/* ==========================================================================
   BOB 中文专区 — /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   ========================================================================== */

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; font-size: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, h6, p, figure, blockquote, ul, ol, dl, dd { margin: 0; }
ul, ol { padding: 0; }
ul[class], ol[class] { list-style: none; }
img, svg, video { display: block; max-width: 100%; }
img { height: auto; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; padding: 0; cursor: pointer; }
address { font-style: normal; }
table { border-collapse: collapse; width: 100%; }

/* ---------- tokens ---------- */
:root {
  --navy-900: #04101F;
  --navy-800: #071828;
  --navy-700: #0B2138;
  --navy-600: #102C48;
  --orange-500: #FF5A1F;
  --orange-300: #FF8A5C;
  --green-400: #3DF28C;
  --amber: #FFC24B;
  --ink: #EAF2F8;
  --muted: #93A7B8;
  --line: #1E3A52;
  --paper: #F5F8FA;
  --paper-ink: #0B2138;

  --font-display: "Archivo Black", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-serif: "Noto Serif SC", "Songti SC", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --fs-12: 0.75rem;
  --fs-14: 0.875rem;
  --fs-17: 1.0625rem;
  --fs-22: 1.375rem;
  --fs-34: 2.125rem;
  --fs-56: 3.5rem;
  --fs-84: 5.25rem;

  --container: 1240px;
  --gutter: 1.25rem;
  --rail: 320px;
  --slant: -6deg;
  --ease: cubic-bezier(.2, .6, .25, 1);
}

@media (min-width: 768px) {
  :root { --gutter: 2rem; }
}

/* ---------- base ---------- */
body {
  min-height: 100vh;
  background-color: var(--navy-900);
  background-image:
    radial-gradient(1200px 620px at 84% -10%, rgba(255, 90, 31, .10), transparent 62%),
    radial-gradient(880px 520px at -8% 14%, rgba(61, 242, 140, .055), transparent 60%);
  background-repeat: no-repeat;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
@media (min-width: 768px) {
  body { font-size: 17px; }
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-wrap: balance;
}
h1 { font-size: clamp(2.5rem, 7vw, 5.25rem); }
h2 { font-size: clamp(1.75rem, 3.6vw, 3.5rem); }
h3 { font-size: clamp(1.25rem, 2vw, 2.125rem); }
h4 { font-size: var(--fs-22); letter-spacing: -0.01em; }

p { color: inherit; }
strong { font-weight: 700; }
::selection { background: var(--orange-500); color: #1a0a00; }

:focus-visible {
  outline: 2px solid var(--green-400);
  outline-offset: 2px;
  border-radius: 1px;
}

/* ---------- skip link ---------- */
.skip-link {
  position: fixed;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 200;
  padding: 0.7rem 1.15rem;
  background: var(--green-400);
  color: var(--paper-ink);
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: 700;
  letter-spacing: 0.06em;
  transform: translateY(-180%);
  transition: transform .15s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- layout ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(2.5rem, 6vw, 5rem); }
.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .6rem 1.5rem;
  margin-bottom: clamp(1.5rem, 3vw, 2.5rem);
}

.rule {
  height: 1px;
  border: 0;
  background: var(--line);
  margin-block: clamp(2rem, 5vw, 4rem);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 1.5rem;
}
@media (max-width: 1024px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .grid-12 { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.25rem; }
}

.with-rail {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--rail);
  gap: clamp(2rem, 4vw, 3.5rem);
  align-items: start;
}
@media (max-width: 1080px) {
  .with-rail { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- typography helpers ---------- */
.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--orange-300);
  line-height: 1.4;
}
.eyebrow--muted { color: var(--muted); }

.data-num {
  font-family: var(--font-mono);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.prose {
  max-width: 68ch;
  font-size: var(--fs-17);
  line-height: 1.78;
  color: var(--ink);
}
.prose > * + * { margin-top: 1.15em; }
.prose h2 { margin-top: 2.4em; font-size: clamp(1.5rem, 2.6vw, 2.125rem); }
.prose h3 { margin-top: 2em; font-family: var(--font-serif); font-weight: 700; font-size: var(--fs-22); letter-spacing: 0; }
.prose p + p { padding-top: 1.15em; border-top: 1px solid var(--line); }
.prose ul, .prose ol { padding-left: 1.35em; list-style: disc; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: .4em; }
.prose a {
  color: var(--orange-300);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.prose a:hover { color: var(--green-400); }
.prose blockquote {
  border-left: 2px solid var(--orange-500);
  padding: .35em 0 .35em 1.25em;
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--ink);
}

