/* =============================================================
   KAIYUN赛场 · 共享样式 /assets/site.css
   夜光蓝底 + 荧光青 + 跑道橙 · 72px 侧轨导航 · 纸张叠层卡片
   ============================================================= */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--topbar-h) + 12px);
}

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

ul, ol { list-style: none; }
img, svg, video { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
hr { border: 0; border-top: 1px solid var(--edge); margin: 0; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --c-void:   #050A18;
  --c-arena:  #0B1730;
  --c-panel:  #131F3A;
  --c-steel:  #263A5F;
  --c-cyan:   #3DF0D0;
  --c-orange: #FF6A2C;
  --c-lime:   #FFD84D;
  --c-chalk:  #F3F7FF;
  --c-ash:    #93A4C4;
  --c-paper:  #F5F0E4;

  --bg: var(--c-void);
  --ink: var(--c-chalk);
  --dim: var(--c-ash);
  --edge: var(--c-steel);
  --accent: var(--c-cyan);

  --rail-w: 72px;
  --topbar-h: 60px;
  --wrap: 1200px;
  --pad: clamp(16px, 3vw, 40px);

  --f-head: "Noto Sans SC", "Source Han Sans SC", "PingFang SC",
            "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --f-body: var(--f-head);
  --f-mono: ui-monospace, "JetBrains Mono", "IBM Plex Mono", "SFMono-Regular",
            Menlo, Consolas, monospace;

  --ease: cubic-bezier(.2, .7, .3, 1);
  --r-sm: 6px;
  --r-md: 10px;
  --r-lg: 14px;
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--f-body);
  font-size: 1rem;
  line-height: 1.8;
  letter-spacing: .01em;
  color: var(--ink);
  background-color: var(--bg);
  background-image:
    radial-gradient(900px 620px at 88% -10%, rgba(61, 240, 208, .10), transparent 62%),
    radial-gradient(760px 540px at -8% 14%, rgba(255, 106, 44, .08), transparent 60%),
    linear-gradient(180deg, #050A18 0%, #060D1F 55%, #050A18 100%);
  background-attachment: fixed;
  min-height: 100vh;
  min-height: 100dvh;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--f-head);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--c-chalk);
}
h1 { font-size: clamp(2.2rem, 5vw, 4rem); }
h2 { font-size: clamp(1.4rem, 2.4vw, 2rem); }
h3 { font-size: clamp(1.05rem, 1.6vw, 1.3rem); }
h4 { font-size: 1rem; letter-spacing: -.01em; }

p { text-wrap: pretty; }

::selection { background: var(--c-cyan); color: #04161A; }

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

/* 桌面端为侧轨让位 */
@media (min-width: 1024px) {
  body { padding-inline-start: var(--rail-w); }
}

/* ---------- 4. 布局工具 ---------- */
.wrap {
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.section { padding-block: clamp(36px, 6vw, 80px); }
.section--tight { padding-block: clamp(20px, 3vw, 36px); }

.section__head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: clamp(18px, 2.4vw, 30px);
  flex-wrap: wrap;
}
.section__head::before {
  content: "";
  flex: 0 0 auto;
  width: clamp(24px, 4vw, 44px);
  height: 3px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--c-cyan), rgba(61, 240, 208, 0));
}
.section__title { margin: 0; }
.section__sub {
  color: var(--dim);
  font-size: .84rem;
  letter-spacing: .04em;
  margin-inline-start: auto;
}

.grid { display: grid; gap: clamp(12px, 1.6vw, 20px); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }

.prose { color: var(--c-chalk); }
.prose p { max-width: 38em; margin-block: 0 1em; }
.prose p:last-child { margin-bottom: 0; }
.prose a {
  color: var(--c-cyan);
  border-bottom: 1px solid rgba(61, 240, 208, .45);
}
.prose a:hover { border-bottom-color: var(--c-cyan); }

.mono {
  font-family: var(--f-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
}

.stat {
  display: block;
  font-family: var(--f-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.6rem, 3vw, 3rem);
  line-height: 1;
  color: var(--c-lime);
  letter-spacing: -.02em;
}
.stat-label {
  display: block;
  font-family: var(--f-mono);
  font-size: .68rem;
  letter-spacing: .18em;
  color: var(--dim);
  margin-top: 8px;
}

