:root {
  color-scheme: dark;
  --bg: #070a12;
  --panel: rgba(15, 23, 42, 0.72);
  --panel-strong: rgba(15, 23, 42, 0.88);
  --line: rgba(255, 255, 255, 0.12);
  --line-strong: rgba(103, 232, 249, 0.34);
  --text: #f8fafc;
  --muted: #9aa8bd;
  --soft: #cbd5e1;
  --cyan: #22d3ee;
  --teal: #2dd4bf;
  --rose: #fb7185;
  --green: #86efac;
  --shadow: 0 28px 90px rgba(0, 0, 0, 0.34);
  --radius: 18px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 12% 10%, rgba(34, 211, 238, 0.18), transparent 30rem),
    radial-gradient(circle at 82% 0%, rgba(251, 113, 133, 0.15), transparent 28rem),
    radial-gradient(circle at 50% 85%, rgba(45, 212, 191, 0.10), transparent 34rem),
    linear-gradient(135deg, #070a12 0%, #0e1424 48%, #070a12 100%);
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: linear-gradient(to bottom, rgba(0,0,0,0.7), transparent 72%);
}

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

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

.site-shell {
  position: relative;
  width: min(1240px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 14px;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin: 14px 0 0;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(7, 10, 18, 0.72);
  box-shadow: 0 20px 70px rgba(0, 0, 0, 0.28);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: max-content;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--cyan), var(--rose));
  color: #fff;
  font-weight: 900;
  box-shadow: 0 18px 52px rgba(34, 211, 238, 0.24);
}

.brand-name {
  font-size: 18px;
  font-weight: 850;
  letter-spacing: 0;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.main-nav a {
  border-radius: 12px;
  padding: 10px 13px;
  color: var(--soft);
  font-size: 14px;
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.main-nav a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-1px);
}

.language-switcher select {
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  padding: 0 12px;
  outline: none;
}

.hero-section {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(380px, 0.95fr);
  gap: 28px;
  align-items: center;
  min-height: calc(100vh - 96px);
  padding: 58px 0 44px;
}

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

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  border: 1px solid rgba(103, 232, 249, 0.26);
  border-radius: 999px;
  background: rgba(103, 232, 249, 0.10);
  color: #cffafe;
  font-size: 14px;
  font-weight: 700;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: var(--green);
  box-shadow: 0 0 0 6px rgba(134, 239, 172, 0.12);
}

.hero-section h1 {
  max-width: 780px;
  margin: 22px 0 18px;
  font-size: clamp(42px, 5.8vw, 74px);
  line-height: 1.03;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 720px;
  margin: 0;
  color: var(--soft);
  font-size: 18px;
  line-height: 1.9;
}

.download-console {
  display: flex;
  gap: 12px;
  margin-top: 30px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(15, 23, 42, 0.68);
  box-shadow: var(--shadow);
  backdrop-filter: blur(20px);
}

.url-field {
  position: relative;
  flex: 1;
  min-width: 0;
}

.link-icon {
  position: absolute;
  left: 18px;
  top: 50%;
  display: grid;
  width: 22px;
  height: 22px;
  transform: translateY(-50%);
  color: #7dd3fc;
  opacity: 0.9;
}

.link-icon svg {
  width: 22px;
  height: 22px;
}

.url-field input,
.select-label select {
  width: 100%;
  height: 60px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 14px;
  outline: none;
  background: rgba(255, 255, 255, 0.07);
  color: #fff;
  transition: border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.url-field input {
  padding: 0 18px 0 52px;
}

.url-field input::placeholder {
  color: rgba(203, 213, 225, 0.56);
}

.url-field input:focus,
.select-label select:focus {
  border-color: rgba(103, 232, 249, 0.72);
  background: rgba(255, 255, 255, 0.10);
  box-shadow: 0 0 0 4px rgba(34, 211, 238, 0.10);
}

.gradient-button,
.success-button {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 60px;
  border: 0;
  border-radius: 14px;
  padding: 0 26px;
  overflow: hidden;
  background: linear-gradient(90deg, var(--cyan), var(--teal), var(--rose));
  color: #fff;
  font-weight: 850;
  box-shadow: 0 20px 64px rgba(34, 211, 238, 0.20);
  transition: transform 0.2s ease, filter 0.2s ease, box-shadow 0.2s ease;
}

.gradient-button:hover,
.success-button:hover {
  transform: translateY(-2px);
  filter: brightness(1.08);
  box-shadow: 0 26px 72px rgba(251, 113, 133, 0.20);
}

.gradient-button:disabled {
  cursor: not-allowed;
  opacity: 0.68;
  transform: none;
}