.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;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .72rem 1.35rem;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--fs-14);
  font-weight: 500;
  letter-spacing: .06em;
  line-height: 1.4;
  transition: border-color .12s var(--ease), color .12s var(--ease), background-color .12s var(--ease);
}
.btn:hover { border-color: var(--orange-500); color: var(--orange-300); }

.btn--primary {
  background: var(--orange-500);
  border-color: var(--orange-500);
  color: #1a0a00;
  font-weight: 700;
}
.btn--primary:hover {
  background: var(--orange-300);
  border-color: var(--orange-300);
  color: #1a0a00;
}

.btn--ghost { border-color: var(--line); color: var(--muted); }
.btn--ghost:hover { color: var(--ink); border-color: var(--orange-500); }

/* ---------- tags ---------- */
.tag {
  display: inline-block;
  padding: .16rem .5rem;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: .08em;
  line-height: 1.5;
  color: var(--muted);
  white-space: nowrap;
}
.tag--live { color: var(--green-400); border-color: rgba(61, 242, 140, .38); }
.tag--doubt { color: var(--amber); border-color: rgba(255, 194, 75, .38); }
.tag--out { color: var(--orange-300); border-color: rgba(255, 138, 92, .38); }

/* ---------- breadcrumb ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  padding-block: 1.5rem;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--muted);
}
.breadcrumb a { color: var(--muted); border-bottom: 1px solid transparent; transition: color .12s var(--ease), border-color .12s var(--ease); }
.breadcrumb a:hover { color: var(--orange-300); border-bottom-color: var(--orange-500); }
.breadcrumb__sep { color: var(--line); }

/* ---------- panel ---------- */
.panel {
  background: var(--navy-700);
  border: 1px solid var(--line);
  padding: clamp(1.15rem, 2.2vw, 1.6rem);
  box-shadow: 0 1px 0 rgba(0, 0, 0, .45);
}
.panel--sticky { position: sticky; top: 1.5rem; }
@media (max-width: 1080px) {
  .panel--sticky { position: static; }
}

/* ---------- media frame ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  background-color: var(--navy-800);
  background-image: linear-gradient(135deg, var(--navy-700) 0%, var(--navy-900) 62%);
}
.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.92) contrast(1.06);
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(4, 16, 31, 0) 38%, rgba(4, 16, 31, .80) 100%);
}
.media-frame__caption {
  position: absolute;
  left: 1rem;
  right: 1rem;
  bottom: .85rem;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--ink);
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--portrait { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

/* ==========================================================================
   HEADER
   ========================================================================== */
.site-header {
  position: relative;
  z-index: 30;
  background: var(--navy-700);
  border-bottom: 1px solid var(--line);
}
.site-header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 38%;
  height: 2px;
  background: linear-gradient(90deg, var(--orange-500), rgba(255, 90, 31, 0));
}

.site-header__bar {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1.5rem;
  padding-block: clamp(1.6rem, 3vw, 2.5rem) clamp(1.2rem, 2vw, 1.8rem);
}

.masthead-rule {
  display: block;
  width: 100%;
  max-width: 220px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line) 55%, var(--orange-500));
}

.masthead { text-align: center; }
.masthead__brand {
  display: inline-block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.85rem, 4.6vw, 3.25rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink);
  transform: skewX(-2deg);
  transition: color .12s var(--ease);
}
.masthead__brand:hover { color: var(--orange-300); }
.masthead__tagline {
  margin-top: .7rem;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: var(--fs-14);
  letter-spacing: .05em;
  color: var(--muted);
}

.live-status {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  max-width: 270px;
  padding: .5rem .8rem;
  border: 1px solid var(--line);
  background: rgba(61, 242, 140, .045);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  line-height: 1.45;
  letter-spacing: .02em;
  color: var(--muted);
  text-align: left;
}
.live-status__dot {
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green-400);
  box-shadow: 0 0 0 0 rgba(61, 242, 140, .55);
  animation: live-pulse 2.6s ease-out infinite;
}
@keyframes live-pulse {
  0% { box-shadow: 0 0 0 0 rgba(61, 242, 140, .5); }
  70%, 100% { box-shadow: 0 0 0 9px rgba(61, 242, 140, 0); }
}

/* ---------- nav strip ---------- */
.site-nav-wrap {
  background: var(--navy-800);
  border-top: 1px solid var(--line);
}
.site-nav-wrap__inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1rem;
  padding-block: .55rem;
  min-height: 54px;
}

