/* ============================================================
   /assets/site.css — 共享外壳样式（reset / tokens / header / footer / 通用组件）
   ============================================================ */

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

html, body { margin: 0; padding: 0; }

body { overflow-x: hidden; }

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

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

button { font: inherit; color: inherit; background: none; border: 0; }

a { color: inherit; }

main { display: block; }

#main-content { scroll-margin-top: clamp(72px, 10vw, 110px); }

/* ---------- 2. Tokens ---------- */
:root {
  --ink-900: #050A14;
  --ink-800: #0A1424;
  --ink-700: #0D1729;
  --line-blue: #16263C;

  --glass-bg: rgba(168, 196, 224, 0.08);
  --glass-bg-strong: rgba(168, 196, 224, 0.14);
  --glass-line: rgba(168, 196, 224, 0.18);

  --cyan: #2BF0D2;
  --cyan-deep: #0E8F84;
  --amber: #FFB25B;
  --amber-deep: #C97A2B;

  --text: #EAF2FA;
  --text-soft: #8FA3BA;

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

  --radius-lg: 22px;
  --radius-md: 14px;
  --radius-pill: 999px;

  --shadow-float: 0 20px 46px -28px rgba(0, 0, 0, 0.95);
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* ---------- 3. Base type & canvas ---------- */
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--text);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(1000px 560px at 84% -6%, rgba(43, 240, 210, 0.10), transparent 60%),
    radial-gradient(820px 520px at 0% 6%, rgba(255, 178, 91, 0.07), transparent 58%),
    linear-gradient(rgba(22, 38, 60, 0.42) 1px, transparent 1px),
    linear-gradient(90deg, rgba(22, 38, 60, 0.42) 1px, transparent 1px);
  background-size: auto, auto, 88px 88px, 88px 88px;
  background-attachment: fixed;
  background-repeat: no-repeat, no-repeat, repeat, repeat;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.03em;
  line-height: 0.98;
  margin: 0 0 0.5em;
  color: var(--text);
}

h1 { font-size: clamp(2.6rem, 6vw, 5.4rem); }
h2 { font-size: clamp(1.8rem, 3.4vw, 3rem); }
h3 { font-size: 1.375rem; line-height: 1.3; letter-spacing: -0.015em; }

p { margin: 0 0 1em; max-width: 62ch; }

::selection { background: rgba(43, 240, 210, 0.28); color: #FFFFFF; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ---------- 4. Skip link ---------- */
.skip-link {
  position: absolute;
  left: 50%;
  top: -120px;
  transform: translateX(-50%);
  z-index: 300;
  display: inline-block;
  padding: 0.7rem 1.3rem;
  border-radius: 0 0 14px 14px;
  background: var(--cyan);
  color: #04121A;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 0.9375rem;
  text-decoration: none;
  transition: top 0.2s var(--ease);
}

.skip-link:focus { top: 0; }

/* ---------- 5. Layout utilities ---------- */
.container {
  width: 100%;
  max-width: 1240px;
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 40px);
}

.section {
  position: relative;
  padding-block: clamp(56px, 8vw, 110px);
}

.section--tint {
  background: linear-gradient(180deg, rgba(10, 20, 36, 0.92), rgba(10, 20, 36, 0.42));
  box-shadow: inset 0 1px 0 var(--line-blue), inset 0 -1px 0 var(--line-blue);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  margin: 0 0 1rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: currentColor;
  opacity: 0.7;
}

.index-num {
  display: block;
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 3.6vw, 3.25rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: rgba(43, 240, 210, 0.14);
  -webkit-text-stroke: 1px rgba(43, 240, 210, 0.5);
}

.lede {
  font-size: clamp(1.0625rem, 1.4vw, 1.25rem);
  line-height: 1.7;
  color: var(--text-soft);
  max-width: 56ch;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.7rem;
  border: 1px solid rgba(255, 178, 91, 0.35);
  border-radius: var(--radius-pill);
  background: rgba(255, 178, 91, 0.07);
  color: var(--amber);
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  line-height: 1.6;
  white-space: nowrap;
}

/* ---------- 6. Grid ---------- */
.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 32px);
}

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

.span-4 { grid-column: span 4 / span 4; }
.span-5 { grid-column: span 5 / span 5; }
.span-6 { grid-column: span 6 / span 6; }
.span-7 { grid-column: span 7 / span 7; }
.span-8 { grid-column: span 8 / span 8; }
.span-12 { grid-column: span 12 / span 12; }

.col-start-2 { grid-column-start: 2; }
.col-start-3 { grid-column-start: 3; }

/* ---------- 7. Breadcrumbs ---------- */
.breadcrumbs {
  margin: 0 0 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--text-soft);
}

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumbs li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumbs li + li::before {
  content: "/";
  opacity: 0.5;
}

