/* === Reset & Base === */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-bg: #faf8f5;
  --color-bg-alt: #f0ece6;
  --color-surface: #ffffff;
  --color-text: #1a1a1a;
  --color-text-secondary: #5c5c5c;
  --color-text-muted: #8a8a8a;
  --color-primary: #b8572a;
  --color-primary-hover: #9e4a24;
  --color-primary-light: #f5ebe4;
  --color-accent: #2a7ab8;
  --color-accent-hover: #24689e;
  --color-border: #e0dbd4;
  --color-code-bg: #1e1e2e;
  --color-code-text: #cdd6f4;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 2px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.08);
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;
  --max-width: 1120px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--color-primary-hover);
}

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

/* === Layout === */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

section {
  padding: 80px 0;
}

/* === Navigation === */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 248, 245, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.nav-brand span {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--color-text);
}

.lang-btn {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all 0.2s;
  font-family: var(--font-sans);
}

.lang-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* === Hero === */
.hero {
  padding: 120px 0 100px;
  text-align: center;
  background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-alt) 100%);
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
  color: var(--color-text);
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--color-primary), #d4845a);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 640px;
  margin: 0 auto 40px;
  line-height: 1.8;
}

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

/* === Buttons === */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all 0.2s;
  text-decoration: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(184, 87, 42, 0.3);
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--color-text-muted);
  color: var(--color-text);
  transform: translateY(-1px);
}

.btn svg {
  width: 20px;
  height: 20px;
}

/* === Section Headers === */
.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-header h2 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.section-header p {
  color: var(--color-text-secondary);
  font-size: 1.05rem;
  max-width: 560px;
  margin: 0 auto;
}

/* === Features === */
.features {
  background: var(--color-bg);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px;
  transition: all 0.3s;
}

.feature-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: var(--color-primary-light);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--color-primary);
}

.feature-icon svg {
  width: 24px;
  height: 24px;
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

/* === Download === */
.download {
  background: var(--color-bg-alt);
}

.download-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-bottom: 24px;
}

.download-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
  transition: all 0.3s;
}

.download-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.download-card.recommended {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 1px var(--color-primary);
}

.download-card.recommended .download-badge {
  display: inline-block;
}

.download-badge {
  display: none;
  padding: 4px 12px;
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.download-platform-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  color: var(--color-text-secondary);
}

.download-platform-icon svg {
  width: 100%;
  height: 100%;
}

.download-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.download-card .arch {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  margin-bottom: 16px;
}

.download-card .btn {
  width: 100%;
  justify-content: center;
}

.download-card .btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.download-meta {
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.download-meta a {
  color: var(--color-text-secondary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.download-error {
  display: none;
  text-align: center;
  padding: 12px 20px;
  background: #fef2f2;
  color: #b91c1c;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  margin-bottom: 16px;
}

/* === Quick Start === */
.quickstart {
  background: var(--color-bg);
}

.quickstart-steps {
  max-width: 680px;
  margin: 0 auto;
}

.quickstart-step {
  margin-bottom: 32px;
}

.quickstart-step h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.quickstart-step h3 .step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  background: var(--color-primary);
  color: #fff;
  border-radius: 50%;
  font-size: 0.8rem;
  font-weight: 700;
  flex-shrink: 0;
}

.quickstart-step p {
  color: var(--color-text-secondary);
  margin-bottom: 12px;
  padding-left: 38px;
}

.code-block {
  background: var(--color-code-bg);
  color: var(--color-code-text);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.6;
  overflow-x: auto;
  margin-left: 38px;
}

.code-block code {
  font-family: inherit;
}

/* === Footer === */
.footer {
  padding: 40px 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer p {
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.footer-links {
  display: flex;
  gap: 24px;
  list-style: none;
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.footer-links a:hover {
  color: var(--color-text-secondary);
}

/* === Responsive === */
@media (max-width: 768px) {
  section {
    padding: 60px 0;
  }

  .hero {
    padding: 80px 0 60px;
  }

  .nav-links {
    gap: 20px;
  }

  .features-grid,
  .download-cards {
    grid-template-columns: 1fr;
  }

  .footer-content {
    flex-direction: column;
    text-align: center;
  }

  .quickstart-step p,
  .code-block {
    padding-left: 0;
    margin-left: 0;
  }
}

@media (max-width: 480px) {
  .nav-links {
    display: none;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn {
    justify-content: center;
  }
}