/* ============================================================
   FG电子狂欢 · 中国站 共享样式 /assets/site.css
   体系：午夜电子控制台 + 粗野主义海报
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

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

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

img, svg, video, canvas { display: block; max-width: 100%; height: auto; }

button, input, select, textarea { font: inherit; color: inherit; }

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

table { border-collapse: collapse; }

summary { cursor: pointer; }

/* ---------- 2. Tokens ---------- */
:root {
  /* 色彩 */
  --violet: #7B3BFF;
  --indigo: #0B0620;
  --void: #05030F;
  --cyan: #22E0FF;
  --magenta: #FF2E9A;
  --yellow: #FFE44D;
  --mist: #C9B7FF;
  --slate: #6B5FA8;
  --panel: #1A1035;
  --offwhite: #F4F1FF;

  /* 布局 */
  --rail-w: 272px;
  --header-h: 68px;
  --gutter: clamp(18px, 4vw, 56px);
  --maxw: 1240px;

  /* 字体 */
  --font-poster: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  --font-display: "Songti SC", "STSong", "Source Han Serif SC",
    "Noto Serif SC", "SimSun", Georgia, serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;

  /* 描边与阴影 */
  --line: rgba(123, 59, 255, .45);
  --line-strong: rgba(123, 59, 255, .75);
  --hard-shadow: 8px 8px 0 rgba(5, 3, 15, .72);
  --glow-violet: 0 0 24px rgba(123, 59, 255, .55);
  --glow-cyan: 0 0 20px rgba(34, 224, 255, .6);
}

/* ---------- 3. 页面基底 ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail-w);
  color: var(--offwhite);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  background-color: var(--indigo);
  background-image:
    radial-gradient(1100px 620px at 84% -8%, rgba(123, 59, 255, .38), transparent 62%),
    radial-gradient(880px 520px at 12% 108%, rgba(255, 46, 154, .16), transparent 66%),
    linear-gradient(180deg, #140A31 0%, var(--indigo) 40%, var(--void) 100%);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

body.nav-open { overflow: hidden; }

@media (min-width: 1025px) {
  body { background-attachment: fixed; }
}

::selection {
  background: rgba(34, 224, 255, .35);
  color: #fff;
}

/* ---------- 4. 焦点与可达性 ---------- */
:focus-visible {
  outline: 3px solid var(--cyan);
  outline-offset: 3px;
}

:focus:not(:focus-visible) { outline: none; }

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

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 12px 18px;
  background: var(--cyan);
  color: var(--void);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  border: 2px solid var(--void);
  box-shadow: 5px 5px 0 rgba(123, 59, 255, .8);
  transform: translateY(-180%);
  transition: transform .2s ease;
}

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

/* ---------- 5. 侧边轨道导航 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--rail-w);
  z-index: 80;
}

.rail {
  position: relative;
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: 26px 22px 22px;
  background:
    linear-gradient(180deg, rgba(26, 16, 53, .94) 0%, rgba(11, 6, 32, .96) 52%, rgba(5, 3, 15, .98) 100%);
  border-right: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

.rail::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 1px;
  height: 100%;
  background: repeating-linear-gradient(
    180deg,
    rgba(34, 224, 255, .85) 0 2px,
    transparent 2px 14px
  );
  opacity: .45;
  pointer-events: none;
}

.rail__brand {
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(107, 95, 168, .42);
}

.brand {
  display: flex;
  align-items: center;
  gap: 13px;
}

.brand__mark {
  flex: 0 0 48px;
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  font-family: var(--font-poster);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: -.04em;
  color: #fff;
  background: linear-gradient(135deg, var(--violet), var(--magenta));
  border: 2px solid rgba(34, 224, 255, .55);
  box-shadow: 5px 5px 0 rgba(5, 3, 15, .9), var(--glow-violet);
  clip-path: polygon(0 0, 100% 0, 100% 72%, 74% 100%, 0 100%);
  transition: box-shadow .2s ease, transform .2s ease;
}

.brand:hover .brand__mark,
.brand:focus-visible .brand__mark {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 rgba(5, 3, 15, .9), 0 0 26px rgba(34, 224, 255, .7);
}

