgba(127, 212, 255, 0.08);
  clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  transition: background 0.25s ease;
}

.unit-slot__oss span,
.archive-tech__oss a span {
  transition: transform 0.25s ease;
}

.unit-slot__oss:hover,
.archive-tech__oss a:hover {
  background: rgba(127, 212, 255, 0.22);
}

.unit-slot__oss:hover span,
.archive-tech__oss a:hover span {
  transform: translateX(4px);
}

.unit-slot:hover .unit-slot__oss-list,
.unit-slot:focus-visible .unit-slot__oss-list,
.unit-slot.is-active .unit-slot__oss-list {
  opacity: 1;
  transform: translateY(0);
}

/* 未知兵种: 问号白墨在深色斜纹底上 */
.unit-slot--unknown .unit-slot__media {
  background:
    repeating-linear-gradient(
      135deg,
      rgba(255, 45, 77, 0.07) 0 1px,
      transparent 1px 12px
    ),
    var(--archive-bg);
}

/* 原图是黑墨 + 透明底, 反相成白墨 */
.unit-slot--unknown .unit-slot__media img {
  object-fit: contain;
  padding: 12%;
  filter: invert(1) brightness(0.55);
}

.unit-slot--unknown:hover .unit-slot__media img,
.unit-slot--unknown:focus-visible .unit-slot__media img,
.unit-slot--unknown.is-active .unit-slot__media img {
  filter: invert(1) brightness(1) drop-shadow(0 0 26px rgba(255, 45, 77, 0.4));
}

.unit-slot--unknown .unit-slot__index {
  color: var(--archive-red);
}

/* 末格文字避开右侧固定章节导航 */
.unit-slot:last-child .unit-slot__info {
  padding-right: 96px;
}

/* 移动端: 改为纵向手风琴, 斜切落在每条的上沿 */
@media (max-width: 900px) {
  .unit-stack {
    --cut: 26px;
    flex-direction: column;
    height: 760px;
    min-height: 0;
  }

  .unit-slot {
    margin-left: 0;
    margin-top: calc(var(--cut) * -1);
    clip-path: polygon(0 var(--cut), 100% 0, 100% 100%, 0 100%);
  }

  .unit-slot:first-child {
    margin-top: 0;
    clip-path: none;
  }

  .unit-slot:last-child {
    clip-path: polygon(0 var(--cut), 100% 0, 100% 100%, 0 100%);
  }

  .unit-slot:hover,
  .unit-slot:focus-visible,
  .unit-slot.is-active {
    flex-grow: 3.8;
  }

  .unit-slot__media {
    clip-path: polygon(0 calc(var(--cut) + 2px), 100% 2px, 100% 100%, 0 100%);
  }

  .unit-slot:first-child .unit-slot__media {
    clip-path: none;
  }

  .unit-slot:last-child .unit-slot__media {
    clip-path: polygon(0 calc(var(--cut) + 2px), 100% 2px, 100% 100%, 0 100%);
  }

  .unit-slot__info {
    padding: 14px 18px calc(var(--cut) + 12px);
    flex-direction: row;
    align-items: baseline;
    gap: 12px;
    flex-wrap: wrap;
  }

  .unit-slot__name {
    font-size: 22px;
  }

  .unit-slot:hover .unit-slot__name,
  .unit-slot:focus-visible .unit-slot__name,
  .unit-slot.is-active .unit-slot__name {
    font-size: 26px;
  }

  .unit-slot__desc {
    flex-basis: 100%;
    margin-top: 4px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .unit-slot,
  .unit-slot__media img,
  .unit-slot__en,
  .unit-slot__desc,
  .unit-slot__name {
    transition: none;
  }
}

/* ============ 导航与进度 ============ */

.archive-nav {
  position: fixed;
  right: 26px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 80;
  display: flex;
  flex-direction: column;
  gap: 18px;
  /* 仅在档案模式 (is-document-mode) 显示, 3D 阶段隐藏 */
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.4s ease, visibility 0.4s ease;
}

html.is-document-mode .unit-site.is-archive-active .archive-nav {
  opacity: 1;
  visibility: visible;
}

.archive-nav__item {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  background: none;
  border: none;
  color: var(--archive-ink-faint);
  cursor: pointer;
  font-family: var(--archive-font-en);
  font-size: 13px;
  letter-spacing: 2px;
  transition: color 0.25s ease;
}

.archive-nav__item:hover,
.archive-nav__item.is-active {
  color: var(--archive-red);
}

.archive-nav__num {
  opacity: 0.7;
}

.archive-nav__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: currentColor;
  transition: box-shadow 0.25s ease;
}

.archive-nav__item.is-active .archive-nav__dot {
  box-shadow: 0 0 0 6px rgba(255, 45, 77, 0.2);
}

.archive-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  z-index: 80;
  background: var(--archive-line);
  /* 同导航: 仅在档案模式显示 */
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.4s ease, visibility 0.4s ease;
}

html.is-document-mode .unit-site.is-archive-active .archive-progress {
  opacity: 1;
  visibility: visible;
}

.archive-progress__fill {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--archive-red), var(--archive-blue));
  transform-origin: left;
  transform: scaleX(0);
}

/* reveal */
.reveal {
  opacity: 0;
  transform: translateY(36px);
  transition: opacity 0.75s ease, transform 0.75s cubic-bezier(0.22, 1, 0.36, 1);
  transition-delay: var(--rd, 0ms);
}

.reveal.is-in {
  opacity: 1;
  transform: translateY(0);
}

.archive-note {
  margin-top: 36px;
  font-size: 15px;
  color: var(--archive-ink-faint);
  line-height: 1.85;
}

