/* =========================================================
   777游戏礼包 · 共享样式表 /assets/site.css
   夜间游戏大厅 × 展览画册
   ========================================================= */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd,
ol, ul { margin: 0; }

ol, ul { padding: 0; list-style: none; }

img, svg, video, picture { display: block; max-width: 100%; }

img { height: auto; }

button, input, select, textarea {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
}

a { color: inherit; text-decoration: none; }

/* ---------- 2. Tokens ---------- */
:root {
  /* 色彩 */
  --c-void: #0B0714;
  --c-stage: #151126;
  --c-violet: #8B5CF6;
  --c-cyan: #22D3EE;
  --c-gold: #FFD166;
  --c-orange: #FF7A3D;
  --c-stone: #2A2538;
  --c-paper: #F4F1EA;
  --c-mint: #4ADE80;

  --c-paper-2: rgba(244, 241, 234, 0.74);
  --c-paper-3: rgba(244, 241, 234, 0.52);
  --c-line-v: rgba(139, 92, 246, 0.30);
  --c-line-c: rgba(34, 211, 238, 0.32);
  --c-line-0: rgba(244, 241, 234, 0.10);

  --glow-v: 0 18px 44px -24px rgba(139, 92, 246, 0.95);
  --glow-c: 0 18px 44px -24px rgba(34, 211, 238, 0.85);

  /* 字体 */
  --font-head: "Noto Sans SC", "HarmonyOS Sans SC", "Source Han Sans SC",
    "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-body: "Noto Sans SC", "HarmonyOS Sans SC", "Source Han Sans SC",
    "PingFang SC", "Helvetica Neue", Arial, system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace,
    SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  /* 字号 */
  --fs-hero: clamp(2.25rem, 6vw, 5.5rem);
  --fs-h2: clamp(1.6rem, 3vw, 2.6rem);
  --fs-h3: clamp(1.125rem, 1.6vw, 1.4rem);

  /* 间距 */
  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 48px;
  --sp-8: 64px;
  --sp-9: 96px;

  /* 圆角 */
  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 22px;
  --r-pill: 999px;

  /* 动效 */
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur: 0.18s;

  /* 结构 */
  --rail-w: 248px;
  --bar-h: 68px;
  --shell: min(1200px, 100% - 2 * clamp(20px, 5vw, 64px));
}

/* ---------- 3. 基础排版 ---------- */
html { overflow-x: clip; }

body {
  min-height: 100vh;
  overflow-x: clip;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  color: var(--c-paper);
  background-color: var(--c-void);
  background-image:
    radial-gradient(58% 46% at 82% -6%, rgba(139, 92, 246, 0.24), transparent 64%),
    radial-gradient(46% 38% at 2% 4%, rgba(34, 211, 238, 0.13), transparent 66%),
    linear-gradient(rgba(139, 92, 246, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(139, 92, 246, 0.045) 1px, transparent 1px);
  background-size: 100% 1100px, 100% 980px, 72px 72px, 72px 72px;
  background-repeat: no-repeat, no-repeat, repeat, repeat;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--c-paper);
}

h1 { font-size: var(--fs-hero); line-height: 1.04; }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }

p { max-width: 68ch; }
p + p { margin-top: 0.9em; }

strong, b { font-weight: 700; color: var(--c-paper); }

code, kbd, samp, .mono {
  font-family: var(--font-mono);
  font-size: 0.92em;
  letter-spacing: 0.02em;
}

::selection {
  background: rgba(34, 211, 238, 0.32);
  color: #ffffff;
}

:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- 4. 通用容器与工具 ---------- */
.wrap {
  width: var(--shell);
  margin-inline: auto;
}

.wrap--narrow { max-width: 860px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--c-cyan);
}

.divider {
  height: 1px;
  border: 0;
  margin: clamp(28px, 4vw, 48px) 0;
  background: linear-gradient(90deg, transparent, var(--c-line-v), var(--c-line-c), transparent);
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- 5. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 18px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--c-paper-3);
}

.breadcrumb > li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--c-line-v);
}

.breadcrumb a {
  color: var(--c-paper-2);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.breadcrumb a:hover {
  color: var(--c-cyan);
  border-bottom-color: var(--c-line-c);
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 26px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition: background var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.btn:active { transform: translateY(1px); }

.btn--primary {
  color: #ffffff;
  background: linear-gradient(120deg, var(--c-violet), #6D3BE0 74%);
  box-shadow: var(--glow-v);
}

.btn--primary:hover {
  background: linear-gradient(120deg, #9D74F8, #7A48EC 74%);
  box-shadow: 0 22px 50px -22px rgba(139, 92, 246, 1);
}

.btn--cyan {
  color: #06121A;
  background: linear-gradient(120deg, var(--c-cyan), #0FB6D4 80%);
  box-shadow: var(--glow-c);
}

