:root {
  --color-bg-light: #f5f7fb;
  --color-bg-dark: #0f172a;
  --color-surface-light: #ffffff;
  --color-surface-dark: #111827;
  --color-primary: #2563eb;
  --color-primary-soft: #dbeafe;
  --color-text-main-light: #0f172a;
  --color-text-main-dark: #e5e7eb;
  --color-text-muted-light: #6b7280;
  --color-text-muted-dark: #9ca3af;
  --color-border-light: #e5e7eb;
  --color-border-dark: #1f2937;
  --radius-md: 8px;
  --radius-lg: 16px;
  --shadow-soft: 0 10px 30px rgba(15, 23, 42, 0.12);
  --transition-fast: 0.2s ease-in-out;
  --container-width: 1120px;
  --header-height: 72px;
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-main);
  line-height: 1.6;
  background-color: var(--color-bg-light);
  color: var(--color-text-main-light);
}

body.theme-dark {
  background-color: var(--color-bg-dark);
  color: var(--color-text-main-dark);
}

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

a {
  color: inherit;
  text-decoration: none;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4rem 0;
}

.section-alt {
  background-color: var(--color-surface-light);
}

body.theme-dark .section-alt {
  background-color: var(--color-surface-dark);
}

.section-header {
  text-align: center;
  margin-bottom: 2.5rem;
}

.section-header h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.section-header p {
  margin: 0;
  color: var(--color-text-muted-light);
}

body.theme-dark .section-header p {
  color: var(--color-text-muted-dark);
}

.two-columns {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: 2rem;
}

@media (max-width: 768px) {
  .two-columns {
    grid-template-columns: 1fr;
  }
}