/* ========================================
   Canfenci - Fen Bilimleri Döküman Arşivi
   Ana Stil Dosyası
   ======================================== */

/* ===== CSS Değişkenleri ===== */
:root {
  --primary-color: #1B3A5C;
  --secondary-color: #E67E22;
  --bg-light: #F5F6FA;
  --text-dark: #2C3E50;
  --text-light: #7F8C8D;
  --white: #FFFFFF;
  --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 5px 20px rgba(0, 0, 0, 0.15);
  --transition: all 0.3s ease;
  --border-radius: 12px;
  --font-heading: 'Poppins', sans-serif;
  --font-body: 'Open Sans', sans-serif;
}

/* ===== Reset & Base Styles ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--text-dark);
  background-color: var(--bg-light);
  line-height: 1.6;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.3;
}

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

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

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

/* ===== Container ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Header ===== */
header {
  background-color: var(--white);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: var(--transition);
}

header.scrolled {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 0;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
}

.logo img {
  height: 65px;
  width: auto;
  display: block;
}

.logo-text {
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
}

/* Eski logo-circle stilini kaldırın veya yorum satırı yapın */
.logo-circle {
  display: none; /* Artık kullanılmıyor */
}



.nav-menu {
  display: flex;
  list-style: none;
  gap: 30px;
  align-items: center;
}

.nav-menu a {
  color: var(--text-dark);
  font-weight: 500;
  padding: 8px 16px;
  border-radius: 8px;
  transition: var(--transition);
}

.nav-menu a:hover,
.nav-menu a.active {
  background-color: var(--secondary-color);
  color: var(--white);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: 5px;
}

.hamburger span {
  width: 28px;
  height: 3px;
  background-color: var(--primary-color);
  border-radius: 3px;
  transition: var(--transition);
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(8px, 8px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(8px, -8px);
}

/* ===== Hero Section ===== */
.hero {
  background: linear-gradient(135deg, var(--primary-color), #2C5F8D);
  color: var(--white);
  padding: 100px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 120"><path fill="%23ffffff" fill-opacity="0.05" d="M0,0 Q300,60 600,30 T1200,50 L1200,120 L0,120 Z"/></svg>') bottom center no-repeat;
  background-size: cover;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: 48px;
  margin-bottom: 20px;
  animation: fadeInUp 0.8s ease;
}

.hero p {
  font-size: 20px;
  margin-bottom: 30px;
  opacity: 0.95;
  animation: fadeInUp 1s ease;
}

.btn-primary {
  background-color: var(--secondary-color);
  color: var(--white);
  padding: 14px 35px;
  border-radius: 50px;
  font-size: 16px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  box-shadow: 0 4px 15px rgba(230, 126, 34, 0.3);
  animation: fadeInUp 1.2s ease;
}

.btn-primary:hover {
  background-color: #D35400;
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(230, 126, 34, 0.4);
}

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

/* ===== Section Styles ===== */
section {
  padding: 80px 0;
}

.section-title {
  text-align: center;
  margin-bottom: 50px;
}

.section-title h2 {
  font-size: 36px;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.section-title p {
  font-size: 18px;
  color: var(--text-light);
}

/* ===== Grid Layouts ===== */
.grid {
  display: grid;
  gap: 30px;
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* ===== Cards ===== */
.card {
  background-color: var(--white);
  border-radius: var(--border-radius);
  padding: 30px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  text-align: center;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-hover);
}

.card-icon {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--secondary-color), #D35400);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  font-size: 36px;
  color: var(--white);
}

.card h3 {
  font-size: 22px;
  color: var(--primary-color);
  margin-bottom: 15px;
}

.card p {
  color: var(--text-light);
  margin-bottom: 20px;
}

.btn-secondary {
  background-color: var(--primary-color);
  color: var(--white);
  padding: 10px 25px;
  border-radius: 8px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-secondary:hover {
  background-color: #2C5F8D;
}

