/* ==========================================================================
   澳门吉斯尼站 · 共享样式表 /assets/site.css
   视觉语言：澳门霓虹夜景 × 复古出版索引卡
   ========================================================================== */

/* ---------------------------------------------------------------- reset */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scrollbar-color: rgba(0, 229, 255, .35) #0B1B2B;
}

body,
h1, h2, h3, h4, p, ul, ol, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }

/* --------------------------------------------------------------- tokens */
:root {
  /* 品牌色 */
  --c-ink: #0B1B2B;      /* 深墨蓝 · 主背景 */
  --c-ink-2: #0E2136;
  --c-cyan: #00E5FF;     /* 电光青 · 强调 */
  --c-gold: #FFB74D;     /* 暖金 · 版本与标签 */
  --c-cream: #F3E9D7;    /* 奶油纸 · 索引卡 */
  --c-brown: #1C1410;    /* 深棕黑 · 纸上正文 */
  --c-orange: #FF5A36;   /* 霓虹红橙 · 点色 */
  --c-mist: #8FB8C6;     /* 雾青灰 · 次级 */
  --c-deep: #123D4A;     /* 深青蓝 · 中间层 */
  --c-violet: #2A1B3D;   /* 午夜紫 · 氛围 */
  --c-soft: #B8F6FF;     /* 浅霓虹青 · 高亮 */

  /* 语义 */
  --bg: var(--c-ink);
  --panel: rgba(18, 61, 74, .48);
  --panel-solid: var(--c-deep);
  --txt: #DCE7EE;
  --txt-strong: var(--c-cream);
  --txt-mute: var(--c-mist);
  --line: rgba(143, 184, 198, .24);
  --line-2: rgba(143, 184, 198, .44);
  --line-hot: rgba(0, 229, 255, .62);
  --line-gold: rgba(255, 183, 77, .55);

  /* 字体 */
  --font-sans: "Source Han Sans SC", "Noto Sans SC", "Source Han Sans CN",
    system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", ui-monospace, Menlo,
    Consolas, "Courier New", monospace;

  /* 尺寸 */
  --w: 1360px;
  --gutter: clamp(16px, 3.2vw, 44px);
  --hdr: 92px;

  /* 动效 */
  --t-fast: .14s ease;
  --t: .22s cubic-bezier(.2, .7, .3, 1);
}

/* ----------------------------------------------------------------- base */
body {
  min-height: 100vh;
  background-color: var(--bg);
  background-image:
    linear-gradient(rgba(143, 184, 198, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(143, 184, 198, .055) 1px, transparent 1px),
    radial-gradient(920px 540px at 84% -10%, rgba(0, 229, 255, .16), transparent 62%),
    radial-gradient(700px 460px at 2% 14%, rgba(42, 27, 61, .60), transparent 62%),
    linear-gradient(180deg, #0B1B2B 0%, #0A1930 48%, #0B1220 100%);
  background-size: 48px 48px, 48px 48px, auto, auto, auto;
  background-attachment: fixed, fixed, fixed, fixed, fixed;
  color: var(--txt);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 500;
  line-height: 1.8;
  letter-spacing: .01em;
}

h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--txt-strong);
}

h1 { font-size: clamp(34px, 5vw, 60px); }
h2 { font-size: clamp(26px, 3.4vw, 36px); }
h3 { font-size: clamp(20px, 2.3vw, 26px); }
h4 { font-size: 18px; }

::selection { background: rgba(0, 229, 255, .3); color: var(--c-cream); }

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

[id] { scroll-margin-top: calc(var(--hdr) + 18px); }

/* ------------------------------------------------------------ utilities */
.mono { font-family: var(--font-mono); letter-spacing: .06em; }
.muted { color: var(--txt-mute); }
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}
.divider {
  height: 1px;
  border: 0;
  margin: clamp(28px, 4vw, 52px) 0;
  background: linear-gradient(90deg, var(--line-2), transparent 72%);
}

/* ------------------------------------------------------------- skip link */
.skip-link {
  position: absolute;
  left: 12px;
  top: -120px;
  z-index: 200;
  padding: 12px 20px;
  background: var(--c-cyan);
  color: #03222B;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .08em;
  border: 1px solid #03222B;
  transition: top var(--t);
}
.skip-link:focus { top: 12px; }

