/**
 * ZERTUCHA EĞİTİM PLATFORMU - MODERN iOS / APPLE ESİNTİLİ TASARIM SİSTEMİ
 * Saf Vanilla CSS - Sıfır Dış Bağımlılık - PageSpeed 100 Uyumlu
 */

:root {
  /* Renk Paleti */
  --bg-body: #0a0e17;
  --bg-surface: #111827;
  --bg-card: rgba(17, 24, 39, 0.75);
  --bg-card-hover: rgba(31, 41, 55, 0.85);
  --bg-glass: rgba(17, 24, 39, 0.72);
  --bg-glass-elevated: rgba(30, 41, 59, 0.85);
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  --primary: #0066ff;
  --primary-hover: #0052cc;
  --primary-glow: rgba(0, 102, 255, 0.25);
  
  --accent-indigo: #6366f1;
  --accent-purple: #a855f7;
  
  --whatsapp: #25d366;
  --whatsapp-hover: #20bd5a;
  --whatsapp-glow: rgba(37, 211, 102, 0.3);
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(0, 102, 255, 0.5);
  --border-card: rgba(255, 255, 255, 0.1);
  
  /* Tipografi - Yerel Sistem Fontları (0ms Gecikme) */
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  
  /* Gölgeler & Derinlik */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.5);
  --shadow-glass: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  
  /* Kavisler (iOS Corner Radius) */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;
  
  /* Geçişler */
  --transition: all 0.22s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  
  --container-max: 1240px;
}

/* 1. RESET & TEMEL TANIMLAR */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.6;
  font-size: 16px;
  overflow-x: hidden;
  position: relative;
  background-image: 
    radial-gradient(circle at 15% 10%, rgba(0, 102, 255, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 85% 25%, rgba(99, 102, 241, 0.06) 0%, transparent 40%),
    radial-gradient(circle at 50% 70%, rgba(37, 211, 102, 0.04) 0%, transparent 50%);
  background-attachment: fixed;
}

img, video {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  transition: var(--transition);
}

/* 2. DÜZEN & KONTEYNER */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.section {
  padding-top: 96px;
  padding-bottom: 96px;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 56px auto;
}

.section-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(0, 102, 255, 0.12);
  border: 1px solid rgba(0, 102, 255, 0.3);
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 600;
  color: #38bdf8;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(28px, 3.5vw, 42px);
  font-weight: 700;
  line-height: 1.2;
  color: #ffffff;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section-description {
  font-size: 17px;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 3. BUTONLAR & ETİKETLER */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 24px;
  border-radius: var(--radius-full);
  font-size: 15px;
  font-weight: 600;
  line-height: 1;
  white-space: nowrap;
  transition: var(--transition);
  user-select: none;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 14px var(--primary-glow);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 102, 255, 0.4);
}

.btn-whatsapp {
  background: var(--whatsapp);
  color: #052e16;
  font-weight: 700;
  box-shadow: 0 4px 14px var(--whatsapp-glow);
}

.btn-whatsapp:hover {
  background: var(--whatsapp-hover);
  color: #022c22;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 211, 102, 0.45);
}

.btn-glass {
  background: rgba(255, 255, 255, 0.07);
  color: #ffffff;
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.btn-glass:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 9px 18px;
  font-size: 14px;
}

.btn-lg {
  padding: 16px 32px;
  font-size: 16px;
}

.btn-block {
  width: 100%;
}

/* Seviye Etiketleri */
.badge-level {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.badge-level-beginner {
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.badge-level-intermediate {
  background: rgba(245, 158, 11, 0.15);
  color: #fbbf24;
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.badge-level-advanced {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.badge-level-all {
  background: rgba(99, 102, 241, 0.15);
  color: #818cf8;
  border: 1px solid rgba(99, 102, 241, 0.3);
}

/* 4. NAVBAR & BAŞLIK ALANI */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 20px;
  letter-spacing: -0.02em;
  color: #ffffff;
}

.brand-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary), var(--accent-indigo));
  padding: 4px 8px;
  border-radius: 6px;
  font-size: 11px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

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

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-muted);
  position: relative;
  padding: 6px 0;
}

.nav-link:hover,
.nav-link.active {
  color: #ffffff;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: var(--transition);
  border-radius: 2px;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.btn-mobile-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: #fff;
  align-items: center;
  justify-content: center;
}

/* Mobil Menü Çekmecesi */
.mobile-nav-drawer {
  position: fixed;
  top: 76px;
  left: 0;
  width: 100%;
  height: calc(100vh - 76px);
  background: rgba(10, 14, 23, 0.98);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  transform: translateY(-100%);
  opacity: 0;
  pointer-events: none;
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.3s ease;
  z-index: 999;
}

