/* ============================================
   硅基网格 Silicon Grid — 全局样式
   品牌色: #00d4aa (青绿) → #6c5ce7 (紫)
   背景: #0a0a0f (深黑)
   ============================================ */

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

:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: #1a1a26;
  --bg-card-hover: #222230;
  --text-primary: #e8e8f0;
  --text-secondary: #9898a8;
  --text-muted: #6a6a7a;
  --accent-green: #00d4aa;
  --accent-purple: #6c5ce7;
  --gradient-brand: linear-gradient(135deg, #00d4aa, #6c5ce7);
  --gradient-brand-h: linear-gradient(90deg, #00d4aa, #6c5ce7);
  --border: rgba(255,255,255,0.06);
  --border-light: rgba(255,255,255,0.1);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-xs: 4px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --transition: 0.25s ease;
  --max-width: 1200px;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-green); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--accent-purple); }
img { max-width: 100%; height: auto; display: block; }

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

/* --- Typography --- */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.3; letter-spacing: 0.02em; }
h1 { font-size: clamp(2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.2rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.4rem); }

.gradient-text {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-title {
  text-align: center;
  margin-bottom: 48px;
}
.section-title h2 { margin-bottom: 8px; }
.section-title p { color: var(--text-secondary); font-size: 1rem; }

/* --- Navbar --- */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(10,10,15,0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  transition: background 0.3s;
}
.navbar .container {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-logo img { height: 36px; }
.nav-logo span {
  font-size: 1.15rem; font-weight: 700;
  background: var(--gradient-brand-h);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.nav-links { display: flex; gap: 32px; list-style: none; }
.nav-links a {
  color: var(--text-secondary); font-size: 0.9rem; font-weight: 500;
  position: relative; padding: 4px 0;
}
.nav-links a::after {
  content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px;
  background: var(--gradient-brand-h); transition: width 0.3s;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }
.nav-links a.active { color: var(--accent-green); }
.nav-links a.active::after { width: 100%; }

.menu-toggle {
  display: none; background: none; border: none; cursor: pointer; padding: 8px;
}
.menu-toggle span {
  display: block; width: 24px; height: 2px; margin: 5px 0;
  background: var(--text-primary); transition: var(--transition);
}

/* --- Hero --- */
.hero {
  min-height: 100vh; display: flex; align-items: center;
  padding: 100px 0 80px; position: relative; overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
  background: radial-gradient(ellipse at 30% 50%, rgba(0,212,170,0.08) 0%, transparent 60%),
              radial-gradient(ellipse at 70% 50%, rgba(108,92,231,0.08) 0%, transparent 60%);
  pointer-events: none;
}
.hero .container {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center;
}
.hero-content h1 { margin-bottom: 16px; }
.hero-content .tagline {
  font-size: 1.25rem; color: var(--text-secondary); margin-bottom: 32px;
}
.hero-buttons { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-graphic {
  display: flex; justify-content: center; align-items: center;
}
.hero-graphic img { max-width: 300px; opacity: 0.9; }
.hero-graphic .glow-ring {
  position: absolute; width: 320px; height: 320px; border-radius: 50%;
  background: conic-gradient(from 0deg, transparent, var(--accent-green), var(--accent-purple), transparent);
  opacity: 0.15; filter: blur(60px); animation: spin 20s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* --- Buttons --- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: var(--radius-sm); font-size: 0.95rem;
  font-weight: 600; cursor: pointer; border: none; transition: var(--transition);
  text-decoration: none; white-space: nowrap;
}
.btn-primary {
  background: var(--gradient-brand-h); color: #fff;
  box-shadow: 0 4px 20px rgba(0,212,170,0.25);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 28px rgba(0,212,170,0.35); color: #fff; }
.btn-outline {
  background: transparent; color: var(--text-primary);
  border: 1px solid var(--border-light);
}
.btn-outline:hover { border-color: var(--accent-green); color: var(--accent-green); background: rgba(0,212,170,0.05); }
.btn-lg { padding: 16px 36px; font-size: 1.05rem; }

/* --- Sections --- */
.section { padding: 100px 0; }
.section-dark { background: var(--bg-secondary); }

/* --- Feature Cards --- */
.features-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px;
}
.feature-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 32px;
  border: 1px solid var(--border); transition: var(--transition);
}
.feature-card:hover { background: var(--bg-card-hover); border-color: var(--border-light); transform: translateY(-4px); }
.feature-icon {
  width: 52px; height: 52px; border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center; margin-bottom: 20px;
  font-size: 1.5rem;
}
.feature-icon.green { background: rgba(0,212,170,0.12); color: var(--accent-green); }
.feature-icon.purple { background: rgba(108,92,231,0.12); color: var(--accent-purple); }
.feature-card h3 { margin-bottom: 8px; }
.feature-card p { color: var(--text-secondary); font-size: 0.95rem; }

