/* ============================================================
   BryanSpine 私人网站 · 全局样式
   想换主色调？只需修改下面 :root 里的 --brand 系列变量
   ============================================================ */

:root {
  /* ---- 主色调（取自 logo 实测主色 #24B5BD，为保证文字对比度向下压深）---- */
  --brand: #148a90;
  --brand-600: #0d6b70;
  --brand-700: #095357;
  --brand-400: #24b5bd;
  --brand-200: #a4dde1;
  --brand-50: #e6f6f7;

  /* ---- 辅助色 ---- */
  --accent: #b4531f;
  --xhs: #e5342a;
  --weibo: #e6162d;

  /* ---- 中性色 ---- */
  --ink: #0f2225;
  --ink-2: #31484a;
  --muted: #5a7072;
  --line: rgba(20, 138, 144, 0.15);
  --line-2: rgba(15, 34, 37, 0.1);
  --bg: #fbfdfd;
  --card: #ffffff;

  /* ---- 尺度 ---- */
  --radius: 16px;
  --radius-sm: 10px;
  --maxw: 980px;
  --shadow: 0 1px 2px rgba(15, 34, 37, 0.04), 0 10px 28px rgba(15, 34, 37, 0.06);
  --shadow-hover: 0 2px 6px rgba(15, 34, 37, 0.06), 0 18px 44px rgba(20, 138, 144, 0.16);

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; }

/* ---------- 背景光晕 ---------- */
.aura {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(52vw 46vh at 12% -8%, var(--brand-50) 0%, transparent 62%),
    radial-gradient(44vw 40vh at 92% 4%, rgba(14, 124, 123, 0.07) 0%, transparent 60%),
    radial-gradient(60vw 50vh at 50% 108%, rgba(180, 83, 31, 0.05) 0%, transparent 65%);
}

/* ---------- 顶栏 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 24px;
  background: rgba(251, 253, 253, 0.82);
  backdrop-filter: saturate(1.6) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease;
}
.site-header.scrolled { border-bottom-color: var(--line); }

.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  min-width: 0;
}
.brand-lockup img { height: 32px; width: auto; }
.brand-lockup .wordmark {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--brand-600);
  white-space: nowrap;
}
.brand-lockup:hover .wordmark { color: var(--brand); }

/* ---------- 语言切换 ---------- */
.lang-switch {
  display: inline-flex;
  padding: 3px;
  gap: 2px;
  background: var(--brand-50);
  border: 1px solid var(--line);
  border-radius: 999px;
}
.lang-switch button {
  appearance: none;
  border: 0;
  background: transparent;
  color: var(--muted);
  font-family: inherit;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  padding: 5px 14px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}
.lang-switch button:hover { color: var(--brand-600); }
.lang-switch button[aria-pressed="true"] {
  background: var(--brand);
  color: #fff;
}

/* ---------- 主体 ---------- */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 40px 24px 88px;
}

.page-head {
  margin-bottom: 36px;
}
.page-head .eyebrow {
  font-size: 13px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand);
  margin: 0 0 10px;
}
.page-head h1 {
  font-size: 30px;
  line-height: 1.3;
  margin: 0 0 12px;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.page-head .lede {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  max-width: 62ch;
}

/* ---------- 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 26px;
}
.crumbs a { text-decoration: none; color: var(--brand-600); }
.crumbs a:hover { text-decoration: underline; }
.crumbs .sep { opacity: 0.45; }

/* ============================================================
   首页
   ============================================================ */
.hero {
  min-height: calc(100dvh - 68px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 0 72px;
  gap: 0;
}

.hero-logo-link {
  display: block;
  width: clamp(190px, 42vw, 280px);
}
.hero-logo {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 22px;
  box-shadow: 0 18px 50px rgba(20, 138, 144, 0.22);
  transition: transform 0.45s cubic-bezier(0.2, 0.7, 0.3, 1),
    box-shadow 0.45s ease;
}
.hero-logo-link:hover .hero-logo {
  transform: translateY(-6px) scale(1.015);
  box-shadow: 0 26px 66px rgba(20, 138, 144, 0.3);
}

