/* ===== CSS Variables ===== */
:root {
    /* Primary Colors */
    --primary-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a855f7 100%);
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;

    /* Secondary Colors */
    --secondary-color: #10b981;
    --secondary-dark: #059669;
    --secondary-light: #34d399;

    /* Dark Mode Colors */
    --bg-dark: #0f0f23;
    --bg-card: #1a1a2e;
    --bg-card-hover: #252542;
    --bg-input: #16162a;

    /* Text Colors */
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;

    /* Border Colors */
    --border-color: rgba(99, 102, 241, 0.2);
    --border-hover: rgba(99, 102, 241, 0.4);

    /* Glass Effect */
    --glass-bg: rgba(26, 26, 46, 0.8);
    --glass-border: rgba(255, 255, 255, 0.1);

    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.3);

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* ===== Reset & Base ===== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(ellipse at top left, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(139, 92, 246, 0.1) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ===== Typography ===== */
h1,
h2,
h3,
h4 {
    font-weight: 700;
    line-height: 1.3;
}

h1 {
    font-size: clamp(2rem, 5vw, 3rem);
}

h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
}

h3 {
    font-size: 1.25rem;
}

h4 {
    font-size: 1rem;
}

/* ===== Header & Navigation ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(15, 15, 35, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-icon {
    font-size: 1.5rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--spacing-xl);
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-primary);
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--primary-gradient);
    border-radius: 1px;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-sm);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

/* ===== Background Image Container ===== */
.background-image-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    overflow: hidden;
}

.background-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0;
    transition: opacity 0.8s ease-in-out;
}

.background-image.active {
    opacity: 1;
}

.background-image.universite {
    background-image: url('images/universite-bg.png');
}

.background-image.yurtdisi {
    background-image: url('images/yurtdisi-bg.png');
}

.background-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg,
            rgba(15, 15, 35, 0.85) 0%,
            rgba(15, 15, 35, 0.75) 30%,
            rgba(15, 15, 35, 0.9) 100%);
    z-index: -1;
    pointer-events: none;
}

/* ===== Hero Section ===== */
.hero {
    padding: 8rem 0 3rem;
    text-align: center;
    position: relative;
}

.hero-content h1 {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-md);
}

.hero-content p {
    color: var(--text-secondary);
    font-size: 1.125rem;
    max-width: 600px;
    margin: 0 auto;
}

/* ===== Calculator Tabs ===== */
.calculator-tabs {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    justify-content: center;
    flex-wrap: wrap;
}

.tab-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.tab-btn:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    color: var(--text-primary);
}

.tab-btn.active {
    background: var(--primary-gradient);
    border-color: transparent;
    color: var(--text-primary);
    box-shadow: var(--shadow-glow);
}

.tab-icon {
    font-size: 1.25rem;
}

/* ===== Calculator Panels ===== */
.calculator-panel {
    display: none;
    animation: fadeIn 0.3s ease;
}

.calculator-panel.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.calculator-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

/* ===== Cards ===== */
.card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    overflow: hidden;
    transition: all var(--transition-normal);
}

.card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-md);
}

.card-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--glass-border);
}

.card-header h2,
.card-header h3 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
}

.card-header .icon {
    font-size: 1.5rem;
}

.card-body {
    padding: var(--spacing-lg);
}

/* ===== Form Styles ===== */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%23a1a1aa' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10l-5 5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
}

.form-group select option {
    background: var(--bg-card);
    color: var(--text-primary);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-primary {
    background: var(--primary-gradient);
    color: var(--text-primary);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.btn-block {
    width: 100%;
}

.btn-icon {
    font-size: 1.25rem;
    transition: transform var(--transition-fast);
}

.btn:hover .btn-icon {
    transform: translateX(4px);
}

/* ===== Result Styles ===== */
.result-card {
    animation: slideUp 0.4s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-grid {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md);
    background: var(--bg-input);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

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

.result-value {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.result-total {
    background: var(--primary-gradient);
    border: none;
}

.result-total .result-label,
.result-total .result-value {
    color: var(--text-primary);
}

.result-total .result-value {
    font-size: 1.5rem;
}

/* ===== Info Card ===== */
.info-card {
    margin-top: var(--spacing-lg);
}

.info-card .card-header h3 {
    font-size: 1rem;
}

.info-card .card-body p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.info-list {
    list-style: none;
}

.info-list li {
    padding: var(--spacing-xs) 0;
    padding-left: var(--spacing-lg);
    position: relative;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.info-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

/* ===== Info Section ===== */
.info-section {
    margin-top: var(--spacing-2xl);
    padding: var(--spacing-2xl) 0;
}

.info-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.feature-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--border-hover);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.feature-card h3 {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg-card);
    border-top: 1px solid var(--glass-border);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-xl);
}

.footer-section h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.footer-section h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    font-size: 1rem;
}

.footer-section p {
    color: var(--text-secondary);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: var(--spacing-sm);
}

.footer-section ul a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-section ul a:hover {
    color: var(--text-primary);
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--glass-border);
    text-align: center;
    color: var(--text-muted);
}

/* ===== Responsive Design ===== */
@media (max-width: 992px) {
    .calculator-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero {
        padding-top: 6rem;
    }

    .tab-btn {
        flex: 1;
        justify-content: center;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }

    .calculator-tabs {
        flex-direction: column;
    }

    .tab-btn {
        width: 100%;
    }
}

/* ===== Ad Container Styles ===== */
.ad-section {
    padding: var(--spacing-lg) 0;
}

.ad-container {
    background: rgba(26, 26, 46, 0.6);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    overflow: hidden;
    min-height: 90px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.ad-banner {
    width: 100%;
}

.ad-container ins {
    width: 100%;
}

/* Ad placeholder for development */
.ad-container::before {
    content: 'Reklam Alanı';
    color: var(--text-muted);
    font-size: 0.85rem;
    opacity: 0.5;
}

.ad-container ins.adsbygoogle[data-ad-status="filled"]+.ad-container::before,
.ad-container:has(ins[data-ad-status="filled"])::before {
    display: none;
}

@media (max-width: 768px) {
    .ad-container {
        min-height: 60px;
        padding: var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .ad-section {
        padding: var(--spacing-md) 0;
    }
}