:root {
  --ink: #10233F;
  --ink-deep: #0A1729;
  --ink-soft: #1D3A5F;
  --orange: #F0803C;
  --orange-soft: #FBE3D2;
  --mist: #E7E9EC;
  --paper: #FAF8F5;
  --mint: #7FC8A9;
  --text: #2B3440;
  --text-muted: #5C6672;
  --glass: rgba(250, 248, 245, 0.62);
  --ink-text: #F2F4F7;
  --line: rgba(16, 35, 63, 0.12);
  --line-ink: rgba(242, 244, 247, 0.16);
  --font-display: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", "Courier New", monospace;
  --wrap: 1220px;
  --gutter: 20px;
  --radius: 16px;
  --shadow: 0 18px 40px -26px rgba(10, 23, 41, 0.45);
}

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.2;
  color: var(--ink);
  margin: 0 0 0.6em;
  letter-spacing: 0;
}

h1 { font-size: clamp(34px, 5vw, 56px); }
h2 { font-size: clamp(26px, 3.4vw, 32px); }
h3 { font-size: 26px; }
h4 { font-size: 20px; }
h5, h6 { font-size: 17px; font-weight: 700; }

p { margin: 0 0 1em; }

a { color: var(--ink); text-decoration: none; }
a:hover { color: var(--orange); }

ul, ol { margin: 0 0 1em; padding-left: 1.2em; }
li { margin: 0.25em 0; }

img { max-width: 100%; height: auto; display: block; }

button { font: inherit; color: inherit; }

:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 3px;
  border-radius: 4px;
}

.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  font-variant-numeric: tabular-nums;
}

.container {
  width: min(100% - (var(--gutter) * 2), var(--wrap));
  margin-inline: auto;
}

.container--narrow { width: min(100% - (var(--gutter) * 2), 780px); }

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--orange);
  margin: 0 0 12px;
}

.lede {
  max-width: 38em;
  font-size: 20px;
  line-height: 1.8;
  color: var(--text-muted);
}

.section { padding: 64px 0; }
.section--tight { padding: 40px 0; }
.section--mist { background: var(--mist); }
.section--ink { background: var(--ink); color: var(--ink-text); }
.section--ink h1, .section--ink h2, .section--ink h3, .section--ink h4 { color: var(--ink-text); }
.section--ink a { color: var(--ink-text); }
.section--ink .lede { color: rgba(242, 244, 247, 0.78); }

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute;
  left: 12px;
  top: -60px;
  z-index: 200;
  padding: 10px 16px;
  border-radius: 0 0 10px 10px;
  background: var(--orange);
  color: #FFFFFF;
  font-weight: 700;
  transition: top 0.2s ease;
}
.skip-link:focus { top: 0; color: #FFFFFF; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background: var(--ink);
  color: var(--ink-text);
  border-bottom: 1px solid rgba(242, 244, 247, 0.1);
}

.brand-strip { border-bottom: 1px solid var(--line-ink); }

.brand-strip__inner,
.nav-bar__inner {
  width: min(100% - (var(--gutter) * 2), var(--wrap));
  margin-inline: auto;
}

.brand-strip__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
  transition: padding 0.35s ease;
}

.site-header--condensed .brand-strip__inner { padding: 5px 0; }

.brand-mark {
  display: flex;
  align-items: baseline;
  gap: 14px;
  color: var(--ink-text);
  min-width: 0;
}
.brand-mark:hover { color: var(--ink-text); }

.brand-mark__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 24px;
  letter-spacing: 0.06em;
  color: #FFFFFF;
}

.brand-mark__line {
  font-size: 14px;
  color: rgba(242, 244, 247, 0.7);
  border-left: 1px solid var(--line-ink);
  padding-left: 14px;
  transition: opacity 0.3s ease;
}

.site-header--condensed .brand-mark__line { opacity: 0; }

.brand-strip__links {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

.quick-link {
  display: inline-block;
  padding: 6px 14px;
  border: 1px solid var(--line-ink);
  border-radius: 999px;
  font-size: 14px;
  color: rgba(242, 244, 247, 0.86);
  transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}
.quick-link:hover {
  background: rgba(240, 128, 60, 0.16);
  border-color: rgba(240, 128, 60, 0.5);
  color: #FFFFFF;
}

.nav-bar { background: rgba(10, 23, 41, 0.92); }

.nav-bar__inner {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 8px 0;
  min-height: 58px;
}

.nav-bar__label {
  margin: 0;
  font-size: 12px;
  color: rgba(242, 244, 247, 0.42);
  white-space: nowrap;
}

