/* ==========================================================================
   巨星中心 · 共享样式表 /assets/site.css
   深靛蓝控制室 + 霓虹青刻度 + 洋红追光
   ========================================================================== */

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

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

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

ul, ol { padding: 0; }

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

button { font: inherit; color: inherit; }

/* -------- tokens -------- */
:root {
  --indigo-deep: #05070F;
  --indigo: #0B1230;
  --indigo-step: #16204A;
  --cyan: #35E6D2;
  --magenta: #FF2E8B;
  --star: #F4F7FB;
  --rock: #7C8798;
  --moss: #4F7A63;
  --clay: #C97B5A;
  --paper: #EDE6D8;

  --line: rgba(124, 135, 152, 0.28);
  --line-soft: rgba(124, 135, 152, 0.16);
  --line-cyan: rgba(53, 230, 210, 0.5);

  --sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Source Han Sans SC",
          "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", Arial, sans-serif;
  --serif: "Songti SC", "Source Han Serif SC", "Noto Serif CJK SC", "SimSun", Georgia, serif;
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;

  --fs-12: 12px;
  --fs-13: 13px;
  --fs-16: 16px;
  --fs-20: 20px;
  --fs-28: 28px;
  --fs-40: 40px;
  --fs-56: 56px;
  --fs-72: 72px;

  --shell: 1440px;
  --pad: 24px;

  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* -------- base -------- */
body {
  font-family: var(--sans);
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--star);
  background-color: var(--indigo);
  background-image:
    radial-gradient(60% 45% at 8% 0%, rgba(53, 230, 210, 0.10), transparent 62%),
    radial-gradient(55% 40% at 92% 5%, rgba(255, 46, 139, 0.11), transparent 60%),
    radial-gradient(85% 60% at 50% 118%, rgba(22, 32, 74, 0.9), transparent 72%),
    repeating-linear-gradient(0deg, rgba(124, 135, 152, 0.055) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(90deg, rgba(124, 135, 152, 0.055) 0 1px, transparent 1px 64px);
  background-repeat: no-repeat, no-repeat, no-repeat, repeat, repeat;
  background-size: auto, auto, auto, 64px 64px, 64px 64px;
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--cyan); text-decoration: none; }
a:hover { color: var(--star); }

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

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

/* -------- typography -------- */
.display {
  font-weight: 800;
  font-size: clamp(38px, 6vw, var(--fs-72));
  line-height: 1.06;
  letter-spacing: -0.02em;
  margin-bottom: 18px;
}

.h1-page {
  font-weight: 800;
  font-size: clamp(32px, 4.4vw, var(--fs-56));
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.serif-title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(22px, 2.4vw, 30px);
  line-height: 1.32;
  letter-spacing: 0.01em;
}

.lede {
  max-width: 46ch;
  font-size: 18px;
  line-height: 1.7;
  color: rgba(244, 247, 251, 0.78);
}

.mono-label {
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--rock);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 14px;
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--cyan);
}

.prose {
  max-width: 680px;
  font-size: 16.5px;
  line-height: 1.85;
  color: rgba(244, 247, 251, 0.86);
}

.prose p { margin-bottom: 1.15em; }
.prose h2 { font-size: var(--fs-28); line-height: 1.3; letter-spacing: -0.01em; margin: 1.6em 0 0.6em; }
.prose h3 { font-size: var(--fs-20); line-height: 1.4; margin: 1.4em 0 0.5em; }
.prose ul, .prose ol { margin: 0 0 1.15em 1.2em; }
.prose li { margin-bottom: 0.4em; }
.prose a { border-bottom: 1px solid var(--line-cyan); }

.paper-block {
  background: var(--paper);
  color: #23293a;
  padding: clamp(24px, 4vw, 48px);
}

.paper-block .prose { color: #333b4d; }
.paper-block a { color: #0f6d63; border-bottom-color: rgba(15, 109, 99, 0.4); }