.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. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 8px;
  inset-inline-start: 8px;
  z-index: 300;
  padding: .6em 1em;
  border-radius: var(--r-md);
  background: var(--c-cyan);
  color: #04161A;
  font-weight: 700;
  font-size: .84rem;
  letter-spacing: .06em;
  transform: translateY(-220%);
  transition: transform .18s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5em;
  padding: .74em 1.24em;
  border: 1px solid var(--edge);
  border-radius: var(--r-md);
  background: var(--c-panel);
  color: var(--ink);
  font-family: var(--f-head);
  font-weight: 700;
  font-size: .86rem;
  letter-spacing: .06em;
  text-align: center;
  transition:
    border-color .18s var(--ease),
    background-color .18s var(--ease),
    color .18s var(--ease),
    transform .18s var(--ease);
}
.btn:hover { border-color: var(--c-cyan); color: var(--c-cyan); }
.btn:active { transform: translateY(1px); }

.btn--solid {
  background: var(--c-cyan);
  border-color: transparent;
  color: #03231E;
}
.btn--solid:hover { background: #7FFBE6; color: #03231E; }

.btn--warm {
  background: var(--c-orange);
  border-color: transparent;
  color: #1B0A02;
}
.btn--warm:hover { background: #FF8A55; color: #1B0A02; }

.btn--line { background: transparent; }

/* ---------- 7. 侧轨头部 ---------- */
.rail {
  position: fixed;
  inset-block: 0;
  inset-inline-start: 0;
  z-index: 80;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  background: linear-gradient(180deg, #0A1630 0%, #060C1E 100%);
  border-inline-end: 1px solid var(--edge);
}

.rail__inner {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  min-height: 0;
  height: 100%;
}

/* 品牌 */
.rail__brand {
  display: flex;
  justify-content: center;
  padding: 16px 6px 12px;
  border-bottom: 1px solid rgba(38, 58, 95, .7);
}
.brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
}
.brand__mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: linear-gradient(140deg, #3DF0D0, #14B8A6);
  color: #04161A;
  font-family: var(--f-mono);
  font-weight: 700;
  font-size: .72rem;
  letter-spacing: .04em;
  box-shadow: 0 0 0 1px rgba(61, 240, 208, .38), 0 8px 20px -12px rgba(61, 240, 208, .9);
}
.brand__text {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}
.brand__name {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-family: var(--f-head);
  font-weight: 800;
  line-height: 1.05;
}
.brand__name-lat {
  font-size: .6rem;
  letter-spacing: .1em;
  color: var(--c-chalk);
}
.brand__name-cjk {
  font-size: .74rem;
  letter-spacing: .16em;
  color: var(--c-chalk);
}
.brand__ver {
  font-family: var(--f-mono);
  font-size: .58rem;
  letter-spacing: .12em;
  line-height: 1.6;
  padding: 0 5px;
  border-radius: 4px;
  border: 1px solid rgba(255, 216, 77, .38);
  color: var(--c-lime);
}

/* 抽屉容器（桌面端为纵向列） */
.rail__drawer {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  min-height: 0;
}

/* 竖排导航 */
.rail__nav {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 12px 0;
  scrollbar-width: thin;
}
.rail__nav::-webkit-scrollbar { width: 3px; }
.rail__nav::-webkit-scrollbar-thumb {
  background: rgba(38, 58, 95, .9);
  border-radius: 3px;
}

.rail__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
}

.rail__link {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  margin-inline: auto;
  padding: 12px 0;
  border-radius: 9px;
  color: var(--dim);
  transition: color .18s var(--ease), background-color .18s var(--ease);
}
.rail__link::before {
  content: "";
  position: absolute;
  inset-inline-start: 3px;
  top: 50%;
  translate: 0 -50%;
  width: 3px;
  height: 0;
  border-radius: 2px;
  background: var(--c-cyan);
  transition: height .2s var(--ease);
}
.rail__label {
  writing-mode: vertical-rl;
  font-family: var(--f-head);
  font-size: .72rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: .16em;
}
.rail__link:hover {
  color: var(--ink);
  background: rgba(61, 240, 208, .07);
}
.rail__link:hover::before { height: 16px; }
.rail__link[aria-current="page"] {
  color: var(--c-cyan);
  background: rgba(61, 240, 208, .10);
}
.rail__link[aria-current="page"]::before { height: 28px; }