.brand__text { min-width: 0; }

.brand__name {
  display: block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 20px;
  line-height: 1.2;
  letter-spacing: -.01em;
  text-shadow: 0 0 16px rgba(123, 59, 255, .8);
}

.brand__sub {
  display: block;
  margin-top: 2px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--mist);
  opacity: .85;
}

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 10px 14px;
  background: rgba(26, 16, 53, .8);
  border: 2px solid var(--line-strong);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  cursor: pointer;
}

.nav-toggle__bars,
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--cyan);
  transition: transform .2s ease, background .2s ease, top .2s ease;
}

.nav-toggle__bars { position: relative; }

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
}

.nav-toggle__bars::before { top: -7px; }
.nav-toggle__bars::after { top: 7px; }

.site-header[data-open] .nav-toggle__bars { background: transparent; }

.site-header[data-open] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }

.site-header[data-open] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

/* 导航主体 */
.site-nav {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  min-height: 0;
  margin-top: 22px;
}

.site-nav__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.site-nav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 11px 12px 11px 14px;
  border-left: 2px solid transparent;
  border-radius: 0 2px 2px 0;
  color: rgba(244, 241, 255, .74);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .02em;
  transition: color .2s ease, background .2s ease, border-color .2s ease, transform .2s ease;
}

.site-nav__link:hover,
.site-nav__link:focus-visible {
  color: #fff;
  background: linear-gradient(90deg, rgba(123, 59, 255, .34), rgba(123, 59, 255, 0));
  border-left-color: var(--magenta);
  transform: translateX(4px);
}

.site-nav__link[aria-current="page"] {
  color: #fff;
  border-left-color: var(--cyan);
  background: linear-gradient(90deg, rgba(34, 224, 255, .2), rgba(34, 224, 255, 0));
  box-shadow: inset 0 0 0 1px rgba(34, 224, 255, .14);
}

.site-nav__num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  color: var(--slate);
  transition: color .2s ease;
}

.site-nav__link:hover .site-nav__num { color: var(--magenta); }

.site-nav__link[aria-current="page"] .site-nav__num {
  color: var(--cyan);
  text-shadow: var(--glow-cyan);
}

/* 轨道底部面板 */
.rail__panel {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px solid rgba(107, 95, 168, .42);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.rail__search {
  display: block;
  padding: 11px 13px;
  border: 1px dashed rgba(34, 224, 255, .45);
  background: rgba(34, 224, 255, .06);
  transition: background .2s ease, border-color .2s ease, border-style .2s ease;
}

.rail__search:hover,
.rail__search:focus-visible {
  border-style: solid;
  border-color: var(--cyan);
  background: rgba(34, 224, 255, .14);
}

.rail__search-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.rail__search-hint {
  display: block;
  margin-top: 2px;
  font-size: 12px;
  line-height: 1.5;
  color: rgba(244, 241, 255, .62);
}

.rail__actions {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.rail__status {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--slate);
}

.rail__dot {
  width: 8px;
  height: 8px;
  flex: 0 0 8px;
  background: var(--cyan);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--cyan);
  animation: railPulse 2.4s ease-in-out infinite;
}

@keyframes railPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: .35; }
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 18px;
  border: 2px solid var(--violet);
  border-radius: 2px;
  background: transparent;
  color: var(--offwhite);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .1em;
  text-align: center;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease,
    background .18s ease, border-color .18s ease, color .18s ease;
}

.btn--primary {
  background: linear-gradient(120deg, var(--cyan), #7fe6ff);
  border-color: var(--cyan);
  color: var(--void);
  box-shadow: 4px 4px 0 rgba(123, 59, 255, .6);
}

.btn--primary:hover,
.btn--primary:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 rgba(255, 46, 154, .55);
}

.btn--ghost {
  border-color: rgba(201, 183, 255, .5);
  color: var(--mist);
}

.btn--ghost:hover,
.btn--ghost:focus-visible {
  border-color: var(--magenta);
  background: rgba(255, 46, 154, .12);
  color: #fff;
}

