:root {
    /* Light Theme Variables */
    --primary-color: #2563eb; /* Royal Blue */
    --primary-dark: #1e40af;
    --secondary-color: #06b6d4; /* Cyan */
    --accent-color: #f59e0b; /* Amber for highlights */
    
    --bg-color: #ffffff;
    --bg-alt: #f8fafc;
    --text-color: #1e293b;
    --text-light: #64748b;
    
    --card-bg: #ffffff;
    --card-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.1);
    --card-border: 1px solid rgba(226, 232, 240, 0.8);
    
    --nav-bg: rgba(255, 255, 255, 0.9);
    --nav-border: 1px solid rgba(226, 232, 240, 0.6);
    
    --transition: all 0.3s ease;
    --radius: 16px;
}

[data-theme="dark"] {
    /* Dark Theme Variables */
    --primary-color: #3b82f6;
    --primary-dark: #60a5fa;
    --secondary-color: #22d3ee;
    
    --bg-color: #0f172a;
    --bg-alt: #1e293b;
    --text-color: #f1f5f9;
    --text-light: #94a3b8;
    
    --card-bg: #1e293b;
    --card-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
    --card-border: 1px solid rgba(51, 65, 85, 0.5);
    
    --nav-bg: rgba(15, 23, 42, 0.9);
    --nav-border: 1px solid rgba(51, 65, 85, 0.6);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
    overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 3.5rem;
    letter-spacing: -1px;
}

h2.section-title {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    position: relative;
    display: inline-block;
}

h2.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 60px;
    height: 4px;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.center {
    text-align: center;
}

.center::after {
    left: 50%;
    transform: translateX(-50%);
}

p {
    margin-bottom: 1.5rem;
    color: var(--text-light);
}

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

ul {
    list-style: none;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--text-color);
    border: 2px solid var(--primary-color);
}

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

.btn-block {
    display: block;
    width: 100%;
}

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

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: blur(10px);
    border-bottom: var(--nav-border);
    padding: 1rem 0;
    transition: var(--transition);
}

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

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

.logo .highlight {
    color: var(--primary-color);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-weight: 500;
    color: var(--text-color);
    font-size: 0.95rem;
}

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link.btn-primary {
    color: white;
    padding: 8px 24px;
}

#theme-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 5px;
    transition: var(--transition);
}

#theme-toggle:hover {
    transform: rotate(15deg);
    color: var(--primary-color);
}

.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    background-color: var(--text-color);
    transition: var(--transition);
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    top: 70px;
    left: 0;
    width: 100%;
    background: var(--bg-color);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    transform: translateY(-150%);
    transition: var(--transition);
    z-index: 999;
    border-bottom: var(--nav-border);
    text-align: center;
}

.mobile-menu.active {
    transform: translateY(0);
}

.mobile-link {
    font-size: 1.2rem;
    font-weight: 600;
}

/* Hero Section */
.hero {
    padding: 160px 0 100px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.badge {
    display: inline-block;
    padding: 8px 16px;
    background: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
}

.stats {
    display: flex;
    gap: 3rem;
    border-top: 1px solid var(--text-light);
    padding-top: 2rem;
    opacity: 0.8;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-color);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-light);
}

.hero-visual {
    position: relative;
    height: 500px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.blob-bg {
    position: absolute;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(37, 99, 235, 0.1) 0%, rgba(0,0,0,0) 70%);
    z-index: -1;
}

.math-illustration {
    position: relative;
    width: 100%;
    height: 100%;
}

.floating-icon {
    position: absolute;
    color: var(--primary-color);
    opacity: 0.1;
    animation: float 6s ease-in-out infinite;
}

.icon-1 { top: 10%; right: 10%; animation-delay: 0s; }
.icon-2 { bottom: 20%; left: 10%; animation-delay: 2s; }
.icon-3 { top: 40%; left: 40%; animation-delay: 4s; font-size: 2rem; }

.glass-card {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 2rem;
    border-radius: 24px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    width: 300px;
    height: 300px;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1;
}

[data-theme="dark"] .glass-card {
    background: rgba(30, 41, 59, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.card-content {
    text-align: center;
    color: var(--text-color);
}

.card-content i {
    font-size: 4rem;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.card-content span {
    display: block;
    font-size: 1.2rem;
    font-weight: 600;
}

@keyframes float {
    0% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(5deg); }
    100% { transform: translateY(0px) rotate(0deg); }
}

.about {
    padding: 100px 0;
    background-color: var(--bg-alt); /* veya istediğiniz renk */
}

.about-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-image {
    position: relative;
    /* Fotoğrafın etrafındaki süslemelerin taşmasını önlemek veya düzgün durmasını sağlamak için eklenebilir. Sizin tasarımınıza göre değişir. */
}

.image-frame {
    width: 100%;
    aspect-ratio: 1; /* Kare bir çerçeve sağlar */
    border-radius: 24px;
    overflow: hidden; /* Dışarı taşan kısımları gizler, çok önemli! */
    box-shadow: var(--card-shadow);
    /* Çerçeve rengi efekti için padding ve arka plan */
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    padding: 10px; /* Bu 10px, fotoğrafın etrafında bir kenarlık gibi görünecektir */
}

