/* ==========================================
   1. DEĞİŞKENLER VE TEMEL SIFIRLAMA
   ========================================== */
:root {
    --primary: #1b3b36;
    --accent: #2a7f62;
    --wood: #c08552;
    --dark: #121212;
    --light: #f8f9fa;
}

*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

html, body {
    width: 100%;
    overflow-x: hidden;
    background-color: var(--light);
    color: #333;
    line-height: 1.6;
}

/* ==========================================
   2. GİZLİ SÜZÜLEN GEZİNTİ ÇUBUĞU (NAVBAR)
   ========================================== */
nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    z-index: 1000;
    background: rgba(27, 59, 54, 0.95);
    backdrop-filter: blur(8px);
    padding: 0 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    overflow: hidden;
    
    /* JS Fare Efekti için Gizleme */
    transform: translateY(-100%);
    opacity: 0;
    transition: transform 0.4s ease, opacity 0.4s ease;
}

nav.visible {
    transform: translateY(0);
    opacity: 1;
}

.logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.nav-logo {
    max-height: 45px;
    width: auto;
    max-width: 180px;
    object-fit: contain;
    display: block;
    transition: transform 0.3s ease;
}

.logo-link:hover .nav-logo {
    transform: scale(1.04);
}

.logo {
    color: #fff;
    font-size: 1.5rem;
    font-weight: bold;
    letter-spacing: 2px;
}

.logo span {
    color: var(--wood);
}

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

.nav-links a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--wood);
}

/* ==========================================
   3. HERO SLIDER SECTION (TAM EKRAN)
   ========================================== */
.hero {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    text-align: center;
    color: #fff;
    overflow: hidden;
    padding-bottom: 60px;
}

.hero-slider {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.hero-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center center;
    background-color: #0f172a;
    opacity: 0;
    transition: opacity 1.5s ease-in-out;
}

.hero-slide.active {
    opacity: 1;
}

.hero-content {
    position: relative;
    z-index: 3;
    max-width: 850px;
    padding: 0 20px;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.7);
}

.hero p {
    font-size: 1.25rem;
    max-width: 750px;
    margin: 0 auto 2rem auto;
    text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.7);
}

/* Butonlar */
.btn {
    padding: 12px 30px;
    background: var(--wood);
    color: #fff;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    transition: background 0.3s ease;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.btn:hover {
    background: #a66e3e;
}

.btn-whatsapp {
    background: #25d366;
    margin-left: 10px;
}

.btn-whatsapp:hover {
    background: #1eb954;
}

/* ==========================================
   4. GENEL KONTEYNER VE SEKSİYONLAR
   ========================================== */
.container {
    padding: 4rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.section-title {
    text-align: center;
    font-size: 2.2rem;
    color: var(--primary);
    margin-bottom: 2.5rem;
    position: relative;
}

.section-title::after {
    content: '';
    width: 60px;
    height: 3px;
    background: var(--wood);
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
}

/* 3. Section: Ayrıcalıklar */
#features {
    position: relative;
    z-index: 10;
    background-color: #fff;
    padding: 60px 20px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 25px;
}

.feature-card {
    background: #fff;
    padding: 25px;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-4px);
}

.feature-card i {
    font-size: 2.2rem;
    color: var(--accent);
    margin-bottom: 12px;
}

/* Tesis Detayları (Hakkında) */
.about-box {
    background: #fff;
    border-radius: 10px;
    padding: 3rem;
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
    align-items: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.about-img {
    flex: 1;
    min-width: 300px;
    border-radius: 8px;
    overflow: hidden;
}

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

.about-text {
    flex: 1;
    min-width: 300px;
}

.about-text h3 {
    color: var(--primary);
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.about-text ul {
    list-style: none;
    margin-top: 1rem;
}

.about-text ul li {
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.05rem;
}

.about-text ul li i {
    color: var(--accent);
}

/* ==========================================
   5. GALERİ VE VİDEO IZGARASI
   ========================================== */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.gallery-item {
    position: relative;
    border-radius: 8px;
    overflow: hidden;
    height: 260px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    cursor: pointer;
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.gallery-item:hover img {
    transform: scale(1.08);
}

.gallery-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.8));
    color: #fff;
    padding: 15px;
    font-size: 0.95rem;
    pointer-events: none;
}

.video-gallery-item video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    pointer-events: none;
}

.play-icon-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 3.5rem;
    color: rgba(255, 255, 255, 0.85);
    transition: transform 0.3s ease, color 0.3s ease;
    z-index: 2;
}

.video-gallery-item:hover .play-icon-overlay {
    transform: translate(-50%, -50%) scale(1.15);
    color: #fff;
}

/* ==========================================
   6. LIGHTBOX MODAL
   ========================================== */
.lightbox-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    justify-content: center;
    align-items: center;
    flex-direction: column;
}

.lightbox-modal.active {
    display: flex;
}

.lightbox-content {
    max-width: 90%;
    max-height: 80vh;
    border-radius: 6px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
}

.lightbox-caption {
    color: #fff;
    margin-top: 15px;
    font-size: 1.1rem;
    text-align: center;
}

.lightbox-close, .lightbox-prev, .lightbox-next {
    position: absolute;
    color: #fff;
    font-size: 2.5rem;
    cursor: pointer;
    transition: color 0.2s ease;
    user-select: none;
}

.lightbox-close {
    top: 20px;
    right: 30px;
}

.lightbox-prev {
    top: 50%;
    left: 20px;
    transform: translateY(-50%);
    padding: 15px;
}

.lightbox-next {
    top: 50%;
    right: 20px;
    transform: translateY(-50%);
    padding: 15px;
}

.lightbox-close:hover, .lightbox-prev:hover, .lightbox-next:hover {
    color: var(--wood);
}

/* ==========================================
   7. FOOTER VE SOSYAL MEDYA
   ========================================== */
footer {
    background: var(--primary);
    color: #fff;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
}

.social-links {
    margin-top: 15px;
    display: flex;
    justify-content: center;
    gap: 20px;
}

.social-links a {
    color: #fff;
    font-size: 1.8rem;
    transition: color 0.3s ease, transform 0.3s ease;
}

.social-links a:hover {
    color: var(--wood);
    transform: translateY(-3px);
}

/* ==========================================
   8. MOBİL EKRAN UYURUMLULUĞU (RESPONSIVE)
   ========================================== */
@media (max-width: 768px) {
    nav {
        padding: 0 15px;
    }

    .nav-links {
        display: none; /* İsteğe göre mobil menü butonu eklenebilir */
    }

    .hero {
        height: 100vh;
        padding-bottom: 40px;
    }

    .hero h1 {
        font-size: 1.6rem;
        line-height: 1.3;
        margin-bottom: 10px;
    }

    .hero p {
        font-size: 0.95rem;
        margin-bottom: 20px;
    }

    .hero-content div {
        display: flex;
        flex-direction: column;
        gap: 10px;
        align-items: center;
    }

    .hero-content .btn {
        width: 100%;
        max-width: 280px;
        padding: 12px 20px;
        font-size: 0.95rem;
        margin-left: 0;
    }

    .about-box {
        padding: 1.5rem;
    }

    .lightbox-prev {
        left: 5px;
    }

    .lightbox-next {
        right: 5px;
    }
}