:root {
  --max-width: 1160px;
  --color-primary: #2452D9;
  --color-primary-dark: #1B3FAE;
  --color-accent: #0F9D64;
  --color-accent-dark: #0B7A4E;
  --color-text: #161B33;
  --color-text-muted: #565F7A;
  --color-bg: #ffffff;
  --color-bg-alt: #F5F7FB;
  --color-border: #E2E6F0;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 2px rgba(22, 27, 51, 0.06);
  --shadow-md: 0 8px 24px rgba(22, 27, 51, 0.08);
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: 'Inter', 'Segoe UI', system-ui, sans-serif;
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-text);
  margin: 0 0 0.6em;
}

h1 { font-size: clamp(1.9rem, 4vw, 2.6rem); font-weight: 700; letter-spacing: -0.01em; }
h2 { font-size: clamp(1.4rem, 3vw, 1.9rem); margin-top: 2.4em; }
h3 { font-size: 1.2rem; margin-top: 1.6em; }
p { margin: 0 0 1.1em; color: var(--color-text); }
ul, ol { margin: 0 0 1.1em; padding-left: 1.3em; }
li { margin-bottom: 0.4em; }
a { color: var(--color-primary); text-decoration: underline; text-decoration-color: rgba(36,82,217,0.35); text-underline-offset: 2px; }
a:hover { text-decoration-color: currentColor; }
img { max-width: 100%; display: block; }

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

.icon { flex-shrink: 0; }

/* Header */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
  position: sticky;
  top: 0;
  z-index: 40;
}
.site-header__inner { height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.site-logo__img { height: 40px; width: auto; display: block; }
.site-nav { display: none; gap: 1.6rem; align-items: center; }
.site-nav a { color: var(--color-text); text-decoration: none; font-weight: 500; font-size: 0.95rem; }
.site-nav a:hover, .site-nav a.active { color: var(--color-primary); }
.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.4rem;
  color: var(--color-text);
  cursor: pointer;
}

@media (min-width: 768px) {
  .site-nav { display: flex; }
  .nav-toggle { display: none; }
}

.site-nav.is-open {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: 68px;
  left: 0;
  right: 0;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 1.5rem 1.5rem;
  gap: 0.9rem;
  box-shadow: var(--shadow-md);
}

/* Footer */
.site-footer { background: var(--color-bg-alt); border-top: 1px solid var(--color-border); margin-top: 4rem; }
.site-footer__inner { padding: 3rem 1.5rem 2rem; display: grid; gap: 2rem; }
.site-footer__tagline { color: var(--color-text-muted); font-size: 0.9rem; max-width: 32ch; margin-top: 0.8rem; }
.site-footer__nav { display: flex; flex-wrap: wrap; gap: 1rem 1.5rem; }
.site-footer__nav a { color: var(--color-text); text-decoration: none; font-size: 0.9rem; }
.site-footer__nav a:hover { color: var(--color-primary); }
.site-footer__legal { border-top: 1px solid var(--color-border); padding-top: 1.5rem; font-size: 0.8rem; color: var(--color-text-muted); }
.site-footer__legal p { margin-bottom: 0.6em; }

@media (min-width: 900px) {
  .site-footer__inner { grid-template-columns: 1.4fr 1fr; }
  .site-footer__legal { grid-column: 1 / -1; }
}

main { display: block; }

.text-page { padding: 3rem 0 4rem; max-width: 760px; }
.text-page h1 { margin-bottom: 0.4em; }
.text-page .updated { color: var(--color-text-muted); font-size: 0.9rem; margin-bottom: 2rem; }