.mobile-nav-drawer.active {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav-link {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-muted);
  display: block;
  padding: 8px 0;
  border-bottom: 1px solid var(--border-subtle);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  color: #ffffff;
}

/* 5. HERO ALANI */
.hero-section {
  padding-top: 80px;
  padding-bottom: 100px;
  position: relative;
  overflow: hidden;
  text-align: center;
}

.hero-content {
  max-width: 860px;
  margin: 0 auto;
}

.hero-badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  color: #e2e8f0;
  margin-bottom: 24px;
  backdrop-filter: blur(10px);
}

.hero-badge-pill .pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--whatsapp);
  box-shadow: 0 0 10px var(--whatsapp);
}

.hero-title {
  font-size: clamp(34px, 5.5vw, 62px);
  font-weight: 800;
  line-height: 1.15;
  color: #ffffff;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero-title-highlight {
  background: linear-gradient(135deg, #60a5fa 0%, #a78bfa 50%, #f472b6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: clamp(17px, 2vw, 20px);
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 40px auto;
  line-height: 1.6;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

/* Hero Güven Kartları */
.hero-trust-bar {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
  padding-top: 40px;
  border-top: 1px solid var(--border-subtle);
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 12px;
  text-align: left;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-subtle);
  padding: 16px 20px;
  border-radius: var(--radius-md);
}

.trust-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(0, 102, 255, 0.12);
  color: #60a5fa;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.trust-text h4 {
  font-size: 15px;
  font-weight: 600;
  color: #fff;
}

.trust-text p {
  font-size: 13px;
  color: var(--text-dim);
}

/* 6. KATEGORİLER IZGARASI */
.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}

.category-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  position: relative;
  transition: var(--transition);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.category-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(0, 102, 255, 0.4);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.category-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: #38bdf8;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.category-card:hover .category-icon {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.category-title {
  font-size: 17px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.3;
}

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

.category-count {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-dim);
  margin-top: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* 7. EĞİTİM KARTLARI */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 28px;
}

.course-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition-smooth);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--shadow-sm);
}

.course-card:hover {
  border-color: rgba(255, 255, 255, 0.25);
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.course-cover-wrap {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #0f172a;
}

.course-cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.course-card:hover .course-cover-img {
  transform: scale(1.05);
}

.course-cover-badges {
  position: absolute;
  top: 14px;
  left: 14px;
  right: 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 2;
}

.course-category-pill {
  padding: 4px 10px;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
  font-size: 11px;
  font-weight: 600;
  color: #e2e8f0;
}

.course-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.course-title {
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.35;
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.course-title a:hover {
  color: #60a5fa;
}

.course-excerpt {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px 0;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 20px;
  font-size: 13px;
  color: var(--text-dim);
}

.course-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.course-footer {
  margin-top: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.course-price-wrap {
  display: flex;
  flex-direction: column;
}

.course-price-label {
  font-size: 11px;
  color: var(--text-dim);
  text-transform: uppercase;
}

.course-price-val {
  font-size: 22px;
  font-weight: 800;
  color: #ffffff;
}

.course-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 8. EĞİTİM DETAY SAYFASI DÜZENİ */
.course-detail-header {
  padding-top: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(255, 255, 255, 0.015);
}

.breadcrumb-nav {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 20px;
}

.breadcrumb-nav a:hover {
  color: #ffffff;
}

.course-detail-grid {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 48px;
  align-items: start;
  padding-top: 48px;
}

.detail-main-content {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.content-block-title {
  font-size: 24px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.content-block-title::before {
  content: '';
  width: 4px;
  height: 22px;
  background: var(--primary);
  border-radius: 4px;
}

.detail-typography {
  font-size: 16px;
  color: #cbd5e1;
  line-height: 1.8;
}

.detail-typography p {
  margin-bottom: 16px;
}

/* Kazanımlar Listesi */
.outcomes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
}

.outcome-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  padding: 14px 18px;
  border-radius: var(--radius-md);
  font-size: 14px;
  color: #e2e8f0;
}

.outcome-icon {
  color: #34d399;
  flex-shrink: 0;
  margin-top: 2px;
}

/* Müfredat Akordeonu */
.curriculum-accordion {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.section-item {
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-card);
}

.section-header-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  font-size: 16px;
  font-weight: 600;
  color: #ffffff;
  background: rgba(255, 255, 255, 0.02);
  text-align: left;
}

