/* ============================================
   Tokyo Detached Housing Market - Styles
   ============================================ */

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

/* Color Scheme */
:root {
  --primary-color: #1a3a52;
  --secondary-color: #2d5a7a;
  --accent-color: #e67e22;
  --text-dark: #333;
  --text-light: #666;
  --bg-light: #f9f9f9;
  --border-color: #ddd;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: #fff;
}

/* ============================================
   Header & Navigation
   ============================================ */

header {
  background-color: var(--primary-color);
  color: white;
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 2rem;
}

.logo {
  font-size: 1.3rem;
  font-weight: bold;
  letter-spacing: 0.5px;
}

.logo-text {
  color: white;
}

header nav ul {
  display: flex;
  list-style: none;
  gap: 0;
}

header nav ul li a {
  display: block;
  color: white;
  text-decoration: none;
  padding: 0.8rem 1.2rem;
  transition: all 0.3s ease;
  font-size: 0.95rem;
  border-bottom: 3px solid transparent;
}

header nav ul li a:hover,
header nav ul li a.active {
  background-color: var(--secondary-color);
  border-bottom-color: var(--accent-color);
}

/* Mobile Menu Button */
.mobile-menu-btn {
  display: none;
  flex-direction: column;
  background: none;
  border: none;
  cursor: pointer;
}

.hamburger-line {
  width: 25px;
  height: 3px;
  background-color: white;
  margin: 4px 0;
  transition: 0.3s;
}

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

.hero {
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  min-height: 400px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  color: white;
  text-align: center;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(26, 58, 82, 0.5);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 600px;
  padding: 2rem;
}

.hero-content h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  font-weight: bold;
  letter-spacing: 1px;
}

.hero-subtitle {
  font-size: 1.3rem;
  margin-bottom: 1.5rem;
  font-weight: 300;
  line-height: 1.5;
}

/* ============================================
   Main Content
   ============================================ */

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

article {
  line-height: 1.8;
}

/* Content Sections */
.content-section {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
}

.content-section:last-child {
  border-bottom: none;
}

.content-section h2 {
  font-size: 1.8rem;
  color: var(--primary-color);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--accent-color);
  display: inline-block;
}

.content-section h3 {
  font-size: 1.3rem;
  color: var(--secondary-color);
  margin-top: 1.5rem;
  margin-bottom: 0.8rem;
}

.content-section p {
  color: var(--text-light);
  margin-bottom: 1rem;
  text-align: justify;
}

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

/* ============================================
   Lists
   ============================================ */

.feature-list,
.keyword-list {
  list-style: none;
  margin: 1.5rem 0;
  padding-left: 0;
}

.feature-list li,
.keyword-list li {
  padding: 0.7rem 0 0.7rem 2rem;
  position: relative;
  color: var(--text-light);
}

.feature-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--accent-color);
  font-weight: bold;
  font-size: 1.2rem;
}

.keyword-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0.5rem;
}

.keyword-list li {
  background-color: var(--bg-light);
  padding: 0.7rem 1rem;
  border-radius: 4px;
  border-left: 4px solid var(--accent-color);
  padding-left: 1rem;
}

.keyword-list li::before {
  content: none;
}

/* ============================================
   Overview Section (Index)
   ============================================ */

.overview {
  background-color: var(--bg-light);
  padding: 3rem 2rem;
  margin: 3rem 0;
  border-radius: 8px;
}

.overview h2 {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 2rem;
  text-align: center;
}

.overview-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.overview-item {
  background-color: white;
  padding: 1.5rem;
  border-radius: 8px;
  border-left: 4px solid var(--accent-color);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.overview-item h3 {
  color: var(--secondary-color);
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.overview-item p {
  color: var(--text-light);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ============================================
   News Section
   ============================================ */

.news-section {
  background-color: white;
  padding: 3rem 2rem;
  margin: 3rem 0;
}

.news-container {
  max-width: 1200px;
  margin: 0 auto;
}

.news-section h2 {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 2rem;
  text-align: center;
  border-bottom: 3px solid var(--accent-color);
  padding-bottom: 1rem;
  display: block;
}

.news-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
}

.news-item {
  background-color: var(--bg-light);
  padding: 1.5rem;
  border-radius: 8px;
  border-top: 4px solid var(--accent-color);
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.news-item:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
  transform: translateY(-2px);
}

.news-item h3 {
  color: var(--secondary-color);
  margin-bottom: 0.8rem;
  font-size: 1rem;
}

.news-item p {
  color: var(--text-light);
  font-size: 0.9rem;
  line-height: 1.6;
}

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

footer {
  background-color: var(--primary-color);
  color: white;
  padding: 3rem 2rem 1rem;
  margin-top: 3rem;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-section h3 {
  color: white;
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.footer-section p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-section ul {
  list-style: none;
}

.footer-section ul li {
  margin-bottom: 0.5rem;
}

.footer-section ul li a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.3s ease;
}

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

.footer-bottom {
  text-align: center;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.85rem;
}

/* ============================================
   Responsive Design
   ============================================ */

@media (max-width: 768px) {
  .header-content {
    padding: 0 1rem;
  }

  header nav ul {
    flex-direction: column;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background-color: var(--primary-color);
    gap: 0;
    display: none;
  }

  header nav ul.active {
    display: flex;
  }

  header nav ul li a {
    padding: 0.8rem 1rem;
    border-bottom: none;
    border-left: 4px solid transparent;
  }

  header nav ul li a:hover,
  header nav ul li a.active {
    background-color: var(--secondary-color);
    border-left-color: var(--accent-color);
    border-bottom-color: transparent;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .hero {
    min-height: 300px;
  }

  .hero-content h1 {
    font-size: 1.8rem;
  }

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

  main {
    padding: 2rem 1rem;
  }

  .content-section h2 {
    font-size: 1.5rem;
  }

  .content-section h3 {
    font-size: 1.1rem;
  }

  .news-list {
    grid-template-columns: 1fr;
  }

  .overview-content {
    grid-template-columns: 1fr;
  }

  .keyword-list {
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  }

  .footer-content {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .logo {
    font-size: 1rem;
  }

  .hero-content h1 {
    font-size: 1.5rem;
  }

  .hero-subtitle {
    font-size: 0.9rem;
  }

  main {
    padding: 1.5rem 1rem;
  }

  .content-section {
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
  }

  .content-section h2 {
    font-size: 1.3rem;
  }

  article {
    font-size: 0.9rem;
  }

  footer {
    padding: 2rem 1rem 1rem;
  }
}

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

.cta-button {
  display: inline-block;
  background-color: var(--accent-color);
  color: white;
  padding: 0.8rem 1.5rem;
  border-radius: 4px;
  text-decoration: none;
  transition: all 0.3s ease;
  font-weight: 600;
  margin-top: 1rem;
}

.cta-button:hover {
  background-color: #d66a1a;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(230, 126, 34, 0.3);
}