/* -------- layout -------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding-left: var(--pad);
  padding-right: var(--pad);
}

.shell--narrow { max-width: 1040px; }

.section { padding: clamp(48px, 7vw, 96px) 0; }
.section--tight { padding: clamp(28px, 4vw, 56px) 0; }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.grid-12 > * { grid-column: span 12; }

.split {
  display: grid;
  grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
  gap: clamp(24px, 4vw, 56px);
}

.split--reverse {
  grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
}

@media (min-width: 901px) {
  .grid-12 > .span-3 { grid-column: span 3; }
  .grid-12 > .span-4 { grid-column: span 4; }
  .grid-12 > .span-5 { grid-column: span 5; }
  .grid-12 > .span-6 { grid-column: span 6; }
  .grid-12 > .span-7 { grid-column: span 7; }
  .grid-12 > .span-8 { grid-column: span 8; }
  .grid-12 > .span-9 { grid-column: span 9; }
  .grid-12 > .span-10 { grid-column: span 10; }
  .grid-12 > .span-12 { grid-column: span 12; }
}

/* -------- buttons -------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 11px 18px;
  font-family: var(--sans);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 0;
  cursor: pointer;
  transition: background-color 0.22s var(--ease), color 0.22s var(--ease),
              border-color 0.22s var(--ease), transform 0.22s var(--ease);
}

.btn--primary {
  background: var(--magenta);
  color: #ffffff;
}

.btn--primary:hover {
  background: #ff52a1;
  color: #ffffff;
  transform: translateY(-1px);
}

.btn--ghost {
  background: transparent;
  border-color: var(--line-cyan);
  color: var(--cyan);
}

.btn--ghost:hover {
  background: rgba(53, 230, 210, 0.1);
  border-color: var(--cyan);
  color: var(--star);
}

.btn--quiet {
  background: rgba(22, 32, 74, 0.6);
  border-color: var(--line);
  color: var(--star);
}

.btn--quiet:hover {
  border-color: var(--line-cyan);
  color: var(--cyan);
}

/* -------- breadcrumb -------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0 0 24px;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.05em;
  color: var(--rock);
}

.breadcrumb li { display: inline-flex; align-items: center; }

.breadcrumb li:not(:last-child)::after {
  content: "/";
  margin-left: 8px;
  color: rgba(124, 135, 152, 0.55);
}

.breadcrumb a { color: var(--rock); }
.breadcrumb a:hover { color: var(--cyan); }
.breadcrumb [aria-current="page"] { color: var(--star); }

/* -------- cards / index -------- */
.card {
  background: rgba(22, 32, 74, 0.55);
  border: 1px solid var(--line);
  padding: 22px 22px 24px;
  transition: border-color 0.24s var(--ease), transform 0.24s var(--ease);
}

.card:hover {
  border-color: var(--line-cyan);
  transform: translateY(-2px);
}

.index-card {
  position: relative;
  padding: 18px 20px 20px 22px;
  background: rgba(22, 32, 74, 0.42);
  border: 1px solid var(--line);
  border-left: 2px solid var(--line-cyan);
  transition: border-color 0.24s var(--ease), transform 0.24s var(--ease);
}

.index-card:hover {
  transform: translateY(-2px);
  border-color: var(--line-cyan);
  border-left-color: var(--cyan);
}

.index-no {
  display: block;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--cyan);
  margin-bottom: 8px;
}

.index-title {
  display: block;
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: -0.01em;
  margin-bottom: 6px;
}

.index-meta {
  display: block;
  font-family: var(--mono);
  font-size: var(--fs-12);
  color: var(--rock);
  letter-spacing: 0.04em;
}

.stagger > *:nth-child(even) { margin-inline-start: 24px; }

.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 9px;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
  border: 1px solid var(--line);
  color: var(--rock);
}

.tag--clay { border-color: rgba(201, 123, 90, 0.6); color: var(--clay); }
.tag--moss { border-color: rgba(79, 122, 99, 0.6); color: #8fc0a6; }