/* ===== Feature Cards ===== */
.feature-card {
  background-color: var(--white);
  border-radius: var(--border-radius);
  padding: 30px;
  box-shadow: var(--shadow);
  display: flex;
  align-items: flex-start;
  gap: 20px;
  transition: var(--transition);
}

.feature-card:hover {
  box-shadow: var(--shadow-hover);
}

.feature-icon {
  width: 60px;
  height: 60px;
  background-color: rgba(230, 126, 34, 0.1);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  color: var(--secondary-color);
  flex-shrink: 0;
}

.feature-content h3 {
  font-size: 20px;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.feature-content p {
  color: var(--text-light);
}

/* ===== Document Cards ===== */
.doc-card {
  background-color: var(--white);
  border-radius: var(--border-radius);
  padding: 20px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

.doc-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
}

.doc-category {
  display: inline-block;
  background-color: var(--secondary-color);
  color: var(--white);
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 15px;
  align-self: flex-start;
}

.doc-category.konu {
  background-color: #3498DB;
}

.doc-category.calisma {
  background-color: #9B59B6;
}

.doc-category.yazili {
  background-color: #E74C3C;
}

.doc-category.dijital {
  background-color: #1ABC9C;
}

.doc-icon {
  font-size: 48px;
  color: var(--secondary-color);
  margin-bottom: 15px;
  text-align: center;
}

.doc-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.doc-meta {
  display: flex;
  gap: 15px;
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 15px;
  flex-wrap: wrap;
}

.doc-meta span {
  display: flex;
  align-items: center;
  gap: 5px;
}

.btn-download {
  background-color: var(--secondary-color);
  color: var(--white);
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: auto;
}

.btn-download:hover {
  background-color: #D35400;
}

/* ===== Filter Buttons ===== */
.filter-buttons {
  display: flex;
  justify-content: center;
  gap: 15px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.filter-btn {
  background-color: var(--white);
  color: var(--text-dark);
  padding: 10px 25px;
  border-radius: 25px;
  font-weight: 600;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--secondary-color);
  color: var(--white);
}

/* ===== Page Header ===== */
.page-header {
  background: linear-gradient(135deg, var(--primary-color), #2C5F8D);
  color: var(--white);
  padding: 60px 0;
  text-align: center;
  margin-bottom: 50px;
}

.page-header h1 {
  font-size: 42px;
  margin-bottom: 10px;
}

.page-header p {
  font-size: 18px;
  opacity: 0.9;
}

/* ===== Stats Counter ===== */
.stats-container {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
  margin: 50px 0;
}

.stat-box {
  background-color: var(--white);
  border-radius: var(--border-radius);
  padding: 40px 30px;
  text-align: center;
  box-shadow: var(--shadow);
}

.stat-number {
  font-size: 48px;
  font-weight: 700;
  color: var(--secondary-color);
  margin-bottom: 10px;
}

.stat-label {
  font-size: 18px;
  color: var(--text-light);
}

/* ===== Contact Form ===== */
.contact-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 50px;
  align-items: start;
}

.contact-form {
  background-color: var(--white);
  padding: 40px;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: var(--primary-color);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 15px;
  border: 2px solid #E0E0E0;
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 15px;
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--secondary-color);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.btn-submit {
  background-color: var(--secondary-color);
  color: var(--white);
  padding: 14px 40px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.btn-submit:hover {
  background-color: #D35400;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.info-box {
  background-color: var(--white);
  padding: 30px;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  display: flex;
  align-items: flex-start;
  gap: 20px;
}

.info-icon {
  width: 50px;
  height: 50px;
  background-color: rgba(230, 126, 34, 0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  color: var(--secondary-color);
  flex-shrink: 0;
}

.info-content h3 {
  font-size: 18px;
  color: var(--primary-color);
  margin-bottom: 8px;
}

.info-content p {
  color: var(--text-light);
}

/* ===== Footer ===== */
footer {
  background-color: var(--primary-color);
  color: var(--white);
  padding: 50px 0 20px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 30px;
}

