/*
 * Global styles for the ArkVision website. The design uses a dark maritime
 * palette inspired by the colours of the ocean and sky. Generous whitespace,
 * soft gradients and rounded corners give the site a clean, modern feel.
 * Responsive layouts are achieved using flexbox and CSS grid, while
 * variables make it easy to adjust colours across the entire site.
 */

/* CSS variables for colours and sizing */
:root {
  --primary: #0a1931; /* deep navy */
  --secondary: #10284e; /* dark blue */
  --accent: #009fdc; /* bright teal */
  --light: #f6f8fa; /* off‑white */
  --muted: #ccd4e0; /* light blue grey */
  --text-light: #eef3f8;
  --text-dark: #121f3d;
  --max-width: 1100px;
  --transition-speed: 0.3s;
  --border-radius: 8px;
}

/* Reset & base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--primary);
  color: var(--text-light);
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition-speed) ease;
}
a:hover,
a:focus {
  /* lighten accent colour manually since CSS functions are not available */
  color: #32b8f6;
}

/* Utility classes */
.container {
  width: 90%;
  max-width: var(--max-width);
  margin: 0 auto;
}
.btn {
  display: inline-block;
  padding: 0.6rem 1.4rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  transition: background-color var(--transition-speed) ease;
}
.btn-primary {
  background: var(--accent);
  color: var(--text-dark);
}
.btn-primary:hover {
  background: #00b3ff;
}
.btn-secondary {
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
}
.btn-secondary:hover {
  background: var(--accent);
  color: var(--text-dark);
}
.btn-link {
  display: inline-block;
  margin-top: 0.5rem;
  color: var(--accent);
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-speed);
}
.btn-link:hover {
  border-color: var(--accent);
}
.small {
  padding: 0.4rem 1rem;
  font-size: 0.875rem;
}

/* Header and navigation */
.site-header {
  background: var(--secondary);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}
.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}
.logo a {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
}
.nav-menu ul {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 2rem;
}
.nav-menu a {
  color: var(--text-light);
  font-weight: 500;
  position: relative;
  padding: 0.25rem 0;
  transition: color var(--transition-speed) ease;
}
.nav-menu a.active,
.nav-menu a:hover {
  color: var(--accent);
}
/* underline effect on hover */
.nav-menu a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -4px;
  height: 2px;
  width: 0;
  background: var(--accent);
  transition: width var(--transition-speed) ease;
}
.nav-menu a:hover::after,
.nav-menu a.active::after {
  width: 100%;
}

/* Mobile navigation */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 26px;
  height: 20px;
  cursor: pointer;
  border: none;
  background: none;
}
.nav-toggle .bar {
  height: 3px;
  width: 100%;
  background: var(--accent);
  border-radius: 2px;
}

/* Hero section */
.hero {
  position: relative;
  height: 70vh;
  overflow: hidden;
}
.hero-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-position: center;
  opacity: 0;
  transition: opacity 1s ease-in-out;
  display: flex;
  align-items: center;
  justify-content: center;
}
.hero-slide.active {
  opacity: 1;
}
.hero-content {
  text-align: center;
  background: rgba(0, 0, 0, 0.45);
  padding: 1.5rem 2rem;
  border-radius: var(--border-radius);
}
.hero-content h1 {
  font-size: 2.2rem;
  margin-bottom: 0.5rem;
}
.hero-content p {
  margin-bottom: 1rem;
  font-size: 1.1rem;
  color: var(--muted);
}
.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
}
.hero-pagination {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.6rem;
}
.hero-pagination button {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: none;
  background: rgba(255, 255, 255, 0.4);
  cursor: pointer;
  transition: background var(--transition-speed);
}
.hero-pagination button.active,
.hero-pagination button:hover {
  background: var(--accent);
}

/* Page hero (for other pages) */
.page-hero {
  position: relative;
  height: 40vh;
  background-size: cover;
  background-position: center;
  display: flex;
  align-items: center;
  justify-content: center;
}
.page-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
}
.page-hero-content {
  position: relative;
  text-align: center;
  z-index: 1;
}
.page-hero-content h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}
.page-hero-content p {
  font-size: 1rem;
  color: var(--muted);
}

/* Section base styling */
section {
  padding: 3rem 0;
}
.section-intro {
  text-align: center;
  margin-bottom: 2rem;
}
.section-intro h2 {
  font-size: 1.8rem;
  margin-bottom: 0.5rem;
}
.section-intro p {
  color: var(--muted);
  font-size: 1rem;
}

/* About preview */
.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}
.about-card {
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
  transition: transform var(--transition-speed) ease;
}
.about-card:hover {
  transform: translateY(-6px);
}
.about-card h3 {
  margin-bottom: 0.5rem;
  font-size: 1.2rem;
  color: var(--accent);
}
.about-card p {
  color: var(--muted);
  font-size: 0.95rem;
}

