:root {
  color-scheme: light;
  --paper: #faf6ef;
  --paper-2: #fffdfa;
  --ink: #18212f;
  --muted: #627186;
  --line: rgba(24, 33, 47, 0.12);
  --accent: #9a674d;
  --teal: #2e6a64;
  --gold: #d8b16a;
  --shadow: 0 24px 60px rgba(60, 42, 26, 0.12);
  --serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Georgia, serif;
  --sans: "Avenir Next", "Trebuchet MS", "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
}

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

.topbar {
  width: min(1180px, calc(100vw - 24px));
  margin: 0 auto;
  padding: 18px 0 0;
}

.topbar-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.nav-link,
.lang-link {
  display: inline-flex;
  align-items: center;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid rgba(27, 36, 50, 0.12);
  background: rgba(255, 252, 246, 0.74);
  box-shadow: 0 10px 24px rgba(48, 35, 23, 0.08);
  color: var(--muted);
  font-size: 0.9rem;
  transition:
    transform 180ms ease,
    border-color 180ms ease,
    background 180ms ease;
}

.nav-link:hover,
.nav-link:focus-visible,
.lang-link:hover,
.lang-link:focus-visible,
.nav-link.active,
.lang-link.active {
  transform: translateY(-1px);
  border-color: rgba(154, 103, 77, 0.3);
  background: rgba(255, 255, 255, 0.92);
  color: var(--ink);
}

.language-switcher {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.page-shell {
  width: min(1180px, calc(100vw - 24px));
  margin: 0 auto;
  padding-bottom: 72px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  padding: 12px 16px;
  width: fit-content;
  border-radius: 999px;
  border: 1px solid rgba(27, 36, 50, 0.12);
  background: rgba(255, 252, 246, 0.78);
  color: var(--muted);
  font-size: 0.92rem;
  box-shadow: 0 10px 24px rgba(48, 35, 23, 0.08);
}

.lang-vi .nav-link,
.lang-vi .lang-link,
.lang-vi .back-link {
  font-size: 0.88rem;
}

@media (max-width: 760px) {
  .topbar {
    width: min(1180px, calc(100vw - 20px));
  }

  .page-shell {
    width: min(1180px, calc(100vw - 20px));
  }
}