:root {
  color-scheme: light;
  --paper: #f4f1e8;
  --paper-deep: #e9e4d7;
  --ink: #161b2c;
  --muted: #626570;
  --line: rgba(22, 27, 44, 0.18);
  --accent: #ff5c35;
  --accent-soft: rgba(255, 92, 53, 0.12);
  --card: rgba(255, 255, 255, 0.52);
  --shadow: 0 24px 80px rgba(29, 31, 45, 0.1);
  --max-width: 1180px;
  --grid-size: 72px;
  --hero-min: 4rem;
  --hero-fluid: 8.4vw;
  --hero-max: 7.8rem;
  --display-font: Georgia, "Times New Roman", "Songti SC", serif;
  --card-radius: 0px;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #111522;
  --paper-deep: #191e2d;
  --ink: #f3f0e7;
  --muted: #a7a9b2;
  --line: rgba(243, 240, 231, 0.16);
  --accent: #ff6d49;
  --accent-soft: rgba(255, 109, 73, 0.14);
  --card: rgba(255, 255, 255, 0.045);
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.24);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  margin: 0;
  overflow-x: hidden;
  background:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px),
    var(--paper);
  background-size: var(--grid-size) var(--grid-size);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Microsoft YaHei", sans-serif;
  transition: background-color 250ms ease, color 250ms ease;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  background: radial-gradient(circle at 78% 18%, var(--accent-soft), transparent 30%);
  content: "";
  pointer-events: none;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  color: inherit;
  font: inherit;
}

.skip-link {
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 20;
  padding: 0.75rem 1rem;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-180%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header,
.hero,
.section,
.footer {
  width: min(calc(100% - 48px), var(--max-width));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 96px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
}

.brand-domain {
  font-size: 0.9rem;
  letter-spacing: 0.04em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 30px;
  color: var(--muted);
  font-size: 0.9rem;
}

.nav a {
  position: relative;
}

.nav a::after {
  position: absolute;
  right: 0;
  bottom: -7px;
  left: 0;
  height: 1px;
  background: var(--accent);
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 180ms ease;
}

.nav a:hover::after,
.nav a:focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}

.theme-toggle {
  display: grid;
  width: 40px;
  height: 40px;
  padding: 0;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--card);
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--accent);
}

.theme-icon {
  font-size: 1.15rem;
  line-height: 1;
}

.hero {
  display: grid;
  min-height: calc(100svh - 96px);
  grid-template-columns: minmax(0, 1.35fr) minmax(290px, 0.65fr);
  gap: clamp(3rem, 9vw, 9rem);
  align-items: center;
  padding-block: 72px;
}

.eyebrow,
.section-index,
.card-label {
  margin: 0;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
}

.eyebrow b {
  font: inherit;
}

.eyebrow span {
  width: 26px;
  height: 2px;
  background: var(--accent);
}

.hero h1 {
  max-width: 780px;
  margin: 26px 0 28px;
  font-family: var(--display-font);
  font-size: clamp(var(--hero-min), var(--hero-fluid), var(--hero-max));
  font-weight: 400;
  letter-spacing: -0.065em;
  line-height: 0.9;
}

.hero h1 > span,
.section-content h2 {
  white-space: pre-line;
}

.hero h1 em {
  color: var(--accent);
  font-weight: 400;
}

.hero-intro {
  max-width: 610px;
  margin: 0;
  color: var(--muted);
  font-size: clamp(1rem, 1.6vw, 1.18rem);
  line-height: 1.85;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 42px;
}

.button {
  display: inline-flex;
  min-height: 52px;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  border: 1px solid var(--ink);
  border-radius: 999px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 700;
  transition: transform 180ms ease, background-color 180ms ease,
    color 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  background: var(--ink);
  color: var(--paper);
}

.button-secondary {
  background: transparent;
}

.button-secondary:hover {
  background: var(--accent-soft);
}

.signal-card {
  position: relative;
  min-height: 430px;
  overflow: hidden;
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: 220px 220px 28px 28px;
  background: var(--card);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.signal-orbit {
  position: absolute;
  top: 48%;
  left: 50%;
  display: grid;
  width: 245px;
  height: 245px;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.signal-orbit::before,
.signal-orbit::after {
  position: absolute;
  border: 1px solid var(--line);
  border-radius: 50%;
  content: "";
}