.btn--cyan:hover { background: linear-gradient(120deg, #4BE4F8, #16C4E2 80%); }

.btn--gold {
  color: #1A1206;
  background: linear-gradient(120deg, var(--c-gold), #F0B93C 80%);
}

.btn--gold:hover { background: linear-gradient(120deg, #FFDF8E, #FFC94F 80%); }

.btn--ghost {
  color: var(--c-paper);
  background: rgba(244, 241, 234, 0.04);
  border-color: var(--c-line-v);
}

.btn--ghost:hover {
  background: rgba(139, 92, 246, 0.16);
  border-color: var(--c-violet);
}

/* ---------- 7. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: var(--r-pill);
  border: 1px solid var(--c-line-c);
  background: rgba(34, 211, 238, 0.08);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  line-height: 1.6;
  color: var(--c-cyan);
  white-space: nowrap;
}

.tag--gold {
  color: var(--c-gold);
  border-color: rgba(255, 209, 102, 0.36);
  background: rgba(255, 209, 102, 0.08);
}

.tag--mint {
  color: var(--c-mint);
  border-color: rgba(74, 222, 128, 0.34);
  background: rgba(74, 222, 128, 0.08);
}

.tag--violet {
  color: #C8B0FF;
  border-color: rgba(139, 92, 246, 0.42);
  background: rgba(139, 92, 246, 0.14);
}

/* ---------- 8. 内容层 ---------- */
.card {
  position: relative;
  padding: clamp(18px, 2.4vw, 28px);
  border-radius: var(--r-lg);
  border: 1px solid var(--c-line-v);
  background: linear-gradient(180deg, rgba(30, 23, 54, 0.92), rgba(14, 10, 26, 0.96));
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.card:hover { border-color: rgba(139, 92, 246, 0.62); }

.card--glass {
  border-color: var(--c-line-0);
  background: rgba(21, 17, 38, 0.55);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  backdrop-filter: blur(12px) saturate(140%);
}

.plate {
  border-radius: var(--r-md);
  border: 1px solid var(--c-line-v);
  background: var(--c-stage);
  padding: clamp(14px, 2vw, 22px);
}

/* ---------- 9. 编号章节头 ---------- */
.section-head {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(22px, 3.2vw, 40px);
}

.section-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(30px, 4.6vw, 62px);
  line-height: 0.9;
  letter-spacing: -0.02em;
  color: rgba(139, 92, 246, 0.58);
}

.section-title {
  font-family: var(--font-head);
  font-size: clamp(1.5rem, 3vw, 2.5rem);
  font-weight: 800;
  line-height: 1.15;
}

.section-desc {
  max-width: 62ch;
  color: var(--c-paper-2);
  font-size: 16px;
}

/* ---------- 10. 网格 ---------- */
.grid {
  display: grid;
  gap: clamp(16px, 2vw, 26px);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* ---------- 11. 图片容器（页面阶段投放占位） ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  isolation: isolate;
  border-radius: var(--r-lg);
  border: 1px solid var(--c-line-v);
  background:
    linear-gradient(150deg, #1C1533, #0C0818 72%),
    var(--c-stage);
}

.media > img,
.media > picture > img,
.media > svg,
.media > video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: inherit;
  pointer-events: none;
  box-shadow: inset 0 0 0 1px rgba(244, 241, 234, 0.07);
}

.media--glow::after {
  box-shadow:
    inset 0 0 0 1px rgba(244, 241, 234, 0.07),
    inset 0 -70px 90px -60px rgba(34, 211, 238, 0.75),
    inset 0 70px 90px -60px rgba(139, 92, 246, 0.75);
}

.media--wide { aspect-ratio: 21 / 9; }
.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--square { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }

.media-caption {
  padding-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--c-paper-3);
}

/* ---------- 12. 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 400;
  padding: 10px 20px;
  border-radius: var(--r-pill);
  background: var(--c-cyan);
  color: #06121A;
  font-family: var(--font-head);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(-180%);
  transition: transform var(--dur) var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible { transform: translateY(0); }

/* ---------- 13. 阅读进度 ---------- */
.scroll-progress {
  position: fixed;
  inset: 0 0 auto 0;
  height: 3px;
  z-index: 300;
  pointer-events: none;
  background: rgba(244, 241, 234, 0.05);
}

.scroll-progress-bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--c-cyan), var(--c-violet) 54%, var(--c-orange));
  box-shadow: 0 0 14px rgba(34, 211, 238, 0.85);
}

/* ---------- 14. HEADER ---------- */
.site-header {
  position: relative;
  z-index: 80;
}