/* --- Team Cards --- */
.team-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 28px;
}
.team-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 28px;
  text-align: center; border: 1px solid var(--border); transition: var(--transition);
}
.team-card:hover { transform: translateY(-4px); border-color: var(--border-light); }
.team-avatar {
  width: 80px; height: 80px; border-radius: 50%; margin: 0 auto 16px;
  background: var(--gradient-brand); display: flex; align-items: center;
  justify-content: center; font-size: 1.8rem; font-weight: 700; color: #fff;
  overflow: hidden;
}
.team-avatar img {
  width: 100%; height: 100%; object-fit: cover;
}
.team-card h3 { margin-bottom: 4px; }
.team-role { color: var(--accent-green); font-size: 0.85rem; margin-bottom: 8px; }
.team-bio { color: var(--text-secondary); font-size: 0.88rem; }

/* --- Download Cards --- */
.download-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 24px;
}
.download-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 32px;
  border: 1px solid var(--border); transition: var(--transition);
  display: flex; flex-direction: column;
}
.download-card:hover { border-color: var(--accent-green); }
.download-card.featured { border-color: var(--accent-green); background: rgba(0,212,170,0.03); }
.download-platform { font-size: 0.85rem; color: var(--accent-purple); font-weight: 600; margin-bottom: 8px; }
.download-card h3 { margin-bottom: 4px; }
.download-version { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 12px; }
.download-size { color: var(--text-secondary); font-size: 0.85rem; margin-bottom: 16px; }
.download-features { list-style: none; margin-bottom: 20px; flex: 1; }
.download-features li { color: var(--text-secondary); font-size: 0.88rem; padding: 4px 0; padding-left: 20px; position: relative; }
.download-features li::before {
  content: '✓'; position: absolute; left: 0; color: var(--accent-green); font-size: 0.75rem;
}

/* --- Principles / Timeline --- */
.principle-list { display: flex; flex-direction: column; gap: 32px; }
.principle-item {
  display: grid; grid-template-columns: 60px 1fr; gap: 24px;
  padding: 24px; background: var(--bg-card); border-radius: var(--radius);
  border: 1px solid var(--border);
}
.principle-num {
  width: 56px; height: 56px; border-radius: var(--radius-sm);
  background: var(--gradient-brand); display: flex; align-items: center;
  justify-content: center; font-size: 1.4rem; font-weight: 700; color: #fff;
}
.principle-content h3 { margin-bottom: 8px; }
.principle-content p { color: var(--text-secondary); }

/* --- Page Header --- */
.page-header {
  padding: 120px 0 60px; text-align: center; position: relative; overflow: hidden;
}
.page-header::before {
  content: ''; position: absolute; top: 0; left: 50%; transform: translateX(-50%);
  width: 600px; height: 400px;
  background: radial-gradient(ellipse, rgba(0,212,170,0.06) 0%, transparent 70%);
  pointer-events: none;
}
.page-header .subtitle { color: var(--text-secondary); margin-top: 12px; font-size: 1.1rem; }

/* --- Footer --- */
.footer {
  background: var(--bg-secondary); border-top: 1px solid var(--border);
  padding: 48px 0 24px;
}
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 32px;
}
.footer-brand img { height: 32px; margin-bottom: 12px; }
.footer-brand p { color: var(--text-muted); font-size: 0.9rem; }
.footer-col h4 { font-size: 0.9rem; color: var(--text-primary); margin-bottom: 16px; text-transform: uppercase; letter-spacing: 0.1em; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 8px; }
.footer-col a { color: var(--text-muted); font-size: 0.88rem; }
.footer-col a:hover { color: var(--accent-green); }
.footer-bottom {
  border-top: 1px solid var(--border); padding-top: 24px;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
  color: var(--text-muted); font-size: 0.82rem;
}

/* --- Utilities --- */
.text-center { text-align: center; }
.mt-2 { margin-top: 8px; }
.mt-4 { margin-top: 16px; }
.mt-8 { margin-top: 32px; }
.mb-8 { margin-bottom: 32px; }

/* --- Page-specific hero - inner pages --- */
.inner-hero {
  padding: 140px 0 80px; text-align: center;
  position: relative; overflow: hidden;
}
.inner-hero::before {
  content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
  background: radial-gradient(ellipse at 50% 30%, rgba(0,212,170,0.06) 0%, transparent 60%);
  pointer-events: none;
}

/* --- Technology stack card --- */
.tech-stack {
  display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 24px;
}
.tech-tag {
  padding: 6px 16px; background: var(--bg-card); border: 1px solid var(--border);
  border-radius: 20px; font-size: 0.82rem; color: var(--text-secondary);
}
.tech-tag:hover { border-color: var(--accent-green); color: var(--accent-green); }

/* --- Image lightbox trigger --- */
img.clickable { cursor: pointer; transition: transform 0.2s; }
img.clickable:hover { transform: scale(1.02); }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .hero .container { grid-template-columns: 1fr; text-align: center; }
  .hero-graphic { order: -1; }
  .hero-graphic img { max-width: 200px; }
  .hero-buttons { justify-content: center; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed; top: 64px; left: 0; right: 0;
    background: rgba(10,10,15,0.97); flex-direction: column;
    padding: 24px; gap: 16px; display: none;
    border-bottom: 1px solid var(--border);
  }
  .nav-links.open { display: flex; }
  .menu-toggle { display: block; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .principle-item { grid-template-columns: 1fr; }
  .principle-num { margin: 0 auto; }
  .section { padding: 60px 0; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero { padding: 80px 0 60px; }
  .hero-buttons { flex-direction: column; }
  .download-grid { grid-template-columns: 1fr; }
}