/* 轨道底部行动入口 */
.rail__actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 12px 6px 16px;
  border-top: 1px solid rgba(38, 58, 95, .7);
}
.rail__actions .btn {
  display: block;
  width: 100%;
  writing-mode: vertical-rl;
  padding: 14px 0;
  font-size: .7rem;
  line-height: 1.2;
  letter-spacing: .2em;
  border-radius: 9px;
}

/* 进度计 */
.rail__meter {
  position: absolute;
  inset-inline-end: -1px;
  inset-block: 0;
  width: 2px;
  pointer-events: none;
}
.rail__meter-fill {
  display: block;
  width: 100%;
  height: var(--p, 0%);
  background: linear-gradient(180deg, var(--c-cyan), var(--c-orange));
  transition: height .12s linear;
}

/* 移动端开关 */
.rail__toggle { display: none; }

/* ---------- 8. 移动端头部（≤1023px） ---------- */
@media (max-width: 1023px) {
  .rail {
    position: sticky;
    top: 0;
    inset-inline-start: auto;
    width: 100%;
    height: var(--topbar-h);
    flex-direction: row;
    border-inline-end: 0;
    border-bottom: 1px solid var(--edge);
    background: linear-gradient(180deg, rgba(11, 23, 48, .96), rgba(5, 10, 24, .94));
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
  }
  .rail__inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    width: 100%;
    height: 100%;
    padding-inline: 14px;
  }
  .rail__brand {
    padding: 0;
    border-bottom: 0;
  }
  .brand { flex-direction: row; gap: 9px; text-align: start; }
  .brand__mark { width: 30px; height: 30px; border-radius: 8px; font-size: .66rem; }
  .brand__text { flex-direction: row; align-items: center; gap: 7px; }
  .brand__name { flex-direction: row; align-items: baseline; gap: .34em; }
  .brand__name-lat { font-size: .74rem; letter-spacing: .1em; }
  .brand__name-cjk { font-size: .88rem; letter-spacing: .08em; }
  .brand__ver { font-size: .6rem; }

  .rail__drawer {
    position: fixed;
    inset-block-start: var(--topbar-h);
    inset-inline: 0;
    max-height: calc(100dvh - var(--topbar-h));
    overflow-y: auto;
    overscroll-behavior: contain;
    padding: 14px var(--pad) 26px;
    background: linear-gradient(180deg, #0B1730 0%, #050A18 100%);
    border-bottom: 1px solid var(--edge);
    box-shadow: 0 26px 50px -24px rgba(0, 0, 0, .9);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-12px);
    transition: opacity .2s var(--ease), transform .2s var(--ease), visibility .2s linear;
    z-index: 70;
  }
  .rail[data-open] .rail__drawer {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .rail__nav { overflow: visible; padding: 0; }
  .rail__list { align-items: stretch; gap: 2px; }
  .rail__link {
    width: auto;
    margin: 0;
    justify-content: flex-start;
    padding: 12px 14px;
    border-radius: var(--r-md);
    border: 1px solid transparent;
  }
  .rail__link::before { display: none; }
  .rail__link:hover { border-color: rgba(61, 240, 208, .28); }
  .rail__link[aria-current="page"] { border-color: rgba(61, 240, 208, .45); }
  .rail__label {
    writing-mode: horizontal-tb;
    font-size: .96rem;
    letter-spacing: .06em;
  }

  .rail__actions {
    flex-direction: row;
    align-items: stretch;
    gap: 10px;
    margin-top: 16px;
    padding: 16px 0 0;
  }
  .rail__actions .btn {
    flex: 1 1 0;
    width: auto;
    writing-mode: horizontal-tb;
    padding: .82em 1em;
    font-size: .84rem;
    letter-spacing: .06em;
  }

  .rail__meter {
    inset-inline: 0;
    inset-block: auto 0;
    width: auto;
    height: 2px;
  }
  .rail__meter-fill {
    width: var(--p, 0%);
    height: 100%;
    background: linear-gradient(90deg, var(--c-cyan), var(--c-orange));
    transition: width .12s linear;
  }