.nav-panel { flex: 1 1 auto; min-width: 0; }

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-list__item { margin: 0; }

.nav-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 14px;
  border-radius: 10px;
  font-size: 15px;
  color: rgba(242, 244, 247, 0.78);
  transition: background 0.2s ease, color 0.2s ease;
}
.nav-link:hover {
  background: rgba(242, 244, 247, 0.08);
  color: #FFFFFF;
}

.nav-link__index {
  font-size: 12px;
  color: rgba(242, 244, 247, 0.42);
  transition: color 0.2s ease;
}

.nav-link[aria-current="page"] {
  background: rgba(240, 128, 60, 0.16);
  color: #FFFFFF;
  box-shadow: inset 0 0 0 1px rgba(240, 128, 60, 0.34);
}
.nav-link[aria-current="page"] .nav-link__index { color: var(--orange); }

.mobile-index { display: none; }

.mobile-index__link {
  flex: 1 1 0;
  text-align: center;
  padding: 11px 10px;
  border-radius: 10px;
  border: 1px solid var(--line-ink);
  font-size: 14px;
  color: var(--ink-text);
  background: rgba(242, 244, 247, 0.06);
}
.mobile-index__link:hover { color: #FFFFFF; background: rgba(242, 244, 247, 0.12); }

.mobile-index__link--accent {
  background: var(--orange);
  border-color: var(--orange);
  color: #FFFFFF;
  font-weight: 700;
}
.mobile-index__link--accent:hover { background: #DA6C2C; color: #FFFFFF; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border: 1px solid var(--line-ink);
  border-radius: 10px;
  background: transparent;
  color: var(--ink-text);
  cursor: pointer;
  font-size: 14px;
  margin-left: auto;
}
.nav-toggle:hover { border-color: rgba(240, 128, 60, 0.55); }

.nav-toggle__bars {
  position: relative;
  width: 18px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  display: inline-block;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform 0.25s ease;
}
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }

.site-header[data-open] .nav-toggle__bars { background: transparent; }
.site-header[data-open] .nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { transform: translateY(-6px) rotate(-45deg); }
.site-header[data-open] .nav-toggle { border-color: rgba(240, 128, 60, 0.6); color: #FFFFFF; }

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  display: block;
  background: var(--orange);
  transform: scaleX(var(--progress, 0));
  transform-origin: 0 50%;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 700;
  font-size: 16px;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.btn--primary { background: var(--orange); color: #FFFFFF; }
.btn--primary:hover { background: #DA6C2C; color: #FFFFFF; transform: translateY(-2px); }
.btn--ghost { border-color: var(--line); color: var(--ink); background: transparent; }
.btn--ghost:hover { border-color: var(--orange); color: var(--orange); }

/* ---------- Breadcrumb ---------- */
.breadcrumb { background: var(--mist); padding: 14px 0; border-bottom: 1px solid var(--line); }
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 14px;
  color: var(--text-muted);
}
.breadcrumb__item { display: inline-flex; align-items: center; gap: 8px; margin: 0; }
.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: rgba(92, 102, 114, 0.5);
  font-family: var(--font-mono);
}
.breadcrumb__link { color: var(--text-muted); }
.breadcrumb__link:hover { color: var(--orange); }
.breadcrumb__current { color: var(--ink); font-weight: 700; }

/* ---------- Shared content components ---------- */
.glass-panel {
  background: var(--glass);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  backdrop-filter: blur(14px) saturate(140%);
  border: 1px solid rgba(16, 35, 63, 0.12);
  border-radius: 18px;
  padding: 22px;
  color: var(--text);
}

.card {
  position: relative;
  background: #FFFFFF;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: transform 0.25s ease, border-color 0.25s ease;
}
.card:hover { transform: translateY(-3px); border-color: rgba(240, 128, 60, 0.4); }

.card__index {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--orange);
  margin-bottom: 10px;
}

.grid { display: grid; gap: 24px; }
.grid--split { grid-template-columns: 4fr 7fr; }
.grid--index { grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); align-items: start; }
.grid--index > *:nth-child(3n + 2) { margin-top: 22px; }

.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: var(--radius);
  background: linear-gradient(140deg, var(--ink) 0%, var(--ink-soft) 100%);
  aspect-ratio: 4 / 3;
  width: 100%;
}
.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame__img { width: 100%; height: 100%; object-fit: cover; display: block; }
.media-frame__caption {
  position: absolute;
  left: 14px;
  bottom: 14px;
  margin: 0;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(10, 23, 41, 0.68);
  color: var(--ink-text);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}

