/* Genel Ayarlar */
body { font-family: 'Poppins', sans-serif; background: #f0f2f5; margin: 0; color: #333; }
header { background: #1a1a1a; color: white; text-align: center; padding: 50px 20px; }
.container { max-width: 1200px; margin: auto; padding: 20px; }

/* Ana Sayfa Kitap Kartları */
.book-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 25px; }
.card { background: white; border-radius: 12px; overflow: hidden; box-shadow: 0 4px 10px rgba(0,0,0,0.1); transition: 0.3s; text-align: center; display: flex; flex-direction: column; }
.card:hover { transform: translateY(-8px); }
.card img { width: 100%; height: 300px; object-fit: cover; }
.card-body { padding: 15px; flex-grow: 1; }
.card-body h3 { font-size: 1.1rem; margin: 10px 0; height: 45px; overflow: hidden; }

/* Butonlar */
.btn { display: inline-block; padding: 10px 15px; border-radius: 6px; text-decoration: none; font-weight: 600; margin: 5px; cursor: pointer; transition: 0.2s; }
.btn-info { background: #3498db; color: white; }
.btn-buy {
    display: block;
    background-color: #e67e22; /* Turuncu renk */
    color: white !important;
    text-align: center;
    padding: 12px;
    text-decoration: none; /* İŞTE BU ÇİZGİYİ KALDIRIR */
    border-radius: 8px;
    font-weight: bold;
    margin-top: 10px;
    transition: 0.3s;
}

.btn-buy:hover {
    background-color: #d35400; /* Üstüne gelince biraz koyulaşsın */
    text-decoration: none; /* Garanti olsun diye burada da kalsın */
}
.btn:hover { opacity: 0.9; }

/* Detay Sayfası */
.detail-box { background: white; padding: 40px; border-radius: 15px; display: flex; gap: 40px; flex-wrap: wrap; margin-top: 20px; }
.detail-img { width: 300px; border-radius: 10px; box-shadow: 0 10px 20px rgba(0,0,0,0.2); }
.detail-text { flex: 1; min-width: 300px; }
.back-home { color: #3498db; text-decoration: none; font-weight: bold; display: block; margin-bottom: 20px; }
/* Ana Sayfaya Dön Butonu Tasarımı */
.btn-back {
    display: inline-block;
    padding: 10px 20px;
    background-color: #2c3e50; /* Koyu şık bir gri-mavi */
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    margin-bottom: 25px;
    transition: all 0.3s ease;
    border: none;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.btn-back:hover {
    background-color: #34495e;
    transform: translateX(-5px); /* Hafif sola kayma efekti (Geri gitme hissi verir) */
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}
/* İletişim Kutusu Tasarımı */
.contact-container {
    background: #ffffff;
    max-width: 800px;
    margin: 50px auto; /* Ortalamak için */
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 15px 35px rgba(0,0,0,0.05); /* Yumuşak bir gölge */
    border: 1px solid #eee;
}

.contact-container h3 {
    font-size: 2rem;
    color: #2c3e50;
    margin-bottom: 15px;
    font-weight: 600;
}

.contact-container p {
    color: #7f8c8d;
    font-size: 1.1rem;
    line-height: 1.6;
    margin-bottom: 30px;
}

/* Butonu biraz daha büyütüp parlatalım */
.btn-email {
    display: inline-block;
    background: linear-gradient(135deg, #27ae60, #2ecc71);
    color: white !important;
    padding: 18px 40px;
    border-radius: 50px; /* Tam yuvarlak buton */
    text-decoration: none;
    font-weight: bold;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 10px 20px rgba(39, 174, 96, 0.2);
}

.btn-email:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 25px rgba(39, 174, 96, 0.3);
}
/* --- YENİ EKLENEN TASARIMLAR --- */

/* Üst Başlık (Hero) Alanı */
.hero-section {
    background: linear-gradient(135deg, #1a1a1a 0%, #2c3e50 100%);
    padding: 80px 20px;
    text-align: center;
    color: white;
    border-bottom: 4px solid #27ae60;
}

.hero-section h1 {
    font-size: 3rem;
    letter-spacing: 2px;
    margin-bottom: 10px;
    text-transform: uppercase;
}

/* İletişim Kutusu */
.contact-container {
    background: #ffffff;
    max-width: 800px;
    margin: 50px auto;
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 15px 35px rgba(0,0,0,0.05);
    border: 1px solid #eee;
}

/* Yeşil Buton */
.btn-email {
    display: inline-block;
    background: linear-gradient(135deg, #27ae60, #2ecc71);
    color: white !important;
    padding: 15px 35px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    margin-top: 10px;
    transition: 0.3s;
}

.btn-email:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(39,174, 96, 0.2);
}
/* Dark Mode Renkleri */
body.dark-mode {
    background-color: #121212;
    color: #e0e0e0;
}

body.dark-mode .container {
    background-color: #121212;
}

body.dark-mode .detail-box {
    background-color: #1e1e1e;
    color: #ffffff;
    box-shadow: 0 4px 15px rgba(0,0,0,0.5);
}

body.dark-mode h1, body.dark-mode h3 {
    color: #bb86fc; /* Başlıklar için tatlı bir mor */
}

body.dark-mode .btn-back {
    color: #bb86fc;
}

body.dark-mode hr {
    border-color: #333;
}
.dark-mode-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 10px 15px;
    background-color: #333;
    color: white;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    z-index: 1000;
    font-family: 'Poppins', sans-serif;
    transition: 0.3s;
}

body.dark-mode .dark-mode-btn {
    background-color: #f1f1f1;
    color: #333;
}