/* --- GENEL AYARLAR --- */
:root {
    --primary-color: #ff6b6b; /* Canlı Kırmızı/Pembe */
    --secondary-color: #4ecdc4; /* Canlı Turkuaz */
    --accent-color: #ffe66d; /* Canlı Sarı */
    --dark-color: #2f2f2f;
    --light-bg: #f7f9fc;
    --text-color: #444;
    --card-shadow: 0 10px 20px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.6; 
    color: var(--text-color);
    scroll-behavior: smooth;
    overflow-x: hidden;
    position: relative;
    background: #f0f3f6; /* Hafif gri arka plan */
}

h1, h2, h3 {
    font-family: 'Fredoka One', cursive; /* Eğlenceli başlık fontu */
    font-weight: normal;
}

.container {
    width: 85%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.text-center { text-align: center; }

/* --- 1. HAREKETLİ MATEMATİK ARKA PLANI (CSS Animasyonu) --- */
.area {
    background: #4e54c8;  
    background: -webkit-linear-gradient(to left, #8f94fb, #4e54c8);
    width: 100%;
    height: 100vh;
    position: fixed;
    top: 0; left: 0;
    z-index: -1; /* En arkada dursun */
}

.circles {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    overflow: hidden;
}

.circles li {
    position: absolute;
    display: block;
    list-style: none;
    width: 20px; height: 20px;
    background: rgba(255, 255, 255, 0.2);
    animation: animate 25s linear infinite;
    bottom: -150px;
    
    /* Matematik sembolleri ayarları */
    color: rgba(255, 255, 255, 0.6);
    font-family: 'Fredoka One', sans-serif;
    font-size: 2rem;
    display: flex; align-items: center; justify-content: center;
}

/* Farklı boyut ve sürelerde semboller */
.circles li:nth-child(1) { left: 25%; width: 80px; height: 80px; animation-delay: 0s; font-size: 4rem; }
.circles li:nth-child(2) { left: 10%; width: 20px; height: 20px; animation-delay: 1s; animation-duration: 12s; }
.circles li:nth-child(3) { left: 70%; width: 20px; height: 20px; animation-delay: 1s; }
.circles li:nth-child(4) { left: 40%; width: 60px; height: 60px; animation-delay: 0s; animation-duration: 18s; font-size: 3rem; }
.circles li:nth-child(5) { left: 65%; width: 20px; height: 20px; animation-delay: 0s; }
.circles li:nth-child(6) { left: 75%; width: 110px; height: 110px; animation-delay: 1s; font-size: 5rem; }
.circles li:nth-child(7) { left: 35%; width: 150px; height: 150px; animation-delay: 7s; font-size: 7rem; }
.circles li:nth-child(8) { left: 50%; width: 25px; height: 25px; animation-delay: 1s; animation-duration: 45s; }
.circles li:nth-child(9) { left: 20%; width: 15px; height: 15px; animation-delay: 1s; animation-duration: 35s; }
.circles li:nth-child(10) { left: 85%; width: 150px; height: 150px; animation-delay: 0s; animation-duration: 11s; font-size: 6rem;}

/*Arka Plan Harf Animasyonu*/
@keyframes animate {
    0% { transform: translateY(0) rotate(0deg); opacity: 1; border-radius: 0; }
    100% { transform: translateY(-1000px) rotate(720deg); opacity: 0; border-radius: 50%; }
}

/* --- MENÜ (NAVBAR) --- */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar .logo {
    color: var(--dark-color);
    font-size: 1.8rem;
    font-family: 'Fredoka One', cursive;
}

.navbar .logo .plus { color: var(--primary-color); font-size: 2.2rem; }

.nav-links {
    list-style: none;
    display: flex;
    gap: 20px;
}

.nav-links li a {
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition);
    padding: 8px 12px;
    border-radius: 20px;
}

.nav-links li a:hover {
    background-color: var(--secondary-color);
    color: white;
}

.nav-links li a i { margin-right: 5px; opacity: 0.7; }

/* --- HERO SECTION --- */
.hero {
    height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
}

.hero-content h1 {
    font-size: 4rem;
    margin-bottom: 15px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-content p {
    font-size: 1.5rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

/* --- 2. GİRİŞ ANİMASYONU (Fade In Down) --- */
.fade-in-down {
    animation: fadeInDown 1.5s ease-out;
}

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

/* --- BUTONLAR --- */
.btn-primary {
    display: inline-block;
    background: var(--accent-color);
    color: var(--dark-color);
    padding: 12px 30px;
    text-decoration: none;
    border-radius: 30px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.btn-primary:hover {
    background: white;
    transform: scale(1.05);
}

/* --- BÖLÜM GENEL (SECTION) --- */
.section { padding: 80px 0; background: white; margin: 40px 20px; border-radius: 20px; box-shadow: var(--card-shadow); }
.section.gray-bg { background: var(--light-bg); }