.signal-orbit::before {
  inset: 22px;
}

.signal-orbit::after {
  inset: 56px;
  background: var(--accent-soft);
}

.orbit-core {
  z-index: 1;
  font-family: Georgia, serif;
  font-size: 1.4rem;
  letter-spacing: 0.08em;
}

.orbit-dot {
  position: absolute;
  z-index: 2;
  top: 50%;
  left: 50%;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 8px var(--accent-soft);
  animation: orbit 10s linear infinite;
}

.signal-meta {
  position: absolute;
  right: 30px;
  bottom: 56px;
  left: 30px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.78rem;
}

.online {
  display: flex;
  align-items: center;
  gap: 7px;
  text-transform: uppercase;
}

.online i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #38a96b;
  box-shadow: 0 0 0 5px rgba(56, 169, 107, 0.12);
}

.local-time {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: 0.05em;
}

.signal-card > p {
  position: absolute;
  right: 30px;
  bottom: 28px;
  left: 30px;
  margin: 0;
  color: var(--muted);
  font-size: 0.75rem;
  text-align: right;
}

.section {
  border-top: 1px solid var(--line);
  padding-block: clamp(80px, 12vw, 150px);
}

.about {
  display: grid;
  grid-template-columns: 0.42fr 1fr;
  gap: 3rem;
}

.section-content h2,
.section-heading h2 {
  margin: 0;
  font-family: var(--display-font);
  font-size: clamp(2.5rem, 5.6vw, 5.6rem);
  font-weight: 400;
  letter-spacing: -0.045em;
  line-height: 1.04;
}

.section-content > p {
  max-width: 650px;
  margin: 42px 0 0;
  color: var(--muted);
  font-size: 1.08rem;
  line-height: 1.9;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 58px;
}

.status-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.status-card {
  position: relative;
  min-height: 330px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--card-radius);
  background: var(--card);
  transition: border-color 180ms ease, transform 180ms ease,
    background-color 180ms ease;
}

.status-card:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateY(-6px);
}

.card-number {
  position: absolute;
  top: 24px;
  right: 26px;
  color: var(--muted);
  font-family: Georgia, serif;
  font-size: 1.8rem;
  font-style: italic;
}

.status-card h3 {
  margin: 114px 0 18px;
  font-family: var(--display-font);
  font-size: 1.85rem;
  font-weight: 400;
}

.status-card > p:last-child {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.footer {
  display: flex;
  min-height: 120px;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
}

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

.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  z-index: 10;
  padding: 12px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.84rem;
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 18px);
  transition: opacity 180ms ease, transform 180ms ease;
}

.toast.is-visible {
  opacity: 1;
  transform: translate(-50%, 0);
}

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 700ms ease, transform 700ms ease;
}

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

@keyframes orbit {
  from {
    transform: translate(-50%, -50%) rotate(0deg) translateX(122px);
  }
  to {
    transform: translate(-50%, -50%) rotate(360deg) translateX(122px);
  }
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 64px;
  }

  .signal-card {
    min-height: 390px;
  }

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

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

  .status-card {
    min-height: 260px;
  }

  .status-card h3 {
    margin-top: 84px;
  }
}

@media (max-width: 560px) {
  .site-header,
  .hero,
  .section,
  .footer {
    width: min(calc(100% - 32px), var(--max-width));
  }

  .site-header {
    height: 78px;
  }

  .brand-domain,
  .nav a {
    display: none;
  }

  .hero {
    min-height: auto;
    padding-block: 70px 88px;
  }

  .hero h1 {
    font-size: clamp(3.4rem, 17vw, 5.2rem);
  }

  .hero-actions,
  .button {
    width: 100%;
  }

  .signal-card {
    min-height: 350px;
    padding: 22px;
  }

  .signal-meta,
  .signal-card > p {
    right: 22px;
    left: 22px;
  }

  .section-heading {
    display: block;
  }

  .section-heading h2 {
    margin-top: 18px;
  }

  .footer {
    min-height: 112px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}

:root[data-motion="off"] *,
:root[data-motion="off"] *::before,
:root[data-motion="off"] *::after {
  animation-duration: 0.01ms !important;
  animation-iteration-count: 1 !important;
  scroll-behavior: auto !important;
  transition-duration: 0.01ms !important;
}