.hero-title {
  display: block;
  margin: 34px 0 0;
  padding: 0;
  border: 0;
  background: transparent;
  font-family: inherit;
  font-size: clamp(28px, 6vw, 46px);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-decoration: none;
  cursor: pointer;
  transition: color 0.25s ease;
}
.hero-title:hover { color: var(--brand); }

.hero-sub {
  margin: 14px auto 0;
  max-width: 34ch;
  color: var(--muted);
  font-size: 16px;
}

.hero-cta {
  margin-top: 34px;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--brand-600);
  font-size: 13px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  background: none;
  border: 0;
  font-family: inherit;
  cursor: pointer;
  padding: 10px 18px;
  border-radius: 999px;
}
.hero-cta .arrow {
  width: 15px;
  height: 15px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg);
  animation: nudge 2.1s ease-in-out infinite;
}
@keyframes nudge {
  0%, 100% { transform: rotate(45deg) translate(0, 0); }
  50% { transform: rotate(45deg) translate(4px, 4px); }
}
@media (prefers-reduced-motion: reduce) {
  .hero-cta .arrow { animation: none; }
  html { scroll-behavior: auto; }
}

/* ============================================================
   第二层 · 入口卡片
   ============================================================ */
.entry-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(268px, 1fr));
  gap: 18px;
}

.entry-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 26px 24px 24px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: transform 0.3s cubic-bezier(0.2, 0.7, 0.3, 1), box-shadow 0.3s ease,
    border-color 0.3s ease;
  min-height: 178px;
}
.entry-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--brand-200);
}
.entry-card:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
}

.entry-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: var(--brand-50);
  color: var(--brand-600);
  flex: none;
}
.entry-icon svg { width: 22px; height: 22px; }

.entry-index {
  position: absolute;
  top: 22px;
  right: 24px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--brand-400);
  letter-spacing: 0.08em;
}

.entry-card h3 {
  margin: 0;
  font-size: 18px;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.entry-card p {
  margin: 0;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
  flex: 1;
}
.entry-card .go {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--brand-600);
  font-weight: 500;
}
.entry-card:hover .go .arrow { transform: translateX(4px); }
.entry-card .go .arrow {
  width: 12px;
  height: 12px;
  border-right: 1.5px solid currentColor;
  border-top: 1.5px solid currentColor;
  transform: rotate(45deg);
  transition: transform 0.25s ease;
}

/* 置顶推荐卡：成果概览 */
.entry-card-featured {
  border-color: var(--brand-200);
  background: linear-gradient(140deg, var(--brand-50) 0%, #fff 62%);
}
.entry-card-featured .entry-index {
  color: var(--brand-600);
  font-size: 15px;
  top: 20px;
}
.entry-card-featured:hover { border-color: var(--brand-400); }

/* ============================================================
   通用内容块
   ============================================================ */
.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 28px;
  box-shadow: var(--shadow);
}
.panel + .panel { margin-top: 20px; }

.stack > * + * { margin-top: 20px; }

/* 照片位 */
.photo-slot {
  width: 100%;
  aspect-ratio: 4 / 5;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--brand-50);
  border: 1px solid var(--line);
}
.photo-slot img { width: 100%; height: 100%; object-fit: cover; }
.photo-slot.photo-wide { aspect-ratio: 16 / 9; }

/* 空状态 */
.empty {
  text-align: center;
  padding: 62px 24px;
  border: 1px dashed var(--brand-200);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--brand-50) 0%, rgba(255, 255, 255, 0) 100%);
}
.empty .mark {
  width: 54px;
  height: 54px;
  margin: 0 auto 18px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: #fff;
  border: 1px solid var(--line);
  color: var(--brand-400);
}
.empty .mark svg { width: 24px; height: 24px; }
.empty h3 { margin: 0 0 8px; font-size: 17px; font-weight: 600; }
.empty p {
  margin: 0 auto;
  max-width: 40ch;
  color: var(--muted);
  font-size: 14px;
}