/* 命令栏 */
.command-bar {
  position: sticky;
  top: 0;
  z-index: 95;
  display: flex;
  align-items: center;
  gap: clamp(10px, 2vw, 22px);
  min-height: var(--bar-h);
  padding: 10px clamp(16px, 3.4vw, 36px);
  background: linear-gradient(100deg, rgba(21, 17, 38, 0.94), rgba(11, 7, 20, 0.88) 58%, rgba(21, 17, 38, 0.94));
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  border-bottom: 1px solid var(--c-line-v);
}

.command-bar::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-violet), var(--c-cyan), transparent);
  opacity: 0.55;
  pointer-events: none;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  margin-right: auto;
}

.brand-mark {
  display: grid;
  place-items: center;
  flex: none;
  min-width: 48px;
  height: 40px;
  padding: 0 9px;
  border-radius: 11px 4px 11px 4px;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: #0B0714;
  background: linear-gradient(135deg, var(--c-cyan), var(--c-violet) 74%);
  box-shadow: 0 0 0 1px rgba(34, 211, 238, 0.4), 0 10px 26px -14px rgba(139, 92, 246, 0.95);
}

.brand-text {
  display: grid;
  gap: 2px;
  min-width: 0;
}

.brand-name {
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.brand-tagline {
  font-size: 12px;
  line-height: 1.32;
  color: var(--c-paper-3);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 版本徽标 */
.version-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: none;
  padding: 6px 13px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(255, 209, 102, 0.34);
  background: rgba(255, 209, 102, 0.07);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--c-gold);
  white-space: nowrap;
}

.version-badge::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-mint);
  box-shadow: 0 0 9px var(--c-mint);
}

/* 导航按钮 */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: none;
  padding: 10px 15px;
  border-radius: var(--r-pill);
  border: 1px solid var(--c-line-v);
  background: rgba(139, 92, 246, 0.14);
  color: var(--c-paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  cursor: pointer;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.nav-toggle:hover {
  background: rgba(139, 92, 246, 0.28);
  border-color: var(--c-violet);
}

.nav-toggle-bars {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 18px;
  height: 14px;
}

.nav-toggle-bars i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.site-header[data-open="true"] .nav-toggle-bars i:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.site-header[data-open="true"] .nav-toggle-bars i:nth-child(2) { opacity: 0; }

.site-header[data-open="true"] .nav-toggle-bars i:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* 遮罩（仅移动端抽屉打开时） */
.site-header::after {
  content: "";
  position: fixed;
  inset: var(--bar-h) 0 0 0;
  z-index: 88;
  background: rgba(6, 4, 12, 0.7);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.24s var(--ease), visibility 0s linear 0.24s;
}

.site-header[data-open="true"]::after {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transition: opacity 0.24s var(--ease), visibility 0s;
}

/* ---------- 15. 导航轨道 / 抽屉 ---------- */
.site-nav {
  position: fixed;
  top: var(--bar-h);
  right: 0;
  bottom: 0;
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 24px;
  width: min(340px, 88vw);
  padding: 22px 18px 30px;
  overflow-y: auto;
  background: linear-gradient(180deg, #191331, #0C0818 72%);
  border-left: 1px solid var(--c-line-v);
  box-shadow: -32px 0 64px -34px rgba(0, 0, 0, 0.95);
  transform: translateX(105%);
  visibility: hidden;
  transition: transform 0.28s var(--ease), visibility 0s linear 0.28s;
}

.site-header[data-open="true"] .site-nav {
  transform: none;
  visibility: visible;
  transition: transform 0.28s var(--ease), visibility 0s;
}

.nav-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 0 10px;
}

.nav-head-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--c-paper-3);
}

.nav-head-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--c-cyan);
}

.nav-list {
  display: grid;
  gap: 4px;
}

.nav-item { min-width: 0; }

.nav-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 12px;
  border-radius: 10px;
  border-left: 2px solid transparent;
  color: var(--c-paper-2);
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 600;
  transition: background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.nav-index {
  flex: none;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: rgba(139, 92, 246, 0.9);
  transition: color var(--dur) var(--ease);
}

.nav-text { min-width: 0; }

.nav-link:hover {
  background: rgba(139, 92, 246, 0.14);
  color: var(--c-paper);
}

.nav-link:hover .nav-index { color: var(--c-cyan); }

.nav-link[aria-current="page"] {
  color: var(--c-paper);
  border-left-color: var(--c-cyan);
  background: linear-gradient(90deg, rgba(34, 211, 238, 0.16), rgba(139, 92, 246, 0.08) 78%, transparent);
}

.nav-link[aria-current="page"] .nav-index { color: var(--c-cyan); }

.nav-fixed {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px dashed var(--c-line-0);
}

.nav-fixed-title {
  padding: 0 10px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--c-paper-3);
}