.rule-tick {
  position: relative;
  height: 1px;
  background: var(--line);
  margin: 28px 0;
}

.rule-tick::after {
  content: "";
  position: absolute;
  left: 0;
  top: -3px;
  width: 1px;
  height: 7px;
  background: var(--cyan);
  box-shadow: 120px 0 0 rgba(53, 230, 210, 0.5), 240px 0 0 rgba(53, 230, 210, 0.3);
}

/* -------- frame & media -------- */
.frame {
  position: relative;
  border: 1px solid var(--line);
  padding: 24px;
}

.frame::before,
.frame::after {
  content: "";
  position: absolute;
  width: 12px;
  height: 12px;
}

.frame::before {
  left: -1px; top: -1px;
  border-top: 1px solid var(--cyan);
  border-left: 1px solid var(--cyan);
}

.frame::after {
  right: -1px; bottom: -1px;
  border-bottom: 1px solid var(--cyan);
  border-right: 1px solid var(--cyan);
}

.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: linear-gradient(140deg, var(--indigo-step), var(--indigo-deep) 70%);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--16x9 { aspect-ratio: 16 / 9; }
.media-frame--4x5 { aspect-ratio: 4 / 5; }
.media-frame--21x9 { aspect-ratio: 21 / 9; }
.media-frame--1x1 { aspect-ratio: 1 / 1; }

.media-caption {
  margin-top: 10px;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--rock);
}

/* -------- skip link -------- */
.skip-link {
  position: absolute;
  left: 12px;
  top: -64px;
  z-index: 200;
  padding: 10px 16px;
  background: var(--cyan);
  color: var(--indigo-deep);
  font-size: 14px;
  font-weight: 600;
  transition: top 0.2s var(--ease);
}

.skip-link:focus { top: 12px; }

/* ==========================================================================
   头部
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(11, 18, 48, 0.86);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  backdrop-filter: blur(12px) saturate(140%);
  border-bottom: 1px solid var(--line);
  color: var(--star);
}

.header-shell {
  position: relative;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--pad);
}

.header-main {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 14px 0;
  transition: padding 0.28s var(--ease);
}

.site-header[data-condensed="true"] .header-main { padding: 6px 0; }
.site-header[data-condensed="true"] .brand-sub { display: none; }
.site-header[data-condensed="true"] .utility-bar { padding-top: 3px; padding-bottom: 4px; }

.site-header[data-condensed="true"] .nav-link {
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.09em;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: inherit;
  text-decoration: none;
}

.brand:hover { color: var(--star); }

.brand-glyph {
  position: relative;
  width: 15px;
  height: 15px;
  border: 1px solid var(--cyan);
  background: linear-gradient(135deg, rgba(53, 230, 210, 0.28), transparent 70%);
}

.brand-glyph::after {
  content: "";
  position: absolute;
  inset: 4px;
  background: var(--cyan);
}

.brand:hover .brand-glyph::after {
  background: var(--magenta);
}

.brand-text { display: block; }

.brand-mark {
  display: block;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.brand-sub {
  display: block;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.07em;
  color: var(--rock);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 16px;
  flex: 1 1 auto;
  min-width: 0;
}

.nav-group {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
}

.nav-group--left { justify-content: flex-start; }
.nav-group--right { justify-content: flex-end; }

.nav-divider {
  position: relative;
  flex: 1 1 auto;
  min-width: 24px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line), transparent);
}

.nav-divider i {
  position: absolute;
  left: 50%;
  top: -3px;
  width: 1px;
  height: 7px;
  background: var(--cyan);
  opacity: 0.65;
}

.nav-link {
  position: relative;
  display: inline-block;
  padding: 8px 10px;
  font-size: 14px;
  color: rgba(244, 247, 251, 0.82);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.22s var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 2px;
  height: 1px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.24s var(--ease);
}

.nav-link:hover { color: var(--star); }
.nav-link:hover::after,
.nav-link:focus-visible::after { transform: scaleX(1); }