/* 社交卡 */
.social-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}
.social-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 28px 24px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  text-align: center;
}
.social-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
  color: #fff;
}
.social-badge.xhs { background: var(--xhs); }
.social-badge.weibo { background: var(--weibo); }

.qr-frame {
  display: block;
  padding: 14px;
  background: #fff;
  border: 1px solid var(--line-2);
  border-radius: var(--radius-sm);
  line-height: 0;
  cursor: zoom-in;
  transition: border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
}
.qr-frame:hover {
  border-color: var(--brand-200);
  box-shadow: 0 6px 22px rgba(20, 138, 144, 0.16);
  transform: translateY(-2px);
}
.qr-frame:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }
.qr-frame img {
  width: 100%;
  max-width: 260px;
  height: auto;
  aspect-ratio: 1;
  object-fit: contain;
  margin: 0 auto;
}

/* 二维码灯箱：点击后全屏放大，方便手机扫 */
.qr-lightbox {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 28px;
  background: rgba(9, 26, 28, 0.92);
  backdrop-filter: blur(6px);
}
.qr-lightbox.is-open { display: flex; }
.qr-lightbox img {
  width: min(78vw, 78vh, 460px);
  height: auto;
  aspect-ratio: 1;
  object-fit: contain;
  border-radius: 18px;
  background: #fff;
  padding: 16px;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.45);
}
.qr-lightbox .lb-title {
  color: #fff;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.02em;
}
.qr-lightbox .lb-close {
  position: absolute;
  top: 18px;
  right: 20px;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 0;
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
}
.qr-lightbox .lb-close:hover { background: rgba(255, 255, 255, 0.24); }

.social-actions { display: flex; gap: 10px; flex-wrap: wrap; justify-content: center; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 10px 20px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  font-family: inherit;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-600); }
.btn-ghost { background: transparent; color: var(--brand-600); border-color: var(--brand-200); }
.btn-ghost:hover { background: var(--brand-50); }
.btn[aria-disabled="true"], .btn.is-empty {
  background: var(--brand-50);
  color: var(--muted);
  border-color: var(--line);
  cursor: not-allowed;
  pointer-events: none;
}
.btn svg { width: 15px; height: 15px; }

/* 版本列表 */
.version-list { display: flex; flex-direction: column; gap: 12px; }
.version-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card);
  text-decoration: none;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}
.version-item:hover {
  border-color: var(--brand-200);
  transform: translateX(3px);
  box-shadow: var(--shadow);
}
.version-tag {
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-weight: 500;
  color: var(--brand-600);
  background: var(--brand-50);
  border-radius: 6px;
  padding: 4px 10px;
  flex: none;
  min-width: 84px;
  text-align: center;
}
.version-meta { flex: 1; min-width: 0; }
.version-meta strong { display: block; font-size: 15px; font-weight: 500; }
.version-meta span { font-size: 13px; color: var(--muted); }

/* 社团卡 */
.club-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: transform 0.28s ease, box-shadow 0.28s ease, border-color 0.28s ease;
}
.club-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
  border-color: var(--brand-200);
}
.club-thumb {
  width: 84px;
  height: 84px;
  flex: none;
  border-radius: 12px;
  overflow: hidden;
  background: var(--brand-50);
}
.club-thumb img { width: 100%; height: 100%; object-fit: cover; }
.club-body { flex: 1; min-width: 0; }
.club-body h3 { margin: 0 0 4px; font-size: 17px; font-weight: 600; }
.club-body p { margin: 0; font-size: 14px; color: var(--muted); }
.club-card .go {
  flex: none;
  color: var(--brand-400);
}
.club-card .go svg { width: 18px; height: 18px; }

.locked {
  opacity: 0.62;
}
.locked .club-thumb { filter: grayscale(1); }

/* 正文长文（社团介绍预留） */
.prose { font-size: 16px; color: var(--ink-2); }
.prose p { margin: 0 0 16px; }
.prose p:last-child { margin-bottom: 0; }

