/* === Custom Properties === */
:root {
  --color-primary: #1a2b4a;
  --color-secondary: #2c5282;
  --color-accent: #e2a03f;
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-text: #1a202c;
  --color-text-muted: #4a5568;
  --color-border: #e2e8f0;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --max-width: 1120px;
  --radius: 12px;
  --radius-sm: 8px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: clamp(1rem, 2.5vw, 1.125rem);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

a {
  color: var(--color-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

/* === Layout === */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

section {
  padding: clamp(3rem, 8vw, 6rem) 0;
}

/* === Header === */
.header {
  position: sticky;
  top: 0;
  background: var(--color-primary);
  z-index: 100;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0.05em;
}

.logo span {
  color: var(--color-accent);
}

/* === Language Toggle === */
.lang-toggle {
  display: flex;
  gap: 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.lang-toggle button {
  background: transparent;
  color: rgba(255, 255, 255, 0.7);
  border: none;
  padding: 0.4rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 600;
  font-family: var(--font-family);
  cursor: pointer;
  transition: all 0.2s ease;
  letter-spacing: 0.03em;
}

.lang-toggle button:not(:last-child) {
  border-right: 1px solid rgba(255, 255, 255, 0.15);
}

.lang-toggle button:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.1);
}

.lang-toggle button.active {
  background: var(--color-accent);
  color: var(--color-primary);
}

/* === Hero === */
.hero {
  text-align: center;
  padding: clamp(4rem, 10vw, 8rem) 0;
  background: linear-gradient(180deg, var(--color-primary) 0%, #243b5e 100%);
  color: #ffffff;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 700;
  margin-bottom: 1rem;
  line-height: 1.2;
}

.hero p {
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  color: rgba(255, 255, 255, 0.8);
  max-width: 600px;
  margin: 0 auto;
}

/* === About === */
.about {
  text-align: center;
}

.about h2 {
  font-size: clamp(1.5rem, 3.5vw, 2rem);
  color: var(--color-primary);
  margin-bottom: 1.5rem;
}

.about p {
  max-width: 680px;
  margin: 0 auto;
  color: var(--color-text-muted);
  line-height: 1.8;
}

/* === Subsidiaries === */
.subsidiaries {
  background: var(--color-surface);
}

.subsidiaries h2 {
  text-align: center;
  font-size: clamp(1.5rem, 3.5vw, 2rem);
  color: var(--color-primary);
  margin-bottom: 2.5rem;
}

.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  max-width: 800px;
  margin: 0 auto;
}

@media (min-width: 640px) {
  .cards {
    grid-template-columns: 1fr 1fr;
  }
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.card h3 {
  font-size: 1.25rem;
  color: var(--color-primary);
  margin-bottom: 0.75rem;
}

.card p {
  color: var(--color-text-muted);
  margin-bottom: 1.25rem;
  font-size: 0.95rem;
}

.card-link {
  display: inline-block;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--color-secondary);
  padding: 0.5rem 1.25rem;
  border: 2px solid var(--color-secondary);
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.card-link:hover {
  background: var(--color-secondary);
  color: #ffffff;
}

/* === Footer === */
.footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.6);
  padding: 2rem 0;
  text-align: center;
  font-size: 0.875rem;
}

.footer p + p {
  margin-top: 0.5rem;
}