.breadcrumbs a {
  color: var(--text-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.breadcrumbs a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.breadcrumbs [aria-current="page"] { color: var(--text); }

/* ---------- 8. Media containers ---------- */
.media {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  border: 1px solid var(--glass-line);
  background:
    linear-gradient(150deg, rgba(43, 240, 210, 0.18), rgba(10, 20, 36, 0.92) 58%, rgba(255, 178, 91, 0.16));
  isolation: isolate;
}

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

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 52%, rgba(5, 10, 20, 0.62));
  z-index: 1;
}

.media--wide { aspect-ratio: 16 / 9; }
.media--tall { aspect-ratio: 4 / 5; }
.media--square { aspect-ratio: 1 / 1; }

.media-caption {
  margin: 0.6rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--text-soft);
}

/* ---------- 9. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.35rem;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 0.9375rem;
  line-height: 1;
  letter-spacing: 0.01em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease), background 0.18s var(--ease), color 0.18s var(--ease);
}

.btn-primary {
  background: linear-gradient(135deg, var(--cyan) 0%, #8DF9E8 55%, var(--cyan) 100%);
  color: #04121A;
  box-shadow: 0 14px 34px -22px rgba(43, 240, 210, 0.95);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 0 1px rgba(43, 240, 210, 0.5), 0 16px 36px -16px rgba(43, 240, 210, 0.8);
}

.btn-ghost {
  background: var(--glass-bg);
  border-color: var(--glass-line);
  color: var(--text);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.btn-ghost:hover {
  border-color: rgba(43, 240, 210, 0.45);
  color: var(--cyan);
}

/* ---------- 10. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: clamp(10px, 1.4vw, 18px) clamp(12px, 3vw, 28px) 0;
  transition: padding 0.28s var(--ease);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(5, 10, 20, 0.94) 0%, rgba(5, 10, 20, 0.76) 58%, rgba(5, 10, 20, 0) 100%);
}

.site-header[data-scrolled] {
  padding-top: clamp(6px, 0.9vw, 10px);
}

.header-shell {
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.2vw, 14px);
  max-width: 1280px;
  margin-inline: auto;
}

/* brand island */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  flex: none;
  padding: 0.45rem 0.95rem 0.45rem 0.5rem;
  border: 1px solid var(--glass-line);
  border-radius: var(--radius-pill);
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--shadow-float);
  text-decoration: none;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.brand:hover {
  border-color: rgba(43, 240, 210, 0.42);
  background: var(--glass-bg-strong);
}

.brand-mark {
  position: relative;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: none;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 26%, rgba(43, 240, 210, 0.95), rgba(14, 143, 132, 0.38) 60%, rgba(5, 10, 20, 0.92));
  box-shadow: inset 0 0 0 1px rgba(43, 240, 210, 0.35);
}

.brand-mark-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 178, 91, 0.18);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  letter-spacing: -0.02em;
  color: var(--text);
  white-space: nowrap;
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  color: var(--text-soft);
  white-space: nowrap;
}

/* nav island */
.site-nav {
  position: relative;
  display: flex;
  align-items: center;
  padding: 0.35rem;
  border: 1px solid var(--glass-line);
  border-radius: var(--radius-pill);
  background: rgba(13, 23, 41, 0.55);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.nav-item { display: flex; }

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-pill);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-soft);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.18s var(--ease), background 0.18s var(--ease);
}

.nav-link:hover {
  color: var(--text);
  background: rgba(168, 196, 224, 0.10);
}

.nav-link[aria-current="page"] {
  color: #04121A;
  font-weight: 700;
  background: linear-gradient(135deg, var(--cyan) 0%, #8DF9E8 100%);
  box-shadow: 0 8px 24px -14px rgba(43, 240, 210, 0.95);
}

.nav-num {
  display: none;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  opacity: 0.7;
}

.nav-panel-foot { display: none; }

.nav-panel-version {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--text-soft);
}

.nav-panel-cta { font-size: 0.875rem; }

/* action island */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: auto;
}

.version-chip {
  padding: 0.35rem 0.6rem;
  border: 1px solid rgba(255, 178, 91, 0.35);
  border-radius: 8px;
  background: rgba(255, 178, 91, 0.08);
  color: var(--amber);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.header-cta {
  padding: 0.6rem 1.05rem;
  font-size: 0.875rem;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 0.85rem;
  border: 1px solid var(--glass-line);
  border-radius: var(--radius-pill);
  background: var(--glass-bg);
  cursor: pointer;
  transition: border-color 0.18s var(--ease);
}

.nav-toggle:hover { border-color: rgba(43, 240, 210, 0.45); }

.nav-toggle-icon {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 16px;
  height: 14px;
}

.nav-toggle-bar {
  display: block;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transition: transform 0.24s var(--ease);
}

.nav-toggle-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--text-soft);
}

.site-header[data-open] .nav-toggle-bar:first-child {
  transform: translateY(3px) rotate(45deg);
}