.button-spinner {
  display: none;
  width: 18px;
  height: 18px;
  margin-left: 10px;
  border: 2px solid rgba(255,255,255,0.42);
  border-top-color: #fff;
  border-radius: 999px;
  animation: spin 0.8s linear infinite;
}

.is-loading .button-spinner {
  display: inline-block;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 22px;
}

.hero-stats div {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 16px;
  background: rgba(255, 255, 255, 0.045);
}

.hero-stats strong {
  display: block;
  font-size: 22px;
}

.hero-stats span {
  display: block;
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
}

.result-panel {
  position: relative;
  min-height: 590px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--panel);
  box-shadow: var(--shadow);
  overflow: hidden;
  backdrop-filter: blur(22px);
}

.panel-glow {
  position: absolute;
  inset: -35% -20% auto auto;
  width: 280px;
  height: 280px;
  border-radius: 999px;
  background: rgba(34, 211, 238, 0.16);
  filter: blur(40px);
  pointer-events: none;
}

.empty-preview {
  position: relative;
  display: grid;
  min-height: 548px;
  place-items: center;
  align-content: center;
  border: 1px dashed rgba(255, 255, 255, 0.16);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.035);
  text-align: center;
  padding: 28px;
}

.preview-icon {
  width: 76px;
  height: 76px;
  border-radius: 22px;
  background:
    linear-gradient(135deg, rgba(34,211,238,.28), rgba(251,113,133,.22)),
    rgba(255,255,255,.08);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.16);
}

.empty-preview h2 {
  margin: 20px 0 8px;
  font-size: 24px;
}

.empty-preview p {
  max-width: 360px;
  margin: 0;
  color: var(--muted);
  line-height: 1.8;
}

.video-preview {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(2, 6, 23, 0.8);
}

.video-preview img,
.no-thumb {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.no-thumb {
  display: grid;
  place-items: center;
  color: var(--muted);
}

.result-content {
  position: relative;
  padding: 18px 2px 2px;
}

.result-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.result-meta span,
.platform-grid article,
.feature-grid article,
.steps-grid article,
.faq-list details,
.task-card,
.notice-card {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.055);
  backdrop-filter: blur(16px);
}

.result-meta span {
  border-radius: 999px;
  padding: 8px 11px;
  color: #dbeafe;
  font-size: 13px;
  font-weight: 700;
}

.result-content h2 {
  margin: 14px 0 16px;
  font-size: 24px;
  line-height: 1.35;
}

.download-tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 12px;
}

.download-tabs button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--soft);
  font-weight: 800;
  transition: border-color 0.2s ease, background 0.2s ease, color 0.2s ease;
}

.download-tabs button.active {
  border-color: var(--line-strong);
  background: rgba(34, 211, 238, 0.14);
  color: #cffafe;
}

.select-label {
  display: grid;
  gap: 8px;
  margin: 10px 0 12px;
  color: var(--soft);
  font-size: 14px;
  font-weight: 750;
}

.select-label select {
  padding: 0 14px;
  color: #fff;
}

.full-width {
  width: 100%;
}

.task-card {
  margin-top: 14px;
  border-radius: 16px;
  padding: 16px;
}

.task-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 12px;
}

.progress-track {
  height: 9px;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.10);
}

.progress-track i {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--cyan), var(--rose));
  transition: width 0.28s ease;
}

.success-button {
  width: 100%;
  margin-top: 14px;
  background: linear-gradient(90deg, #34d399, #67e8f9);
  color: #04111d;
}

.notice-card {
  border-radius: 14px;
  padding: 14px 16px;
  line-height: 1.7;
}

.notice-card.error {
  border-color: rgba(251, 113, 133, 0.34);
  background: rgba(251, 113, 133, 0.12);
  color: #ffe4e6;
}

.hidden {
  display: none !important;
}

.section-block {
  padding: 42px 0;
}

.section-heading {
  margin-bottom: 20px;
}

.section-heading span {
  color: #67e8f9;
  font-size: 13px;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.section-heading h2 {
  margin: 8px 0 0;
  font-size: clamp(28px, 3vw, 42px);
  line-height: 1.18;
}

.platform-grid,
.feature-grid,
.steps-grid {
  display: grid;
  gap: 16px;
}

.platform-grid {
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
}

.feature-grid {
  grid-template-columns: repeat(4, 1fr);
}

.steps-grid {
  grid-template-columns: repeat(3, 1fr);
}

.platform-grid article,
.feature-grid article,
.steps-grid article,
.faq-list details {
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 16px 58px rgba(0, 0, 0, 0.18);
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.platform-grid article:hover,
.feature-grid article:hover,
.steps-grid article:hover,
.faq-list details:hover {
  transform: translateY(-3px);
  border-color: var(--line-strong);
  background: rgba(255, 255, 255, 0.075);
}