.btn:active { transform: translate(0, 0); }

/* ---------- 7. 容器与骨架 ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
}

.page-shell {
  display: block;
  padding: clamp(30px, 5vw, 68px) var(--gutter) 0;
}

.page-shell:focus { outline: none; }

/* ---------- 8. 面包屑 ---------- */
.breadcrumb { margin-bottom: clamp(16px, 2.4vw, 28px); }

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: rgba(244, 241, 255, .55);
}

.breadcrumb__item:not(:last-child)::after {
  content: "/";
  margin-left: 8px;
  color: var(--slate);
}

.breadcrumb__link { transition: color .2s ease; }

.breadcrumb__link:hover,
.breadcrumb__link:focus-visible { color: var(--cyan); }

.breadcrumb__current { color: var(--mist); }

/* ---------- 9. 海报首屏 ---------- */
.poster {
  position: relative;
  isolation: isolate;
  padding: clamp(24px, 4vw, 48px) 0 clamp(30px, 5vw, 62px);
  overflow: hidden;
}

.poster__kicker {
  display: inline-block;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--magenta);
}

.poster__title {
  font-family: var(--font-poster);
  font-weight: 900;
  font-size: clamp(42px, 8.6vw, 118px);
  line-height: .95;
  letter-spacing: -.035em;
  text-shadow: 0 0 26px rgba(123, 59, 255, .75), 0 0 64px rgba(123, 59, 255, .32);
}

.poster__title em {
  font-style: normal;
  color: var(--cyan);
  text-shadow: 0 0 22px rgba(34, 224, 255, .75);
}

.poster__lead {
  max-width: 62ch;
  margin-top: 20px;
  color: rgba(244, 241, 255, .78);
  font-size: 16px;
}

.poster__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.lightband {
  position: absolute;
  left: -12%;
  right: -12%;
  height: 130px;
  z-index: -1;
  pointer-events: none;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(123, 59, 255, .45) 28%,
    rgba(34, 224, 255, .5) 54%,
    rgba(255, 46, 154, .42) 78%,
    transparent 100%
  );
  filter: blur(30px);
  animation: bandBreathe 7s ease-in-out infinite;
}

@keyframes bandBreathe {
  0%, 100% { opacity: .7; transform: translateY(0) rotate(-1.2deg); }
  50% { opacity: 1; transform: translateY(-8px) rotate(-0.4deg); }
}

/* ---------- 10. 章节与分隔 ---------- */
.section { margin-bottom: clamp(34px, 5vw, 72px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px 20px;
  margin-bottom: 22px;
}

.section__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--cyan);
  border: 1px solid rgba(34, 224, 255, .5);
  padding: 3px 8px;
}

.section__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 3.4vw, 44px);
  line-height: 1.14;
  letter-spacing: -.01em;
  border-left: 4px solid var(--cyan);
  padding-left: 14px;
}

.section__lead {
  flex: 1 1 300px;
  max-width: 58ch;
  font-size: 15px;
  color: rgba(244, 241, 255, .68);
}

.pulse-divider {
  position: relative;
  height: 2px;
  margin: clamp(26px, 4vw, 54px) 0;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 46, 154, .9) 12%,
    rgba(123, 59, 255, .9) 55%,
    transparent
  );
}

.pulse-divider::after {
  content: "";
  position: absolute;
  inset: -1px 0 auto 0;
  height: 4px;
  background: repeating-linear-gradient(
    90deg,
    rgba(34, 224, 255, .5) 0 6px,
    transparent 6px 15px
  );
}

/* ---------- 11. 网格、卡片 ---------- */
.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(258px, 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(206px, 1fr)); }

.waterfall {
  columns: 2;
  column-gap: clamp(16px, 2.4vw, 28px);
}

.waterfall > * {
  break-inside: avoid;
  margin-bottom: clamp(16px, 2.4vw, 28px);
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 22px 22px 24px;
  background: linear-gradient(160deg, rgba(26, 16, 53, .96), rgba(11, 6, 32, .96));
  border: 2px solid var(--line);
  box-shadow: var(--hard-shadow);
  transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease;
}

