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

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: #2c3e50;
  background-color: #f4f6f8;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

h1, h2, h3, h4 {
  font-weight: 700;
  color: #1a2a3a;
  line-height: 1.2;
}

h1 { font-size: 2.25rem; margin-bottom: 1rem; }
h2 { font-size: 1.75rem; margin-bottom: 0.75rem; }
h3 { font-size: 1.25rem; margin-bottom: 0.5rem; }

p {
  margin-bottom: 1rem;
}

a {
  color: #2980b9;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

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

/* ===========================
   Layout Utilities
   =========================== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
  width: 100%;
}

.section {
  padding: 3rem 0;
}

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

/* ===========================
   Navigation Bar
   =========================== */
header {
  background-color: #1a2a3a;
  color: #ffffff;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 0;
  padding-bottom: 0;
}

.logo a {
  color: #ffffff;
  font-size: 1.5rem;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 1px;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-img {
  width: 40px;
  height: 40px;
  border-radius: 4px;
}

.logo a:hover {
  text-decoration: none;
  color: #e0e0e0;
}

nav {
  display: flex;
  align-items: center;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 0.25rem;
}

.nav-links a {
  color: #cbd5e0;
  padding: 1rem 1.25rem;
  display: block;
  transition: color 0.2s, background-color 0.2s;
  font-weight: 500;
}

.nav-links a:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.1);
  text-decoration: none;
}

.nav-links a.active {
  color: #ffffff;
  border-bottom: 3px solid #3498db;
  background-color: rgba(255, 255, 255, 0.05);
}

/* Hamburger Button */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.75rem;
  flex-direction: column;
  gap: 5px;
}

.hamburger span {
  display: block;
  width: 25px;
  height: 3px;
  background-color: #ffffff;
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

/* ===========================
   Hero Section
   =========================== */
.hero {
  position: relative;
  background-color: #1a2a3a;
  color: #ffffff;
  text-align: center;
  overflow: hidden;
}

.hero img {
  width: 100%;
  height: 400px;
  object-fit: cover;
  opacity: 0.4;
}

.hero-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 1;
  width: 90%;
  max-width: 700px;
}

.hero h1 {
  color: #ffffff;
  font-size: 2.5rem;
  margin-bottom: 1rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.4);
}

.hero p {
  font-size: 1.15rem;
  margin-bottom: 1.5rem;
  color: #e0e0e0;
}

.btn {
  display: inline-block;
  padding: 0.75rem 2rem;
  border-radius: 4px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
  text-decoration: none;
  border: none;
}

.btn:hover {
  text-decoration: none;
}

.btn-primary {
  background-color: #3498db;
  color: #ffffff;
}

.btn-primary:hover {
  background-color: #2980b9;
  transform: translateY(-1px);
}

/* ===========================
   Company Introduction
   =========================== */
.intro {
  background-color: #ffffff;
}

.intro h2 {
  text-align: center;
}

.intro p {
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
  color: #4a5568;
  font-size: 1.05rem;
}

/* ===========================
   Product Card Grid
   =========================== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

/* ===========================
   Product Card
   =========================== */
.product-card {
  background-color: #ffffff;
  border-radius: 6px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  transition: box-shadow 0.2s, transform 0.2s;
  cursor: pointer;
}

.product-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
  transform: translateY(-2px);
}

.product-card img {
  width: 100%;
  height: 220px;
  object-fit: cover;
}

.product-card-content {
  padding: 1.25rem;
}

.product-card h3 {
  color: #1a2a3a;
}

.product-card .product-short-desc {
  color: #4a5568;
  font-size: 0.95rem;
}

.product-card .product-full-desc {
  display: none;
  color: #4a5568;
  font-size: 0.95rem;
}

/* Expanded state: show full, hide short */
.product-card.expanded .product-short-desc {
  display: none;
}

.product-card.expanded .product-full-desc {
  display: block;
}

/* ===========================
   Featured Products Section
   =========================== */
.featured-products {
  background-color: #f4f6f8;
}

.featured-products h2 {
  text-align: center;
  margin-bottom: 2rem;
}

/* ===========================
   Products Page
   =========================== */
.products-section h1 {
  text-align: center;
  margin-bottom: 2rem;
}

/* ===========================
   About Page
   =========================== */
.about-section {
  background-color: #ffffff;
}

.about-section h1 {
  text-align: center;
  margin-bottom: 2rem;
}

.about-section h2 {
  color: #1a2a3a;
  border-bottom: 2px solid #3498db;
  padding-bottom: 0.5rem;
  margin-bottom: 1rem;
}

.about-section p {
  color: #4a5568;
  max-width: 800px;
}

.about-block {
  margin-bottom: 2.5rem;
}

/* Team Cards */
.team-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 1.5rem;
}

.team-card {
  background-color: #f4f6f8;
  border-radius: 6px;
  padding: 1.5rem;
  text-align: center;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
}

.team-card img {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 1rem;
  border: 3px solid #3498db;
}

.team-card h3 {
  color: #1a2a3a;
  margin-bottom: 0.25rem;
}

.team-card p {
  color: #718096;
  font-style: italic;
  margin-bottom: 0;
}

/* Contact Info */
.contact-info p {
  margin-bottom: 0.5rem;
}

/* ===========================
   Footer
   =========================== */
footer {
  background-color: #1a2a3a;
  color: #cbd5e0;
  padding: 2.5rem 0 1.5rem;
  margin-top: auto;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-bottom: 1.5rem;
}

.footer-section h3 {
  color: #ffffff;
  margin-bottom: 0.75rem;
  font-size: 1.1rem;
}

.footer-section p {
  margin-bottom: 0.35rem;
  font-size: 0.9rem;
  color: #a0aec0;
}

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

.footer-links li {
  margin-bottom: 0.35rem;
}

.footer-links a {
  color: #a0aec0;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: #ffffff;
  text-decoration: none;
}

.footer-bottom {
  text-align: center;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
  color: #718096;
}

/* ===========================
   404 Page
   =========================== */
.not-found {
  text-align: center;
  padding: 5rem 1.5rem;
}

.not-found h1 {
  font-size: 5rem;
  color: #3498db;
  margin-bottom: 0.5rem;
}

.not-found h2 {
  margin-bottom: 1rem;
  color: #1a2a3a;
}

.not-found p {
  color: #4a5568;
  margin-bottom: 2rem;
  font-size: 1.1rem;
}

/* ===========================
   Responsive Breakpoints
   =========================== */
@media (max-width: 768px) {
  /* Navigation: hamburger visible, links hidden */
  .hamburger {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: #1a2a3a;
    flex-direction: column;
    padding: 0.5rem 0;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  }

  .nav-links a {
    padding: 0.75rem 1.5rem;
  }

  .nav-links a.active {
    border-bottom: none;
    border-left: 3px solid #3498db;
  }

  /* nav-open class: show links */
  nav.nav-open .nav-links {
    display: flex;
  }

  /* Header needs relative positioning for dropdown */
  header .container {
    position: relative;
  }

  /* Hero adjustments */
  .hero h1 {
    font-size: 1.75rem;
  }

  .hero p {
    font-size: 1rem;
  }

  /* Product grid: single column */
  .product-grid {
    grid-template-columns: 1fr;
  }

  /* Team grid: single column */
  .team-grid {
    grid-template-columns: 1fr;
  }

  /* Footer: single column */
  .footer-content {
    grid-template-columns: 1fr;
  }

  /* Typography adjustments */
  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.4rem; }
}