.footer-section h3 {
  font-size: 20px;
  margin-bottom: 20px;
}

.footer-section p {
  opacity: 0.9;
  line-height: 1.8;
}

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

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  opacity: 0.9;
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-links a:hover {
  opacity: 1;
  color: var(--secondary-color);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 20px;
  text-align: center;
  opacity: 0.8;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.visitor-counter {
  font-size: 13.5px;
  color: #a0aec0;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: rgba(255, 255, 255, 0.05);
  padding: 6px 16px;
  border-radius: 20px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.3s ease;
}

.visitor-counter:hover {
  background-color: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
}

.visitor-counter span {
  color: #ff8c42;
  font-weight: 700;
}

/* ===== Responsive Design ===== */

/* Tablet (768px) */
@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    flex-direction: column;
    background-color: var(--white);
    padding: 30px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    gap: 20px;
  }

  .nav-menu.active {
    left: 0;
  }

  .hamburger {
    display: flex;
  }

  .hero h1 {
    font-size: 36px;
  }

  .hero p {
    font-size: 18px;
  }

  .section-title h2 {
    font-size: 30px;
  }

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .stats-container {
    grid-template-columns: 1fr;
  }

  .contact-container {
    grid-template-columns: 1fr;
  }

  .footer-content {
    grid-template-columns: 1fr;
  }
}

/* Mobile (480px) */
@media (max-width: 480px) {
  .hero {
    padding: 60px 0;
  }

  .hero h1 {
    font-size: 28px;
  }

  .hero p {
    font-size: 16px;
  }

  .section-title h2 {
    font-size: 24px;
  }

  .grid-4,
  .grid-3,
  .grid-2 {
    grid-template-columns: 1fr;
  }

  .filter-buttons {
    flex-direction: column;
  }

  .filter-btn {
    width: 100%;
  }

  .page-header h1 {
    font-size: 32px;
  }

  .card {
    padding: 20px;
  }

  .feature-card {
    flex-direction: column;
    text-align: center;
  }

  .contact-form {
    padding: 25px;
  }
}

/* ===== Utility Classes ===== */
.text-center {
  text-align: center;
}

.mt-20 {
  margin-top: 20px;
}

.mb-20 {
  margin-bottom: 20px;
}

.hidden {
  display: none;
}
/* ========================================
   SIDEBAR FİLTRELEME SİSTEMİ (EBA Stili)
   ======================================== */

/* Sayfa düzeni - İki sütunlu yapı */
.page-layout {
  display: flex;
  gap: 24px;
  align-items: flex-start;
  margin-left: -20px;
}

/* Sol Sidebar */
.sidebar {
  width: 25%;
  flex: 0 0 calc(25% - 18px);
  position: sticky;
  top: 90px;
  align-self: flex-start;
  padding: 4px;
  box-sizing: border-box;
}

.sidebar-header {
  padding: 0 0 10px;
  margin-bottom: 4px;
}

.sidebar-header h3 {
  font-size: 11px;
  font-weight: 700;
  color: var(--text-light);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin: 0;
}

.sidebar-filters {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 0;
}

/* ===== EBA Tarzı Filtre Butonları ===== */
.sidebar-filter-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  text-align: left;
  padding: 9px 11px;
  font-size: 13px;
  font-weight: 600;
  border: 1.5px solid transparent;
  border-radius: 11px;
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
  color: #555;
  background: var(--white);
  box-shadow: 0 1px 5px rgba(0, 0, 0, 0.06);
}

.sidebar-filter-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  opacity: 0;
  transition: opacity 0.25s ease;
  border-radius: 10px;
  z-index: 0;
}

.sidebar-filter-btn i {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 9px;
  font-size: 15px;
  flex-shrink: 0;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  z-index: 1;
}

.sidebar-filter-btn span,
.sidebar-filter-btn {
  position: relative;
  z-index: 1;
}

/* Hover efekti */
.sidebar-filter-btn:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}