.card:hover,
.card:focus-within {
  transform: translate(-3px, -3px);
  border-color: rgba(34, 224, 255, .7);
  box-shadow: 12px 12px 0 rgba(123, 59, 255, .35);
}

.card--trace {
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.card--ledger { font-family: var(--font-mono); }

.card__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--magenta);
}

.card__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 22px;
  line-height: 1.3;
}

.card__body {
  font-size: 15px;
  color: rgba(244, 241, 255, .74);
}

.card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: auto;
  padding-top: 10px;
  border-top: 1px solid rgba(107, 95, 168, .38);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--slate);
}

.card__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 6px;
}

/* ---------- 12. 标签、提示 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border: 1px solid currentColor;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  line-height: 1.6;
}

.tag--cyan { color: var(--cyan); }
.tag--magenta { color: var(--magenta); }
.tag--yellow { color: var(--yellow); }

.note {
  padding: 13px 16px;
  border-left: 4px solid var(--violet);
  background: rgba(123, 59, 255, .12);
  font-size: 14px;
  color: rgba(244, 241, 255, .82);
}

.note--yellow {
  border-left-color: var(--yellow);
  background: rgba(255, 228, 77, .1);
  color: var(--yellow);
}

/* ---------- 13. 折叠面板 ---------- */
.fold {
  border: 2px solid var(--line);
  background: rgba(26, 16, 53, .72);
  transition: border-color .2s ease;
}

.fold:hover { border-color: rgba(34, 224, 255, .6); }

.fold__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 18px;
  font-weight: 600;
  font-size: 16px;
  list-style: none;
}

.fold__summary::-webkit-details-marker { display: none; }

.fold__summary::after {
  content: "＋";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  color: var(--cyan);
}

.fold[open] .fold__summary::after { content: "－"; }

.fold[open] .fold__summary { border-bottom: 1px solid rgba(107, 95, 168, .4); }

.fold__body {
  padding: 16px 18px 20px;
  font-size: 15px;
  color: rgba(244, 241, 255, .75);
}

.fold__meta {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--slate);
}

/* ---------- 14. 标签页 ---------- */
.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.tab {
  padding: 9px 18px;
  border: 1px solid rgba(201, 183, 255, .42);
  background: transparent;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  cursor: pointer;
  clip-path: polygon(9px 0, 100% 0, 100% 100%, 0 100%);
  transition: background .2s ease, color .2s ease, border-color .2s ease;
}

.tab:hover { background: rgba(123, 59, 255, .22); color: #fff; }

.tab[aria-selected="true"] {
  background: var(--violet);
  border-color: var(--cyan);
  color: #fff;
  box-shadow: 0 0 18px rgba(123, 59, 255, .55);
}

.tab-panel[hidden] { display: none; }

/* ---------- 15. 数字与表格 ---------- */
.stat {
  padding-left: 14px;
  border-left: 3px solid var(--magenta);
}

.stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.2;
  color: var(--cyan);
}

.stat__label {
  display: block;
  font-size: 13px;
  color: rgba(244, 241, 255, .65);
}

.price {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  font-family: var(--font-mono);
  color: var(--yellow);
}

.price__num {
  font-size: clamp(26px, 4vw, 42px);
  font-weight: 700;
  line-height: 1.1;
}

.price__unit {
  font-size: 13px;
  color: rgba(244, 241, 255, .6);
}

.table-wrap {
  overflow-x: auto;
  border: 2px solid var(--line);
  background: rgba(11, 6, 32, .6);
}

.spec-table {
  width: 100%;
  min-width: 540px;
  font-size: 14px;
}

.spec-table th,
.spec-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid rgba(107, 95, 168, .35);
  vertical-align: top;
}

.spec-table th {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--mist);
  background: rgba(26, 16, 53, .9);
}

.spec-table tr:last-child td { border-bottom: 0; }

.spec-table td.mono { color: var(--cyan); }

/* ---------- 16. 时间线 ---------- */
.timeline {
  position: relative;
  padding-left: 26px;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--violet), transparent);
}

.timeline__item {
  position: relative;
  padding: 0 0 28px 6px;
}

.timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 14px;
  height: 14px;
  background: var(--void);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
}

