/* ============================================
   KOCAELI GÜVEN NAKLİYAT - MODERN CSS
   Mobile-First Responsive Design
   ============================================ */

/* CSS Variables for Easy Customization */
:root {
    /* Colors - Professional Blue Theme */
    --primary-blue: #1e40af;
    --primary-blue-light: #3b82f6;
    --primary-blue-dark: #1e3a8a;
    --accent-orange: #f97316;
    --accent-orange-hover: #ea580c;
    
    /* Neutral Colors */
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-600: #4b5563;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Typography */
    --font-primary: 'Open Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-heading: 'Open Sans', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 300ms ease-in-out;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Container */
    --container-max: 1200px;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

a:hover {
    color: var(--primary-blue-dark);
}

ul {
    list-style: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
    margin-bottom: var(--spacing-md);
}

h1 { font-size: clamp(1.75rem, 5vw, 2.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: var(--spacing-sm);
    color: var(--gray-600);
}

/* ============================================
   LAYOUT & UTILITIES
   ============================================ */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.section {
    padding: var(--spacing-xl) 0;
}

.section-lg {
    padding: var(--spacing-2xl) 0;
}

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

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

/* ============================================
   HEADER & NAVIGATION
   ============================================ */
.header {
    background: var(--white);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-blue);
}

.logo-icon {
    font-size: 1.75rem;
}

/* Mobile Menu Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: var(--spacing-xs);
    z-index: 1001;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--gray-800);
    border-radius: 2px;
    transition: var(--transition-base);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Navigation Menu */
.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.nav-menu a {
    color: var(--gray-800);
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-blue);
    transition: width var(--transition-base);
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

/* CTA Button in Nav */
.nav-cta {
    background: var(--accent-orange);
    color: var(--white) !important;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.nav-cta:hover {
    background: var(--accent-orange-hover);
}

.nav-cta::after {
    display: none;
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--primary-blue-dark) 100%);
    color: var(--white);
    padding: var(--spacing-2xl) 0;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 700px;
}

.hero h1 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.hero p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 0.875rem 2rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    cursor: pointer;
    text-align: center;
}

.btn-primary {
    background: var(--accent-orange);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background: var(--accent-orange-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--white);
    color: var(--primary-blue);
    border: 2px solid var(--primary-blue);
}

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

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

.btn-white:hover {
    background: var(--gray-100);
}

/* ============================================
   CARDS & SERVICES
   ============================================ */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.service-card {
    background: var(--white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid var(--gray-200);
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-blue-light);
}

.service-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-blue-light), var(--primary-blue));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    margin-bottom: var(--spacing-md);
}

.service-card h3 {
    color: var(--gray-900);
    margin-bottom: var(--spacing-sm);
}

.service-card p {
    color: var(--gray-600);
    margin-bottom: var(--spacing-md);
}

/* ============================================
   FEATURES & BENEFITS
   ============================================ */
.features-list {
    display: grid;
    gap: var(--spacing-md);
}

.feature-item {
    display: flex;
    align-items: start;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--gray-50);
    border-radius: var(--radius-md);
    transition: var(--transition-base);
}

.feature-item:hover {
    background: var(--white);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 40px;
    height: 40px;
    background: var(--primary-blue);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1.25rem;
}

.feature-content h4 {
    margin-bottom: var(--spacing-xs);
}

/* ============================================
   TESTIMONIALS
   ============================================ */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.testimonial-card {
    background: var(--white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border-left: 4px solid var(--primary-blue);
}

.testimonial-text {
    font-style: italic;
    color: var(--gray-600);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.author-avatar {
    width: 50px;
    height: 50px;
    background: var(--gray-200);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    color: var(--primary-blue);
}

.author-info h5 {
    margin-bottom: 0;
    font-size: 1rem;
}

.author-info .rating {
    color: var(--accent-orange);
}

/* ============================================
   STATS SECTION
   ============================================ */
.stats-section {
    background: var(--primary-blue);
    color: var(--white);
    padding: var(--spacing-xl) 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    text-align: center;
}

.stat-item h3 {
    color: var(--white);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-xs);
}

.stat-item p {
    color: rgba(255, 255, 255, 0.9);
}

/* ============================================
   CTA SECTION
   ============================================ */
.cta-section {
    background: linear-gradient(135deg, var(--primary-blue-light) 0%, var(--primary-blue-dark) 100%);
    color: var(--white);
    padding: var(--spacing-2xl) 0;
    text-align: center;
}

.cta-section h2 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.cta-section p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ============================================
   CONTACT FORM
   ============================================ */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--gray-800);
}

.form-control {
    width: 100%;
    padding: 0.875rem;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.1);
}

textarea.form-control {
    min-height: 150px;
    resize: vertical;
}

.contact-info-card {
    background: var(--gray-50);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
}

.contact-info-card h4 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.contact-info-card .icon {
    color: var(--primary-blue);
    font-size: 1.5rem;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    background: var(--gray-900);
    color: var(--gray-300);
    padding-top: var(--spacing-2xl);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-col h4 {
    color: var(--white);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
}

.footer-col ul li {
    margin-bottom: var(--spacing-xs);
}

.footer-col a {
    color: var(--gray-300);
    transition: color var(--transition-fast);
}

.footer-col a:hover {
    color: var(--white);
}

.social-links {
    display: flex;
    gap: var(--spacing-sm);
}

.social-link {
    width: 40px;
    height: 40px;
    background: var(--gray-800);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
}

.social-link:hover {
    background: var(--primary-blue);
    transform: translateY(-2px);
}

.footer-bottom {
    border-top: 1px solid var(--gray-800);
    padding: var(--spacing-lg) 0;
    text-align: center;
}

/* ============================================
   BREADCRUMB
   ============================================ */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) 0;
    font-size: 0.875rem;
    color: var(--gray-600);
}

.breadcrumb a {
    color: var(--primary-blue);
}

.breadcrumb span {
    color: var(--gray-400);
}

/* ============================================
   PAGE HEADER
   ============================================ */
.page-header {
    background: linear-gradient(135deg, var(--primary-blue-light) 0%, var(--primary-blue-dark) 100%);
    color: var(--white);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.page-header h1 {
    color: var(--white);
}

.page-header p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
}

/* ============================================
   IMAGE GALLERY
   ============================================ */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--spacing-md);
}

.gallery-item {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
}

.gallery-item:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-xl);
}

.gallery-item img {
    width: 100%;
    height: 250px;
    object-fit: cover;
}

/* ============================================
   LOADING SPINNER
   ============================================ */
.loading-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary-blue);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================
   RESPONSIVE - MOBILE FIRST
   ============================================ */

/* Tablet (768px and up) */
@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--white);
        flex-direction: column;
        align-items: flex-start;
        padding: 5rem var(--spacing-lg);
        box-shadow: var(--shadow-xl);
        transition: right var(--transition-base);
        gap: var(--spacing-sm);
    }
    
    .nav-menu.active {
        right: 0;
    }
    
    .nav-menu a {
        width: 100%;
        padding: var(--spacing-sm) 0;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Mobile (480px and down) */
@media (max-width: 480px) {
    :root {
        --spacing-xl: 2rem;
        --spacing-2xl: 2.5rem;
    }
    
    .gallery-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.hidden {
    display: none !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Lazy Loading Images */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s;
}

img[loading="lazy"].loaded {
    opacity: 1;
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .nav-toggle,
    .btn {
        display: none;
    }
}