*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --base-dark: #0B1220;
  --panel-dark: #111A2B;
  --panel-light: #F4F6F9;
  --text-primary: #E2E8F0;
  --text-secondary: #94A3B8;
  --accent-cyan: #00E5A0;
  --accent-blue: #00A8FF;
  --accent-purple: #8B5CF6;
  --accent-orange: #FF7849;
  --border-line: #1E293B;
  --success-green: #22C55E;
  --font-sans: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", "SFMono-Regular", Consolas, monospace;
  --ease: .18s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--base-dark);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color var(--ease), border-color var(--ease), background-color var(--ease), box-shadow var(--ease), transform var(--ease);
}

a:hover { color: var(--accent-cyan); }

img, svg, video { display: block; max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: none; cursor: pointer; }
ul, ol { list-style: none; }
address { font-style: normal; }
main, article, aside, section, header, footer, nav, figure, figcaption { display: block; }

:focus-visible { outline: 2px solid var(--accent-cyan); outline-offset: 3px; border-radius: 2px; }
#main-content { min-height: 70vh; }
#main-content:focus { outline: none; }

.container { width: min(var(--content-w, 1180px), 92vw); margin-inline: auto; }
.mono { font-family: var(--font-mono); letter-spacing: .08em; }
.mono-strong { font-family: var(--font-mono); font-weight: 700; color: var(--accent-orange); letter-spacing: .06em; }
.text-secondary { color: var(--text-secondary); }
.text-cyan { color: var(--accent-cyan); }
.text-blue { color: var(--accent-blue); }
.content-block { max-width: 78ch; }
.content-narrow { max-width: 62ch; }

.skip-link {
  position: fixed;
  top: -90px;
  left: 16px;
  z-index: 1200;
  display: inline-flex;
  align-items: center;
  padding: 10px 18px;
  background: var(--accent-cyan);
  color: #04121A;
  font-weight: 800;
  font-size: 14px;
  line-height: 1;
  box-shadow: 0 0 0 4px rgba(0, 229, 160, .18);
  transition: top .2s ease;
}

.skip-link:focus { top: 16px; }

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1100;
  width: 100%;
  height: 3px;
  background: transparent;
  pointer-events: none;
}

.scroll-progress-bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue), var(--accent-purple));
}

.site-header { position: relative; z-index: 100; background: var(--base-dark); }

.masthead-meta { background: #080E1A; border-bottom: 1px solid var(--border-line); }
.masthead-meta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 34px;
  padding-block: 5px;
}

.masthead-index {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.masthead-index::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--accent-cyan);
  box-shadow: 0 0 8px var(--accent-cyan);
}

.masthead-date { color: var(--text-secondary); font-size: 11px; letter-spacing: .1em; }

.masthead-main {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding-block: 34px 28px;
}

.brand {
  grid-column: 2;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  line-height: 1.05;
}

.brand-name {
  font-size: 36px;
  font-weight: 800;
  letter-spacing: .02em;
  color: var(--text-primary);
  font-family: var(--font-sans);
}

.brand-accent { color: var(--accent-cyan); }

.brand-sub {
  margin-top: 8px;
  font-size: 11px;
  letter-spacing: .3em;
  color: var(--text-secondary);
  text-transform: uppercase;
  transition: color var(--ease);
}

.brand:hover .brand-sub { color: var(--accent-cyan); }

.masthead-actions {
  grid-column: 3;
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 18px;
}

.status-lamp {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 11px;
}

.status-lamp-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success-green);
  box-shadow: 0 0 8px rgba(34, 197, 94, .8);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border: 1px solid var(--border-line);
  background: transparent;
  color: var(--text-primary);
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: .06em;
  line-height: 1;
}

.btn-primary {
  border-color: var(--accent-cyan);
  background: var(--accent-cyan);
  color: #04121A;
  box-shadow: 0 0 0 1px rgba(0, 229, 160, .25);
}

