/* =========================================
   CSS DEĞİŞKENLERİ (TEMA RENKLERİ)
   ========================================= */
:root {
  /* GÜNDÜZ MODU: Gökyüzü ve Doğa Teması */
  --bg-color: #e0f7fa; /* Açık mavi gökyüzü */
  --text-color: #2c3e50;
  --card-bg: #ffffff;
  --card-border: #81d4fa;
  --card-shadow: 0 8px 16px rgba(0, 0, 0, 0.08);
  --primary-color: #4caf50; /* Doğa yeşili */
  --accent-color: #ff9800; /* Güneş turuncusu */
  --header-bg: linear-gradient(135deg, #4fc3f7, #29b6f6);
  --badge-bg: #fff9c4;
  --badge-text: #f57f17;
  /* Hafif bulutlu veya puantiyeli eğlenceli zemin */
  --bg-pattern: radial-gradient(circle, #ffffff 2px, transparent 2px);
  --bg-size: 30px 30px;
}

[data-theme="dark"] {
  /* GECE MODU: Uzay ve Galaksi Teması */
  --bg-color: #0b0c10; /* Derin uzay siyahı */
  --text-color: #f8fafc;
  --card-bg: #1f2833;
  --card-border: #45a29e;
  --card-shadow: 0 8px 20px rgba(102, 252, 241, 0.15);
  --primary-color: #66fcf1; /* Neon galaksi mavisi */
  --accent-color: #c5a3ff; /* Yıldız moru */
  --header-bg: linear-gradient(135deg, #1a1a2e, #16213e);
  --badge-bg: #0f3460;
  --badge-text: #e94560;
  /* Uzaydaki yıldızları andıran çift katmanlı desen */
  --bg-pattern: 
    radial-gradient(circle, #ffffff 1px, transparent 1px), 
    radial-gradient(circle, #ffffff 1px, transparent 1px);
  --bg-size: 40px 40px, 60px 60px;
  background-position: 0 0, 20px 20px;
}

/* =========================================
   GENEL GÖRÜNÜM VE ARKA PLAN
   ========================================= */
body {
  background-color: var(--bg-color);
  background-image: var(--bg-pattern);
  background-size: var(--bg-size);
  color: var(--text-color);
  font-family: 'Nunito', 'Segoe UI', Tahoma, sans-serif; /* Öğrenciler için yumuşak hatlı bir font */
  margin: 0;
  padding: 0;
  transition: background-color 0.5s ease, color 0.5s ease;
}

.page-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
}

/* =========================================
   HEADER (ÜST KISIM)
   ========================================= */
.site-header {
  background: var(--header-bg);
  border-radius: 20px;
  padding: 40px 20px;
  text-align: center;
  color: white;
  margin-bottom: 40px;
  box-shadow: var(--card-shadow);
  border-bottom: 4px solid var(--accent-color);
}

.logo-title {
  font-size: 3rem;
  margin: 0;
  text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
  letter-spacing: 2px;
}

.logo-subtitle {
  font-size: 1.2rem;
  opacity: 0.9;
  margin-bottom: 15px;
}

.header-badge {
  background-color: var(--badge-bg);
  color: var(--badge-text);
  padding: 8px 16px;
  border-radius: 30px;
  font-weight: bold;
  font-size: 0.9rem;
  display: inline-block;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* =========================================
   KARTLAR (SINIF VE OYUNLAR İÇİN)
   ========================================= */
.section-label {
  font-size: 1.5rem;
  font-weight: 800;
  margin-top: 40px;
  margin-bottom: 20px;
  border-left: 5px solid var(--primary-color);
  padding-left: 10px;
}

.grid-sinif, .grid-oyunlar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.card {
  background-color: var(--card-bg);
  border: 2px solid var(--card-border);
  border-radius: 20px;
  padding: 25px;
  text-decoration: none;
  color: var(--text-color);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  box-shadow: var(--card-shadow);
  transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
}

/* Kartların üzerine gelince zıplama efekti */
.card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: var(--primary-color);
  box-shadow: 0 15px 30px rgba(0,0,0,0.15);
}

.card-number, .card-icon {
  font-size: 3rem;
  margin-bottom: 15px;
  background: var(--header-bg);

  -webkit-text-fill-color: transparent;
}

.card-tag {
  background: var(--primary-color);
  color: white;
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: bold;
  margin-bottom: 10px;
}

.card-title {
  font-size: 1.4rem;
  margin: 10px 0;
}

.card-desc {
  font-size: 0.95rem;
  opacity: 0.8;
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-cta {
  font-weight: bold;
  color: var(--accent-color);
  display: flex;
  align-items: center;
  gap: 5px;
  transition: gap 0.3s ease;
}

.card:hover .card-cta {
  gap: 10px; /* Ok işareti sağa kayar */
}

/* =========================================
   TEMA DEĞİŞTİRME BUTONU (Gece/Gündüz)
   ========================================= */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--card-bg);
  border: 2px solid var(--primary-color);
  color: var(--text-color);
  padding: 10px 20px;
  border-radius: 30px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: bold;
  box-shadow: var(--card-shadow);
  z-index: 1000;
  transition: all 0.3s ease;
}

.theme-toggle:hover {
  transform: scale(1.05);
}

.theme-toggle__icon {
  font-size: 1.2rem;
}

/* =========================================
   GİRİŞ ANİMASYONLARI
   ========================================= */
.fade-in-up {
  animation: fadeInUp 0.6s ease-out forwards;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}