.site-nav { grid-column: 2; }

.site-nav__list {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(.35rem, 1.7vw, 1.8rem);
  list-style: none;
  margin: 0;
  padding: 0;
}
.site-nav__link {
  display: inline-block;
  padding: .45rem .15rem;
  border-bottom: 2px solid transparent;
  font-size: var(--fs-14);
  font-weight: 500;
  letter-spacing: .06em;
  color: var(--muted);
  transition: color .12s var(--ease), border-color .12s var(--ease);
}
.site-nav__link:hover {
  color: var(--orange-300);
  border-bottom-color: var(--orange-500);
}
.site-nav__link[aria-current="page"] {
  color: var(--ink);
  border-bottom-color: var(--orange-500);
}

.site-nav-wrap__meta {
  grid-column: 3;
  justify-self: end;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .12em;
  color: var(--navy-600);
  white-space: nowrap;
  filter: brightness(2.1);
  opacity: .72;
}

/* ---------- nav toggle ---------- */
.nav-toggle {
  grid-column: 1;
  display: none;
  align-items: center;
  gap: .55rem;
  padding: .5rem .8rem;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink);
  transition: border-color .12s var(--ease), color .12s var(--ease);
}
.nav-toggle:hover { border-color: var(--orange-500); color: var(--orange-300); }
.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  width: 14px;
}
.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  background: currentColor;
  transition: transform .18s var(--ease), opacity .18s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(4.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-4.5px) rotate(-45deg); }

/* ---------- scroll progress ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 90;
  pointer-events: none;
}
.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--orange-500), var(--green-400));
  transition: transform .08s linear;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: clamp(4rem, 10vw, 7rem);
  background: var(--navy-700);
  border-top: 1px solid var(--line);
}
.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(420px, 42%);
  height: 2px;
  background: linear-gradient(90deg, var(--orange-500), rgba(255, 90, 31, 0));
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr) minmax(0, 1.15fr);
  gap: clamp(2rem, 4vw, 3.5rem);
  padding-block: clamp(2.5rem, 5vw, 4rem) clamp(1.8rem, 3vw, 2.5rem);
}
@media (max-width: 900px) {
  .footer-inner { grid-template-columns: minmax(0, 1fr); gap: 2rem; }
}

.footer-brand__line {
  margin-top: .85rem;
  max-width: 24ch;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: var(--fs-22);
  line-height: 1.45;
  color: var(--ink);
}

.footer-nav__list {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem 1.35rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer-nav__link {
  display: inline-block;
  padding-block: .1rem;
  border-bottom: 1px solid transparent;
  font-size: var(--fs-14);
  color: var(--muted);
  transition: color .12s var(--ease), border-color .12s var(--ease);
}
.footer-nav__link:hover { color: var(--orange-300); border-bottom-color: var(--orange-500); }

.footer-meta {
  display: flex;
  flex-direction: column;
  gap: .7rem;
  font-size: var(--fs-14);
  line-height: 1.6;
  color: var(--muted);
}
.footer-meta__service {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .02em;
  color: var(--ink);
}
.footer-meta__addr { color: var(--muted); }
.footer-meta__icp {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--muted);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: .5rem 1.5rem;
  padding-block: 1.35rem;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--muted);
}
.footer-base__copy { color: var(--muted); }
.footer-base__note { max-width: 56ch; color: var(--navy-600); filter: brightness(2.2); opacity: .8; }

/* ==========================================================================
   RESPONSIVE / MOTION
   ========================================================================== */
@media (max-width: 900px) {
  .site-header__bar {
    grid-template-columns: minmax(0, 1fr);
    justify-items: center;
    gap: 1.1rem;
    padding-block: 1.6rem 1.35rem;
  }
  .masthead-rule { display: none; }
  .live-status {
    justify-self: center;
    max-width: 100%;
    text-align: left;
  }

  .site-nav-wrap__inner {
    grid-template-columns: auto minmax(0, 1fr);
    gap: .6rem;
    padding-block: .6rem;
  }
  .nav-toggle { display: inline-flex; }
  .site-nav-wrap__meta { display: none; }

  .site-nav {
    grid-column: 1 / -1;
    grid-row: 2;
    display: none;
    margin-top: .6rem;
    border-top: 1px solid var(--line);
  }
  .site-nav[data-open] { display: block; }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .site-nav__link {
    display: block;
    padding: .9rem .25rem;
    border-bottom: 1px solid var(--line);
    border-left: 2px solid transparent;
    font-size: var(--fs-17);
    color: var(--ink);
  }
  .site-nav__link:hover,
  .site-nav__link[aria-current="page"] {
    color: var(--orange-300);
    border-bottom-color: var(--line);
    border-left-color: var(--orange-500);
  }
}

@media (max-width: 480px) {
  .masthead__tagline { font-size: var(--fs-12); }
  .footer-base { justify-content: flex-start; }
}

@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;
  }
  .scroll-progress__bar { transition: none; }
}