.section-title { text-align: center; font-size: 2.5rem; color: var(--dark-color); margin-bottom: 10px; }
.section-subtitle { text-align: center; font-size: 1.1rem; color: #777; margin-bottom: 50px; }

/* --- 3. KAYNAKLAR (PDF KARTLARI) & KART ANİMASYONU --- */
.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 30px;
}

.card {
    background: var(--light-bg);
    padding: 40px 30px;
    border-radius: 15px;
    text-align: center;
    border: 2px solid transparent;
    transition: var(--transition); /* Hover animasyonu için */
    position: relative;
    overflow: hidden;
}

/* Kart Hover Efekti */
.card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 15px 30px rgba(0,0,0,0.15);
    border-color: var(--secondary-color);
}

.card-icon {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

/* Kart Renkleri */
.book-icon { color: var(--primary-color); }
.plus-icon { color: var(--secondary-color); }
.question-icon { color: #f39c12; }
.list-icon { color: #8e44ad; }

.card h3 { font-size: 1.5rem; color: var(--dark-color); margin-bottom: 10px; }
.card p { font-size: 0.95rem; color: #666; margin-bottom: 25px; flex-grow: 1; }

.btn-card {
    display: block;
    background: var(--dark-color);
    color: white;
    padding: 10px;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: var(--transition);
}

.card:hover .btn-card { background: var(--secondary-color); }

/* Giriş Sırasındaki Kayma Animasyonu */
.slide-up {
    animation: slideUp 0.8s ease-out both;
    opacity: 0;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(40px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- DUYURULAR --- */
.announcement-list { max-width: 800px; margin: 0 auto; }
.announcement-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 20px;
    border-left: 5px solid var(--primary-color);
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.announcement-item .date {
    background: var(--primary-color);
    color: white;
    padding: 8px 12px;
    border-radius: 8px;
    font-weight: bold;
    font-size: 0.9rem;
}

/* --- QUIZ & İLETİŞİM --- */
.quiz-container { background: white; padding: 50px; border-radius: 20px; max-width: 600px; margin: 0 auto; border: 3px dashed var(--accent-color); }
.quiz-big-icon { font-size: 5rem; color: var(--accent-color); margin-bottom: 20px; }
.quiz-container h3 { margin-bottom: 10px; }
.quiz-container p { margin-bottom: 25px; }

.contact-form { max-width: 600px; margin: 0 auto; margin-top: 40px; }
.form-group { margin-bottom: 15px; }
.contact-form input, .contact-form textarea {
    width: 100%;
    padding: 15px;
    border: 2px solid #eee;
    border-radius: 10px;
    font-family: inherit;
    transition: var(--transition);
}

.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: var(--secondary-color); }
.full-width { width: 100%; }

/* --- MOBİL UYUMLULUK --- */
@media (max-width: 768px) {
    .nav-links { display: none; } /* Basit mobil menü (geliştirilebilir) */
    .hero-content h1 { font-size: 2.5rem; }
    .container { width: 90%; }
    .resource-grid { grid-template-columns: 1fr; }
}
/* --- ŞİFRE EKRANI ÖZEL STİLLERİ --- */
#site-login-overlay {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: var(--dark-color); /* Mevcut karanlık rengin */
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999; /* Her şeyin üstünde */
}

.login-card {
    background: white;
    padding: 50px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    width: 90%;
    max-width: 400px;
    border-bottom: 5px solid var(--primary-color);
}

.login-icon {
    font-size: 4rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.login-card input {
    width: 100%;
    padding: 15px;
    margin: 20px 0;
    border: 2px solid #eee;
    border-radius: 10px;
    font-size: 1.1rem;
    text-align: center;
    transition: var(--transition);
}

.login-card input:focus {
    outline: none;
    border-color: var(--secondary-color);
}
/* Hakkında İkonu İçin Hafif Parlama Efekti */
.about-main i {
    text-shadow: 0 0 20px rgba(78, 205, 196, 0.3);
    transition: var(--transition);
}

.about-main:hover i {
    transform: rotate(10deg) scale(1.1);
    color: var(--primary-color);
}

.info-box {
    transition: var(--transition);
}

.info-box:hover {
    transform: translateY(-5px);
    background: white !important;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1) !important;
}
/* Form Input Odaklanma Efekti */
.contact-form input:focus, 
.contact-form textarea:focus {
    border-color: var(--secondary-color) !important;
    background-color: #f9ffff;
}

/* Sosyal Medya İkonları Hover */
.social-links a {
    transition: var(--transition);
}

.social-links a:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

/* Sayfa Altı (Footer) Ayarı */
footer {
    position: relative;
    z-index: 10;
}
.announcement-item {
    transition: var(--transition);
    cursor: default;
}

.announcement-item:hover {
    transform: translateX(10px);
    background-color: #f9f9f9;
}