.timeline__item:last-child { padding-bottom: 0; }

.timeline__date {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--magenta);
}

.timeline__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 21px;
  line-height: 1.3;
  margin-top: 4px;
}

.timeline__text {
  font-size: 15px;
  color: rgba(244, 241, 255, .72);
}

/* ---------- 17. 图片容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border: 2px solid var(--line);
  background: linear-gradient(135deg, rgba(26, 16, 53, .95), rgba(5, 3, 15, .95));
  box-shadow: var(--hard-shadow);
}

.media-frame__inner {
  aspect-ratio: 16 / 9;
  width: 100%;
}

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

.media-frame--wide .media-frame__inner { aspect-ratio: 21 / 9; }
.media-frame--square .media-frame__inner { aspect-ratio: 1 / 1; }
.media-frame--tall .media-frame__inner { aspect-ratio: 3 / 4; }
.media-frame--thin .media-frame__inner { aspect-ratio: 32 / 9; }

.media-frame--empty .media-frame__inner {
  display: grid;
  place-items: center;
  background-image: repeating-linear-gradient(
    135deg,
    rgba(123, 59, 255, .22) 0 14px,
    rgba(34, 224, 255, .08) 14px 28px
  );
}

.media-frame--empty .media-frame__inner::after {
  content: "FG · MEDIA";
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  color: rgba(244, 241, 255, .5);
}

.media-frame__caption {
  display: block;
  padding: 10px 14px;
  border-top: 1px solid rgba(107, 95, 168, .4);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--slate);
}

/* ---------- 18. 复制按钮 ---------- */
.copy-btn {
  padding: 3px 8px;
  border: 1px solid rgba(34, 224, 255, .5);
  background: transparent;
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background .18s ease, border-color .18s ease, color .18s ease;
}

.copy-btn:hover,
.copy-btn:focus-visible { background: rgba(34, 224, 255, .16); }

.copy-btn.is-copied {
  border-color: var(--yellow);
  color: var(--yellow);
  background: rgba(255, 228, 77, .12);
}

/* ---------- 19. 滚动进度与回到顶部 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: var(--rail-w);
  right: 0;
  height: 3px;
  z-index: 90;
  pointer-events: none;
}

.scroll-progress__bar {
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--cyan), var(--violet), var(--magenta));
  box-shadow: 0 0 14px rgba(34, 224, 255, .75);
}

.to-top {
  position: fixed;
  right: clamp(14px, 2vw, 28px);
  bottom: clamp(14px, 2vw, 28px);
  z-index: 70;
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  padding: 0;
  background: rgba(26, 16, 53, .94);
  border: 2px solid var(--cyan);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .08em;
  cursor: pointer;
  box-shadow: 4px 4px 0 rgba(123, 59, 255, .5);
  opacity: 0;
  visibility: hidden;
  transition: opacity .2s ease, visibility .2s ease, transform .2s ease, background .2s ease;
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
}

.to-top:hover,
.to-top:focus-visible {
  transform: translate(-2px, -2px);
  background: rgba(34, 224, 255, .16);
}

/* ---------- 20. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 7vw, 110px);
  padding: clamp(44px, 6vw, 76px) var(--gutter) 26px;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(11, 6, 32, .55) 0%, var(--void) 72%);
  overflow: hidden;
}

.footer__glow {
  position: absolute;
  left: -10%;
  right: -10%;
  top: -80px;
  height: 180px;
  pointer-events: none;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(123, 59, 255, .5) 30%,
    rgba(34, 224, 255, .38) 62%,
    transparent
  );
  filter: blur(38px);
  opacity: .55;
}

.footer__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(230px, 1.5fr) repeat(3, minmax(128px, .85fr)) minmax(230px, 1.3fr);
  gap: clamp(24px, 3vw, 42px);
}

.footer__slogan {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(22px, 2.4vw, 30px);
  line-height: 1.24;
  letter-spacing: -.01em;
  text-shadow: 0 0 20px rgba(123, 59, 255, .65);
}

.footer__domain {
  margin-top: 10px;
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--cyan);
}

