:root {
  --bg: #06101d;
  --bg-soft: #0a1727;
  --panel: rgba(13, 29, 48, 0.72);
  --line: rgba(255, 255, 255, 0.12);
  --text: #f4f7fb;
  --muted: #9aa9bb;
  --accent: #d9b86c;
  --accent-strong: #f0cf80;
  --max: 1180px;
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background:
    radial-gradient(circle at 75% 5%, rgba(36, 78, 124, 0.20), transparent 34rem),
    linear-gradient(180deg, #07111f 0%, #050b14 100%);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

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

.shell {
  width: min(calc(100% - 40px), var(--max));
  margin-inline: auto;
}

.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;
}

.skip-link {
  position: fixed;
  z-index: 100;
  left: 16px;
  top: -60px;
  padding: 10px 14px;
  border-radius: 8px;
  color: var(--bg);
  background: var(--text);
  text-decoration: none;
}

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

/* Header */
.site-header {
  position: fixed;
  z-index: 20;
  inset: 0 0 auto;
  border-bottom: 1px solid transparent;
  transition: background 200ms ease, border-color 200ms ease, backdrop-filter 200ms ease;
}

.site-header.is-scrolled {
  background: rgba(5, 11, 20, 0.82);
  border-color: var(--line);
  backdrop-filter: blur(18px);
}

.nav-wrap {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  text-decoration: none;
  font-weight: 800;
  letter-spacing: 0.16em;
}

.brand-mark {
  position: relative;
  width: 28px;
  height: 28px;
  flex: 0 0 auto;
  border: 1px solid var(--accent);
  border-radius: 50%;
}

.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  background: var(--accent);
}

.brand-mark::before {
  width: 1px;
  height: 16px;
  top: 5px;
  left: 13px;
}

.brand-mark::after {
  width: 16px;
  height: 1px;
  top: 13px;
  left: 5px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 18px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.site-nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  transition: color 160ms ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--text);
}

html[lang="zh-CN"] .site-nav a {
  letter-spacing: 0.08em;
}

.language-control {
  display: inline-flex;
  align-items: center;
}

.language-control select {
  min-width: 78px;
  height: 38px;
  padding: 0 30px 0 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text);
  background:
    linear-gradient(45deg, transparent 50%, var(--muted) 50%) calc(100% - 14px) 16px / 5px 5px no-repeat,
    linear-gradient(135deg, var(--muted) 50%, transparent 50%) calc(100% - 10px) 16px / 5px 5px no-repeat,
    rgba(255,255,255,.035);
  appearance: none;
  font: inherit;
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  cursor: pointer;
  outline: none;
}

.language-control select:hover,
.language-control select:focus-visible {
  border-color: rgba(217,184,108,.5);
}

.language-control select option {
  color: #111827;
  background: #fff;
}

.nav-toggle {
  display: none;
}

/* Hero */
.hero {
  position: relative;
  min-height: 720px;
  padding: 145px 0 90px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.025) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: linear-gradient(to bottom, black, transparent 88%);
}

.stars,
.stars::before,
.stars::after {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-repeat: repeat;
}

.stars {
  opacity: .55;
  background-image: radial-gradient(circle, rgba(255,255,255,.75) 0 1px, transparent 1.2px);
  background-size: 113px 97px;
}

.stars::before,
.stars::after {
  content: "";
}

.stars::before {
  background-image: radial-gradient(circle, rgba(217,184,108,.9) 0 1px, transparent 1.3px);
  background-size: 179px 131px;
  transform: translate(39px, 19px);
}

.stars::after {
  opacity: .45;
  background-image: radial-gradient(circle, rgba(167,207,255,.9) 0 1px, transparent 1.2px);
  background-size: 227px 173px;
  transform: translate(91px, 63px);
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(390px, .94fr);
  gap: clamp(52px, 6vw, 82px);
  align-items: center;
}

.hero-copy {
  min-width: 0;
}

.eyebrow,
.section-kicker {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: .76rem;
  font-weight: 800;
  letter-spacing: .2em;
}

html[lang="zh-CN"] .eyebrow,
html[lang="zh-CN"] .section-kicker {
  letter-spacing: .12em;
}

.hero h1 {
  margin: 0;
  white-space: nowrap;
  font-family: "Arial Black", "Helvetica Neue", Arial, sans-serif;
  font-size: clamp(5rem, 6.8vw, 7rem);
  line-height: .9;
  letter-spacing: .018em;
  text-transform: uppercase;
  background: linear-gradient(180deg, #fff 0%, #d1d8e1 62%, #8d9aaa 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 18px 50px rgba(0,0,0,.35);
}