.site-header[data-open] .nav-toggle-bar:last-child {
  transform: translateY(-3px) rotate(-45deg);
}

/* scroll progress */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: rgba(22, 38, 60, 0.65);
  overflow: hidden;
  pointer-events: none;
}

.scroll-progress-bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--amber) 100%);
  transition: transform 0.12s linear;
}

/* ---------- 11. Footer ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 7vw, 96px);
  border-top: 1px solid var(--line-blue);
  background: linear-gradient(180deg, rgba(10, 20, 36, 0.36) 0%, rgba(5, 10, 20, 0.96) 42%);
  padding-block: clamp(40px, 6vw, 72px) clamp(24px, 3vw, 36px);
}

.footer-shell {
  max-width: 1240px;
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 40px);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.25fr 1fr;
  gap: clamp(24px, 3vw, 48px);
}

.footer-col { min-width: 0; }

.footer-brand {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.375rem;
  letter-spacing: -0.025em;
  color: var(--text);
}

.footer-note {
  margin: 0 0 1rem;
  max-width: 28ch;
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--text-soft);
}

.footer-note--small {
  margin: 1rem 0 0;
  font-size: 0.8125rem;
  color: rgba(143, 163, 186, 0.85);
}

.footer-icp {
  margin: 0;
  font-size: 0.8125rem;
  color: var(--text-soft);
}

.footer-heading {
  margin: 0 0 1rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0.18em;
  color: var(--amber);
}

.footer-list {
  display: grid;
  gap: 0.55rem;
  font-size: 0.9375rem;
}

.footer-link {
  color: var(--text-soft);
  text-decoration: none;
  transition: color 0.16s var(--ease);
}

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

.footer-contact-item {
  display: grid;
  gap: 0.15rem;
  margin-bottom: 0.85rem;
}

.footer-contact-label {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: rgba(143, 163, 186, 0.8);
}

.footer-contact-value {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.9375rem;
  color: var(--text);
  word-break: break-word;
}

.footer-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
  color: var(--text);
}

.footer-copy {
  padding: 0.15rem 0.55rem;
  border: 1px solid rgba(43, 240, 210, 0.3);
  border-radius: var(--radius-pill);
  background: rgba(43, 240, 210, 0.08);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 0.16s var(--ease), color 0.16s var(--ease);
}

.footer-copy:hover { background: rgba(43, 240, 210, 0.22); }

.footer-copy.is-copied {
  background: var(--cyan);
  color: #04121A;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  margin-top: clamp(28px, 4vw, 48px);
  padding-top: 1.25rem;
  border-top: 1px solid var(--line-blue);
}

.footer-bottom-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  max-width: none;
  font-size: 0.8125rem;
  color: var(--text-soft);
}

.footer-dot {
  opacity: 0.45;
}

/* ---------- 12. Reveal protocol ---------- */
[data-reveal] {
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
  transition-delay: calc(var(--stagger, 0) * 80ms);
}

.has-js [data-reveal] {
  opacity: 0;
  transform: translate3d(0, 12px, 0);
}

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

/* ---------- 13. Responsive ---------- */
@media (max-width: 1180px) and (min-width: 961px) {
  .nav-link {
    padding: 0.45rem 0.6rem;
    font-size: 0.875rem;
  }
  .brand-sub { display: none; }
}

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }
  .header-cta { display: none; }

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    display: block;
    padding: 14px;
    border-radius: var(--radius-lg);
    background: rgba(9, 17, 31, 0.97);
    box-shadow: 0 30px 60px -30px rgba(0, 0, 0, 0.95);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px) scale(0.99);
    transition: opacity 0.22s var(--ease), transform 0.22s var(--ease), visibility 0.22s var(--ease);
  }

  .site-nav .nav-list {
    display: grid;
    gap: 2px;
  }

  .nav-link {
    display: flex;
    padding: 0.75rem 0.8rem;
    border-radius: var(--radius-md);
    font-size: 1rem;
  }

  .nav-num {
    display: inline-block;
    min-width: 1.6rem;
    color: var(--cyan);
  }

  .nav-link[aria-current="page"] .nav-num { color: rgba(4, 18, 26, 0.75); }

  .nav-panel-foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-top: 10px;
    padding-top: 12px;
    border-top: 1px solid var(--line-blue);
  }

  .site-header[data-open] .site-nav {
    opacity: 1;
    visibility: visible;
    transform: none;
  }
}

@media (max-width: 860px) {
  .grid-12 > * { grid-column: 1 / -1; }

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

@media (max-width: 560px) {
  .brand-sub { display: none; }
  .version-chip { display: none; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  h1 { font-size: clamp(2.2rem, 9vw, 3rem); }
}

/* ---------- 14. Motion preference ---------- */
@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;
  }

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

  .skip-link:focus { top: 0; }
}