/* --------------------------------------------------------------- header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: linear-gradient(180deg,
    rgba(11, 27, 43, .96) 0%,
    rgba(11, 27, 43, .82) 62%,
    rgba(11, 27, 43, 0) 100%);
  -webkit-backdrop-filter: blur(9px);
  backdrop-filter: blur(9px);
}
.site-header::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, var(--c-cyan), rgba(255, 183, 77, .6) 42%, transparent 88%);
  opacity: .85;
}

.scroll-progress {
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 2px;
  background: rgba(143, 184, 198, .12);
  overflow: hidden;
}
.scroll-progress-bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--c-cyan), var(--c-gold));
  transition: width .1s linear;
}

.header-shell {
  position: relative;
  width: 100%;
  max-width: var(--w);
  margin: 0 auto;
  padding: 14px var(--gutter) 16px;
  display: grid;
  grid-template-columns: auto minmax(280px, 1fr) auto;
  grid-template-areas: "brand anchor nav";
  align-items: center;
  gap: clamp(12px, 1.6vw, 22px);
}

/* ---------------------------------------------------------- brand island */
.brand-island {
  grid-area: brand;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 9px 18px 9px 12px;
  background: rgba(18, 61, 74, .62);
  border: 1px solid var(--line);
  border-left: 2px solid var(--c-cyan);
  transition: border-color var(--t), background var(--t);
}
.brand-island:hover { border-color: var(--line-hot); background: rgba(18, 61, 74, .85); }

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px; height: 38px;
  border: 1px solid var(--line-gold);
  background: rgba(255, 183, 77, .1);
  color: var(--c-gold);
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1;
}
.brand-text { display: block; }
.brand-name {
  display: block;
  font-size: 17px;
  font-weight: 700;
  color: var(--c-cream);
  letter-spacing: .02em;
  line-height: 1.35;
}
.brand-sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .24em;
  color: var(--c-mist);
  line-height: 1.4;
}

/* ------------------------------------------- 第二格 · 放大视觉锚点浮岛 */
.anchor-slot {
  grid-area: anchor;
  position: relative;
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 58px;
  padding: 8px 10px 8px 18px;
  border: 1px solid var(--line-gold);
  background:
    linear-gradient(90deg, rgba(255, 183, 77, .16), rgba(0, 229, 255, .07) 58%, rgba(0, 229, 255, 0) 100%),
    rgba(18, 61, 74, .5);
  transition: border-color var(--t), box-shadow var(--t);
}
.anchor-slot:hover,
.anchor-slot:focus-within {
  border-color: var(--c-gold);
  box-shadow: 0 0 0 1px rgba(255, 183, 77, .22), 0 14px 40px rgba(0, 0, 0, .38);
}
.anchor-index {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--c-gold);
  letter-spacing: -.02em;
  padding-right: 14px;
  border-right: 1px solid var(--line-gold);
}
.anchor-copy { display: grid; gap: 1px; min-width: 0; }
.anchor-label {
  font-size: 15px;
  font-weight: 700;
  color: var(--c-cream);
  letter-spacing: .04em;
}
.anchor-sub {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: rgba(0, 229, 255, .82);
}
.anchor-cta { margin-left: auto; }

.anchor-preview {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  width: 306px;
  padding: 14px 16px 12px;
  background: rgba(11, 27, 43, .98);
  border: 1px solid var(--line-hot);
  border-top: 2px solid var(--c-cyan);
  box-shadow: 0 26px 60px rgba(0, 0, 0, .62);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity var(--t), transform var(--t), visibility var(--t);
}
.anchor-slot:hover .anchor-preview,
.anchor-slot:focus-within .anchor-preview {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.anchor-preview-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--c-gold);
  padding-bottom: 8px;
  margin-bottom: 6px;
  border-bottom: 1px solid var(--line);
}
.anchor-preview-list { display: grid; gap: 1px; }
.anchor-preview-link {
  display: block;
  padding: 7px 8px;
  font-size: 14px;
  color: var(--txt-mute);
  border-left: 2px solid transparent;
  transition: color var(--t), border-color var(--t), background var(--t);
}
.anchor-preview-link:hover,
.anchor-preview-link:focus-visible {
  color: var(--c-soft);
  border-left-color: var(--c-cyan);
  background: rgba(0, 229, 255, .08);
}
.anchor-preview-note {
  margin-top: 8px;
  font-size: 11.5px;
  color: rgba(143, 184, 198, .72);
  line-height: 1.6;
}