/* YENİ EKLENEN KISIM: Fotoğrafı çerçevenin içine oturtan ayar */
.profile-photo {
    width: 100%;
    height: 100%;
    object-fit: cover; /* Fotoğrafın en boy oranını koruyarak kutuyu doldurmasını sağlar. Taşan kısımlar kırpılır. */
    border-radius: 14px; /* image-frame'in padding'i olduğu için, içteki fotoğrafın köşe yuvarlaklığı çerçeveninkinden (24px - 10px) biraz az olmalı ki uyumlu dursun. */
    display: block; /* Alt kısımdaki boşluğu kaldırır */
}

.placeholder-profile {
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    border-radius: 18px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    font-weight: 700;
    color: var(--primary-color);
}


.features-list {
    margin-top: 2rem;
}

.features-list li {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    font-weight: 500;
}

.features-list li i {
    color: var(--secondary-color);
    background: rgba(6, 182, 212, 0.1);
    padding: 8px;
    border-radius: 50%;
    font-size: 0.8rem;
}

/* Levels Section */
.levels {
    padding: 100px 0;
}

.section-subtitle {
    margin-bottom: 4rem;
    font-size: 1.1rem;
}

.levels-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.level-card {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: var(--radius);
    border: var(--card-border);
    box-shadow: var(--card-shadow);
    transition: var(--transition);
}

.level-card:hover {
    transform: translateY(-10px);
    border-color: var(--primary-color);
}

.icon-box {
    width: 60px;
    height: 60px;
    border-radius: 16px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: white;
}

.color-1 { background: #f59e0b; }
.color-2 { background: #ef4444; }
.color-3 { background: #8b5cf6; }
.color-4 { background: #10b981; }

.level-card h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.level-features {
    margin-top: 1.5rem;
    border-top: 1px solid var(--nav-border);
    padding-top: 1.5rem;
}

.level-features li {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.2rem;
}

.level-features li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* System Section */
.system {
    padding: 100px 0;
    background-color: var(--bg-alt);
}

.system-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
    margin-top: 4rem;
}

.step {
    position: relative;
    padding: 2rem;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--card-shadow);
    text-align: center;
    transition: var(--transition);
}

.step:hover {
    transform: scale(1.05);
}

.step-number {
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: 700;
    font-size: 1.2rem;
    margin: 0 auto 1.5rem;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

/* Reviews Section */
.reviews {
    padding: 100px 0;
}

.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 4rem;
}

.review-card {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: var(--radius);
    border: var(--card-border);
    box-shadow: var(--card-shadow);
}

.stars {
    color: #f59e0b;
    margin-bottom: 1rem;
}

.reviewer {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 1.5rem;
}

.reviewer-info h4 {
    font-size: 1rem;
    margin-bottom: 0;
}

.reviewer-info span {
    font-size: 0.85rem;
    color: var(--text-light);
}

/* Contact Section */
.contact {
    padding: 100px 0;
    background-color: var(--bg-alt);
}

.contact-container {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 4rem;
    background: var(--card-bg);
    padding: 3rem;
    border-radius: 24px;
    box-shadow: var(--card-shadow);
}

.info-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 2rem;
}

.info-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    background: rgba(37, 99, 235, 0.1);
    padding: 12px;
    border-radius: 12px;
}

.info-item h4 {
    font-size: 1.1rem;
    margin-bottom: 0.2rem;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

.social-links a {
    width: 45px;
    height: 45px;
    background: var(--bg-color);
    border: 1px solid var(--nav-border);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 16px;
    background: var(--bg-color);
    border: 1px solid var(--nav-border);
    border-radius: 12px;
    font-family: inherit;
    color: var(--text-color);
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

/* Footer */
footer {
    padding: 2rem 0;
    background: var(--bg-color);
    border-top: var(--nav-border);
    font-size: 0.9rem;
    color: var(--text-light);
}

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

.footer-links {
    display: flex;
    gap: 2rem;
}

/* WhatsApp Button */
.whatsapp-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 60px;
    height: 60px;
    background-color: #25d366;
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    box-shadow: 0 4px 15px rgba(37, 211, 102, 0.4);
    z-index: 1000;
    transition: var(--transition);
    animation: pulse 2s infinite;
}

.whatsapp-btn:hover {
    transform: scale(1.1);
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(37, 211, 102, 0.7); }
    70% { box-shadow: 0 0 0 15px rgba(37, 211, 102, 0); }
    100% { box-shadow: 0 0 0 0 rgba(37, 211, 102, 0); }
}

/* Responsive */
@media (max-width: 968px) {
    h1 { font-size: 2.5rem; }
    
    .hero-container,
    .about-container,
    .contact-container {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .hero {
        text-align: center;
        padding-top: 120px;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .stats {
        justify-content: center;
    }
    
    .hero-visual {
        height: 400px;
    }
    
    .nav-links {
        display: none;
    }
    
    .hamburger {
        display: block;
    }
    
    .contact-container {
        padding: 2rem;
    }
}

@media (max-width: 576px) {
    h1 { font-size: 2rem; }
    
    .stats {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .footer-container {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* Scroll Reveal Animation */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}