:root {
  --primary-color: #2563eb;
  --secondary-color: #1e40af;
  --accent-color: #3b82f6;
  --background-color: #f8fafc;
  --surface-color: #ffffff;
  --text-color: #1e293b;
  --text-color-light: #f1f5f9;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --gradient-primary: linear-gradient(135deg, #2563eb, #3b82f6);
  --gradient-secondary: linear-gradient(135deg, #1e40af, #2563eb);

  --font-family-base: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
  --font-family-heading: 'Georgia', 'Times New Roman', 'Hiragino Mincho ProN', serif;

  --header-height: 70px;
  --transition-speed: 0.3s;
}

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

body {
  font-family: var(--font-family-base);
  line-height: 1.7;
  color: var(--text-color);
  background-color: var(--background-color);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  color: var(--secondary-color);
  line-height: 1.3;
  margin-bottom: 1rem;
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
}

h2 {
  font-size: 2rem;
  font-weight: 600;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

p {
  margin-bottom: 1rem;
}

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

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Buttons */
.btn-primary {
  background: var(--gradient-primary);
  color: var(--text-color-light);
  padding: 1rem 2rem;
  border-radius: 8px;
  font-weight: 600;
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
  display: inline-block;
  border: none;
  cursor: pointer;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px var(--shadow-color);
  color: var(--text-color-light);
}

.btn-secondary {
  background-color: transparent;
  color: var(--primary-color);
  padding: 1rem 2rem;
  border: 2px solid var(--primary-color);
  border-radius: 8px;
  font-weight: 600;
  transition: all var(--transition-speed);
  display: inline-block;
}

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

.btn-outline {
  background-color: transparent;
  color: var(--accent-color);
  padding: 0.75rem 1.5rem;
  border: 1px solid var(--accent-color);
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition-speed);
  display: inline-block;
}

.btn-outline:hover {
  background-color: var(--accent-color);
  color: var(--text-color-light);
}

/* Header */
.header {
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: box-shadow var(--transition-speed);
}

.header.scrolled {
  box-shadow: 0 2px 20px var(--shadow-color);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: var(--header-height);
}

.logo a {
  font-family: var(--font-family-heading);
  font-size: 1.5rem;
  font-weight: bold;
  background: var(--gradient-primary);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.5rem;
  align-items: center;
  flex-wrap: wrap;
  max-width: 900px;
  justify-content: center;
}

.nav-item a {
  font-weight: 500;
  color: var(--text-color);
  padding: 0.4rem 0.8rem;
  border-radius: 8px;
  transition: var(--transition-speed);
  font-size: 0.9rem;
  white-space: nowrap;
}

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

.hamburger {
  display: none;
  cursor: pointer;
  flex-direction: column;
  width: 24px;
  height: 18px;
}

.hamburger-inner,
.hamburger-inner::before,
.hamburger-inner::after {
  width: 24px;
  height: 2px;
  background-color: var(--text-color);
  transition: all var(--transition-speed);
  border-radius: 1px;
}

.hamburger-inner {
  position: relative;
}

.hamburger-inner::before,
.hamburger-inner::after {
  content: '';
  position: absolute;
  left: 0;
}

.hamburger-inner::before {
  top: -8px;
}

.hamburger-inner::after {
  bottom: -8px;
}

/* Hero Section */
.hero {
  position: relative;
  background: var(--gradient-primary);
  min-height: 70vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('images/hero-main.jpg') center/cover;
  opacity: 0.1;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  width: 100%;
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}

@media (min-width: 992px) {
  .hero .container {
    grid-template-columns: 1fr 1fr;
  }
}

.hero-text {
  color: var(--text-color-light);
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1rem;
  color: var(--text-color-light);
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  opacity: 0.9;
}

.hero-description {
  font-size: 1.1rem;
  margin-bottom: 2rem;
  opacity: 0.9;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-image img {
  border-radius: 16px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  max-width: 100%;
  height: auto;
}