  .rail__toggle {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    border: 1px solid var(--edge);
    border-radius: 999px;
    background: var(--c-panel);
    color: var(--ink);
    font-family: var(--f-head);
    font-weight: 700;
    font-size: .76rem;
    letter-spacing: .1em;
    transition: border-color .18s var(--ease), color .18s var(--ease);
  }
  .rail__toggle[aria-expanded="true"] {
    border-color: var(--c-cyan);
    color: var(--c-cyan);
  }
  .rail__toggle-text { line-height: 1; }
  .rail__bars {
    display: flex;
    flex-direction: column;
    gap: 3px;
    width: 16px;
  }
  .rail__bars i {
    display: block;
    height: 2px;
    border-radius: 2px;
    background: currentColor;
    transition: transform .2s var(--ease), opacity .2s var(--ease);
  }
  .rail__toggle[aria-expanded="true"] .rail__bars i:nth-child(1) { transform: translateY(5px) rotate(45deg); }
  .rail__toggle[aria-expanded="true"] .rail__bars i:nth-child(2) { opacity: 0; }
  .rail__toggle[aria-expanded="true"] .rail__bars i:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }
}

/* ---------- 9. 页脚 ---------- */
.foot {
  position: relative;
  margin-top: clamp(48px, 8vw, 110px);
  background: linear-gradient(180deg, #0B1730 0%, #070D1E 100%);
  border-top: 1px solid var(--edge);
  overflow: hidden;
}
.foot::before {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--c-cyan) 0%, var(--c-orange) 46%, transparent 92%);
}
.foot::after {
  content: "";
  position: absolute;
  inset-block-start: -120px;
  inset-inline-end: -140px;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(61, 240, 208, .12), transparent 68%);
  pointer-events: none;
}

.foot__inner {
  position: relative;
  z-index: 1;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: clamp(32px, 5vw, 64px) var(--pad) 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3vw, 38px);
}

.foot__brandcol { max-width: 320px; }
.brand--foot {
  flex-direction: row;
  align-items: center;
  gap: 10px;
  text-align: start;
}
.brand--foot .brand__text { flex-direction: row; align-items: center; gap: 8px; }
.brand--foot .brand__name { flex-direction: row; align-items: baseline; gap: .34em; }
.brand--foot .brand__name-lat { font-size: .8rem; letter-spacing: .12em; }
.brand--foot .brand__name-cjk { font-size: .96rem; letter-spacing: .1em; }
.brand--foot .brand__ver { font-size: .62rem; }

.foot__tagline {
  margin-top: 16px;
  font-family: var(--f-head);
  font-weight: 700;
  font-size: .94rem;
  color: var(--c-chalk);
  letter-spacing: .04em;
}
.foot__metaline {
  margin-top: 10px;
  font-size: .8rem;
  color: var(--dim);
  line-height: 1.7;
}
.foot__metaline .mono { color: var(--c-lime); }

.foot__head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-family: var(--f-mono);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .22em;
  color: var(--c-ash);
}
.foot__head::after {
  content: "";
  flex: 1 1 auto;
  height: 1px;
  background: linear-gradient(90deg, var(--edge), transparent);
}

.foot__col a {
  display: inline-block;
  padding: 5px 0;
  font-size: .92rem;
  color: var(--ink);
  border-bottom: 1px solid transparent;
  transition: color .16s var(--ease), border-color .16s var(--ease);
}
.foot__col a:hover {
  color: var(--c-cyan);
  border-bottom-color: var(--c-cyan);
}

.foot__info li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  padding: 6px 0;
  font-size: .84rem;
  line-height: 1.6;
}
.foot__tag {
  flex: 0 0 auto;
  font-family: var(--f-mono);
  font-size: .6rem;
  letter-spacing: .14em;
  line-height: 1.9;
  padding: 0 6px;
  border-radius: 4px;
  border: 1px solid rgba(255, 106, 44, .42);
  color: var(--c-orange);
}
.foot__val { color: var(--c-chalk); word-break: break-all; }
.foot__note {
  margin-top: 12px;
  font-size: .76rem;
  line-height: 1.75;
  color: var(--dim);
  border-inline-start: 2px solid rgba(61, 240, 208, .4);
  padding-inline-start: 10px;
}