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 26px 24px 34px;
  text-align: center;
  color: var(--muted);
  font-size: 13px;
}
.site-footer .credits { margin: 0 0 6px; }
.site-footer .icp { margin: 0; font-size: 12px; opacity: 0.85; }
/* 备案号链接比邮箱链接更淡一级，避免与联系方式抢注意力 */
.site-footer .icp a { color: var(--muted); opacity: 0.9; }
.site-footer .icp a:hover { color: var(--brand-600); opacity: 1; }
.site-footer a { color: var(--brand-600); text-decoration: none; }
.site-footer a:hover { text-decoration: underline; }

/* 页脚无任何可见内容时（如未填联系方式与备案号），整体隐藏不占空间 */
.site-footer:has(> .foot-contact[hidden] > .icp[hidden]:only-child) { display: none; }

/* 首页页脚只在有内容时才留出底部间距 */
.hero-footer { border-top: 0; padding: 0; }
.hero-footer:has(> .foot-contact[hidden] > .icp[hidden]:only-child) { display: none; }
.hero-footer .foot-contact,
.hero-footer .icp { padding: 0 24px 30px; }

/* ============================================================
   页面级小布局
   ============================================================ */

/* 关于页：照片居中，窄一些更好看；上方为主线动机区块 */
.about-layout {
  display: flex;
  justify-content: center;
  margin-top: 28px;
}
.about-layout .photo-slot {
  width: min(100%, 420px);
  box-shadow: var(--shadow-hover);
}

/* 社团详情：封面图 */
.club-hero { margin-bottom: 20px; }
.club-hero .photo-slot {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  background: var(--brand-50);
}
.club-hero img { width: 100%; height: 100%; object-fit: cover; }

/* ============================================================
   工具演进链
   ============================================================ */
.chain {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0;
  position: relative;
  margin-bottom: 8px;
}
.chain-step {
  position: relative;
  padding: 20px 22px 20px 26px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
/* 有链接的阶段：整块可点，给出与 stat-card 一致的悬停反馈 */
.chain-step.is-link {
  display: block;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
  transition: transform 0.28s cubic-bezier(0.2, 0.7, 0.3, 1), box-shadow 0.28s ease,
    border-color 0.28s ease;
}
.chain-step.is-link:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--brand-200);
}
.chain-step.is-link:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }
.chain-go {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-top: 12px;
  font-size: 13px;
  font-weight: 500;
  color: var(--brand-600);
}
.chain-step.is-link:hover .chain-go { text-decoration: underline; }
.chain-step + .chain-step { margin-left: -1px; }
.chain-step.is-live {
  border-color: var(--brand-200);
  background: linear-gradient(160deg, var(--brand-50) 0%, #fff 70%);
}
.chain-step.is-building {
  border-style: dashed;
  border-color: var(--brand-200);
}
.chain-step.is-plan {
  background: #fcfdfd;
  border-style: dashed;
}
.chain-stage {
  display: inline-block;
  font-size: 11.5px;
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
  color: var(--brand-600);
  background: var(--brand-50);
  border-radius: 5px;
  padding: 3px 9px;
  margin-bottom: 10px;
}
.chain-step.is-plan .chain-stage,
.chain-step.is-building .chain-stage {
  background: transparent;
  border: 1px solid var(--brand-200);
  color: var(--muted);
}
.chain-name {
  margin: 0 0 6px;
  font-size: 15.5px;
  font-weight: 600;
  line-height: 1.4;
}
.chain-desc {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

@media (max-width: 640px) {
  .chain-step + .chain-step { margin-left: 0; margin-top: -1px; }
}

/* ============================================================
   成果概览 · 数据卡片
   ============================================================ */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}
.stat-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: flex-start;
  gap: 8px;
  padding: 26px 22px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  text-decoration: none;
  /* 同一行卡片等高，标签长短不一时底部仍对齐 */
  min-height: 132px;
  transition: transform 0.28s cubic-bezier(0.2, 0.7, 0.3, 1), box-shadow 0.28s ease,
    border-color 0.28s ease;
}
a.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--brand-200);
}
a.stat-card:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }
.stat-card.is-static { cursor: default; }