/* ------------------------------------------------------ 悬浮胶囊导航 */
.nav-island {
  grid-area: nav;
  display: flex;
  justify-content: flex-end;
}
.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 5px;
  border: 1px solid var(--line);
  background: rgba(18, 61, 74, .55);
}
.nav-item { display: block; }
.nav-link {
  position: relative;
  display: block;
  padding: 9px 13px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .1em;
  white-space: nowrap;
  color: var(--txt-mute);
  border: 1px solid transparent;
  transition: color var(--t), border-color var(--t), background var(--t);
}
.nav-link:hover,
.nav-link:focus-visible {
  color: var(--c-cream);
  border-color: var(--line-hot);
  background: rgba(0, 229, 255, .08);
}
.nav-link[aria-current="page"] {
  color: var(--c-gold);
  border-color: var(--line-gold);
  background: rgba(255, 183, 77, .1);
}
.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 13px; right: 13px; bottom: 3px;
  height: 1px;
  background: linear-gradient(90deg, var(--c-gold), rgba(0, 229, 255, .8));
}

/* ----------------------------------------------------- 移动导航按钮 */
.nav-toggle {
  grid-area: toggle;
  display: none;
  align-items: center;
  gap: 10px;
  min-height: 48px;
  padding: 12px 16px;
  border: 1px solid var(--line-2);
  background: rgba(18, 61, 74, .62);
  color: var(--c-cream);
  cursor: pointer;
  transition: border-color var(--t), background var(--t);
}
.nav-toggle:hover { border-color: var(--line-hot); background: rgba(18, 61, 74, .9); }
.nav-toggle-box { display: grid; gap: 4px; width: 18px; }
.nav-toggle-bar {
  display: block;
  height: 2px;
  background: var(--c-cyan);
  transition: transform var(--t), opacity var(--t);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
.nav-toggle-text {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .18em;
}

/* --------------------------------------------------------------- footer */
.site-footer {
  margin-top: clamp(56px, 8vw, 108px);
  border-top: 1px solid var(--line-2);
  background:
    linear-gradient(180deg, rgba(18, 61, 74, .38) 0%, rgba(11, 27, 43, .92) 46%, #070F18 100%),
    linear-gradient(90deg, transparent 0%, rgba(42, 27, 61, .55) 100%);
  color: var(--txt);
}
.footer-shell {
  max-width: var(--w);
  margin: 0 auto;
  padding: clamp(36px, 5vw, 68px) var(--gutter) clamp(24px, 3vw, 36px);
  display: grid;
  grid-template-columns: minmax(250px, .9fr) 1.7fr;
  gap: clamp(28px, 4vw, 68px);
}
.footer-brand { display: grid; gap: 12px; align-content: start; }
.footer-brand-link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  width: fit-content;
}
.footer-brand-mark {
  display: grid;
  place-items: center;
  width: 36px; height: 36px;
  border: 1px solid var(--line-gold);
  background: rgba(255, 183, 77, .09);
  color: var(--c-gold);
  font-family: var(--font-mono);
  font-size: 14px;
}
.footer-brand-name {
  font-size: 19px;
  font-weight: 700;
  color: var(--c-cream);
  letter-spacing: .03em;
}
.footer-brand-link:hover .footer-brand-name { color: var(--c-soft); }
.footer-tagline {
  max-width: 30ch;
  font-size: 15px;
  color: var(--txt-mute);
  line-height: 1.8;
}
.footer-local {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: rgba(255, 183, 77, .85);
  padding-top: 6px;
  border-top: 1px dashed var(--line);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}
.footer-col { display: grid; gap: 12px; align-content: start; }
.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .22em;
  color: var(--c-gold);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}
.footer-list { display: grid; gap: 2px; }
.footer-link {
  display: block;
  padding: 6px 0;
  font-size: 14.5px;
  color: var(--txt-mute);
  border-bottom: 1px solid transparent;
  transition: color var(--t), border-color var(--t), padding-left var(--t);
}
.footer-link:hover,
.footer-link:focus-visible {
  color: var(--c-soft);
  border-bottom-color: var(--line-hot);
  padding-left: 6px;
}