/* 纸张米白备案条 */
.foot__base {
  position: relative;
  z-index: 1;
  margin-top: clamp(28px, 4vw, 56px);
  background: var(--c-paper);
  color: #0B1730;
  border-top: 1px solid #DCD3BD;
}
.foot__base-inner {
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 16px var(--pad);
  padding-bottom: calc(16px + env(safe-area-inset-bottom, 0px));
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 22px;
  font-family: var(--f-mono);
  font-size: .74rem;
  letter-spacing: .04em;
}
.foot__base-inner span { white-space: nowrap; }

@media (min-width: 768px) {
  .foot__inner { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .foot__brandcol { grid-column: 1 / -1; max-width: none; }
}
@media (min-width: 1024px) {
  .foot__inner {
    grid-template-columns: minmax(200px, 1.15fr) repeat(4, minmax(0, .78fr)) minmax(190px, 1.25fr);
  }
  .foot__brandcol { grid-column: auto; max-width: 300px; }
}

/* ---------- 10. 通用组件 ---------- */
.panel {
  position: relative;
  padding: clamp(16px, 2.2vw, 26px);
  border: 1px solid var(--edge);
  border-radius: var(--r-lg);
  background: linear-gradient(180deg, rgba(19, 31, 58, .94), rgba(11, 23, 48, .94));
  transition: border-color .18s var(--ease), transform .18s var(--ease);
}
.panel:hover { border-color: rgba(61, 240, 208, .5); }

.paper-card {
  position: relative;
  padding: clamp(16px, 2.2vw, 26px);
  border: 1px solid #E3DAC4;
  border-radius: var(--r-lg);
  background: var(--c-paper);
  color: #0B1730;
  box-shadow:
    6px 6px 0 rgba(61, 240, 208, .22),
    12px 12px 0 rgba(255, 106, 44, .12);
}
.paper-card h2,
.paper-card h3 { color: #0B1730; }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  border-radius: 5px;
  border: 1px solid currentColor;
  font-family: var(--f-mono);
  font-size: .66rem;
  font-weight: 600;
  letter-spacing: .14em;
  line-height: 1.6;
  color: var(--c-ash);
  white-space: nowrap;
}
.tag--cyan { color: var(--c-cyan); background: rgba(61, 240, 208, .08); }
.tag--orange { color: var(--c-orange); background: rgba(255, 106, 44, .08); }
.tag--lime { color: var(--c-lime); background: rgba(255, 216, 77, .08); }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: 20px;
  font-family: var(--f-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--dim);
}
.breadcrumb li { display: flex; align-items: center; gap: 8px; }
.breadcrumb li + li::before {
  content: "/";
  color: var(--c-steel);
}
.breadcrumb a { transition: color .16s var(--ease); }
.breadcrumb a:hover { color: var(--c-cyan); }
.breadcrumb [aria-current="page"] { color: var(--c-chalk); }

/* 图片容器（供页面阶段放置图片占位） */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid var(--edge);
  border-radius: var(--r-lg);
  aspect-ratio: 16 / 10;
  background:
    linear-gradient(150deg, rgba(61, 240, 208, .16), transparent 56%),
    linear-gradient(205deg, rgba(255, 106, 44, .14), transparent 62%),
    var(--c-panel);
}
.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .45s var(--ease), opacity .3s var(--ease);
}
.media-frame:hover > img { transform: scale(1.02); }
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame__cap {
  position: absolute;
  inset-inline: 10px;
  inset-block-end: 10px;
  padding: 4px 9px;
  border: 1px solid var(--edge);
  border-radius: var(--r-sm);
  background: rgba(5, 10, 24, .74);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  font-family: var(--f-mono);
  font-size: .66rem;
  letter-spacing: .1em;
  color: var(--c-chalk);
}
.media-frame__flag {
  position: absolute;
  inset-block-start: 10px;
  inset-inline-start: 10px;
  padding: 3px 8px;
  border-radius: 5px;
  background: rgba(5, 10, 24, .78);
  border: 1px solid rgba(255, 216, 77, .45);
  font-family: var(--f-mono);
  font-size: .64rem;
  letter-spacing: .14em;
  color: var(--c-lime);
}

/* ---------- 11. 进入视口显现 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .5s var(--ease), transform .5s var(--ease);
}
[data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* ---------- 12. 减弱动效 ---------- */
@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;
  }
  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
}