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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: #111111;
  background: #f7f7f7;
  line-height: 1.6;
}

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

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(247, 247, 247, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #e2e2e2;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
}

.logo {
  font-weight: 600;
  letter-spacing: 0.06em;
}

.nav-links {
  display: flex;
  gap: 20px;
  font-size: 14px;
}

.hero {
  padding: 96px 0 72px;
  text-align: center;
}

.hero h1 {
  font-size: clamp(32px, 4vw, 56px);
  margin: 0 0 16px;
}

.hero p {
  font-size: 18px;
  color: #444444;
  max-width: 640px;
  margin: 0 auto 32px;
}

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

.hero-preview {
  margin: 32px auto 0;
  max-width: 640px;
  border-radius: 24px;
  overflow: hidden;
  border: 1px solid #e6e6e6;
  background: #ffffff;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.08);
}

.hero-preview img {
  display: block;
  width: 100%;
  height: auto;
}

.button {
  padding: 12px 24px;
  border-radius: 999px;
  border: 1px solid #111111;
  font-size: 14px;
  font-weight: 500;
  background: #111111;
  color: #ffffff;
}

.button.secondary {
  background: transparent;
  color: #111111;
}

.section {
  padding: 72px 0;
  background: #ffffff;
  border-top: 1px solid #ececec;
}

.section h2 {
  font-size: 28px;
  margin-bottom: 16px;
}

.section p {
  color: #444444;
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  margin-top: 32px;
}

.tutorial-list {
  display: grid;
  gap: 16px;
  margin-top: 24px;
}

.tutorial-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 20px;
  border-radius: 14px;
  border: 1px solid #e6e6e6;
  background: #fafafa;
  font-weight: 500;
}

.tutorial-item span {
  font-size: 13px;
  color: #666666;
  font-weight: 400;
}

.card {
  padding: 24px;
  border: 1px solid #ececec;
  border-radius: 16px;
  background: #fafafa;
}

.card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.card p {
  margin: 0;
  color: #555555;
  font-size: 14px;
}

.cta {
  text-align: center;
}

footer {
  padding: 32px 0 48px;
  font-size: 13px;
  color: #666666;
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.legal {
  max-width: 760px;
  margin: 0 auto;
  padding: 72px 0;
}

.markdown-content {
  background: #ffffff;
  border: 1px solid #ececec;
  border-radius: 16px;
  padding: 24px;
  margin-top: 24px;
}

.markdown-content h1,
.markdown-content h2,
.markdown-content h3 {
  margin-top: 24px;
}

.markdown-content img {
  display: block;
  width: auto;
  max-width: min(520px, 100%);
  height: auto;
  border-radius: 12px;
  border: 1px solid #ededed;
  margin: 12px 0;
}

.markdown-content pre {
  background: #111111;
  color: #ffffff;
  padding: 16px;
  border-radius: 12px;
  overflow-x: auto;
}

.markdown-content code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 13px;
}

.legal h1 {
  font-size: 32px;
  margin-bottom: 8px;
}

.legal h2 {
  font-size: 20px;
  margin-top: 32px;
}

.legal p,
.legal li {
  color: #444444;
  font-size: 15px;
}

.legal ul {
  padding-left: 20px;
}

.subtle {
  color: #666666;
  font-size: 13px;
}

@media (max-width: 640px) {
  .container {
    padding: 0 16px;
  }

  .nav {
    flex-direction: column;
    gap: 12px;
  }

  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px 16px;
  }

  .hero {
    padding: 72px 0 56px;
  }

  .hero p {
    font-size: 16px;
    margin-bottom: 24px;
  }

  .section {
    padding: 56px 0;
  }

  .section h2 {
    font-size: 24px;
  }

  .features {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .tutorial-item {
    padding: 14px 16px;
  }

  .legal {
    padding: 56px 0;
  }

  .markdown-content {
    padding: 18px;
  }

  .hero-actions {
    flex-direction: column;
  }

  .markdown-content img {
    max-width: 100%;
  }
}