.nav-link[aria-current="page"] { color: var(--cyan); }
.nav-link[aria-current="page"]::after { transform: scaleX(1); }

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 0;
  color: var(--star);
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: border-color 0.22s var(--ease), color 0.22s var(--ease);
}

.nav-toggle:hover { border-color: var(--line-cyan); color: var(--cyan); }

.nav-toggle-lines {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 16px;
}

.nav-toggle-lines i {
  display: block;
  height: 1px;
  background: currentColor;
  transition: transform 0.24s var(--ease), width 0.24s var(--ease);
}

.nav-toggle-lines i:last-child { width: 70%; }

.nav-toggle[aria-expanded="true"] .nav-toggle-lines i:first-child {
  transform: translateY(2.5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-lines i:last-child {
  width: 100%;
  transform: translateY(-2.5px) rotate(-45deg);
}

.nav-toggle-label { line-height: 1; }

/* -------- 第二栏：帮助入口 -------- */
.utility-bar {
  display: flex;
  align-items: center;
  gap: 18px;
  min-height: 34px;
  padding: 6px 0 8px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.05em;
  color: var(--rock);
}

.utility-link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--cyan);
  white-space: nowrap;
}

.utility-link:hover { color: var(--star); }

.utility-dot {
  width: 6px;
  height: 6px;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(53, 230, 210, 0.18);
  animation: utility-pulse 3.2s ease-in-out infinite;
}

@keyframes utility-pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(53, 230, 210, 0.18); }
  50% { box-shadow: 0 0 0 7px rgba(53, 230, 210, 0); }
}

.utility-quick {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  color: rgba(124, 135, 152, 0.9);
}

.utility-quick-label { white-space: nowrap; }

.utility-quick-links {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 0;
  overflow: hidden;
  transition: max-width 0.32s var(--ease), opacity 0.32s var(--ease);
  opacity: 0;
}

.utility-quick-links a {
  color: rgba(244, 247, 251, 0.72);
  white-space: nowrap;
}

.utility-quick-links a:hover { color: var(--cyan); }

.utility-bar:hover .utility-quick-links,
.utility-quick:focus-within .utility-quick-links {
  max-width: 320px;
  opacity: 1;
}

.utility-meta {
  margin-left: auto;
  color: var(--rock);
  white-space: nowrap;
}

@media (hover: none) {
  .utility-quick-links { max-width: 320px; opacity: 1; }
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 8vw, 96px);
  background: linear-gradient(180deg, rgba(5, 7, 15, 0.5), var(--indigo-deep) 42%);
  border-top: 1px solid var(--line-cyan);
  color: var(--star);
}

.footer-shell {
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(40px, 5vw, 64px) var(--pad) 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 1.1fr 1fr;
  gap: clamp(28px, 4vw, 56px);
}

.footer-mark {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.footer-tagline {
  margin-top: 12px;
  max-width: 30ch;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(244, 247, 251, 0.7);
}

.footer-micro {
  margin-top: 16px;
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
  color: var(--clay);
}

.footer-index-title {
  margin-bottom: 14px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--rock);
}

.footer-nav {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px 18px;
}

.footer-nav a {
  display: inline-block;
  font-size: 14px;
  color: rgba(244, 247, 251, 0.78);
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.footer-nav a:hover {
  color: var(--cyan);
  border-bottom-color: rgba(53, 230, 210, 0.5);
}

.contact-list {
  list-style: none;
  display: grid;
  gap: 14px;
}

.contact-item { display: grid; gap: 3px; }

.contact-key {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--rock);
}

.contact-value {
  font-size: 14px;
  line-height: 1.6;
  color: rgba(244, 247, 251, 0.86);
  word-break: break-word;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 24px;
  margin-top: clamp(32px, 4vw, 48px);
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: var(--fs-12);
  letter-spacing: 0.05em;
  color: var(--rock);
}

.footer-legal { color: var(--rock); }
.footer-note { color: rgba(124, 135, 152, 0.85); }