.footer-base {
  max-width: var(--w);
  margin: 0 auto;
  padding: clamp(18px, 2.4vw, 28px) var(--gutter) clamp(24px, 3vw, 40px);
  border-top: 1px solid var(--line);
  display: grid;
  gap: 14px;
}
.footer-contact {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 32px;
  font-size: 13.5px;
  color: var(--txt-mute);
}
.contact-item { display: flex; flex-wrap: wrap; gap: 8px; align-items: baseline; }
.contact-key {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .2em;
  color: var(--c-cyan);
  border: 1px solid var(--line-hot);
  padding: 1px 6px;
}
.footer-hours {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: rgba(143, 184, 198, .85);
}
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 13px;
  color: rgba(143, 184, 198, .8);
}
.footer-copy { letter-spacing: .04em; }
.footer-icp {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--txt-mute);
}

/* -------------------------------------------------------------- buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid var(--line-2);
  background: rgba(18, 61, 74, .5);
  color: var(--c-cream);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .1em;
  white-space: nowrap;
  cursor: pointer;
  transition: color var(--t), border-color var(--t), background var(--t), box-shadow var(--t);
}
.btn:hover,
.btn:focus-visible {
  border-color: var(--line-hot);
  color: var(--c-soft);
  box-shadow: inset 0 0 0 1px rgba(0, 229, 255, .28);
}
.btn--primary {
  border-color: transparent;
  background: linear-gradient(90deg, rgba(0, 229, 255, .95), rgba(0, 229, 255, .72));
  color: #03222B;
}
.btn--primary:hover,
.btn--primary:focus-visible {
  background: linear-gradient(90deg, #6BF2FF, var(--c-cyan));
  color: #03222B;
  box-shadow: 0 0 24px rgba(0, 229, 255, .38);
}
.btn--gold {
  border-color: var(--line-gold);
  background: rgba(255, 183, 77, .1);
  color: var(--c-gold);
}
.btn--gold:hover,
.btn--gold:focus-visible { color: var(--c-cream); border-color: var(--c-gold); }
.btn--mini { padding: 7px 13px; font-size: 12px; letter-spacing: .12em; }

/* ------------------------------------------------------------ breadcrumb */
.breadcrumb { padding-top: clamp(16px, 2.4vw, 26px); }
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--txt-mute);
}
.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-right: 8px;
  color: rgba(143, 184, 198, .5);
}
.breadcrumb-link { border-bottom: 1px solid transparent; transition: color var(--t), border-color var(--t); }
.breadcrumb-link:hover { color: var(--c-cyan); border-bottom-color: var(--line-hot); }
.breadcrumb-current { color: var(--c-cream); }

/* --------------------------------------------------- containers & grids */
.wrap {
  width: 100%;
  max-width: var(--w);
  margin: 0 auto;
  padding-inline: var(--gutter);
}
.wrap--narrow { max-width: 900px; }

.section { padding-block: clamp(36px, 5.4vw, 84px); }

.section-head { display: grid; gap: 10px; max-width: 780px; }
.kicker {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .24em;
  color: var(--c-gold);
}
.kicker::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--c-gold);
}
.section-title { font-size: clamp(28px, 3.6vw, 40px); }
.section-note { color: var(--txt-mute); font-size: 16px; max-width: 62ch; }

.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)); }
.grid-rail {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 306px;
  gap: clamp(24px, 3.4vw, 52px);
  align-items: start;
}

/* --------------------------------------------------- cards / plates / tags */
.index-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(18px, 2.2vw, 26px);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(18, 61, 74, .46), rgba(11, 27, 43, .58));
  transition: border-color var(--t), transform var(--t), background var(--t);
}
.index-card::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--c-cyan), rgba(255, 183, 77, .6), transparent);
  opacity: 0;
  transition: opacity var(--t);
}
.index-card:hover,
.index-card:focus-within {
  border-color: var(--line-hot);
  transform: translateY(-2px);
  background: linear-gradient(180deg, rgba(18, 61, 74, .62), rgba(11, 27, 43, .7));
}
.index-card:hover::after,
.index-card:focus-within::after { opacity: 1; }
.index-card-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--c-gold);
}
.index-card-title { font-size: 20px; color: var(--c-cream); }
.index-card-body { font-size: 15.5px; color: var(--txt-mute); line-height: 1.8; }