/* ---------- Reveal ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.js .reveal.is-visible { opacity: 1; transform: none; }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--ink-deep);
  color: var(--ink-text);
  margin-top: 0;
}

.footer-shell {
  display: grid;
  grid-template-columns: minmax(230px, 1fr) 2.4fr;
  gap: 48px;
  padding: 56px 0 40px;
}

.footer-brand__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 30px;
  letter-spacing: 0.08em;
  color: #FFFFFF;
  margin: 0 0 6px;
}

.footer-brand__line {
  font-size: 16px;
  color: var(--ink-text);
  margin: 0 0 12px;
}

.footer-brand__note {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(242, 244, 247, 0.62);
  margin: 0 0 16px;
  max-width: 26em;
}

.footer-brand__coord {
  font-size: 12px;
  color: rgba(240, 128, 60, 0.9);
  margin: 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  align-content: start;
}

.footer-col__title {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #FFFFFF;
  margin: 0 0 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-ink);
}

.footer-list { list-style: none; margin: 0; padding: 0; }
.footer-list li { margin: 0 0 8px; }

.footer-link {
  font-size: 15px;
  color: rgba(242, 244, 247, 0.72);
  transition: color 0.2s ease;
}
.footer-link:hover { color: var(--orange); }

.footer-meta { border-top: 1px solid var(--line-ink); padding: 20px 0 28px; }

.footer-meta__inner { display: grid; gap: 6px; }

.footer-contact {
  margin: 0;
  font-size: 14px;
  color: rgba(242, 244, 247, 0.78);
}

.footer-copy {
  margin-left: 8px;
  padding: 3px 12px;
  border-radius: 999px;
  border: 1px solid var(--line-ink);
  background: transparent;
  color: rgba(242, 244, 247, 0.78);
  font-size: 13px;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.footer-copy:hover { border-color: rgba(240, 128, 60, 0.6); color: #FFFFFF; }
.footer-copy.is-copied { background: rgba(127, 200, 169, 0.22); border-color: var(--mint); color: #FFFFFF; }

.footer-address {
  margin: 0;
  font-size: 14px;
  color: rgba(242, 244, 247, 0.6);
}

.footer-legal {
  margin: 6px 0 0;
  font-size: 13px;
  color: rgba(242, 244, 247, 0.5);
}

/* ---------- Responsive ---------- */
@media (max-width: 1180px) {
  .grid--split { grid-template-columns: 1fr; }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }

  .nav-bar__label { display: none; }

  .nav-panel {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    max-height: calc(100vh - 100px);
    overflow-y: auto;
    padding: 14px 20px 22px;
    background: var(--ink);
    border-top: 1px solid var(--line-ink);
    box-shadow: 0 24px 40px -20px rgba(10, 23, 41, 0.6);
  }

  .site-header[data-open] .nav-panel { display: block; }

  .mobile-index {
    display: flex;
    gap: 10px;
    padding-bottom: 12px;
    margin-bottom: 12px;
    border-bottom: 1px dashed var(--line-ink);
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }

  .nav-link {
    display: flex;
    justify-content: flex-start;
    padding: 13px 12px;
    font-size: 16px;
    border-radius: 10px;
  }

  .footer-shell { grid-template-columns: 1fr; gap: 32px; padding: 44px 0 32px; }

  .grid--index > *:nth-child(3n + 2) { margin-top: 0; }

  .section { padding: 48px 0; }
}

@media (max-width: 640px) {
  :root { --gutter: 16px; }

  body { font-size: 16px; line-height: 1.8; }

  .brand-mark { flex-direction: column; align-items: flex-start; gap: 2px; }

  .brand-mark__line {
    opacity: 1;
    border-left: 0;
    padding-left: 0;
    font-size: 12px;
  }

  .site-header--condensed .brand-mark__line { opacity: 0.55; }

  .quick-link { padding: 5px 11px; font-size: 13px; }

  .footer-grid { grid-template-columns: 1fr 1fr; gap: 24px; }

  .footer-contact { line-height: 1.7; }

  .footer-copy { display: block; margin: 8px 0 0; }

  .grid { gap: 18px; }
}

@media (max-width: 390px) {
  .footer-grid { grid-template-columns: 1fr; }
  .brand-strip__links { gap: 6px; }
}

@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 .reveal { opacity: 1; transform: none; }
  .card:hover { transform: none; }
  .btn--primary:hover { transform: none; }
}