.footer__note {
  margin-top: 6px;
  font-size: 13px;
  color: rgba(244, 241, 255, .6);
}

.footer__nav {
  display: contents;
}

.footer__col-title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--magenta);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer__link {
  display: inline-block;
  font-size: 14px;
  color: rgba(244, 241, 255, .74);
  border-bottom: 1px solid transparent;
  transition: color .18s ease, border-color .18s ease, transform .18s ease;
}

.footer__link:hover,
.footer__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--magenta);
  transform: translateX(3px);
}

.footer__meta {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer__meta-row dt {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--slate);
}

.footer__meta-value {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: rgba(244, 241, 255, .82);
  word-break: break-word;
}

.site-footer .pulse-divider {
  margin: clamp(30px, 4vw, 52px) 0 clamp(18px, 2.4vw, 28px);
}

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 22px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--slate);
}

.footer__copy { color: rgba(244, 241, 255, .6); }

.footer__icp { color: var(--mist); }

.footer__service {
  flex: 1 1 260px;
  text-align: right;
  color: var(--slate);
}

/* ---------- 21. 工具类 ---------- */
.mono { font-family: var(--font-mono); }

.label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--mist);
}

.editorial {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -.01em;
}

.text-mist { color: var(--mist); }
.text-cyan { color: var(--cyan); }

/* ---------- 22. 响应式 ---------- */
@media (max-width: 1280px) {
  :root { --rail-w: 236px; }

  .footer__inner {
    grid-template-columns: minmax(200px, 1.4fr) repeat(3, minmax(112px, .8fr));
  }

  .footer__contact { grid-column: 1 / -1; }

  .footer__meta {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 12px 34px;
  }
}

@media (max-width: 1024px) {
  :root { --rail-w: 0px; }

  body {
    padding-left: 0;
    padding-top: var(--header-h);
  }

  .site-header {
    top: 0;
    left: 0;
    right: 0;
    bottom: auto;
    width: 100%;
    height: var(--header-h);
  }

  .rail {
    flex-direction: row;
    align-items: center;
    gap: 12px;
    height: var(--header-h);
    padding: 0 16px;
    border-right: 0;
    border-bottom: 1px solid var(--line-strong);
  }

  .rail::after { display: none; }

  .rail__brand {
    flex: 1 1 auto;
    min-width: 0;
    padding: 0;
    border-bottom: 0;
  }

  .brand__mark {
    flex-basis: 40px;
    width: 40px;
    height: 40px;
    font-size: 15px;
    box-shadow: 3px 3px 0 rgba(5, 3, 15, .9);
  }

  .brand__name { font-size: 17px; }

  .brand__sub { display: none; }

  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    bottom: 0;
    width: min(86vw, 344px);
    margin-top: 0;
    padding: 18px 16px 30px;
    overflow-y: auto;
    background: linear-gradient(180deg, rgba(26, 16, 53, .99), rgba(5, 3, 15, .99));
    border-right: 2px solid rgba(123, 59, 255, .6);
    box-shadow: 26px 0 60px rgba(5, 3, 15, .82);
    transform: translateX(-104%);
    visibility: hidden;
    transition: transform .28s cubic-bezier(.4, 0, .2, 1), visibility .28s;
  }

  .site-nav[data-open] {
    transform: translateX(0);
    visibility: visible;
  }

  .site-nav__link { padding: 14px 12px; font-size: 16px; }

  .rail__panel { margin-top: 26px; }

  .scroll-progress { left: 0; top: var(--header-h); }

  .footer__inner { grid-template-columns: repeat(2, minmax(140px, 1fr)); }

  .footer__brand { grid-column: 1 / -1; }

  .footer__service { text-align: left; }
}

@media (max-width: 640px) {
  body { font-size: 16px; }

  .poster__title { letter-spacing: -.02em; }

  .waterfall { columns: 1; }

  .footer__inner { grid-template-columns: 1fr; }

  .footer__legal { flex-direction: column; align-items: flex-start; gap: 6px; }

  .to-top {
    width: 48px;
    height: 48px;
  }
}

/* ---------- 23. 减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .lightband { animation: none; opacity: .8; }
  .rail__dot { animation: none; }
}