.hero-subtitle {
  margin: 28px 0 22px;
  font-size: clamp(1rem, 2vw, 1.25rem);
  font-weight: 700;
  letter-spacing: .3em;
}

html[lang="zh-CN"] .hero-subtitle {
  letter-spacing: .18em;
}

.hero-subtitle span {
  color: var(--accent);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 32px;
}

.hero-meta span {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .1em;
}

html[lang="zh-CN"] .hero-meta span {
  letter-spacing: .025em;
}

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

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: 999px;
  text-decoration: none;
  font-size: .86rem;
  font-weight: 800;
  letter-spacing: .03em;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
}

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

.button-primary {
  color: #111827;
  background: var(--accent-strong);
}

.button-primary:hover {
  background: #ffe19a;
}

.button-ghost {
  border-color: var(--line);
  background: rgba(255,255,255,.035);
}

.button-ghost:hover {
  border-color: rgba(255,255,255,.28);
  background: rgba(255,255,255,.06);
}

.signal-card {
  position: relative;
  min-height: 405px;
  padding: 28px;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,.13);
  border-radius: 30px;
  background:
    linear-gradient(145deg, rgba(255,255,255,.08), rgba(255,255,255,.015)),
    rgba(5,15,28,.62);
  box-shadow:
    0 34px 80px rgba(0,0,0,.38),
    inset 0 1px rgba(255,255,255,.09);
  backdrop-filter: blur(14px);
}

.signal-card::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 82% 18%, rgba(217,184,108,.17), transparent 33%),
    linear-gradient(transparent 49%, rgba(255,255,255,.035) 50%, transparent 51%);
  background-size: auto, 100% 24px;
}

.signal-topline {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: .72rem;
  font-weight: 800;
  letter-spacing: .18em;
}

.signal-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 18px var(--accent);
}

.spectrum {
  position: relative;
  z-index: 2;
  height: 116px;
  margin: 52px 0 35px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.spectrum span {
  flex: 1;
  height: var(--h);
  min-height: 5px;
  border-radius: 999px;
  background: linear-gradient(to top, rgba(217,184,108,.3), var(--accent-strong));
  box-shadow: 0 0 20px rgba(217,184,108,.15);
  animation: pulse 2.8s ease-in-out infinite alternate;
}

.spectrum span:nth-child(2n) { animation-delay: -.6s; }
.spectrum span:nth-child(3n) { animation-delay: -1.2s; }

@keyframes pulse {
  to {
    transform: scaleY(.62);
    opacity: .62;
  }
}

.signal-readout {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.signal-readout div {
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.signal-readout small,
.signal-readout strong {
  display: block;
}

.signal-readout small {
  color: var(--muted);
  font-size: .66rem;
  letter-spacing: .14em;
}

.signal-readout strong {
  margin-top: 3px;
  font-size: .96rem;
  letter-spacing: .06em;
}

.antenna {
  position: absolute;
  right: 32px;
  bottom: 20px;
  width: 150px;
  height: 120px;
  opacity: .25;
}

.mast,
.beam,
.wave {
  position: absolute;
  display: block;
}

.mast {
  left: 73px;
  bottom: 0;
  width: 2px;
  height: 88px;
  background: var(--text);
  transform: skewX(-5deg);
}

.beam {
  left: 32px;
  width: 84px;
  height: 1px;
  background: var(--text);
}

.beam-a {
  top: 40px;
  transform: rotate(14deg);
}

.beam-b {
  top: 58px;
  transform: rotate(-12deg);
}

.wave {
  border: 1px solid var(--accent);
  border-left-color: transparent;
  border-bottom-color: transparent;
  border-radius: 50%;
  transform: rotate(45deg);
}

.wave-a {
  width: 28px;
  height: 28px;
  right: 40px;
  top: 17px;
}

.wave-b {
  width: 48px;
  height: 48px;
  right: 28px;
  top: 5px;
}

.wave-c {
  width: 70px;
  height: 70px;
  right: 16px;
  top: -7px;
}

.hero-rule {
  position: absolute;
  inset: auto 0 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(217,184,108,.55), transparent);
}

/* Main sections */
.section {
  padding: 104px 0;
  border-bottom: 1px solid var(--line);
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
  gap: clamp(58px, 7vw, 92px);
  align-items: start;
}

.section h2 {
  margin: 0;
  max-width: 100%;
  line-height: 1.08;
  letter-spacing: -.035em;
}

