:root {
  color-scheme: light;
  --bg: #f3f5f8;
  --surface: #ffffff;
  --text: #152033;
  --muted: #5b6b82;
  --border: #e2e8f0;
  --accent: #2563eb;
  --accent-soft: #eff4ff;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top left, #dbeafe 0%, transparent 40%),
    linear-gradient(180deg, #eef2ff 0%, var(--bg) 40%);
  color: var(--text);
  line-height: 1.6;
}

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

.wrap {
  width: min(840px, calc(100% - 2rem));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(10px);
  background: rgb(255 255 255 / 86%);
  border-bottom: 1px solid var(--border);
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

.brand img {
  border-radius: 10px;
}

.brand-name {
  margin: 0;
  font-weight: 700;
  font-size: 1rem;
}

.brand-sub {
  margin: 0;
  color: var(--muted);
  font-size: 0.85rem;
}

.lang-switch {
  display: inline-flex;
  gap: 0.25rem;
  padding: 0.2rem;
  border-radius: 999px;
  background: var(--accent-soft);
}

.lang-btn {
  border: 0;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-weight: 700;
  font-size: 0.8rem;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  cursor: pointer;
}

.lang-btn.is-active {
  background: var(--accent);
  color: #fff;
}

main {
  padding: 1.5rem 0 3rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1.25rem;
  padding: 1.5rem 1.4rem 2rem;
  box-shadow: 0 10px 30px rgb(21 32 51 / 6%);
}

.meta {
  margin: 0 0 0.75rem;
  color: var(--muted);
  font-size: 0.9rem;
}

h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.6rem, 3vw, 2rem);
  line-height: 1.2;
}

.lead {
  margin: 0 0 1.5rem;
  color: var(--muted);
  font-size: 1.05rem;
}

section + section {
  margin-top: 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
}

h2 {
  margin: 0 0 0.65rem;
  font-size: 1.15rem;
}

h3 {
  margin: 1rem 0 0.4rem;
  font-size: 1rem;
}

p,
li {
  color: #243247;
}

ul {
  margin: 0.4rem 0 0;
  padding-left: 1.2rem;
}

li + li {
  margin-top: 0.4rem;
}

.site-footer {
  padding: 1rem 0 2rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer p {
  margin: 0;
  color: inherit;
}

@media (min-width: 720px) {
  .card {
    padding: 2rem 2.25rem 2.5rem;
  }
}