.platform-grid b,
.feature-grid h3,
.steps-grid h3 {
  display: block;
  margin: 0 0 10px;
  font-size: 19px;
}

.platform-grid p,
.feature-grid p,
.steps-grid p,
.faq-list p {
  margin: 0;
  color: var(--muted);
  line-height: 1.8;
}

.step-number {
  display: inline-grid;
  place-items: center;
  width: 46px;
  height: 46px;
  margin-bottom: 18px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.08);
  color: #cffafe;
  font-weight: 900;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-list summary {
  cursor: pointer;
  font-weight: 850;
}

.faq-list p {
  margin-top: 12px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 26px;
  padding: 28px 0 42px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

.page-hero {
  padding: 72px 0 34px;
}

.page-hero h1 {
  margin: 0 0 14px;
  font-size: clamp(38px, 5vw, 62px);
  line-height: 1.08;
}

.page-hero p {
  max-width: 760px;
  margin: 0;
  color: var(--soft);
  font-size: 18px;
  line-height: 1.9;
}

.content-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  background: var(--panel);
  box-shadow: var(--shadow);
  color: var(--soft);
  line-height: 1.9;
}

.content-card h2 {
  color: #fff;
}

.installer-page {
  display: grid;
  min-height: 100vh;
  place-items: center;
  padding: 24px;
}

.installer-shell {
  width: min(980px, 100%);
}

.installer-card {
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--panel-strong);
  box-shadow: var(--shadow);
  padding: 28px;
  backdrop-filter: blur(22px);
}

.installer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
}

.installer-brand strong {
  font-size: 22px;
}

.installer-progress {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
  margin-bottom: 26px;
}

.install-step {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 12px;
  background: rgba(255,255,255,.045);
  color: var(--muted);
}

.install-step span {
  display: grid;
  width: 28px;
  height: 28px;
  place-items: center;
  border-radius: 999px;
  background: rgba(255,255,255,.08);
  font-weight: 900;
}

.install-step b {
  display: block;
  margin-top: 8px;
  font-size: 13px;
}

.install-step.active,
.install-step.done {
  border-color: var(--line-strong);
  background: rgba(34,211,238,.11);
  color: #fff;
}

.installer-card h1 {
  margin: 0 0 10px;
  font-size: clamp(28px, 4vw, 44px);
}

.installer-help {
  margin: 0 0 20px;
  color: var(--muted);
  line-height: 1.8;
}

.env-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.env-item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 10px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 13px;
  background: rgba(255,255,255,.05);
}

.env-item i {
  display: grid;
  width: 26px;
  height: 26px;
  place-items: center;
  border-radius: 999px;
  font-style: normal;
  font-weight: 900;
}

.env-item.pass i {
  background: rgba(134,239,172,.16);
  color: var(--green);
}

.env-item.fail i {
  background: rgba(251,113,133,.16);
  color: var(--rose);
}

.env-item small {
  grid-column: 2 / -1;
  color: var(--muted);
}

.install-action {
  margin-top: 18px;
}

.installer-form {
  display: grid;
  gap: 14px;
}

.installer-form.two {
  grid-template-columns: repeat(2, 1fr);
}

.installer-form label {
  display: grid;
  gap: 8px;
  color: var(--soft);
  font-weight: 750;
}

.installer-form input {
  height: 54px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: rgba(255,255,255,.07);
  color: #fff;
  padding: 0 14px;
  outline: none;
}

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

.ghost-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 60px;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 0 24px;
  background: rgba(255,255,255,.08);
  color: #fff;
  font-weight: 850;
}

.disabled {
  pointer-events: none;
  opacity: .46;
}

@media (max-width: 980px) {
  .hero-section,
  .platform-grid,
  .feature-grid,
  .steps-grid {
    grid-template-columns: 1fr;
  }

  .hero-section {
    min-height: 0;
  }

  .result-panel {
    min-height: auto;
  }

  .empty-preview {
    min-height: 340px;
  }

  .download-console,
  .site-footer {
    flex-direction: column;
  }
}

@media (max-width: 720px) {
  .site-shell {
    width: min(100% - 22px, 1240px);
  }

  .site-header {
    top: 8px;
    align-items: flex-start;
  }

  .main-nav {
    display: none;
  }

  .language-switcher {
    margin-left: auto;
  }

  .installer-progress,
  .env-grid,
  .installer-form.two {
    grid-template-columns: 1fr;
  }

  .hero-section {
    padding-top: 42px;
  }

  .hero-stats,
  .download-tabs {
    grid-template-columns: 1fr;
  }

  .hero-section h1 {
    font-size: 40px;
  }
}