.plate {
  padding: clamp(16px, 2vw, 24px);
  background: var(--c-cream);
  color: var(--c-brown);
  border: 1px solid rgba(28, 20, 16, .35);
  box-shadow: 8px 8px 0 rgba(0, 229, 255, .14);
}
.plate-label {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: #8A5A1E;
}
.plate-title { font-size: 20px; font-weight: 700; color: var(--c-brown); }
.plate-text { font-size: 15px; line-height: 1.8; color: #3A2C24; }

.tag-list { display: flex; flex-wrap: wrap; gap: 8px; }
.tag-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border: 1px solid var(--line-2);
  background: rgba(18, 61, 74, .32);
  color: var(--txt-mute);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  cursor: pointer;
  transition: color var(--t), border-color var(--t), background var(--t);
}
.tag-pill:hover,
.tag-pill:focus-visible { color: var(--c-soft); border-color: var(--line-hot); }
.tag-pill[data-active],
.tag-pill[aria-pressed="true"] {
  background: var(--c-cyan);
  border-color: var(--c-cyan);
  color: #03222B;
}

/* --------------------------------------------------------- media frames */
.media-frame {
  position: relative;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--line);
  background: rgba(18, 61, 74, .32);
  overflow: hidden;
}
.media-frame img,
.media-frame svg,
.media-frame video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(0, 229, 255, .16), transparent 46%, rgba(11, 27, 43, .6));
  mix-blend-mode: screen;
}
.media-frame__caption {
  position: absolute;
  left: 0; bottom: 0;
  max-width: 100%;
  padding: 8px 12px;
  background: rgba(11, 27, 43, .86);
  border-top: 1px solid var(--line-hot);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--txt-mute);
}
.media-frame__fallback {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .22em;
  color: rgba(143, 184, 198, .62);
  background-image: repeating-linear-gradient(135deg,
    rgba(0, 229, 255, .08) 0 1px, transparent 1px 15px);
}

/* ------------------------------------------------------------------ prose */
.prose {
  max-width: 74ch;
  font-size: 17px;
  line-height: 1.8;
  color: var(--txt);
}
.prose h2 {
  margin: 1.7em 0 .55em;
  font-size: clamp(24px, 2.6vw, 30px);
}
.prose h3 { margin: 1.5em 0 .5em; }
.prose p + p { margin-top: 1em; }
.prose a {
  color: var(--c-cyan);
  border-bottom: 1px solid rgba(0, 229, 255, .42);
  transition: color var(--t), border-color var(--t);
}
.prose a:hover { color: var(--c-soft); border-bottom-color: var(--c-soft); }
.prose ul,
.prose ol { display: grid; gap: .55em; margin: 1em 0; }
.prose ul li { position: relative; padding-left: 1.5em; }
.prose ul li::before {
  content: "";
  position: absolute;
  left: 0; top: .88em;
  width: 9px; height: 1px;
  background: var(--c-gold);
}
.prose ol { counter-reset: prose-ol; }
.prose ol li { position: relative; padding-left: 2.1em; }
.prose ol li::before {
  counter-increment: prose-ol;
  content: counter(prose-ol, decimal-leading-zero);
  position: absolute;
  left: 0; top: .34em;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--c-gold);
}
.prose strong { color: var(--c-cream); }

/* ------------------------------------------------------------- toc / rail */
.toc-nav {
  position: sticky;
  top: calc(var(--hdr) + 18px);
  padding-top: 14px;
  border-top: 1px solid var(--line-2);
}
.toc-title {
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--c-gold);
}
.toc-list { display: grid; gap: 2px; }
.toc-link {
  display: block;
  padding: 8px 10px;
  font-size: 14px;
  color: var(--txt-mute);
  border-left: 2px solid transparent;
  transition: color var(--t), border-color var(--t), background var(--t);
}
.toc-link:hover { color: var(--c-cream); background: rgba(0, 229, 255, .06); }
.toc-link[aria-current="true"] {
  color: var(--c-soft);
  border-left-color: var(--c-cyan);
  background: rgba(0, 229, 255, .09);
}