/* ===== Her Kategori İçin Renk Teması ===== */

/* Tümü */
.sidebar-filter-btn[data-filter="all"] i {
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #fff;
}
.sidebar-filter-btn[data-filter="all"].active,
.sidebar-filter-btn[data-filter="all"]:hover {
  background: linear-gradient(135deg, #f0efff, #ece7ff);
  border-color: #764ba2;
  color: #764ba2;
}
.sidebar-filter-btn[data-filter="all"].active i {
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #fff;
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
  transform: scale(1.08);
}

/* Konu Anlatımı */
.sidebar-filter-btn[data-filter="konu"] i {
  background: linear-gradient(135deg, #3498db, #2980b9);
  color: #fff;
}
.sidebar-filter-btn[data-filter="konu"].active,
.sidebar-filter-btn[data-filter="konu"]:hover {
  background: linear-gradient(135deg, #ebf5ff, #dbeeff);
  border-color: #3498db;
  color: #2980b9;
}
.sidebar-filter-btn[data-filter="konu"].active i {
  background: linear-gradient(135deg, #3498db, #2980b9);
  color: #fff;
  box-shadow: 0 4px 12px rgba(52, 152, 219, 0.4);
  transform: scale(1.08);
}

/* Çalışma Kağıtları */
.sidebar-filter-btn[data-filter="calisma"] i {
  background: linear-gradient(135deg, #9b59b6, #8e44ad);
  color: #fff;
}
.sidebar-filter-btn[data-filter="calisma"].active,
.sidebar-filter-btn[data-filter="calisma"]:hover {
  background: linear-gradient(135deg, #f5eeff, #ece0ff);
  border-color: #9b59b6;
  color: #8e44ad;
}
.sidebar-filter-btn[data-filter="calisma"].active i {
  background: linear-gradient(135deg, #9b59b6, #8e44ad);
  color: #fff;
  box-shadow: 0 4px 12px rgba(155, 89, 182, 0.4);
  transform: scale(1.08);
}

/* Yazılılar */
.sidebar-filter-btn[data-filter="yazili"] i {
  background: linear-gradient(135deg, #e74c3c, #c0392b);
  color: #fff;
}
.sidebar-filter-btn[data-filter="yazili"].active,
.sidebar-filter-btn[data-filter="yazili"]:hover {
  background: linear-gradient(135deg, #fef0ef, #fde3e1);
  border-color: #e74c3c;
  color: #c0392b;
}
.sidebar-filter-btn[data-filter="yazili"].active i {
  background: linear-gradient(135deg, #e74c3c, #c0392b);
  color: #fff;
  box-shadow: 0 4px 12px rgba(231, 76, 60, 0.4);
  transform: scale(1.08);
}

/* Dijital İçerik */
.sidebar-filter-btn[data-filter="dijital"] i {
  background: linear-gradient(135deg, #1abc9c, #16a085);
  color: #fff;
}
.sidebar-filter-btn[data-filter="dijital"].active,
.sidebar-filter-btn[data-filter="dijital"]:hover {
  background: linear-gradient(135deg, #e8faf6, #d5f5ec);
  border-color: #1abc9c;
  color: #16a085;
}
.sidebar-filter-btn[data-filter="dijital"].active i {
  background: linear-gradient(135deg, #1abc9c, #16a085);
  color: #fff;
  box-shadow: 0 4px 12px rgba(26, 188, 156, 0.4);
  transform: scale(1.08);
}

/* Video Anlatım */
.sidebar-filter-btn[data-filter="video"] i {
  background: linear-gradient(135deg, #f39c12, #e67e22);
  color: #fff;
}
.sidebar-filter-btn[data-filter="video"].active,
.sidebar-filter-btn[data-filter="video"]:hover {
  background: linear-gradient(135deg, #fff9f0, #ffebd1);
  border-color: #f39c12;
  color: #e67e22;
}
.sidebar-filter-btn[data-filter="video"].active i {
  background: linear-gradient(135deg, #f39c12, #e67e22);
  color: #fff;
  box-shadow: 0 4px 12px rgba(243, 156, 18, 0.4);
  transform: scale(1.08);
}