.fixed-list { display: grid; gap: 6px; }

.fixed-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: var(--r-sm);
  border: 1px dashed rgba(255, 209, 102, 0.26);
  font-size: 14px;
  color: var(--c-paper-2);
  transition: color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              background var(--dur) var(--ease);
}

.fixed-link:hover {
  color: var(--c-gold);
  border-color: rgba(255, 209, 102, 0.68);
  background: rgba(255, 209, 102, 0.08);
}

.fixed-dot {
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-gold);
  box-shadow: 0 0 8px rgba(255, 209, 102, 0.9);
}

/* ---------- 16. FOOTER ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 120px);
  padding-top: clamp(44px, 6vw, 76px);
  border-top: 1px solid var(--c-line-v);
  background:
    radial-gradient(120% 150% at 10% 0%, rgba(139, 92, 246, 0.17), transparent 60%),
    radial-gradient(90% 130% at 92% 6%, rgba(34, 211, 238, 0.12), transparent 62%),
    #0A0616;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-cyan), var(--c-violet), var(--c-orange), transparent);
  opacity: 0.6;
  pointer-events: none;
}

.footer-grid {
  width: var(--shell);
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(220px, 1.5fr) 1fr 1fr minmax(240px, 1.35fr);
  gap: clamp(24px, 4vw, 52px);
  padding-bottom: clamp(34px, 5vw, 58px);
}

.footer-brand { display: grid; gap: 14px; align-content: start; }

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.footer-mark {
  display: grid;
  place-items: center;
  flex: none;
  min-width: 42px;
  height: 34px;
  padding: 0 8px;
  border-radius: 9px 4px 9px 4px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 800;
  color: #0B0714;
  background: linear-gradient(135deg, var(--c-cyan), var(--c-violet) 74%);
}

.footer-logo-text {
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0.01em;
}

.footer-line {
  max-width: 30ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-paper-2);
}

.footer-version {
  justify-self: start;
  padding: 5px 12px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(255, 209, 102, 0.3);
  background: rgba(255, 209, 102, 0.06);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--c-gold);
}

.footer-col {
  display: grid;
  gap: 12px;
  align-content: start;
}

.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-gold);
}

.footer-col-title::after {
  content: "";
  display: block;
  width: 22px;
  height: 2px;
  margin-top: 8px;
  background: linear-gradient(90deg, var(--c-violet), var(--c-cyan));
  opacity: 0.8;
}

.footer-list { display: grid; gap: 8px; }

.footer-link {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-paper-2);
  word-break: break-word;
  transition: color var(--dur) var(--ease);
}

a.footer-link:hover { color: var(--c-cyan); }

.footer-contact .footer-list { margin-bottom: 2px; }

.footer-addr,
.footer-note {
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--c-paper-3);
}

.footer-note { border-left: 2px solid var(--c-line-v); padding-left: 10px; }

.footer-base {
  width: var(--shell);
  margin-inline: auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  padding: 18px 0 28px;
  border-top: 1px solid var(--c-line-0);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--c-paper-3);
}

.footer-copy,
.footer-meta { max-width: none; }

/* ---------- 17. 进入视口显现协议 ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.52s var(--ease), transform 0.52s var(--ease);
}

.js [data-reveal="in"] {
  opacity: 1;
  transform: none;
}

/* ---------- 18. 响应式 ---------- */
@media (max-width: 1040px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  .grid--3,
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .brand-tagline { display: none; }
  .version-badge { padding: 5px 10px; font-size: 10.5px; letter-spacing: 0.06em; }
  .nav-toggle { padding: 9px 12px; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-base { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 420px) {
  .nav-toggle-label { display: none; }
  .brand-mark { min-width: 42px; height: 36px; font-size: 14px; }
}

/* 桌面：左侧常驻索引轨道 */
@media (min-width: 980px) {
  body { padding-left: var(--rail-w); }

  .site-header::after { display: none; }

  .site-nav {
    top: 0;
    right: auto;
    left: 0;
    bottom: 0;
    width: var(--rail-w);
    padding: 24px 16px 26px;
    border-left: 0;
    border-right: 1px solid var(--c-line-v);
    background: linear-gradient(180deg, #16112A, #0A0616 64%);
    box-shadow: none;
    transform: none;
    visibility: visible;
    transition: none;
    z-index: 96;
  }

  .site-nav::before {
    content: "";
    position: absolute;
    top: 0;
    left: 16px;
    right: 16px;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--c-violet), var(--c-cyan), transparent);
    opacity: 0.6;
  }

  .nav-toggle { display: none; }

  .command-bar { padding-inline: clamp(20px, 3vw, 40px); }
}

/* ---------- 19. 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .js [data-reveal],
  .js [data-reveal="in"] {
    opacity: 1;
    transform: none;
  }

  .site-nav { transition: none; }
  .scroll-progress-bar { transition: none; }
}