:root {
  color-scheme: light dark;
  --page-bg: #f8f9fc;
  --surface: #ffffff;
  --text: #353942;
  --muted: #667085;
  --border: rgba(55, 65, 81, 0.12);
  --accent: #597ff0;
  --accent-soft: #edf2ff;
  --warning-bg: #fff4ec;
  --warning-border: #e48a50;
  --shadow: 0 18px 55px rgba(50, 62, 90, 0.09);
}

@media (prefers-color-scheme: dark) {
  :root {
    --page-bg: #10141d;
    --surface: #181f2c;
    --text: #e7ebf4;
    --muted: #b9c2d5;
    --border: rgba(255, 255, 255, 0.11);
    --accent: #8ca9ff;
    --accent-soft: #202c48;
    --warning-bg: #30231f;
    --warning-border: #e39a6b;
    --shadow: 0 18px 55px rgba(0, 0, 0, 0.24);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--page-bg);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.68;
}

a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 2;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--page-bg) 90%, transparent);
  backdrop-filter: blur(14px);
}

.site-header-inner,
.article-shell,
.site-footer {
  width: min(820px, calc(100% - 32px));
  margin-inline: auto;
}

.site-header-inner {
  min-height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand,
.language-links,
.article-nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px 16px;
}

.brand { color: var(--text); font-weight: 700; text-decoration: none; }
.brand-mark { width: 24px; height: 24px; display: block; border-radius: 50%; }
.language-links { justify-content: flex-end; font-size: 13px; }
.language-links a[aria-current="page"] { color: var(--text); font-weight: 700; text-decoration: none; }

.article-shell {
  margin-block: 34px 48px;
  padding: clamp(24px, 5vw, 56px);
  border: 1px solid var(--border);
  border-radius: 28px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.eyebrow { margin: 0 0 8px; color: var(--accent); font-size: 13px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; }
h1 { margin: 0 0 24px; font-size: clamp(32px, 6vw, 52px); line-height: 1.08; letter-spacing: -.035em; }
h2 { margin: 48px 0 16px; font-size: clamp(24px, 4vw, 32px); line-height: 1.22; letter-spacing: -.02em; }
h3 { margin: 34px 0 12px; font-size: 21px; line-height: 1.3; }
p { margin: 0 0 16px; }
ul { margin: 12px 0 22px; padding-left: 24px; }
li { margin: 8px 0; }
strong { color: var(--text); }

.lead { color: var(--muted); font-size: 19px; line-height: 1.6; }
.cycle-note { padding: 16px 18px; border-left: 4px solid var(--accent); border-radius: 0 12px 12px 0; background: var(--accent-soft); font-weight: 650; }
.safety-note { margin-block: 34px; padding: 20px; border: 1px solid var(--warning-border); border-left-width: 5px; border-radius: 16px; background: var(--warning-bg); }
.safety-note h2, .safety-note h3 { margin-top: 0; }
.faq-item { padding-block: 4px 18px; border-bottom: 1px solid var(--border); }
.faq-item:last-child { border-bottom: 0; }
.article-nav { margin-top: 42px; padding-top: 24px; border-top: 1px solid var(--border); }
.article-nav a { font-weight: 600; }
.site-footer { padding-bottom: 36px; color: var(--muted); font-size: 13px; text-align: center; }

@media (max-width: 560px) {
  .site-header-inner { align-items: flex-start; flex-direction: column; padding-block: 12px; }
  .language-links { justify-content: flex-start; }
  .article-shell { width: 100%; margin-top: 0; border-inline: 0; border-radius: 0; box-shadow: none; }
  .lead { font-size: 17px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}