.stat-value {
  font-size: 34px;
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: var(--brand-600);
  font-variant-numeric: tabular-nums;
  margin-bottom: 2px;
}
.stat-label {
  font-size: 14px;
  line-height: 1.6;
  color: var(--muted);
  text-wrap: pretty;
}

.note-panel { margin-top: 20px; }
.note-text {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.7;
}



/* ============================================================
   工具页 · 开放源码区块
   ============================================================ */
.oss-panel {
  margin-top: 44px;
  padding: 30px 28px 26px;
  background: linear-gradient(160deg, var(--brand-50) 0%, #fff 62%);
  border: 1px solid var(--brand-200);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.oss-head { display: flex; align-items: center; gap: 16px; }
.oss-logo {
  width: 52px; height: 52px; border-radius: 12px; flex: 0 0 auto;
  border: 1px solid var(--line-2); background: #fff;
}
.oss-head-txt { flex: 1; min-width: 0; }
.oss-eyebrow {
  font-size: 12px; font-weight: 600; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--brand-600);
}
.oss-title { font-size: 20px; font-weight: 600; margin: 2px 0 0; letter-spacing: -0.01em; }
.oss-badge {
  align-self: flex-start; flex: 0 0 auto;
  padding: 5px 12px; border-radius: 999px;
  font-size: 12px; font-weight: 600;
  background: #fff; color: var(--brand-600); border: 1px solid var(--brand-200);
}
.oss-lede {
  margin: 20px 0 0; font-size: 15px; line-height: 1.75; color: var(--ink-2);
  max-width: 62ch;
}
.oss-grid {
  list-style: none; margin: 22px 0 0; padding: 0;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(168px, 1fr)); gap: 10px;
}
.oss-grid li {
  display: flex; align-items: flex-start; gap: 8px;
  padding: 11px 13px; font-size: 13.5px; line-height: 1.5;
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius-sm); color: var(--ink-2);
}
.oss-grid li::before {
  content: ""; flex: 0 0 auto; width: 15px; height: 15px; margin-top: 2px;
  border-radius: 50%; background: var(--brand-50);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%230d6b70' stroke-width='3.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E");
  background-size: 11px 11px; background-repeat: no-repeat; background-position: center;
}
.oss-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.oss-btn {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 13px 24px; border-radius: 999px;
  font-size: 14.5px; font-weight: 500; font-family: inherit;
  text-decoration: none; cursor: pointer; border: 1px solid transparent;
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}
.oss-btn-primary { background: var(--brand); color: #fff; }
.oss-btn-primary:hover { background: var(--brand-600); transform: translateY(-1px); }
.oss-btn-ghost { background: var(--card); color: var(--brand-600); border-color: var(--brand-200); }
.oss-btn-ghost:hover { background: var(--brand-50); border-color: var(--brand-400); }
.oss-btn:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }

.oss-terms {
  margin: 22px 0 0; padding: 16px 18px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  font-size: 13.5px; line-height: 1.8; color: var(--muted);
}
.oss-terms b { color: var(--ink-2); font-weight: 600; }
.oss-terms code {
  font-family: var(--font-mono); font-size: 12.5px;
  background: var(--brand-50); color: var(--brand-600);
  padding: 1px 5px; border-radius: 4px;
}

.oss-brand {
  margin-top: 16px; padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 13.5px; line-height: 1.8; color: var(--muted);
}
.oss-brand-head {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; color: var(--brand-600);
  letter-spacing: 0.02em; margin-bottom: 8px;
}
.oss-brand-head::before {
  content: ""; width: 4px; height: 15px; border-radius: 2px; background: var(--brand-400);
}
.oss-brand b { color: var(--ink-2); }
.oss-tm {
  display: inline-block; margin-top: 10px;
  padding: 5px 12px; border-radius: 999px;
  font-size: 12.5px; font-weight: 500;
  background: rgba(180, 83, 31, 0.08); color: var(--accent);
  border: 1px solid rgba(180, 83, 31, 0.2);
}
@media (max-width: 560px) {
  .oss-panel { padding: 24px 20px 22px; }
  /* 徽标独占一行，否则会挤压标题只剩几十像素导致逐字换行 */
  .oss-head { flex-wrap: wrap; gap: 12px; }
  .oss-head-txt { flex: 1 1 calc(100% - 68px); }
  .oss-badge { flex: 1 1 100%; align-self: flex-start; text-align: center; }
  .oss-title { font-size: 18px; }
  .oss-lede { font-size: 14.5px; }
  .oss-grid { grid-template-columns: 1fr 1fr; }
  .oss-btn { flex: 1 1 100%; justify-content: center; }
}
/* ============================================================
   时间线
   ============================================================ */
.timeline {
  position: relative;
  padding-left: 30px;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--brand-200) 0%, var(--line) 100%);
  border-radius: 2px;
}

