:root {
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --bg-muted: #f3f6fb;
  --text: #111827;
  --text-soft: #475569;
  --text-inverse: #f8fafc;
  --border: #dbe3ef;
  --primary: #ffd64d;
  --primary-dark: #e7bd2d;
  --panel: #ffffff;
  --shadow: 0 18px 40px rgba(15, 23, 42, 0.08);
  --radius: 20px;
  --container: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

img,
svg {
  display: block;
  max-width: 100%;
}

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

.container {
  width: min(calc(100% - 32px), var(--container));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(17, 24, 39, 0.92);
  backdrop-filter: blur(12px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

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

.brand-logo {
  width: auto;
  height: 34px;
}

.brand-text {
  font-size: 1.15rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 20px;
  color: rgba(255, 255, 255, 0.88);
  font-size: 0.95rem;
}

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

.header-download,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-radius: 999px;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
}

.header-download {
  padding: 10px 18px;
  background: var(--primary);
  color: #111;
}

.header-download img,
.button img {
  width: 18px;
  height: 18px;
}

.header-download:hover,
.button:hover {
  transform: translateY(-1px);
}

.hero {
  color: var(--text-inverse);
  background: linear-gradient(135deg, #111827, #1f2937 55%, #020617);
}

.hero-inner {
  padding: 96px 0 88px;
  text-align: center;
}

.hero-icon {
  width: 104px;
  height: 104px;
  margin: 0 auto 28px;
  padding: 24px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 28px;
  color: #fff;
  background: rgba(255, 255, 255, 0.08);
  box-shadow: var(--shadow);
}

.hero h1,
.section h2 {
  margin: 0;
  line-height: 1.2;
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 4.6rem);
}

.hero-copy {
  width: min(100%, 760px);
  margin: 22px auto 0;
  font-size: clamp(1.05rem, 2.2vw, 1.4rem);
  color: rgba(255, 255, 255, 0.84);
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.hero-tags li {
  padding: 10px 16px;
  border: 1px solid rgba(255, 214, 77, 0.35);
  border-radius: 999px;
  color: var(--primary);
  background: rgba(255, 214, 77, 0.12);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  margin-top: 34px;
}

.button {
  min-width: 220px;
  padding: 15px 24px;
  border: 2px solid transparent;
  font-size: 1rem;
}

.button-primary {
  background: var(--primary);
  color: #111;
  box-shadow: 0 18px 40px rgba(255, 214, 77, 0.2);
}

.button-primary:hover {
  background: var(--primary-dark);
}

.button-secondary {
  border-color: var(--primary);
  color: var(--primary);
  background: transparent;
}

.button-secondary:hover {
  background: rgba(255, 214, 77, 0.12);
}

.section {
  padding: 72px 0;
}

.section-muted {
  background: linear-gradient(180deg, var(--bg-soft), #eef4ff);
}

.section-soft {
  background: #f8fafc;
}

.section-dark {
  color: var(--text-inverse);
  background: linear-gradient(135deg, #111827, #1f2937 55%, #020617);
  text-align: center;
}

.section h2 {
  margin-bottom: 34px;
  text-align: center;
  font-size: clamp(1.9rem, 3vw, 2.4rem);
}

.two-column,
.stats {
  display: grid;
  gap: 24px;
}

.two-column {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.panel,
.feature-card,
.faq-item,
.notice {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.panel {
  padding: 28px;
}

.panel-highlight {
  background: linear-gradient(180deg, #f8fbff, #edf5ff);
  border-color: #bcd2ff;
}

.panel h3,
.feature-card h3,
.step-item h3,
.notice h3,
.faq-item h3 {
  margin-top: 0;
  margin-bottom: 12px;
  font-size: 1.2rem;
}

.spec-list,
.notice ul {
  margin: 0;
  padding-left: 18px;
  color: var(--text-soft);
}

.spec-list li,
.notice li {
  margin-bottom: 10px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.feature-card {
  padding: 24px;
}

.feature-card p,
.faq-item p,
.step-item p,
.notice {
  color: var(--text-soft);
}

.steps {
  display: grid;
  gap: 18px;
}

.step-item {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  padding: 22px 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

.step-index {
  width: 42px;
  height: 42px;
  flex: 0 0 42px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--primary);
  color: #111;
  font-weight: 800;
}

.notice {
  margin-top: 28px;
  padding: 24px 26px;
  border-left: 5px solid #60a5fa;
  border-top-left-radius: 0;
  border-bottom-left-radius: 0;
  background: #eff6ff;
}

.faq-list {
  display: grid;
  gap: 18px;
}

.faq-item {
  padding: 24px;
}

.stats {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: 8px;
}

.stat-item {
  padding: 18px;
}

.stat-item strong {
  display: block;
  margin-bottom: 8px;
  color: var(--primary);
  font-size: clamp(2rem, 4vw, 3rem);
}

.stat-item span {
  color: rgba(248, 250, 252, 0.82);
}

.site-footer {
  padding: 24px 0 36px;
  text-align: center;
  color: #64748b;
  background: #f8fafc;
  border-top: 1px solid #e2e8f0;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 960px) {
  .header-inner {
    flex-wrap: wrap;
    padding: 12px 0;
  }

  .site-nav {
    order: 3;
    width: 100%;
    justify-content: center;
    flex-wrap: wrap;
    gap: 14px;
  }

  .two-column,
  .feature-grid,
  .stats {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .hero-inner {
    padding: 72px 0 64px;
  }

  .section {
    padding: 56px 0;
  }

  .button,
  .header-download {
    width: 100%;
  }

  .header-download {
    justify-content: center;
  }

  .step-item {
    padding: 20px;
  }
}