/* ============================================
   Du Nord Logistics - Main Stylesheet
   ============================================ */

/* CSS Variables - Color Palette & Typography */
:root {
  /* Primary - Warm Blues */
  --color-primary: #2B6CB0;
  --color-primary-dark: #1A4971;
  --color-primary-light: #4A9BD9;

  /* Secondary - Warm Neutrals */
  --color-warm-white: #FAFAF8;
  --color-warm-gray: #6B7280;
  --color-charcoal: #1F2937;

  /* Accents */
  --color-accent: #F59E0B;
  --color-success: #10B981;
  --color-error: #EF4444;

  /* Typography */
  --font-heading: 'Source Sans Pro', 'Segoe UI', sans-serif;
  --font-body: 'Open Sans', 'Helvetica Neue', Arial, sans-serif;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 3rem;
  --spacing-xl: 4rem;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);

  /* Transitions */
  --transition-fast: 200ms ease;
  --transition-normal: 300ms ease;
}

/* ============================================
   Reset & Base Styles
   ============================================ */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-charcoal);
  background-color: var(--color-warm-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

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

a:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* ============================================
   Typography
   ============================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.2;
  color: var(--color-primary-dark);
  margin-bottom: var(--spacing-sm);
}

h1 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: 2rem;
}

h3 {
  font-size: 1.5rem;
}

h4 {
  font-size: 1.25rem;
}

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

strong {
  font-weight: 600;
  color: var(--color-charcoal);
}

/* ============================================
   Layout Components
   ============================================ */

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

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

.section--alt {
  background-color: #ffffff;
}

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

/* Skip to content link for accessibility */
.skip-to-content {
  position: absolute;
  top: -100px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--spacing-sm);
  z-index: 100;
  text-decoration: none;
}

.skip-to-content:focus {
  top: 0;
}

/* ============================================
   Navigation
   ============================================ */

.header {
  background-color: #ffffff;
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 50;
}

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

.nav__logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary-dark);
}

.nav__logo span {
  color: var(--color-primary);
}

.nav__menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-md);
  align-items: center;
}

.nav__link {
  font-weight: 500;
  color: var(--color-charcoal);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.nav__link:hover {
  color: var(--color-primary);
  background-color: rgba(43, 108, 176, 0.1);
}

.nav__link--active {
  color: var(--color-primary);
  font-weight: 600;
}

.nav__toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--color-primary-dark);
  cursor: pointer;
  padding: var(--spacing-xs);
}

/* Mobile Navigation */
@media (max-width: 768px) {
  .nav__toggle {
    display: block;
  }

  .nav__menu {
    position: fixed;
    top: 60px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 60px);
    background-color: #ffffff;
    flex-direction: column;
    padding: var(--spacing-md);
    gap: var(--spacing-sm);
    transition: left var(--transition-normal);
    box-shadow: var(--shadow-lg);
  }

  .nav__menu--open {
    left: 0;
  }

  .nav__link {
    width: 100%;
    text-align: center;
    padding: var(--spacing-sm);
  }
}

/* ============================================
   Buttons
   ============================================ */

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  text-align: center;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.btn:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

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

.btn--primary:hover {
  background-color: var(--color-primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

.btn--accent:hover {
  background-color: #d97706;
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

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

.btn--large {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: white;
  padding: var(--spacing-xl) 0;
  text-align: center;
}

.hero__title {
  color: white;
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
  line-height: 1.2;
}

.hero__subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--spacing-md);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero__cta {
  margin-top: var(--spacing-md);
}

@media (min-width: 768px) {
  .hero {
    padding: 5rem 0;
  }

  .hero__title {
    font-size: 3.5rem;
  }

  .hero__subtitle {
    font-size: 1.5rem;
  }
}

/* ============================================
   Cards
   ============================================ */

.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

@media (min-width: 768px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.card {
  background-color: white;
  border-radius: var(--radius-sm);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card__icon {
  font-size: 2.5rem;
  color: var(--color-primary);
  margin-bottom: var(--spacing-sm);
}

.card__title {
  font-size: 1.5rem;
  color: var(--color-primary-dark);
  margin-bottom: var(--spacing-sm);
}

.card__description {
  color: var(--color-warm-gray);
  margin-bottom: var(--spacing-sm);
}

