:root {
  --primary: #0c8de9;
  --primary-dark: #0159a1;
  --accent: #f59e0b;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --text: #1e293b;
  --text-light: #64748b;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: 'IBM Plex Sans Thai', 'Inter', system-ui, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* Navigation */
.nav { background: white; border-bottom: 1px solid #e5e7eb; position: sticky; top: 0; z-index: 100; }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.nav-brand { font-weight: 700; font-size: 1.25rem; color: var(--primary); }
.nav-links { display: flex; gap: 32px; list-style: none; }
.nav-links a { color: var(--text-light); font-size: 0.875rem; font-weight: 500; transition: color 0.2s; }
.nav-links a:hover, .nav-links a.active { color: var(--primary); text-decoration: none; }

/* Hero */
.hero { background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: white; padding: 80px 0; text-align: center; }
.hero h1 { font-size: 2.5rem; font-weight: 700; margin-bottom: 16px; }
.hero p { font-size: 1.125rem; opacity: 0.9; max-width: 600px; margin: 0 auto; }

/* GIF Header — Mobile Banner */
.gif-header { width: 100%; overflow: hidden; }
.gif-header a { display: block; width: 100%; }
.gif-header a:hover { text-decoration: none; }
.gif-header img { width: 100%; display: block; }

/* Sections */
.section { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: 1.75rem; font-weight: 700; text-align: center; margin-bottom: 12px; }
.section-subtitle { text-align: center; color: var(--text-light); margin-bottom: 48px; }

/* Cards */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 24px; }
.card { background: white; border-radius: 16px; padding: 32px; border: 1px solid #e5e7eb; transition: box-shadow 0.3s; }
.card:hover { box-shadow: 0 8px 30px rgba(0,0,0,0.08); }
.card h3 { font-size: 1.125rem; font-weight: 600; margin-bottom: 8px; }
.card p { color: var(--text-light); font-size: 0.875rem; }

/* Benefits list */
.benefits { list-style: none; margin-top: 12px; }
.benefits li { padding: 4px 0; font-size: 0.875rem; color: var(--text-light); }
.benefits li::before { content: "✓ "; color: var(--primary); font-weight: 700; }

/* Footer */
.footer { background: #1e293b; color: #94a3b8; padding: 48px 0 24px; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 32px; margin-bottom: 32px; }
.footer h4 { color: white; font-size: 0.875rem; font-weight: 600; margin-bottom: 16px; }
.footer p, .footer a { font-size: 0.8125rem; color: #94a3b8; }
.footer-bottom { border-top: 1px solid #334155; padding-top: 24px; text-align: center; font-size: 0.75rem; }

/* Form */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 0.875rem; font-weight: 500; margin-bottom: 6px; }
.form-group input, .form-group textarea, .form-group select {
  width: 100%; padding: 12px 16px; border: 1px solid #d1d5db; border-radius: 12px;
  font-size: 0.875rem; font-family: inherit; transition: border-color 0.2s;
}
.form-group input:focus, .form-group textarea:focus {
  outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(12,141,233,0.1);
}
.btn-primary {
  display: inline-block; padding: 12px 32px; background: var(--primary); color: white;
  border: none; border-radius: 12px; font-size: 0.875rem; font-weight: 600;
  cursor: pointer; transition: background 0.2s;
}
.btn-primary:hover { background: var(--primary-dark); text-decoration: none; }

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.75rem; }
  .hero { padding: 48px 0; }
  .nav-links { display: none; }
  .section { padding: 40px 0; }
}