/* Testler */
.sidebar-filter-btn[data-filter="test"] i {
  background: linear-gradient(135deg, #fd79a8, #e84393);
  color: #fff;
}
.sidebar-filter-btn[data-filter="test"].active,
.sidebar-filter-btn[data-filter="test"]:hover {
  background: linear-gradient(135deg, #fff0f5, #ffd9e8);
  border-color: #fd79a8;
  color: #e84393;
}
.sidebar-filter-btn[data-filter="test"].active i {
  background: linear-gradient(135deg, #fd79a8, #e84393);
  color: #fff;
  box-shadow: 0 4px 12px rgba(253, 121, 168, 0.4);
  transform: scale(1.08);
}

/* Aktif butonun genel stili */
.sidebar-filter-btn.active {
  font-weight: 700;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  transform: translateX(4px);
}

/* ===== Kategori sayacı badge (opsiyonel) ===== */
.sidebar-filter-btn .filter-count {
  margin-left: auto;
  background: rgba(0, 0, 0, 0.08);
  color: inherit;
  font-size: 12px;
  font-weight: 700;
  padding: 2px 10px;
  border-radius: 20px;
  min-width: 28px;
  text-align: center;
}

.sidebar-filter-btn.active .filter-count {
  background: rgba(0, 0, 0, 0.1);
}

/* Sağ içerik alanı */
.content-area {
  width: 75%;
  flex: 0 0 calc(75% - 6px);
  min-width: 0;
}

/* Eski filter-buttons gizle */
.filter-buttons {
  display: none;
}

@media (max-width: 1024px) {
  .sidebar {
    width: 25%;
    flex: 0 0 calc(25% - 18px);
  }
  
  .sidebar-filter-btn {
    padding: 8px 10px;
    gap: 8px;
    font-size: 12px;
  }

  .sidebar-filter-btn i {
    width: 28px;
    height: 28px;
    font-size: 13px;
    border-radius: 8px;
  }
}

/* ===== MOBİL GÖRÜNÜM (Tablet ve altı) ===== */
@media (max-width: 768px) {
  .page-layout {
    flex-direction: column;
    gap: 20px;
    margin-left: 0;
  }

  .sidebar {
    width: 100%;
    flex: none;
    min-width: unset;
    position: relative;
    top: 0;
    max-height: none;
    overflow: visible;
  }

  .content-area {
    width: 100%;
    flex: none;
  }

  .sidebar-header {
    padding: 0 4px 10px;
  }

  .sidebar-header h3 {
    font-size: 11px;
  }

  .sidebar-filters {
    display: flex;
    flex-direction: row;
    overflow-x: auto;
    padding: 4px 0;
    gap: 10px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    scroll-snap-type: x mandatory;
  }

  .sidebar-filters::-webkit-scrollbar {
    display: none;
  }

  .sidebar-filter-btn {
    flex-shrink: 0;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 8px;
    padding: 14px 16px;
    min-width: 100px;
    border-radius: 16px;
    scroll-snap-align: start;
    font-size: 12px;
  }

  .sidebar-filter-btn i {
    width: 44px;
    height: 44px;
    font-size: 20px;
    border-radius: 14px;
  }

  .sidebar-filter-btn:hover,
  .sidebar-filter-btn.active {
    transform: translateY(-2px) !important;
  }

  .sidebar-filter-btn .filter-count {
    display: none;
  }

  .content-area {
    width: 100%;
  }
}

/* ===== MOBİL KÜÇÜK (480px ve altı) ===== */
@media (max-width: 480px) {
  .sidebar-filter-btn {
    padding: 12px 12px;
    min-width: 88px;
    font-size: 11px;
  }

  .sidebar-filter-btn i {
    width: 38px;
    height: 38px;
    font-size: 17px;
    border-radius: 12px;
  }
}

/* Dijital İçerik bölümü için özel grid (grid-3'ten bağımsız) */
.dijital-icerik-wrapper {
  margin-top: 40px;
}

.dijital-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
  margin-top: 20px;
}