/* ------------------------------------------------------------ back to top */
.back-to-top {
  position: fixed;
  right: clamp(14px, 2vw, 28px);
  bottom: clamp(14px, 2vw, 28px);
  z-index: 70;
  display: grid;
  place-items: center;
  width: 46px; height: 46px;
  border: 1px solid var(--line-2);
  background: rgba(11, 27, 43, .92);
  color: var(--c-cyan);
  font-family: var(--font-mono);
  font-size: 15px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--t), visibility var(--t), border-color var(--t), color var(--t);
}
.back-to-top[data-show] { opacity: 1; visibility: visible; }
.back-to-top:hover { border-color: var(--line-hot); color: var(--c-soft); }

/* --------------------------------------------------------- responsive */
@media (max-width: 1099px) {
  :root { --hdr: 132px; }

  .header-shell {
    grid-template-columns: auto minmax(0, 1fr) auto;
    grid-template-areas: "brand anchor toggle";
  }

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

  .nav-island {
    position: absolute;
    top: calc(100% + 6px);
    left: var(--gutter);
    right: var(--gutter);
    display: block;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity var(--t), transform var(--t), visibility var(--t);
  }
  .nav-island[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 6px;
    background: rgba(9, 22, 36, .985);
    border-color: var(--line-2);
    box-shadow: 0 28px 70px rgba(0, 0, 0, .62);
  }
  .nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    counter-increment: navidx;
    border-bottom: 1px solid var(--line);
  }
  .nav-item:last-child { border-bottom: 0; }
  .nav-item::before {
    content: counter(navidx, decimal-leading-zero);
    padding-left: 10px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: .18em;
    color: rgba(255, 183, 77, .8);
  }
  .nav-list { counter-reset: navidx; }
  .nav-link {
    flex: 1;
    padding: 15px 16px;
    font-size: 15.5px;
    letter-spacing: .08em;
    border: 0;
    border-left: 2px solid transparent;
  }
  .nav-link[aria-current="page"] { border-left-color: var(--c-gold); }
  .nav-link[aria-current="page"]::after { left: auto; right: 16px; bottom: auto; top: 50%; width: 6px; height: 6px; }

  .anchor-preview { display: none; }

  .footer-shell { grid-template-columns: 1fr; }
  .grid-rail { grid-template-columns: minmax(0, 1fr); }
  .toc-nav { position: static; }
}

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

@media (max-width: 700px) {
  :root { --hdr: 196px; }

  .header-shell {
    grid-template-columns: 1fr auto;
    grid-template-areas:
      "brand toggle"
      "anchor anchor";
    gap: 10px;
    padding: 12px var(--gutter) 14px;
  }
  .brand-island { padding: 8px 14px 8px 10px; }
  .brand-name { font-size: 16px; }
  .brand-mark { width: 34px; height: 34px; font-size: 14px; }

  .anchor-slot {
    justify-content: space-between;
    gap: 12px;
    padding: 8px 8px 8px 14px;
    min-height: 52px;
  }
  .anchor-index,
  .anchor-sub { display: none; }
  .anchor-label { font-size: 14px; }
  .anchor-cta { padding: 9px 14px; font-size: 13px; letter-spacing: .08em; }

  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 22px; }
  .footer-contact { flex-direction: column; gap: 8px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }

  .back-to-top { width: 42px; height: 42px; }
}

@media (max-width: 420px) {
  .brand-sub { display: none; }
  .nav-toggle-text { display: none; }
}

@media (hover: none) {
  body { background-attachment: scroll, scroll, scroll, scroll, scroll; }
}

/* --------------------------------------------------- reduced motion */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    transition-delay: 0ms !important;
  }
  .index-card:hover,
  .index-card:focus-within { transform: none; }
  .anchor-preview { transform: none; }
  .nav-island { transform: none; }
  .scroll-progress-bar { transition: none; }
}

@media print {
  .site-header,
  .site-footer,
  .back-to-top { display: none; }
  body { background: #fff; color: #000; }
}