/*
 * Corporate Engineering Website - Main Stylesheet
 * Modern, professional design system for engineering services company
 * Pure CSS3 with custom properties for easy maintenance
 */

/* ========================================
   IMPORTS - Google Fonts
   ======================================== */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700&family=Inter:wght@400;500;600&display=swap');

/* ========================================
   CSS CUSTOM PROPERTIES (Design Tokens)
   ======================================== */
:root {
  /* Color Palette - Engineering Corporate Theme */
  --color-primary: #0A2463;        /* Deep Blue */
  --color-primary-light: #1E3A8A;  /* Lighter Blue */
  --color-primary-dark: #06182E;   /* Darker Blue */
  --color-secondary: #3E4C59;      /* Industrial Gray */
  --color-accent: #FB8500;         /* Engineering Orange */
  --color-accent-hover: #E07600;   /* Darker Orange */
  
  /* Neutral Colors */
  --color-white: #FFFFFF;
  --color-light: #F8F9FA;
  --color-light-gray: #E9ECEF;
  --color-medium-gray: #6C757D;
  --color-dark: #212529;
  --color-black: #000000;
  
  /* Semantic Colors */
  --color-success: #28A745;
  --color-error: #DC3545;
  --color-warning: #FFC107;
  --color-info: #17A2B8;
  
  /* Typography */
  --font-heading: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Font Sizes - Responsive Scale */
  --font-size-xs: 0.75rem;    /* 12px */
  --font-size-sm: 0.875rem;   /* 14px */
  --font-size-base: 1rem;     /* 16px */
  --font-size-lg: 1.125rem;   /* 18px */
  --font-size-xl: 1.25rem;    /* 20px */
  --font-size-2xl: 1.5rem;    /* 24px */
  --font-size-3xl: 1.875rem;  /* 30px */
  --font-size-4xl: 2.25rem;   /* 36px */
  --font-size-5xl: 3rem;      /* 48px */
  --font-size-6xl: 3.75rem;   /* 60px */
  
  /* Font Weights */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Line Heights */
  --line-height-tight: 1.2;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* Spacing Scale */
  --spacing-xs: 0.25rem;   /* 4px */
  --spacing-sm: 0.5rem;    /* 8px */
  --spacing-md: 1rem;      /* 16px */
  --spacing-lg: 1.5rem;    /* 24px */
  --spacing-xl: 2rem;      /* 32px */
  --spacing-2xl: 3rem;     /* 48px */
  --spacing-3xl: 4rem;     /* 64px */
  --spacing-4xl: 6rem;     /* 96px */
  --spacing-5xl: 8rem;     /* 128px */
  
  /* Container Widths */
  --container-xl: 1280px;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  /* 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), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index Layers */
  --z-sticky: 1020;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-normal);
  color: var(--color-dark);
  background-color: var(--color-white);
  overflow-x: hidden;
}

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

h1 {
  font-size: var(--font-size-5xl);
  margin-bottom: var(--spacing-lg);
}

h2 {
  font-size: var(--font-size-4xl);
}

h3 {
  font-size: var(--font-size-3xl);
}

h4 {
  font-size: var(--font-size-2xl);
}

h5 {
  font-size: var(--font-size-xl);
}

h6 {
  font-size: var(--font-size-lg);
}

p {
  margin-bottom: var(--spacing-md);
  color: var(--color-secondary);
}

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

a:hover {
  color: var(--color-accent);
}

strong, b {
  font-weight: var(--font-weight-semibold);
}

/* ========================================
   LAYOUT CONTAINERS
   ======================================== */
.container {
  width: 100%;
  max-width: var(--container-xl);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-lg);
  padding-right: var(--spacing-lg);
}

.section {
  padding-top: var(--spacing-4xl);
  padding-bottom: var(--spacing-4xl);
}

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

.header.scrolled {
  box-shadow: var(--shadow-md);
}

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

.navbar-brand {
  font-family: var(--font-heading);
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.navbar-brand span {
  color: var(--color-accent);
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  list-style: none;
}

.nav-link {
  font-weight: var(--font-weight-medium);
  color: var(--color-secondary);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
  background-color: var(--color-light);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: var(--spacing-md);
  right: var(--spacing-md);
  height: 2px;
  background-color: var(--color-accent);
}

/* Mobile Menu Toggle */
.navbar-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
}

.navbar-toggle span {
  display: block;
  width: 25px;
  height: 3px;
  background-color: var(--color-primary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-base);
}

/* ========================================
   HERO SECTION
   ======================================== */
.hero {
  position: relative;
  min-height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--color-white);
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.3;
  z-index: 0;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(10, 36, 99, 0.9) 0%, rgba(30, 58, 138, 0.85) 100%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  padding: var(--spacing-2xl) var(--spacing-lg);
  animation: fadeInUp 1s ease-out;
}

.hero-title {
  font-size: var(--font-size-6xl);
  color: var(--color-white);
  margin-bottom: var(--spacing-lg);
  line-height: 1.1;
}

.hero-subtitle {
  font-size: var(--font-size-xl);
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--spacing-2xl);
  font-weight: var(--font-weight-normal);
}