/* -------- 右下角固定竖列 -------- */
.site-rail {
  position: fixed;
  right: 22px;
  bottom: 24px;
  z-index: 70;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 12px;
}

.rail-top {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  background: rgba(22, 32, 74, 0.92);
  border: 1px solid var(--line);
  border-radius: 0;
  color: var(--star);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  cursor: pointer;
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease),
              border-color 0.22s var(--ease), color 0.22s var(--ease);
}

.rail-top[data-visible] {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.rail-top:hover { border-color: var(--cyan); color: var(--cyan); }

.rail-dot {
  position: relative;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255, 46, 139, 0.6);
  background: radial-gradient(circle at 50% 50%, rgba(255, 46, 139, 0.45), rgba(11, 18, 48, 0.9) 72%);
  animation: rail-breathe 3.2s ease-in-out infinite;
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease);
}

.rail-dot::before {
  content: "";
  width: 8px;
  height: 8px;
  background: var(--magenta);
  box-shadow: 0 0 12px rgba(255, 46, 139, 0.9);
}

.rail-dot:hover { transform: scale(1.06); border-color: var(--magenta); }

@keyframes rail-breathe {
  0%, 100% { box-shadow: 0 0 0 0 rgba(255, 46, 139, 0.34); }
  50% { box-shadow: 0 0 0 9px rgba(255, 46, 139, 0); }
}

.rail-dot-bubble {
  position: absolute;
  right: calc(100% + 10px);
  top: 50%;
  transform: translate(6px, -50%);
  white-space: nowrap;
  padding: 6px 10px;
  background: var(--indigo-step);
  border: 1px solid var(--line);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--star);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.24s var(--ease), transform 0.24s var(--ease);
}

.rail-dot:hover .rail-dot-bubble,
.rail-dot:focus-visible .rail-dot-bubble {
  opacity: 1;
  transform: translate(0, -50%);
}

/* ==========================================================================
   显现动效
   ========================================================================== */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.32s ease-out, transform 0.32s ease-out;
}

.js [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 1180px) {
  .nav-link { padding: 8px 7px; font-size: 13.5px; }
  .header-main { gap: 16px; }
}

@media (max-width: 1000px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    max-height: calc(100vh - 110px);
    overflow-y: auto;
    padding: 8px var(--pad) 20px;
    background: var(--indigo-deep);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line-cyan);
  }

  .site-nav[data-open] { display: flex; }

  .nav-group {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-divider {
    flex: 0 0 auto;
    width: 100%;
    height: 1px;
    margin: 10px 0;
    background: linear-gradient(90deg, var(--line), transparent);
  }

  .nav-divider i { left: 0; top: -3px; }

  .nav-link {
    display: block;
    padding: 13px 2px;
    font-size: 16px;
    border-bottom: 1px solid var(--line-soft);
  }

  .nav-link::after { left: 2px; right: auto; width: 0; }

  .nav-link:hover::after,
  .nav-link:focus-visible::after,
  .nav-link[aria-current="page"]::after {
    width: 26px;
    transform: none;
  }

  .split,
  .split--reverse { grid-template-columns: minmax(0, 1fr); }

  .footer-grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .footer-brand { grid-column: span 2; }
}

@media (max-width: 760px) {
  :root { --pad: 18px; }

  .utility-quick,
  .utility-meta { display: none; }

  .stagger > *:nth-child(even) { margin-inline-start: 0; }

  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-brand { grid-column: span 1; }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .site-rail { right: 14px; bottom: 16px; }
  .rail-dot { width: 40px; height: 40px; }
  .rail-dot-bubble { display: none; }
}

@media (max-width: 640px) {
  .header-actions .btn--primary { display: none; }
  .footer-nav { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 720px) {
  body { background-attachment: scroll; }
}

/* ==========================================================================
   动效降级
   ========================================================================== */
@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;
  }

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

  .rail-dot:hover { transform: none; }
}