/* Sections */
section {
  padding: 4rem 0;
}

.section-intro {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  text-align: center;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

/* Market Overview */
.market-overview {
  background-color: var(--surface-color);
}

.market-overview h2 {
  text-align: center;
  margin-bottom: 2rem;
}

.market-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.stat-card {
  background: var(--gradient-secondary);
  color: var(--text-color-light);
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.2);
}

.stat-card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  color: var(--text-color-light);
  opacity: 0.9;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
}

.stat-card p {
  font-size: 0.9rem;
  opacity: 0.8;
}

/* Latest News */
.latest-news {
  background-color: var(--background-color);
}

.latest-news h2 {
  text-align: center;
  margin-bottom: 3rem;
}

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

.news-item {
  background-color: var(--surface-color);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 15px var(--shadow-color);
  border-left: 4px solid var(--primary-color);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.news-item:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 25px var(--shadow-color);
}

.news-item h3 {
  font-size: 1.2rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.news-item p {
  color: var(--text-muted);
  margin-bottom: 0;
}

/* Key Companies */
.key-companies {
  background-color: var(--surface-color);
}

.key-companies h2 {
  text-align: center;
  margin-bottom: 2rem;
}

.companies-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 3rem;
  margin-top: 3rem;
}

.company-card {
  background-color: var(--surface-color);
  border-radius: 16px;
  box-shadow: 0 8px 30px var(--shadow-color);
  overflow: hidden;
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.company-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 16px 40px var(--shadow-color);
}

.company-header {
  background: var(--gradient-primary);
  color: var(--text-color-light);
  padding: 2rem;
  text-align: center;
}

.company-header h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
  color: var(--text-color-light);
}

.company-tag {
  background-color: rgba(255, 255, 255, 0.2);
  padding: 0.5rem 1rem;
  border-radius: 20px;
  font-size: 0.9rem;
  font-weight: 500;
}

.company-content {
  padding: 2rem;
}

.company-content ul {
  margin: 1rem 0 1.5rem 1.5rem;
}

.company-content li {
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.company-cta {
  margin-top: 1.5rem;
}

/* Investment Strategy */
.investment-strategy {
  background-color: var(--background-color);
}

.investment-strategy h2 {
  text-align: center;
  margin-bottom: 3rem;
}

.strategy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.strategy-item {
  background-color: var(--surface-color);
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
  box-shadow: 0 4px 15px var(--shadow-color);
  transition: transform var(--transition-speed);
}

.strategy-item:hover {
  transform: translateY(-4px);
}

.strategy-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.strategy-item h3 {
  margin-bottom: 1rem;
}

.strategy-link {
  color: var(--primary-color);
  font-weight: 600;
  display: inline-block;
  margin-top: 1rem;
}

.strategy-link:hover {
  color: var(--secondary-color);
}

/* CTA Section */
.cta-section {
  background: var(--gradient-primary);
  color: var(--text-color-light);
  text-align: center;
}

.cta-section h2 {
  color: var(--text-color-light);
  margin-bottom: 1rem;
}

.cta-section p {
  font-size: 1.1rem;
  margin-bottom: 2rem;
  opacity: 0.9;
}

.cta-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Footer */
.footer {
  background-color: var(--text-color);
  color: var(--text-color-light);
  padding: 3rem 0 1rem;
}

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

.footer-section h3 {
  color: var(--text-color-light);
  margin-bottom: 1rem;
}

.footer-section h4 {
  color: var(--text-color-light);
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

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

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

.footer-section ul li a {
  color: rgba(241, 245, 249, 0.8);
  transition: color var(--transition-speed);
}

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

.footer-bottom {
  border-top: 1px solid rgba(241, 245, 249, 0.2);
  padding-top: 2rem;
  text-align: center;
}

.footer-bottom p {
  color: rgba(241, 245, 249, 0.6);
  margin-bottom: 0;
}

/* Article Layout */
.page-wrapper {
  padding: 4rem 0;
}

.main-content {
  display: flex;
  flex-direction: column;
  gap: 3rem;
  align-items: start;
}

