/* ==========================================================================
   Synapze — Sade, Hızlı ve Mobil Uyumlu Akademik Çalışma Tasarımı
   (Sıfır kasma / donma, sıfır ağır efekt, doğal ve okunaklı arayüz)
   ========================================================================== */

:root {
  --bg-page: #F8FAFC;
  --bg-surface: #FFFFFF;
  --bg-muted: #F1F5F9;
  --border-color: #E2E8F0;
  --border-strong: #CBD5E1;
  --text-main: #0F172A;
  --text-secondary: #475569;
  --text-muted: #64748B;
  --accent: #2563EB;
  --accent-hover: #1D4ED8;
  --accent-soft: #EFF6FF;
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-page);
  color: var(--text-main);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* Hafif ve sade kaydırma çubuğu */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: #F1F5F9;
}

::-webkit-scrollbar-thumb {
  background: #CBD5E1;
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: #94A3B8;
}

/* Temiz Kart Yapısı (Blur veya ağır gölge yok, maksimum performans) */
.clean-card {
  background-color: #FFFFFF;
  border: 1px solid #E2E8F0;
  border-radius: 10px;
}

/* Sekme Butonları */
.tab-item {
  border-bottom: 2px solid transparent;
  color: #475569;
  font-weight: 500;
  transition: color 120ms ease, border-color 120ms ease;
}

.tab-item:hover {
  color: #0F172A;
}

.tab-item.active {
  color: #2563EB;
  border-bottom-color: #2563EB;
  font-weight: 600;
}

/* Mobil Alt Bar Aktif Sekme */
.mobile-nav-btn {
  color: #64748B;
}

.mobile-nav-btn.active {
  color: #2563EB;
  font-weight: 600;
}

/* Soru Seçenekleri */
.option-btn {
  border: 1px solid #E2E8F0;
  background-color: #FFFFFF;
  text-align: left;
  transition: background-color 100ms ease, border-color 100ms ease;
}

.option-btn:hover {
  background-color: #F8FAFC;
  border-color: #CBD5E1;
}

.option-btn.correct {
  background-color: #F0FDF4;
  border-color: #22C55E;
  color: #14532D;
}

.option-btn.wrong {
  background-color: #FEF2F2;
  border-color: #EF4444;
  color: #7F1D1D;
}

/* Yükleme Alanı */
.dropzone-box {
  border: 2px dashed #CBD5E1;
  background-color: #F8FAFC;
  transition: border-color 120ms ease, background-color 120ms ease;
}

.dropzone-box:hover,
.dropzone-box.dragover {
  border-color: #2563EB;
  background-color: #EFF6FF;
}

/* Basit Dönen Yükleme İkonu */
@keyframes simpleSpin {
  to { transform: rotate(360deg); }
}

.spinner {
  width: 20px;
  height: 20px;
  border: 2.5px solid #CBD5E1;
  border-top-color: #2563EB;
  border-radius: 50%;
  animation: simpleSpin 0.7s linear infinite;
}

@media print {
  .no-print {
    display: none !important;
  }
}