.card__list {
  list-style: none;
  margin: var(--spacing-sm) 0;
}

.card__list li {
  padding: var(--spacing-xs) 0;
  color: var(--color-warm-gray);
  position: relative;
  padding-left: var(--spacing-md);
}

.card__list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--color-success);
  font-weight: bold;
}

/* ============================================
   Forms
   ============================================ */

.form {
  max-width: 600px;
  margin: 0 auto;
}

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

.form__label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
  color: var(--color-charcoal);
}

.form__label--required::after {
  content: " *";
  color: var(--color-error);
}

.form__input,
.form__textarea,
.form__select {
  width: 100%;
  padding: 0.75rem;
  font-family: var(--font-body);
  font-size: 1rem;
  border: 2px solid #D1D5DB;
  border-radius: var(--radius-sm);
  transition: border-color var(--transition-fast);
}

.form__input:focus,
.form__textarea:focus,
.form__select:focus {
  outline: none;
  border-color: var(--color-primary);
}

.form__input--error,
.form__textarea--error,
.form__select--error {
  border-color: var(--color-error);
}

.form__textarea {
  min-height: 150px;
  resize: vertical;
}

.form__error {
  color: var(--color-error);
  font-size: 0.875rem;
  margin-top: var(--spacing-xs);
  display: none;
}

.form__error--visible {
  display: block;
}

.form__success {
  background-color: #D1FAE5;
  color: #065F46;
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing-md);
  display: none;
}

.form__success--visible {
  display: block;
}

/* Honeypot field - hidden from users, catches bots */
.form__honeypot {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

/* ============================================
   Two Column Layout (for contact page)
   ============================================ */

.two-column {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-lg);
  align-items: start;
}

@media (min-width: 768px) {
  .two-column {
    grid-template-columns: 2fr 1fr;
  }
}

.contact-info {
  background-color: white;
  padding: var(--spacing-md);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
}

.contact-info__item {
  margin-bottom: var(--spacing-md);
}

.contact-info__label {
  font-weight: 600;
  color: var(--color-primary-dark);
  margin-bottom: var(--spacing-xs);
}

.contact-info__value {
  color: var(--color-warm-gray);
}

/* ============================================
   Footer
   ============================================ */

.footer {
  background-color: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.9);
  padding: var(--spacing-lg) 0 var(--spacing-md);
  margin-top: var(--spacing-xl);
}

.footer__content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

@media (min-width: 768px) {
  .footer__content {
    grid-template-columns: 2fr 1fr 1fr;
  }
}

.footer__section-title {
  color: white;
  font-size: 1.125rem;
  margin-bottom: var(--spacing-sm);
}

.footer__text {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.9rem;
}

.footer__links {
  list-style: none;
}

.footer__link {
  color: rgba(255, 255, 255, 0.8);
  padding: var(--spacing-xs) 0;
  display: block;
  transition: color var(--transition-fast);
}

.footer__link:hover {
  color: white;
}

.footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding-top: var(--spacing-md);
  text-align: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.875rem;
}

/* ============================================
   Utility Classes
   ============================================ */

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }

.hidden {
  display: none;
}

.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;
}

/* ============================================
   Service Detail Page Styles
   ============================================ */

.service-detail {
  background-color: white;
  padding: var(--spacing-lg);
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing-md);
  box-shadow: var(--shadow-sm);
}

.service-detail__header {
  border-bottom: 3px solid var(--color-primary);
  padding-bottom: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.service-detail__title {
  color: var(--color-primary-dark);
  margin-bottom: var(--spacing-xs);
}

.service-detail__subtitle {
  color: var(--color-warm-gray);
  font-size: 1.125rem;
}

/* ============================================
   About Page Styles
   ============================================ */

.about-section {
  margin-bottom: var(--spacing-lg);
}

.values-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

@media (min-width: 768px) {
  .values-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

.value-card__title {
  color: var(--color-primary-dark);
  margin-bottom: var(--spacing-sm);
}

/* ============================================
   Loading States
   ============================================ */

.btn--loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}

.btn--loading::after {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  top: 50%;
  left: 50%;
  margin-left: -8px;
  margin-top: -8px;
  border: 2px solid transparent;
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

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