/* Section header düzeni */
.section-header {
  text-align: center;
  margin: 40px 0 20px;
}

.section-header h2 {
  font-size: 28px;
  color: #2c3e66;
  margin-bottom: 8px;
}

.section-header p {
  color: #6c7a8a;
  font-size: 15px;
}

/* ========================================
   HİYERARŞİK BÖLÜM VE SEKME SİSTEMİ (CSS)
   ======================================== */

.unit-section {
  display: none;
  animation: fadeInUp 0.4s ease;
}

.unit-section.active {
  display: block;
}

.chapter-list {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.chapter-card {
  background-color: var(--white);
  border-radius: 16px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
  border: 1px solid rgba(0, 0, 0, 0.05);
  overflow: hidden;
  transition: all 0.3s ease;
  margin-bottom: 20px;
}

.chapter-card-header {
  padding: 20px 24px;
  background: linear-gradient(135deg, #f8fafd, #f1f5fa);
  border-bottom: 1px solid #eef2f7;
}

.chapter-card-header h4 {
  font-size: 17px;
  color: #1a2a44;
  margin: 0 0 4px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
}

.chapter-card-header p {
  color: #64748b;
  font-size: 13.5px;
  margin: 0;
}

.chapter-tabs {
  display: flex;
  background-color: #f8fafc;
  border-bottom: 1px solid #e2e8f0;
  padding: 0 16px;
  overflow-x: auto;
  scrollbar-width: none;
}

.chapter-tabs::-webkit-scrollbar {
  display: none;
}

.chapter-tab-btn {
  background: transparent;
  border: none;
  padding: 12px 18px;
  font-size: 13px;
  font-weight: 600;
  color: #64748b;
  cursor: pointer;
  border-bottom: 3px solid transparent;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.chapter-tab-btn:hover {
  color: #1a2a44;
}

.chapter-tab-btn.active {
  color: #ff8c42;
  border-bottom-color: #ff8c42;
}

.chapter-tab-content {
  padding: 20px 24px;
  background-color: var(--white);
}

.tab-pane {
  display: none;
  animation: fadeInUp 0.3s ease;
}

.tab-pane.active {
  display: block;
}

.pdf-list-container {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* Pane içindeki indir/etkinlik tasarımları */
.pane-pdf-info {
  display: flex;
  align-items: center;
  gap: 20px;
  background-color: #f8fafc;
  padding: 14px 18px;
  border-radius: 12px;
  border: 1px solid #e2e8f0;
}

.pdf-large-icon {
  font-size: 32px;
  color: #ef4444;
}

.code-large-icon {
  font-size: 32px;
  color: #10b981;
}

.video-large-icon {
  font-size: 32px;
  color: #ff0000;
}

.test-large-icon {
  font-size: 32px;
  color: #9b59b6;
}

.pane-pdf-info h5 {
  font-size: 14.5px;
  color: #1e293b;
  margin: 0 0 4px;
  font-weight: 600;
}

.pane-pdf-info p {
  color: #64748b;
  font-size: 12.5px;
  margin: 0;
}

.pane-pdf-info .btn-download {
  margin-left: auto;
  background-color: #ff8c42;
  color: white;
  padding: 8px 16px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 13px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all 0.2s ease;
}

.pane-pdf-info .btn-download:hover {
  background-color: #e07b38;
  transform: translateY(-1px);
}

.video-embed-container {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

/* Genel Sidebar Ünite Butonları */
.sidebar-filter-btn i {
  background: linear-gradient(135deg, #2c3e50, #34495e);
  color: #fff;
}

.sidebar-filter-btn:hover,
.sidebar-filter-btn.active {
  background: linear-gradient(135deg, #f0f4f8, #e2ebf0);
  border-color: #34495e;
  color: #2c3e50;
}

.sidebar-filter-btn.active i {
  background: linear-gradient(135deg, #2c3e50, #34495e);
  color: #fff;
  box-shadow: 0 4px 12px rgba(44, 62, 80, 0.4);
  transform: scale(1.08);
}