.about-grid {
  align-items: center;
}

html[lang="en"] #about h2 {
  font-size: clamp(2.55rem, 3.1vw, 3.08rem);
  white-space: nowrap;
}

html[lang="zh-CN"] #about h2 {
  font-size: clamp(2.65rem, 3.45vw, 3.4rem);
  line-height: 1.16;
  letter-spacing: -.025em;
  white-space: pre-line;
}

.body-copy {
  color: #bcc7d4;
  font-size: clamp(1rem, 1.3vw, 1.1rem);
  line-height: 1.72;
}

.body-copy p {
  margin: 0 0 1.25em;
}

.body-copy p:last-child {
  margin-bottom: 0;
}

.section-panel {
  background: rgba(255,255,255,.018);
}

/* Station cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.info-card {
  min-height: 205px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(155deg, rgba(255,255,255,.055), transparent 45%),
    var(--panel);
  transition: transform 180ms ease, border-color 180ms ease;
}

.info-card:hover {
  transform: translateY(-4px);
  border-color: rgba(217,184,108,.34);
}

.card-index {
  display: inline-grid;
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
  place-items: center;
  border: 1px solid rgba(217,184,108,.45);
  border-radius: 50%;
  color: var(--accent);
  font-size: .75rem;
  font-weight: 800;
}

.card-content {
  margin-top: 30px;
  padding-top: 0;
}

.info-card h3 {
  margin: 0 0 9px;
  font-size: 1.28rem;
}

.info-card p {
  margin: 0;
  color: var(--muted);
}

/* QSL */
.qsl-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr);
  align-items: center;
  gap: clamp(58px, 7vw, 92px);
}

#qsl h2 {
  margin: 0;
  font-size: clamp(2.45rem, 3.15vw, 3.05rem);
  line-height: 1.08;
  letter-spacing: -.03em;
  white-space: nowrap;
}

.text-link {
  display: inline-flex;
  gap: 8px;
  align-items: center;
  margin-top: 18px;
  color: var(--accent-strong);
  font-weight: 800;
  text-decoration: none;
  border-bottom: 1px solid rgba(217,184,108,.35);
}

.external-arrow {
  font-family: Arial, sans-serif;
  line-height: 1;
}

.qsl-card {
  width: 100%;
  aspect-ratio: 1.62 / 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(24px, 4vw, 42px);
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 26px;
  background:
    radial-gradient(circle at 78% 18%, rgba(217,184,108,.18), transparent 31%),
    linear-gradient(135deg, #0d2237, #08111e 70%);
  box-shadow: 0 30px 70px rgba(0,0,0,.38);
}

.qsl-card-top,
.qsl-card-bottom {
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: .68rem;
  font-weight: 800;
  letter-spacing: .16em;
}

.qsl-card strong {
  margin-top: auto;
  white-space: nowrap;
  font-family: "Arial Black", "Helvetica Neue", Arial, sans-serif;
  font-size: clamp(2.8rem, 5.4vw, 4.75rem);
  line-height: 1;
  letter-spacing: .02em;
}

.qsl-card p {
  margin: 10px 0 auto;
  color: var(--accent);
  font-size: .74rem;
  font-weight: 800;
  letter-spacing: .18em;
}

html[lang="zh-CN"] .qsl-card p,
html[lang="zh-CN"] .qsl-card-top,
html[lang="zh-CN"] .qsl-card-bottom {
  letter-spacing: .06em;
}

/* Contact */
.contact-section {
  background: radial-gradient(circle at 15% 50%, rgba(217,184,108,.07), transparent 28rem);
}

.contact-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
  gap: clamp(58px, 7vw, 92px);
  align-items: center;
}

#contact h2 {
  margin: 0;
  font-size: clamp(2.5rem, 3.25vw, 3.15rem);
  line-height: 1.1;
  letter-spacing: -.03em;
}

html[lang="zh-CN"] #contact h2 {
  white-space: nowrap;
}

.contact-links {
  display: grid;
  align-content: center;
}

.contact-links a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 25px;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
}

.contact-links span {
  color: var(--muted);
  font-size: .75rem;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.contact-links strong {
  text-align: right;
}

/* Footer */
.site-footer {
  padding: 28px 0;
  color: var(--muted);
  font-size: .82rem;
}

.footer-wrap {
  display: flex;
  justify-content: space-between;
  gap: 20px;
}

.footer-wrap strong {
  color: var(--text);
  letter-spacing: .08em;
}

/* Medium screens / tablets */
@media (max-width: 980px) {
  .hero {
    min-height: auto;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 52px;
  }

