/* ==========================================================================
   CLC Book Store — Public Website & Landing Page CSS
   Clean, modern, commercial UI with local assets and zero external dependencies
   ========================================================================== */

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --dark: #0f172a;
  --dark-surface: #1e293b;
  --text: #334155;
  --text-muted: #64748b;
  --bg-page: #f8fafc;
  --card-bg: #ffffff;
  --border: #e2e8f0;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.08), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.04);
  --font: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Myanmar Text", sans-serif;
}

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

body {
  font-family: var(--font);
  background-color: var(--bg-page);
  color: var(--text);
  line-height: 1.6;
  font-size: 15px;
}

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

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header & Navbar */
.site-header {
  background: white;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 800;
  color: var(--dark);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  font-weight: 500;
  color: var(--text);
  transition: color 0.15s ease;
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background: white;
  border-color: var(--border);
  color: var(--dark);
}

.btn-secondary:hover {
  background: #f1f5f9;
}

.btn-telegram {
  background: #229ed9;
  color: white;
  box-shadow: 0 4px 12px rgba(34, 158, 217, 0.3);
}

.btn-telegram:hover {
  background: #1b87ba;
  transform: translateY(-1px);
}

/* Hero Section */
.hero {
  padding: 70px 0 60px;
  background: linear-gradient(180deg, #eff6ff 0%, var(--bg-page) 100%);
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  background: white;
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-full);
  font-size: 13px;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}

.hero-title {
  font-size: 38px;
  font-weight: 800;
  color: var(--dark);
  line-height: 1.3;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto 32px;
}

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

/* Features / Steps */
.steps-section {
  padding: 60px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 40px;
}

.section-title {
  font-size: 26px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 8px;
}

.section-subtitle {
  font-size: 14px;
  color: var(--text-muted);
}

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

.step-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px 24px;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.step-icon {
  width: 60px;
  height: 60px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  margin: 0 auto 16px;
}

.step-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 8px;
}

.step-desc {
  font-size: 13px;
  color: var(--text-muted);
}

/* Books Grid */
.books-section {
  padding: 60px 0;
  background: white;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.books-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}

.book-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.book-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.book-cover {
  height: 240px;
  background: #f1f5f9;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.book-info {
  padding: 16px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.book-category {
  font-size: 11px;
  font-weight: 600;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.book-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
  line-height: 1.4;
}

.book-author {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.book-prices {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* Footer */
.site-footer {
  background: var(--dark);
  color: #94a3b8;
  padding: 50px 0 24px;
  font-size: 13px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand h4 {
  color: white;
  font-size: 18px;
  margin-bottom: 12px;
}

.footer-title {
  color: white;
  font-weight: 600;
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 8px;
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.08);
}

@media (max-width: 768px) {
  .hero-title { font-size: 28px; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .nav-links { display: none; }
}