.article-content {
  order: 2;
  width: 100%;
  background-color: var(--surface-color);
  border-radius: 12px;
  box-shadow: 0 4px 20px var(--shadow-color);
  overflow: hidden;
}

.sidebar {
  order: 1;
  width: 100%;
}

@media (min-width: 992px) {
  .main-content {
    flex-direction: row;
  }

  .article-content {
    order: 1;
    flex: 3;
  }

  .sidebar {
    order: 2;
    flex: 1;
  }
}

.article-header {
  background: var(--gradient-primary);
  color: var(--text-color-light);
  padding: 3rem 2rem;
  text-align: center;
}

.article-header h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--text-color-light);
}

.article-subtitle {
  font-size: 1.2rem;
  margin-bottom: 1.5rem;
  opacity: 0.9;
}

.article-meta {
  display: flex;
  gap: 2rem;
  justify-content: center;
  font-size: 0.9rem;
  opacity: 0.8;
}

.article-image {
  width: 100%;
  height: 300px;
  overflow: hidden;
}

.article-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.article-body {
  padding: 3rem 2rem;
}

.article-body h2 {
  margin-top: 3rem;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--primary-color);
}

.article-body h3 {
  margin-top: 2rem;
  margin-bottom: 1rem;
  color: var(--accent-color);
}

.article-body section {
  margin-bottom: 3rem;
}

.article-body ul, .article-body ol {
  margin: 1rem 0 1.5rem 2rem;
}

.article-body li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

/* Key Metrics */
.key-metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.metric-card {
  background: var(--gradient-secondary);
  color: var(--text-color-light);
  padding: 1.5rem;
  border-radius: 8px;
  text-align: center;
}

.metric-card h3 {
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
  color: var(--text-color-light);
  opacity: 0.9;
}

.metric-number {
  font-size: 2rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
}

.metric-card p {
  font-size: 0.8rem;
  opacity: 0.8;
  margin-bottom: 0;
}

/* Sidebar */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.sidebar > div {
  background-color: var(--surface-color);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 15px var(--shadow-color);
}

.sidebar h3 {
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.toc ul {
  list-style: none;
  padding: 0;
}

.toc li {
  margin-bottom: 0.5rem;
}

.toc a {
  color: var(--text-muted);
  transition: color var(--transition-speed);
  display: block;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-color);
}

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

.related-links ul, .ad-space ul {
  list-style: none;
  padding: 0;
}

.related-links li, .ad-space li {
  margin-bottom: 0.5rem;
}

.related-links a {
  color: var(--text-muted);
  transition: color var(--transition-speed);
}

.related-links a:hover {
  color: var(--primary-color);
}

.ad-space {
  background: var(--gradient-primary);
  color: var(--text-color-light);
}

.ad-space h3 {
  color: var(--text-color-light);
}

.ad-space p {
  color: var(--text-color-light);
  opacity: 0.9;
  margin-bottom: 1.5rem;
}

/* Responsive Design */
@media (max-width: 991px) {
  .nav-menu {
    position: fixed;
    top: var(--header-height);
    left: -100%;
    width: 100%;
    height: calc(100vh - var(--header-height));
    background-color: var(--surface-color);
    flex-direction: column;
    justify-content: flex-start;
    padding-top: 2rem;
    transition: left var(--transition-speed);
    box-shadow: 2px 0 10px var(--shadow-color);
  }

  .nav-menu.active {
    left: 0;
  }

  .hamburger {
    display: flex;
  }

  .hero h1 {
    font-size: 2.5rem;
  }

  .companies-grid {
    grid-template-columns: 1fr;
  }

  .cta-buttons {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 767px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero-cta {
    flex-direction: column;
  }

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

  .strategy-grid {
    grid-template-columns: 1fr;
  }

  .market-stats {
    grid-template-columns: 1fr;
  }
}