/* Products preview cards on home */
.product-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}
.product-card {
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  text-align: center;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
  transition: transform var(--transition-speed) ease;
}
.product-card:hover {
  transform: translateY(-6px);
}
.product-icon {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--text-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1rem;
  font-weight: 700;
  font-size: 1.2rem;
}
.product-card h3 {
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
  color: var(--accent);
}
.product-card p {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.center-btn {
  margin-top: 2rem;
  text-align: center;
}

/* Footer */
.site-footer {
  background: var(--secondary);
  color: var(--muted);
  padding: 2rem 0 0.5rem;
  margin-top: 3rem;
}
.footer-inner {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-bottom: 1.5rem;
}
.site-footer h4 {
  margin-bottom: 0.5rem;
  color: var(--accent);
}
.site-footer ul {
  list-style: none;
  color: var(--muted);
}
.site-footer li {
  margin-bottom: 0.5rem;
}
.footer-bottom {
  text-align: center;
  font-size: 0.8rem;
  color: var(--muted);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 0.5rem;
}

/* About page specifics */
.story-section p {
  margin-bottom: 1rem;
  color: var(--muted);
}
.mvv-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}
.mvv-card {
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
}
.mvv-card h3 {
  margin-bottom: 0.5rem;
  color: var(--accent);
}
.mvv-card p,
.mvv-card li {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
}
.values-list {
  list-style: none;
  padding-left: 0;
}
.values-list li strong {
  color: var(--text-light);
}

/* Timeline */
.timeline {
  position: relative;
  margin-top: 2rem;
  padding-left: 40px;
  border-left: 2px solid var(--accent);
}
.timeline-item {
  position: relative;
  margin-bottom: 2rem;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: -11px;
  top: 4px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent);
}
.timeline-year {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 0.3rem;
}
.timeline-content h4 {
  margin-bottom: 0.3rem;
  font-size: 1.1rem;
  color: var(--text-light);
}
.timeline-content p {
  color: var(--muted);
  font-size: 0.9rem;
}

/* Products page */
.product-list-section {
  padding-top: 2rem;
}
.product-search {
  margin-bottom: 1.5rem;
  text-align: center;
}
#productSearch {
  width: 100%;
  max-width: 400px;
  padding: 0.6rem 1rem;
  border-radius: var(--border-radius);
  border: none;
  background: var(--secondary);
  color: var(--text-light);
  font-size: 1rem;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.25) inset;
}
#productSearch::placeholder {
  color: var(--muted);
}
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}
.product-item {
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
  transition: transform var(--transition-speed);
}
.product-item:hover {
  transform: translateY(-6px);
}
.product-item h3 {
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
  color: var(--accent);
}
.product-item p {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}
.product-item .btn {
  display: inline-block;
}

/* Contact page */
.contact-section {
  padding: 3rem 0;
}
.contact-wrapper {
  display: flex;
  gap: 3rem;
  flex-wrap: wrap;
}
.contact-info {
  flex: 1 1 300px;
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 2rem;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
}
.contact-info h2,
.contact-form h2 {
  margin-bottom: 0.8rem;
  font-size: 1.4rem;
  color: var(--accent);
}
.info-list {
  list-style: none;
  margin: 1rem 0;
}
.info-list li {
  margin-bottom: 0.7rem;
  font-size: 0.95rem;
  color: var(--muted);
}
.additional-info {
  font-size: 0.9rem;
  color: var(--muted);
}
.contact-form {
  flex: 1 1 300px;
  background: var(--secondary);
  border-radius: var(--border-radius);
  padding: 2rem;
  box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
}
.form-group {
  margin-bottom: 1rem;
}
.form-group label {
  display: block;
  margin-bottom: 0.3rem;
  color: var(--text-light);
  font-size: 0.95rem;
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.6rem 0.8rem;
  border-radius: var(--border-radius);
  border: none;
  background: var(--primary);
  color: var(--text-light);
  font-size: 0.95rem;
}
.form-group input:focus,
.form-group textarea:focus {
  outline: 2px solid var(--accent);
}
.form-group textarea {
  resize: vertical;
}
.form-group .error {
  color: #ff7b7b;
  font-size: 0.8rem;
  display: none;
  margin-top: 0.2rem;
}
.required {
  color: #ff7b7b;
  margin-left: 0.2rem;
}
.form-response {
  margin-top: 1rem;
  font-size: 0.95rem;
  color: var(--accent);
}

/* Responsive adjustments */
@media (max-width: 768px) {
  .nav-menu ul {
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--secondary);
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    padding: 1rem 0;
    transform: translateY(-100%);
    transition: transform var(--transition-speed);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
  }
  .nav-menu.open ul {
    transform: translateY(0);
  }
  .nav-toggle {
    display: flex;
  }
  .hero-content h1 {
    font-size: 1.6rem;
  }
  .hero-content p {
    font-size: 0.95rem;
  }
  .contact-wrapper {
    flex-direction: column;
  }
}