  .signal-card {
    min-height: 355px;
  }

  .section-grid,
  .qsl-grid,
  .contact-wrap {
    grid-template-columns: 1fr;
  }

  html[lang="en"] #about h2 {
    white-space: normal;
  }

  html[lang="zh-CN"] #contact h2,
  #qsl h2 {
    white-space: normal;
  }

  .card-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .info-card {
    min-height: 0;
    padding: 24px;
  }

  .card-content {
    margin-top: 0;
    padding-top: 32px;
  }

  .qsl-card {
    max-width: 620px;
  }
}

/* Mobile */
@media (max-width: 680px) {
  .shell {
    width: min(calc(100% - 28px), var(--max));
  }

  .nav-wrap {
    min-height: 68px;
  }

  .brand {
    gap: 10px;
    letter-spacing: .13em;
  }

  .header-actions {
    gap: 10px;
  }

  .nav-toggle {
    display: inline-flex;
    width: 42px;
    height: 42px;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 6px;
    border: 1px solid var(--line);
    border-radius: 50%;
    background: rgba(255,255,255,.03);
  }

  .nav-toggle span:not(.sr-only) {
    width: 17px;
    height: 1px;
    background: var(--text);
  }

  .site-nav {
    position: absolute;
    top: 68px;
    left: 14px;
    right: 14px;
    display: none;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: rgba(5,11,20,.96);
    backdrop-filter: blur(18px);
  }

  .site-nav.is-open {
    display: grid;
    gap: 6px;
  }

  .site-nav a {
    padding: 11px 8px;
  }

  .language-control select {
    min-width: 72px;
    height: 42px;
  }

  .hero {
    padding: 118px 0 72px;
  }

  .hero-grid {
    gap: 44px;
  }

  .hero h1 {
    font-size: clamp(3.55rem, 18vw, 5rem);
    line-height: .9;
    letter-spacing: .012em;
  }

  .hero-subtitle {
    margin: 24px 0 18px;
    font-size: .98rem;
    letter-spacing: .16em;
  }

  .hero-meta {
    margin-bottom: 26px;
  }

  .hero-meta span {
    padding: 7px 10px;
    font-size: .68rem;
  }

  .button {
    min-height: 44px;
    padding: 0 16px;
    font-size: .8rem;
  }

  .signal-card {
    min-height: 325px;
    padding: 22px;
    border-radius: 24px;
  }

  .spectrum {
    gap: 5px;
    margin: 44px 0 30px;
  }

  .section {
    padding: 72px 0;
  }

  .section-kicker {
    margin-bottom: 16px;
  }

  html[lang="en"] #about h2 {
    font-size: clamp(2.05rem, 9.4vw, 2.65rem);
    line-height: 1.1;
  }

  html[lang="zh-CN"] #about h2 {
    font-size: clamp(2.05rem, 9.2vw, 2.6rem);
    line-height: 1.18;
    white-space: pre-line;
  }

  .body-copy {
    font-size: 1rem;
    line-height: 1.72;
  }

  .body-copy p {
    margin-bottom: 1.2em;
  }

  .info-card {
    padding: 22px;
    border-radius: 21px;
  }

  .card-index {
    width: 34px;
    height: 34px;
  }

  .card-content {
    padding-top: 26px;
  }

  .info-card h3 {
    font-size: 1.22rem;
  }

  #qsl h2 {
    font-size: clamp(1.95rem, 8.5vw, 2.4rem);
    line-height: 1.08;
    white-space: nowrap;
  }

  .text-link {
    margin-top: 14px;
    font-size: .95rem;
  }

  .qsl-card {
    margin-top: 8px;
    padding: 25px;
    border-radius: 20px;
  }

  .qsl-card strong {
    font-size: clamp(2.7rem, 13.5vw, 4rem);
  }

  .qsl-card p {
    font-size: .69rem;
  }

  #contact h2 {
    font-size: clamp(2rem, 9vw, 2.55rem);
    line-height: 1.15;
  }

  html[lang="zh-CN"] #contact h2 {
    white-space: normal;
  }

  .contact-links strong {
    max-width: 68%;
    overflow-wrap: anywhere;
  }

  .footer-wrap {
    flex-direction: column;
  }
}

@media (max-width: 390px) {
  .brand {
    font-size: .92rem;
  }

  .hero h1 {
    font-size: clamp(3.2rem, 16.8vw, 4.55rem);
  }

  #qsl h2 {
    font-size: 1.82rem;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}