:root {
  color-scheme: light dark;
  --bg: #f8fafc;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: #cbd5e1;
  --link: #0f766e;
  --link-hover: #115e59;
  --focus: #1d4ed8;
  --teal: #0f766e;
  --teal-hover: #115e59;
  --teal-accent: #0d9488;
  --indigo: #4f46e5;
  --indigo-hover: #4338ca;
  --indigo-accent: #4f46e5;
  --code-bg: #e2e8f0;
  --error: #b91c1c;
  --warn: #92400e;
  --radius: 0.75rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --surface: #111827;
    --text: #e5e7eb;
    --muted: #a3adbd;
    --border: #334155;
    --link: #5eead4;
    --link-hover: #99f6e4;
    --focus: #93c5fd;
    --teal-accent: #2dd4bf;
    --indigo-accent: #818cf8;
    --code-bg: #1f2937;
    --error: #fca5a5;
    --warn: #fcd34d;
  }
}

@media (prefers-contrast: more) {
  :root {
    --muted: var(--text);
    --border: currentColor;
  }
}

*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main { flex: 1 0 auto; min-width: 0; padding-block: 2rem 3rem; }
body, .wrap, .prose { overflow-wrap: break-word; }
main:focus { outline: none; }

.wrap { width: min(100% - 2rem, 64rem); margin-inline: auto; }
.prose { width: min(100% - 2rem, 46rem); margin-inline: auto; }

h1, h2, h3 { line-height: 1.25; margin: 2rem 0 0.75rem; }
h1 { font-size: clamp(1.9rem, 1.2rem + 3vw, 2.75rem); margin-top: 0; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.2rem; }
p, ul, ol { margin: 0 0 1rem; }
ul, ol { padding-inline-start: 1.5rem; }
li { margin-bottom: 0.35rem; }
hr { border: 0; border-top: 1px solid var(--border); margin: 2rem 0; }
strong { font-weight: 650; }

code {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: 0.92em;
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 0.25rem;
  direction: ltr;
  unicode-bidi: isolate;
  overflow-wrap: anywhere;
}

a { color: var(--link); }
a:hover { color: var(--link-hover); }
main a:not(.btn) { text-decoration: underline; text-underline-offset: 0.2em; }

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
  border-radius: 0.25rem;
}

.skip-link {
  position: absolute;
  inset-inline-start: 0.5rem;
  top: -4rem;
  z-index: 10;
  background: var(--surface);
  color: var(--text);
  padding: 0.75rem 1rem;
  border: 2px solid var(--text);
  border-radius: 0.5rem;
}
.skip-link:focus { top: 0.5rem; }

.site-header { border-bottom: 1px solid var(--border); background: var(--surface); }
.header-inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.25rem 1.5rem; }
.brand {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text);
  text-decoration: none;
}
.brand:hover { color: var(--text); }
.nav-list, .footer-list { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 0 1.25rem; }
.nav-list li, .footer-list li { margin: 0; }
.nav-list a, .footer-list a {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  color: var(--text);
  text-decoration: none;
}
.nav-list a:hover, .footer-list a:hover { text-decoration: underline; color: var(--text); }
.nav-list a[aria-current="page"] { font-weight: 700; text-decoration: underline; text-underline-offset: 0.3em; }

.site-footer { border-top: 1px solid var(--border); background: var(--surface); padding-block: 1.25rem; }
.footer-note { margin: 0.5rem 0 0; color: var(--muted); font-size: 0.95rem; }

.lead { font-size: 1.25rem; color: var(--muted); max-width: 40rem; }
.hero { padding-block: 1.5rem 1rem; }

.cards { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(min(100%, 18rem), 1fr)); }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.25rem 0.5rem;
}
.card h3 { margin-top: 0; }
.card--linkshield { border-top: 0.375rem solid var(--teal-accent); }
.card--safescan { border-top: 0.375rem solid var(--indigo-accent); }
.status { color: var(--muted); font-size: 0.95rem; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3rem;
  max-width: 100%;
  padding: 0.5rem 1rem;
  overflow-wrap: anywhere;
  border: 2px solid transparent;
  border-radius: 0.5rem;
  font-weight: 650;
  text-decoration: none;
  color: #ffffff;
  text-align: center;
}
.btn:hover { color: #ffffff; }
.btn--teal { background: var(--teal); }
.btn--teal:hover { background: var(--teal-hover); }
.btn--indigo { background: var(--indigo); }
.btn--indigo:hover { background: var(--indigo-hover); }
.btn--outline { background: transparent; color: var(--text); border-color: var(--text); }
.btn--outline:hover { background: var(--code-bg); color: var(--text); }
.btn-row { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-bottom: 1rem; }

