/* --- GENEL RESETLEME VE AYARLAR --- */
:root {
    --primary-color: #2a6fdb; /* Ana Mavi */
    --secondary-color: #f4b400; /* Vurgu Sarısı */
    --dark-color: #333;
    --light-color: #f4f4f4;
    --font-family: 'Poppins', sans-serif;
}

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

body {
    font-family: var(--font-family);
    line-height: 1.6;
    background: #fff;
    color: var(--dark-color);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

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

ul {
    list-style: none;
}

h1, h2, h3 {
    margin-bottom: 1rem;
}

/* --- YARDIMCI SINIFLAR (UTILITIES) --- */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 5px;
    background: var(--primary-color);
    color: #fff;
    border: none;
    cursor: pointer;
    transition: background 0.3s ease;
}

.btn:hover {
    background: #1e5ba3;
}

.btn-primary {
    background: var(--primary-color);
}

.btn-secondary {
    background: var(--secondary-color);
    color: #333;
}

.btn-secondary:hover {
    background: #d69e00;
}

.btn-lg {
    padding: 15px 30px;
    font-size: 1.1rem;
}


/* --- HEADER --- */
.main-header {
    background: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark-color);
}

.logo i {
    color: var(--primary-color);
    margin-right: 8px;
}

.main-nav ul {
    display: flex;
}

.main-nav ul li a {
    padding: 10px 15px;
    color: var(--dark-color);
    font-weight: 600;
    transition: color 0.3s ease;
}

.main-nav ul li a:hover {
    color: var(--primary-color);
}

.header-actions .mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* --- HERO SECTION (ANA SAYFA) --- */
.hero {
    background: linear-gradient(rgba(42, 111, 219, 0.8), rgba(42, 111, 219, 0.8)), url('https://images.unsplash.com/photo-1454165804606-c3d57bc86b40?auto=format&fit=crop&w=1170&q=80');
    background-size: cover;
    background-position: center;
    color: #fff;
    text-align: center;
    padding: 100px 0;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 30px;
}

/* --- FEATURES SECTION (ANA SAYFA) --- */
.features {
    padding: 60px 0;
    text-align: center;
}

.features .container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.features .feature i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.features .feature h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}


/* --- FOOTER --- */
.main-footer {
    background: var(--dark-color);
    color: #fff;
    padding: 2rem 0;
    text-align: center;
}

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

.social-links a {
    color: #fff;
    margin-left: 15px;
    font-size: 1.3rem;
    transition: color 0.3s ease;
}

.social-links a:hover {
    color: var(--secondary-color);
}


/* --- RESPONSIVE TASARIM --- */
@media(max-width: 768px) {
    .main-header .container {
        position: relative;
    }

    .main-nav {
        display: none; /* Mobil menüyü gizle */
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: #fff;
        box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    }
    
    .main-nav.active {
        display: block; /* Aktif olunca göster */
    }

    .main-nav ul {
        flex-direction: column;
        text-align: center;
    }

    .main-nav ul li {
        padding: 15px 0;
        border-top: 1px solid #eee;
    }

    .header-actions .btn, .header-actions .btn-logout {
        display: none;
    }

    .header-actions .mobile-menu-btn {
        display: block;
    }

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

    .hero h1 {
        font-size: 2.2rem;
    }

    .main-footer .container {
        flex-direction: column;
    }

    .main-footer p {
        margin-bottom: 1rem;
    }
}

/* --- ORTAK SAYFA BAŞLIĞI (Hakkımda, İletişim vb.) --- */
.page-header {
    background: var(--light-color);
    padding: 40px 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    color: var(--dark-color);
}

/* --- HAKKIMDA SAYFASI --- */
.about-content {
    padding: 60px 0;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 40px;
    align-items: center;
}

.about-image img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.about-text h2 {
    color: var(--primary-color);
    font-size: 2rem;
}

.about-text h3 {
    margin-top: 2rem;
    border-bottom: 2px solid var(--light-color);
    padding-bottom: 0.5rem;
}

.about-text ul {
    margin-top: 1rem;
}

.about-text ul li {
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.about-text ul li i {
    color: var(--primary-color);
    margin-right: 10px;
}

/* Hakkımda sayfası için responsive */
@media(max-width: 768px) {
    .about-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .about-image {
        margin-bottom: 2rem;
    }
}

/* --- İLETİŞİM FORMU --- */
.contact-form-section {
    padding: 60px 0;
}

#application-form {
    max-width: 700px;
    margin: 0 auto;
    background: var(--light-color);
    padding: 40px;
    border-radius: 10px;
}

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

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-family: var(--font-family);
}

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

#application-form button {
    width: 100%;
    padding: 15px;
    font-size: 1.1rem;
}

/* Form Bildirim Mesajları */
.form-message {
    max-width: 700px;
    margin: 0 auto 20px auto;
    padding: 15px;
    border-radius: 5px;
    text-align: center;
}
.form-message.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}
.form-message.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* --- GİRİŞ/KAYIT FORMLARI --- */
.auth-form-section {
    padding: 60px 0;
}

#login-form, #register-form { /* Register formunu ileride kullanacağız */
    max-width: 500px;
    margin: 0 auto;
    background: var(--light-color);
    padding: 40px;
    border-radius: 10px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 15px; /* Butonlar arası boşluk */
}

.btn-logout {
    color: var(--dark-color);
    font-weight: 600;
    font-size: 0.9rem;
}

.btn-logout i {
    margin-right: 5px;
}

/* --- Hata Sayfası --- */
.error-page {
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    min-height: 60vh;
}
.error-page h1 {
    font-size: 8rem;
    color: var(--primary-color);
    margin: 0;
    line-height: 1;
}
.error-page h2 {
    font-size: 2rem;
}
.error-page p {
    margin-bottom: 2rem;
}

/* ... Genel stillerin olduğu yere ekleyin ... */
.nav-mobile-only {
    display: none; /* Varsayılan olarak (masaüstünde) gizli */
}
.nav-mobile-only a.btn {
    display: block;
    margin: 10px 20px 0 20px;
    text-align: center;
}


/* ... @media kuralının içine ekleyin ... */
@media(max-width: 768px) {
    /* ... */
    .nav-mobile-only {
        display: block; /* Mobilde göster */
    }
    .nav-mobile-only a {
        display: block;
        padding: 10px 15px;
    }
    /* ... */
}