/* Token ripresi da docs/UI.md; tipografia di sistema, nessuna risorsa esterna. */
:root {
  --bg: #F4F6F9;
  --surface: #FFFFFF;
  --border: #E3E7ED;
  --text: #16191F;
  --text-muted: #596170;
  --primary: #1F5FD1;
  --on-primary: #FFFFFF;
  --primary-soft: #E7EEFB;
  --ai: #5B35C4;
  --ai-soft: #EFEAFC;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-6: 24px;
  --space-8: 32px;
  --space-12: 48px;
  --radius: 12px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0F1217;
    --surface: #181C23;
    --border: #2A303A;
    --text: #E8EBF0;
    --text-muted: #A3ABB9;
    --primary: #7AA7F5;
    --on-primary: #0B1020;
    --primary-soft: #1D2A44;
    --ai: #B9A2F5;
    --ai-soft: #251F3D;
  }
}

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

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 88px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  overflow-wrap: break-word;
}

h1, h2, h3 { line-height: 1.2; margin: 0 0 var(--space-3); font-weight: 600; }
h1 { font-size: clamp(1.75rem, 6vw, 2.75rem); }
h2 { font-size: clamp(1.4rem, 4vw, 1.875rem); }
h3 { font-size: 1.0625rem; }
p { margin: 0 0 var(--space-4); }
ul { margin: 0; padding: 0; list-style: none; }
a { color: var(--primary); }
.muted { color: var(--text-muted); }

a:focus-visible, main:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
  border-radius: 4px;
}
main:focus { outline: none; }

.skip {
  position: absolute;
  left: var(--space-2);
  top: -100px;
  background: var(--surface);
  color: var(--text);
  padding: var(--space-3) var(--space-4);
  border: 2px solid var(--primary);
  border-radius: 8px;
  z-index: 10;
}
.skip:focus { top: var(--space-2); }

.wrap { width: 100%; max-width: 1100px; margin: 0 auto; padding: 0 var(--space-4); }
.narrow { max-width: 760px; }

.site-header { background: var(--surface); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 5; }
.bar { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2) var(--space-4); padding-top: var(--space-2); padding-bottom: var(--space-2); }
.brand { display: inline-flex; align-items: center; gap: var(--space-2); min-height: 44px; font-weight: 700; font-size: 1.125rem; color: var(--text); text-decoration: none; }
.brand-ico { color: var(--primary); }
.bar nav { order: 3; width: 100%; }
.nav { display: flex; flex-wrap: wrap; gap: 0 var(--space-2); }
.nav a, .langs a, .flinks a {
  display: inline-flex; align-items: center; min-height: 44px; min-width: 44px;
  padding: 0 var(--space-3); color: var(--text); text-decoration: none; border-radius: 8px;
}
.nav a:hover, .langs a:hover, .flinks a:hover { background: var(--primary-soft); }
.langs a[aria-current], .flinks a[aria-current] { background: var(--primary-soft); font-weight: 600; justify-content: center; }
.tools { margin-left: auto; display: flex; align-items: center; gap: var(--space-2); }
.langs { display: flex; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 44px; padding: 0 var(--space-6);
  border-radius: 10px; font-weight: 600; text-decoration: none;
  border: 2px solid var(--primary);
}
.btn-primary { background: var(--primary); color: var(--on-primary); }
.btn-secondary { background: transparent; color: var(--primary); }
.btn:hover { filter: brightness(1.08); }
.actions { display: flex; flex-wrap: wrap; gap: var(--space-3); }

.hero { padding: var(--space-12) 0; background: var(--primary-soft); }
.hero h1 { max-width: 20ch; }
.lead { font-size: 1.125rem; max-width: 60ch; color: var(--text); }

.sec { padding: var(--space-12) 0; }
.sec.alt { background: var(--surface); border-block: 1px solid var(--border); }

.grid { display: grid; grid-template-columns: 1fr; gap: var(--space-4); margin-top: var(--space-6); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: var(--space-6); }
.card p { margin: 0; color: var(--text-muted); }
.card .ico { color: var(--primary); margin-bottom: var(--space-3); width: 28px; height: 28px; }
.card.ai { background: var(--ai-soft); border-color: var(--ai); }
.card.ai .ico { color: var(--ai); }
.card.ai p { color: var(--text); }

.checks { display: grid; gap: var(--space-3); margin-top: var(--space-4); }
.checks li { display: flex; gap: var(--space-3); align-items: flex-start; }
.checks .ico { flex: none; color: var(--primary); margin-top: 2px; }

.site-footer { border-top: 1px solid var(--border); padding: var(--space-6) 0; color: var(--text-muted); }
.foot { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: var(--space-3); }
.foot p { margin: 0; }
.flinks { display: flex; flex-wrap: wrap; align-items: center; }
.flinks a { color: var(--primary); }

@media (min-width: 640px) {
  .grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .bar nav { order: 0; width: auto; flex: 1; }
  .tools { margin-left: 0; }
  .grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 420px) {
  .actions .btn { width: 100%; }
  .btn { padding: 0 var(--space-4); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}