/* ============ 响应式 ============ */

@media (max-width: 1080px) {
  .archive-hero__media::before {
    background: linear-gradient(
      100deg,
      var(--archive-card) 0%,
      rgba(244, 247, 251, 0.94) 42%,
      rgba(244, 247, 251, 0.72) 68%,
      rgba(244, 247, 251, 0.35) 100%
    );
  }

  .archive-hero__media .archive-hero__logo {
    width: min(63%, 300px);
    inset: auto 12% 8% auto;
    margin: 0;
  }

  .archive-scrollcue {
    left: 50%;
    transform: translateX(-50%);
  }

  .archive-stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .archive-flag,
  .archive-circuit__row--right .archive-flag {
    width: 100%;
    min-height: 260px;
    clip-path: none;
    padding: 44px 8vw;
    text-align: left;
    align-items: flex-start;
  }

  .archive-circuit__row::before,
  .archive-circuit__row::after {
    display: none;
  }

  .archive-grid--2,
  .archive-duo {
    grid-template-columns: 1fr;
  }

  /* 竖屏: 舰载科技 / 开源墙 / 新生培训 均堆叠为单列 */
  .archive-tech,
  .archive-repos,
  .archive-training {
    grid-template-columns: 1fr;
  }

  .archive-tech__figure {
    padding: 22px 20px 24px;
  }

  /* 竖屏: 去掉竖向分隔线, 改为上下堆叠 + 横向细线 */
  .archive-duo__col {
    padding: 8px 0;
  }

  .archive-duo__col + .archive-duo__col {
    border-left: none;
    border-top: 1px solid var(--archive-line);
    margin-top: 32px;
    padding: 40px 0 8px;
  }

  /* 竖屏: 航线改为纵向时间线, 旗帜内联、节点挂到左侧竖线上 */
  .archive-steps {
    grid-template-columns: 1fr;
    gap: 44px;
    padding-left: 36px;
  }

  .archive-steps::before {
    content: "";
    display: block;
    position: absolute;
    top: 20px;
    bottom: 20px;
    left: 7px;
    right: auto;
    width: 2px;
    height: auto;
    background: linear-gradient(
      180deg,
      var(--archive-red),
      var(--archive-blue)
    );
    opacity: 0.4;
  }

  .archive-steps li::before {
    display: none;
  }

  .archive-steps__mast {
    height: auto;
    margin-bottom: 14px;
  }

  .archive-steps__flag {
    position: static;
  }

  .archive-steps__pole {
    display: none;
  }

  .archive-steps__node {
    left: -35px;
    top: 11px;
    bottom: auto;
  }

  .archive-media-row {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .archive-media-row__visual {
    min-height: 300px;
  }

  .archive-media-row__visual::after {
    background: linear-gradient(
      0deg,
      transparent 0%,
      transparent 55%,
      rgba(244, 247, 251, 0.75) 82%,
      var(--archive-card) 96%
    );
  }

  .archive-dept {
    grid-template-columns: 1fr;
    gap: 18px;
    clip-path: none;
  }

  .archive-media__player {
    max-height: none;
  }

  .archive-nav {
    display: none;
  }
}

@media (max-width: 600px) {
  .archive-hero__copy {
    padding-inline: 20px;
  }

  .archive-hero__title {
    width: max-content;
    max-width: 100%;
    font-size: clamp(32px, 10.5vw, 44px);
    white-space: nowrap;
    overflow-wrap: normal;
    word-break: keep-all;
  }

  .archive-hero__media .archive-hero__logo {
    display: none;
  }

  .archive-stats {
    grid-template-columns: 1fr;
  }

  .archive-stat {
    min-height: 132px;
    padding: 23px 22px 20px;
  }
}

/* ============ What is RoboMaster: 媒体框视频变体 ============
   嵌入方式与参考站一致 (懒加载 bilibili iframe)。
   置于文件末尾: 需要压过上方媒体查询里的 min-height:300px 等规则。
   行框恒为 100vw 全幅, 因此 iframe 高度直接用 56.25vw (16:9),
   避免 aspect-ratio 在网格内在尺寸计算中反向推导宽度导致溢出。 */
.archive-media-row--intro .archive-media-row__visual--video {
  min-width: 0;
  min-height: 0;
  position: relative;
}

.archive-media-row--intro .archive-media-row__visual--video iframe {
  display: block;
  width: 100%;
  height: 56.25vw;
  border: 0;
  background: #000;
}

@media (max-width: 1080px) {
  /* 桌面右内边距 172px 会把网格轨道 min-content 撑出视口, 窄屏收敛 */
  .archive-media-row--intro .archive-media-row__body {
    padding: 40px 28px 44px;
  }
}

@media (min-width: 1081px) {
  .archive-media-row--intro .archive-media-row__visual--video {
    min-height: 480px;
  }

  .archive-media-row--intro .archive-media-row__visual--video iframe {
    position: absolute;
    inset: 0;
    height: 100%;
  }
}

/* 启动窗口整体不渲染档案页(2026-09-27 性能优化): 非文档模式 display:none——
   此前档案内容在布局树内(3D 覆盖层之下), 其中图片/CSS 背景在 ARENA READY 前就抢带宽
   (~2.7MB: 部门蓝图 1.6MB + 照片墙 + hero/banner); 文档模式激活时恢复,
   关键图已由 main.js 的就绪后低优先级预热写入 HTTP 缓存, 进场无突现 */
html:not(.is-document-mode) .unit-site {
  display: none;
}