.section-header-btn:hover {
  background: rgba(255, 255, 255, 0.05);
}

.section-header-btn .accordion-icon {
  transition: transform 0.3s ease;
}

.section-item.open .section-header-btn .accordion-icon {
  transform: rotate(180deg);
}

.lessons-list {
  display: none;
  flex-direction: column;
  border-top: 1px solid var(--border-subtle);
  background: rgba(0, 0, 0, 0.2);
}

.section-item.open .lessons-list {
  display: flex;
}

.lesson-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 14px;
}

.lesson-item:last-child {
  border-bottom: none;
}

.lesson-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lesson-duration {
  font-size: 12px;
  color: var(--text-dim);
  padding: 3px 8px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-sm);
}

/* Sağ Yapışkan Satın Alma Kartı */
.detail-sidebar-card {
  position: sticky;
  top: 96px;
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

.sidebar-media-preview {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #000;
  overflow: hidden;
}

.sidebar-body {
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.sidebar-price-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
}

.guarantee-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 13px;
  color: var(--text-muted);
}

.guarantee-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 9. PORTFOLYO & SOSYAL MEDYA */
.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 28px;
}

.portfolio-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: var(--transition-smooth);
}

.portfolio-card:hover {
  transform: translateY(-5px);
  border-color: rgba(255, 255, 255, 0.2);
  box-shadow: var(--shadow-lg);
}

.portfolio-body {
  padding: 24px;
}

.social-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.social-card {
  display: flex;
  align-items: center;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  padding: 20px;
  border-radius: var(--radius-lg);
  transition: var(--transition);
}

.social-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--primary);
  transform: translateY(-3px);
}

.social-icon-wrap {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  flex-shrink: 0;
}

/* 10. SIKÇA SORULAN SORULAR */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.faq-question-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 600;
  color: #ffffff;
  text-align: left;
}

.faq-answer {
  display: none;
  padding: 0 24px 20px 24px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.7;
}

.faq-item.open .faq-answer {
  display: block;
}

.faq-item.open .accordion-icon {
  transform: rotate(180deg);
}

/* 11. DUYURU POPUP MODALI */
.popup-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.popup-backdrop.active {
  display: flex;
  opacity: 1;
}

.popup-modal {
  background: var(--bg-surface);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  max-width: 520px;
  width: 100%;
  padding: 36px 32px;
  position: relative;
  box-shadow: var(--shadow-lg);
  text-align: center;
  transform: scale(0.95);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.popup-backdrop.active .popup-modal {
  transform: scale(1);
}

.popup-close-btn {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
}

.popup-close-btn:hover {
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
}

/* 12. SABİT WHATSAPP YÜZEN BUTONU */
.floating-whatsapp {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 1000;
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--whatsapp);
  color: #042f1a;
  padding: 12px 20px 12px 16px;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 14px;
  box-shadow: 0 8px 24px rgba(37, 211, 102, 0.4);
  transition: var(--transition);
}

.floating-whatsapp:hover {
  background: var(--whatsapp-hover);
  transform: scale(1.05) translateY(-2px);
  box-shadow: 0 12px 30px rgba(37, 211, 102, 0.55);
}

/* 13. FOOTER */
.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: rgba(10, 14, 23, 0.9);
  padding: 64px 0 32px 0;
  margin-top: 64px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-col h4 {
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 20px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  font-size: 14px;
  color: var(--text-muted);
}

.footer-links a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-dim);
}

/* 14. 404 VE STATİK YASAL SAYFA */
.static-page-container {
  max-width: 800px;
  margin: 48px auto;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 48px;
}

.static-page-title {
  font-size: 32px;
  font-weight: 800;
  color: #fff;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.error-404-wrap {
  text-align: center;
  padding: 120px 24px;
}

.error-code {
  font-size: clamp(80px, 15vw, 140px);
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 16px;
}

/* 15. DUYARLILIK (RESPONSIVE BREAKPOINTS) */
@media (max-width: 1024px) {
  .course-detail-grid {
    grid-template-columns: 1fr;
  }
  .detail-sidebar-card {
    position: static;
    margin-top: 32px;
  }
  .hero-trust-bar {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-actions .btn-whatsapp {
    display: none;
  }
  .btn-mobile-toggle {
    display: flex;
  }
  .section {
    padding-top: 64px;
    padding-bottom: 64px;
  }
  .courses-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .floating-whatsapp span {
    display: none;
  }
  .floating-whatsapp {
    padding: 14px;
    bottom: 20px;
    right: 20px;
  }
  .static-page-container {
    padding: 24px;
  }
}