*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0d1117;
  --surface: #161b22;
  --border: #30363d;
  --text: #c9d1d9;
  --text-muted: #8b949e;
  --accent: #58a6ff;
  --accent2: #f78166;
  --green: #3fb950;
  --radius: 12px;
  --radius-sm: 8px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }

nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(13,17,23,0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 960px; margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between;
  height: 56px;
}
.logo {
  font-weight: 700; font-size: 20px; color: var(--text); text-decoration: none;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
nav ul { display: flex; gap: 24px; list-style: none; }
nav ul a { color: var(--text-muted); text-decoration: none; font-size: 14px; font-weight: 500; transition: color .15s; }
nav ul a:hover { color: var(--text); }

.hero {
  padding: 100px 0 80px; text-align: center;
}
.hero-badge {
  display: inline-block; padding: 4px 16px; border-radius: 20px;
  background: rgba(88,166,255,0.1); color: var(--accent);
  font-size: 13px; font-weight: 600; letter-spacing: 0.5px;
  margin-bottom: 24px;
}
.hero h1 { font-size: 52px; font-weight: 700; margin-bottom: 16px; letter-spacing: -1px; }
.gradient-text { background: linear-gradient(135deg, var(--accent), var(--accent2)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero-subtitle { font-size: 18px; color: var(--text-muted); max-width: 520px; margin: 0 auto 32px; }
.hero-links { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 24px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 600; text-decoration: none;
  cursor: pointer; border: none; transition: all .15s;
}
.btn-primary {
  background: #238636; color: #fff; border: 1px solid rgba(240,246,252,0.1);
}
.btn-primary:hover { background: #2ea043; }

.github-section { padding: 60px 0; }
.github-section h2, .contact-section h2 { font-size: 32px; font-weight: 700; margin-bottom: 8px; letter-spacing: -0.5px; }
.section-desc { color: var(--text-muted); margin-bottom: 40px; }

.github-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; margin-bottom: 60px; }

.repo-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px;
  transition: border-color .15s;
}
.repo-card:hover { border-color: var(--accent); }
.repo-card h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.repo-card h3 a { color: var(--accent); text-decoration: none; }
.repo-card h3 a:hover { text-decoration: underline; }
.repo-card p { font-size: 13px; color: var(--text-muted); margin-bottom: 12px; line-height: 1.5; }
.repo-meta { display: flex; gap: 16px; font-size: 12px; color: var(--text-muted); align-items: center; }
.repo-meta .lang-dot { width: 10px; height: 10px; border-radius: 50%; display: inline-block; }
.repo-meta .stars { display: flex; align-items: center; gap: 4px; }
.repo-error { grid-column: 1/-1; color: var(--text-muted); text-align: center; padding: 40px; }

.skeleton { animation: pulse 1.5s infinite; }
.skeleton-line { height: 14px; background: var(--border); border-radius: 4px; margin-bottom: 10px; }
.skeleton-title { width: 60%; }
.skeleton-desc { width: 90%; }
.skeleton-meta { width: 40%; }
@keyframes pulse { 0%,100% { opacity:1; } 50% { opacity:0.5; } }

.github-guide h3 { font-size: 22px; font-weight: 600; margin-bottom: 20px; }
.guide-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; }
.guide-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px;
}
.guide-icon { font-size: 28px; margin-bottom: 12px; }
.guide-card h4 { font-size: 15px; font-weight: 600; margin-bottom: 8px; }
.guide-card p { font-size: 13px; color: var(--text-muted); line-height: 1.5; }

.contact-section { padding: 60px 0 100px; }
.contact-form { max-width: 560px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 6px; color: var(--text); }
.form-group input, .form-group textarea {
  width: 100%; padding: 10px 14px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text); font-size: 14px; font-family: inherit;
  transition: border-color .15s;
}
.form-group input:focus, .form-group textarea:focus {
  outline: none; border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(88,166,255,0.15);
}
.form-group textarea { resize: vertical; }

.btn-submit {
  width: 100%; padding: 12px 24px; font-size: 15px;
  justify-content: center;
}
.btn-submit:disabled { opacity: 0.6; cursor: not-allowed; }
.btn-spinner.hidden, .btn-text.hidden { display: none; }

.form-status {
  padding: 12px 16px; border-radius: var(--radius-sm); margin-bottom: 16px;
  font-size: 13px; font-weight: 500;
}
.form-status.success { background: rgba(63,185,80,0.15); color: var(--green); border: 1px solid rgba(63,185,80,0.3); }
.form-status.error { background: rgba(248,81,73,0.15); color: #f85149; border: 1px solid rgba(248,81,73,0.3); }
.form-status.hidden { display: none; }

footer { padding: 32px 0; border-top: 1px solid var(--border); text-align: center; }
footer p { font-size: 13px; color: var(--text-muted); }

@media (max-width: 640px) {
  .hero h1 { font-size: 34px; }
  .hero-subtitle { font-size: 15px; }
  .hero { padding: 60px 0 50px; }
  .github-grid { grid-template-columns: 1fr; }
  .guide-cards { grid-template-columns: 1fr; }
}