.btn-primary:hover {
  background: var(--accent-blue);
  border-color: var(--accent-blue);
  color: #04121A;
  box-shadow: 0 0 18px rgba(0, 168, 255, .35);
}

.btn-ghost { border-color: var(--accent-blue); color: var(--accent-blue); }
.btn-ghost:hover { background: var(--accent-blue); color: #04121A; }
.btn-sm { padding: 9px 16px; font-size: 12px; }

.masthead-nav-wrap {
  position: relative;
  border-top: 1px solid var(--border-line);
  border-bottom: 1px solid var(--border-line);
  background: var(--panel-dark);
}

.masthead-nav-wrap::before {
  content: "";
  position: absolute;
  top: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-cyan) 0%, var(--accent-blue) 60%, var(--accent-purple) 100%);
}

.masthead-nav-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  min-height: 58px;
}

.nav-brand-inline {
  display: none;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--text-secondary);
}

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

.nav-list { display: flex; align-items: center; justify-content: center; gap: 2px; }

.nav-list a {
  position: relative;
  display: inline-block;
  padding: 18px 14px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--text-secondary);
  border-bottom: 2px solid transparent;
}

.nav-list a::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: -2px;
  height: 2px;
  background: var(--accent-cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .24s ease;
}

.nav-list a:hover { color: var(--text-primary); }
.nav-list a:hover::after { transform: scaleX(1); }
.nav-list a[aria-current="page"] { color: var(--accent-cyan); }
.nav-list a[aria-current="page"]::after {
  transform: scaleX(1);
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple));
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 10px 9px;
  border: 1px solid var(--border-line);
  background: var(--base-dark);
  border-radius: 2px;
}

.nav-toggle-bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--text-primary);
  transition: transform .24s ease, opacity .24s ease, background-color .2s ease;
}

.nav-toggle:hover { border-color: var(--accent-cyan); }
.nav-toggle:hover .nav-toggle-bar { background: var(--accent-cyan); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(7px) 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(-7px) rotate(-45deg); }

.to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 900;
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  background: var(--panel-dark);
  border: 1px solid var(--border-line);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .25s ease, transform .25s ease, visibility .25s ease, color .2s ease, border-color .2s ease;
}

.to-top:hover { color: var(--accent-cyan); border-color: var(--accent-cyan); }
.to-top.is-visible { opacity: 1; visibility: visible; transform: none; }

.site-footer {
  position: relative;
  margin-top: 80px;
  background: #080E1A;
  border-top: 1px solid var(--border-line);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-purple), var(--accent-blue), var(--accent-cyan) 85%, transparent);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1.3fr;
  gap: 48px 56px;
  padding-block: 54px 36px;
}

.footer-brand-name { font-size: 25px; }

.footer-about {
  max-width: 42ch;
  margin-top: 14px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.8;
}

.footer-trust {
  max-width: 56ch;
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--border-line);
  color: var(--text-secondary);
  font-size: 11.5px;
  line-height: 1.8;
  letter-spacing: .04em;
}

.footer-heading {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--accent-blue);
}

.footer-nav-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px 18px;
}

.footer-nav-list a {
  display: inline-block;
  padding: 4px 0;
  font-size: 13.5px;
  color: var(--text-secondary);
}

.footer-nav-list a:hover { color: var(--accent-cyan); transform: translateX(2px); }

.footer-address {
  display: grid;
  gap: 10px;
  color: var(--text-secondary);
  font-size: 13.5px;
  line-height: 1.6;
}

.footer-address span::before { content: "▸ "; color: var(--accent-purple); }

.footer-support {
  margin-top: 18px;
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--text-secondary);
}

.footer-support::before { content: "MAIL·"; color: var(--accent-orange); font-weight: 700; }

.footer-legal {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--border-line);
  margin-top: 8px;
  padding-top: 24px;
}

.footer-legal a {
  padding: 3px 4px;
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--text-secondary);
}