.hero-cta {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* ========================================
   BUTTONS
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-family: var(--font-heading);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  line-height: 1;
  text-align: center;
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
}

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

.btn:active {
  transform: translateY(0);
}

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

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

.btn-secondary {
  background-color: transparent;
  color: var(--color-white);
  border-color: var(--color-white);
}

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

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

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

.btn-lg {
  padding: var(--spacing-lg) var(--spacing-2xl);
  font-size: var(--font-size-lg);
}

/* ========================================
   CARDS
   ======================================== */
.card {
  background-color: var(--color-white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: all var(--transition-base);
  height: 100%;
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-2xl);
}

.card-img {
  width: 100%;
  height: 250px;
  opacity: 1 !important;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.card:hover .card-img {
  transform: scale(1.05);
}

.card-body {
  padding: var(--spacing-xl);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-title {
  font-size: var(--font-size-2xl);
  color: var(--color-primary);
  margin-bottom: var(--spacing-md);
}

.card-text {
  color: var(--color-secondary);
  margin-bottom: var(--spacing-lg);
  flex: 1;
}

.card-link {
  color: var(--color-accent);
  font-weight: var(--font-weight-semibold);
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  transition: gap var(--transition-base);
}

.card-link:hover {
  gap: var(--spacing-sm);
  color: var(--color-accent-hover);
}

/* ========================================
   GRID SYSTEM
   ======================================== */
.grid {
  display: grid;
  gap: var(--spacing-xl);
}

.grid-cols-1 {
  grid-template-columns: repeat(1, 1fr);
}

.grid-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

/* ========================================
   SECTIONS
   ======================================== */
.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto var(--spacing-3xl);
}

.section-title {
  font-size: var(--font-size-4xl);
  color: var(--color-primary);
  margin-bottom: var(--spacing-md);
}

.section-subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-secondary);
  font-weight: var(--font-weight-normal);
}

.bg-light {
  background-color: var(--color-light);
}

.bg-dark {
  background-color: var(--color-primary);
  color: var(--color-white);
}

.bg-dark .section-title,
.bg-dark h2,
.bg-dark h3 {
  color: var(--color-white);
}

.bg-dark .section-subtitle,
.bg-dark p {
  color: rgba(255, 255, 255, 0.85);
}

/* ========================================
   STATS / TRUST INDICATORS
   ======================================== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-2xl);
  text-align: center;
}

.stat-item {
  padding: var(--spacing-xl);
}

.stat-number {
  font-size: var(--font-size-5xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-accent);
  margin-bottom: var(--spacing-sm);
}

.stat-label {
  font-size: var(--font-size-lg);
  color: var(--color-white);
}

/* ========================================
   FOOTER
   ======================================== */
.footer {
  background-color: var(--color-primary);
  color: var(--color-white);
  padding-top: var(--spacing-3xl);
  padding-bottom: var(--spacing-xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
  color: var(--color-white);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
}

.footer-section p,
.footer-section a {
  color: rgba(255, 255, 255, 0.8);
  line-height: var(--line-height-relaxed);
}

.footer-section a:hover {
  color: var(--color-accent);
}

.footer-links {
  list-style: none;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding-top: var(--spacing-lg);
  text-align: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: var(--font-size-sm);
}

/* ========================================
   UTILITY CLASSES
   ======================================== */
.text-center {
  text-align: center;
}

.text-primary {
  color: var(--color-primary) !important;
}

.text-accent {
  color: var(--color-accent) !important;
}

.text-white {
  color: var(--color-white) !important;
}

.mb-0 { margin-bottom: 0; }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

/* ========================================
   ANIMATIONS
   ======================================== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

.fade-in-up {
  animation: fadeInUp 0.8s ease-out;
}

/* Lazy loading images */
/*img[data-src] {
  opacity: 0;
  transition: opacity var(--transition-slow);
}

img.loaded {
  opacity: 1;
}*/

/* ========================================
   BREADCRUMB
   ======================================== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  list-style: none;
  padding: var(--spacing-md) 0;
  font-size: var(--font-size-sm);
}

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

.breadcrumb-item + .breadcrumb-item::before {
  content: '/';
  color: var(--color-medium-gray);
}

.breadcrumb-item a {
  color: var(--color-medium-gray);
}

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

.breadcrumb-item.active {
  color: var(--color-dark);
}

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

.form-label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-dark);
}

.form-control {
  width: 100%;
  padding: var(--spacing-md);
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-dark);
  background-color: var(--color-white);
  border: 2px solid var(--color-light-gray);
  border-radius: var(--radius-md);
  transition: border-color var(--transition-base);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
}

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

.form-control.error {
  border-color: var(--color-error);
}

.form-error {
  color: var(--color-error);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-xs);
}


.navbar-brand.logo img {
    height: 40px;          /* Header yüksekliğine göre ayarla */
    width: auto;
    display: block;
}


.social-link a {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: inherit;
    text-decoration: none;
    transition: color 0.3s ease;
}

.social-link a i {
    font-size: 1.2rem;
}

.social-link a:hover {
    color: #E1306C; /* Instagram rengi */
}

.image-column {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}