.tl-item {
  position: relative;
  padding-bottom: 30px;
}
.tl-item:last-child { padding-bottom: 0; }

.tl-marker {
  position: absolute;
  left: -30px;
  top: 5px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #fff;
  border: 2.5px solid var(--brand);
  box-shadow: 0 0 0 4px var(--brand-50);
}

.tl-time {
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--brand-600);
  margin-bottom: 5px;
}
.tl-body h3 {
  margin: 0 0 5px;
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.tl-body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ============================================================
   页脚联系方式
   ============================================================ */
.foot-contact {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 4px;
}
.foot-item {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
}
.foot-label { color: var(--muted); opacity: 0.75; }
.foot-link { color: var(--brand-600); text-decoration: none; font-weight: 500; }
.foot-link:hover { text-decoration: underline; }
.foot-sep { opacity: 0.4; }

/* 荣誉分组：学术奖项 / 其他奖项 */
.honor-groups { display: flex; flex-direction: column; gap: 36px; }
.honor-group-title {
  margin: 0 0 14px;
  font-size: 16px;
  font-weight: 600;
  color: var(--brand-600);
  letter-spacing: 0.01em;
  display: flex;
  align-items: center;
  gap: 10px;
}
.honor-group-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

/* 社团列表 */
.club-list { display: flex; flex-direction: column; gap: 16px; }

/* 社交卡提示文字 */
.social-hint {
  margin: -4px 0 0;
  font-size: 13px;
  color: var(--muted);
}

/* 工具启动条 */
.tool-launch {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
  padding: 28px 26px;
  background: linear-gradient(135deg, var(--brand-50) 0%, rgba(255, 255, 255, 0.7) 100%);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.tool-launch-body h2 { margin: 0 0 6px; font-size: 19px; font-weight: 600; }
.tool-launch-body p { margin: 0; font-size: 14px; color: var(--muted); }
.btn-lg { padding: 13px 26px; font-size: 15px; }

/* 小节标题 */
.section-title {
  margin: 40px 0 16px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--brand-600);
}

/* 版本条目补充 */
.version-item.is-static { cursor: default; }
.version-item.is-static:hover {
  transform: none;
  box-shadow: none;
  border-color: var(--line);
}
.version-note {
  flex: none;
  font-size: 13px;
  color: var(--brand-600);
  font-weight: 500;
  white-space: nowrap;
}
.version-item.is-static .version-note { color: var(--muted); font-weight: 400; }

@media (max-width: 640px) {
  .tool-launch { flex-direction: column; align-items: stretch; text-align: center; }
  .tool-launch .btn { justify-content: center; }
  .about-layout .photo-slot { width: 100%; }
}

/* ---------- 返回按钮 ---------- */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 22px;
  font-size: 14px;
  color: var(--brand-600);
  text-decoration: none;
}
.back-link .arrow {
  width: 11px;
  height: 11px;
  border-left: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg);
}
.back-link:hover { text-decoration: underline; }

/* ---------- 响应式 ---------- */
@media (max-width: 640px) {
  body { font-size: 15px; }
  main { padding: 28px 18px 72px; }
  .site-header { padding: 12px 18px; }
  .page-head h1 { font-size: 25px; }
  .panel { padding: 24px 20px; }
  .hero { min-height: calc(100dvh - 62px); }
  .club-card { flex-direction: column; align-items: flex-start; gap: 14px; }
}

@media print {
  .site-header, .site-footer, .aura { display: none; }
}