.footer-legal a::before { content: "["; color: var(--border-line); }
.footer-legal a::after { content: "]"; color: var(--border-line); }
.footer-legal a:hover { color: var(--accent-cyan); }

.legal-sep { color: var(--border-line); font-size: 12px; }

.footer-bottom { border-top: 1px solid var(--border-line); }

.footer-bottom-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 20px;
  padding-block: 18px;
  color: var(--text-secondary);
  font-size: 12px;
}

.footer-copy, .footer-icp { font-size: 12px; }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 22px 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-secondary);
}

.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent-cyan); }
.breadcrumb [aria-current="page"] { color: var(--text-primary); }

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--accent-cyan);
}

.section-label::before { content: ""; width: 22px; height: 2px; background: var(--accent-purple); }

.index-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--text-secondary);
}

.index-label strong { color: var(--accent-orange); font-weight: 700; }

.panel {
  background: var(--panel-dark);
  border: 1px solid var(--border-line);
  padding: 28px;
}

.panel-accent { border-top: 2px solid var(--accent-blue); }

.panel-accent::before {
  content: "";
  display: block;
  width: 64px;
  height: 2px;
  margin-bottom: 18px;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue));
}

.media-frame {
  position: relative;
  display: grid;
  place-items: center;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--panel-dark);
  border: 1px solid var(--border-line);
}

.media-frame[data-ratio="4-3"] { aspect-ratio: 4 / 3; }
.media-frame[data-ratio="21-9"] { aspect-ratio: 21 / 9; }

.media-frame::before {
  content: attr(data-caption);
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 2;
  padding: 4px 8px;
  background: rgba(11, 18, 32, .72);
  border: 1px solid var(--border-line);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  color: var(--text-secondary);
}

.media-frame::after {
  content: "";
  position: absolute;
  right: -18px;
  bottom: -18px;
  width: 76px;
  height: 76px;
  background: linear-gradient(135deg, transparent 47%, var(--accent-blue) 48%, transparent 52%);
  opacity: .45;
}

.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

@media (max-width: 1024px) {
  .nav-list a { padding: 18px 10px; font-size: 13px; }
  .footer-top { gap: 38px 32px; }
}

@media (max-width: 880px) {
  .masthead-main { grid-template-columns: 1fr auto; padding-block: 22px 18px; }
  .brand { grid-column: 1; align-items: flex-start; }
  .brand-name { font-size: 24px; }
  .brand-sub { font-size: 10px; letter-spacing: .22em; }
  .masthead-actions { grid-column: 2; }
  .status-lamp { display: none; }
  .masthead-nav-inner { grid-template-columns: 1fr auto; min-height: 52px; }
  .nav-brand-inline { display: inline-block; }
  .main-nav { grid-column: 1 / -1; display: none; }
  .main-nav[data-open] { display: block; }
  .nav-list { flex-direction: column; align-items: stretch; gap: 0; padding: 6px 0 14px; }
  .nav-list a { padding: 13px 4px; font-size: 15px; border-bottom: 1px solid var(--border-line); }
  .nav-list a::after { display: none; }
  .nav-toggle { display: flex; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 600px) {
  .container { width: 92vw; }
  .masthead-meta-inner { min-height: 30px; }
  .masthead-main { padding-block: 16px 14px; }
  .brand-name { font-size: 21px; }
  .brand-sub { letter-spacing: .16em; }
  .btn-sm { padding: 8px 12px; font-size: 11px; }
  .footer-top { grid-template-columns: 1fr; padding-block: 40px 28px; gap: 30px; }
  .footer-legal { flex-direction: column; align-items: flex-start; gap: 6px; }
  .footer-bottom-inner { flex-direction: column; align-items: center; text-align: center; }
  .to-top { right: 14px; bottom: 14px; width: 42px; height: 42px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    transition-delay: 0s !important;
  }
}