.principles { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); }
.principle { border-inline-start: 0.25rem solid var(--border); padding-inline-start: 1rem; }
.principle h3 { margin-top: 0; }

.callout {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin-bottom: 1.25rem;
}
.callout > :last-child { margin-bottom: 0; }

.meta { color: var(--muted); }
.crumbs ol { display: flex; flex-wrap: wrap; align-items: center; gap: 0 0.5rem; margin: 0; padding: 0; list-style: none; font-size: 0.95rem; color: var(--muted); }
.crumbs li { display: flex; align-items: center; gap: 0.6rem; }
/* A drawn chevron, not a character, so it points to the next level in both directions without bidi mirroring. */
.crumbs li + li::before { content: ""; width: 0.4em; height: 0.4em; border: solid currentColor; border-width: 0 1.5px 1.5px 0; transform: rotate(-45deg); }
[dir="rtl"] .crumbs li + li::before { transform: rotate(135deg); }
.crumbs a { display: inline-flex; align-items: center; min-height: 2.75rem; color: inherit; }
.policy h2 { font-size: 1.3rem; }

/* QR code generator */
.qr { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.5rem 2.5rem; margin-block: 1.5rem; }
@media (min-width: 52rem) {
  .qr { grid-template-columns: minmax(0, 1fr) minmax(0, 22rem); grid-template-rows: auto 1fr; align-items: start; }
  .qr-output { grid-column: 2; grid-row: 1 / span 2; position: sticky; top: 1rem; }
  .qr-inputs, .qr-look { grid-column: 1; }
}
.qr fieldset { border: 1px solid var(--border); border-radius: var(--radius); margin: 0 0 1.25rem; padding: 0.75rem 1.25rem 1rem; min-width: 0; }
.qr legend { font-weight: 650; padding-inline: 0.25rem; }
.qr label { display: block; font-weight: 600; margin-top: 0.75rem; }
.qr-types { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 11rem), 1fr)); gap: 0 1rem; }
.qr-types label, .qr label.check { display: flex; align-items: center; gap: 0.6rem; min-height: 2.75rem; margin: 0; font-weight: 400; }
.qr input[type="radio"], .qr input[type="checkbox"] { width: 1.25rem; height: 1.25rem; margin: 0; flex: none; accent-color: var(--indigo-accent); }
.qr input[type="text"], .qr input[type="url"], .qr input[type="email"], .qr input[type="tel"], .qr input[type="password"], .qr textarea, .qr select {
  display: block;
  width: 100%;
  min-height: 2.75rem;
  margin-top: 0.25rem;
  padding: 0.5rem 0.75rem;
  font: inherit;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--muted);
  border-radius: 0.5rem;
}
.qr [aria-invalid="true"] { border: 2px solid var(--error); }
.qr input[type="color"] { display: block; width: 6rem; height: 2.75rem; margin-top: 0.25rem; padding: 0.15rem; background: var(--surface); border: 1px solid var(--muted); border-radius: 0.5rem; }
.qr-panel { margin-bottom: 1.25rem; }
.qr-colors { display: flex; flex-wrap: wrap; gap: 0 2rem; }
.qr-colors > div { max-width: 100%; }
.qr-color-row { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem; }
.qr .qr-color-row input[type="text"] { width: 7.5rem; max-width: 100%; font-family: ui-monospace, "Cascadia Mono", Consolas, monospace; }
.qr-presets-label { font-weight: 600; margin: 0.25rem 0 0.4rem; }
.qr-presets { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 0.5rem; }
.qr-preset { display: inline-flex; align-items: center; gap: 0.45rem; min-height: 2.75rem; padding: 0.4rem 0.8rem; font: inherit; color: var(--text); background: var(--surface); border: 1px solid var(--muted); border-radius: 999px; cursor: pointer; }
.qr-preset:hover { border-color: var(--text); }
.qr-dot { width: 1.1rem; height: 1.1rem; flex: none; border-radius: 50%; border: 1px solid var(--border); }
.qr-dot--black { background: #000000; }
.qr-dot--blue { background: #1e3a8a; }
.qr-dot--green { background: #14532d; }
.qr-dot--red { background: #7f1d1d; }
.qr-dot--purple { background: #4c1d95; }
.hint { color: var(--muted); font-size: 0.95rem; margin: 0.25rem 0 0; }
.qr-output h2 { margin-top: 0; }
.qr-msg { display: flex; gap: 0.6rem; align-items: flex-start; margin: 0 0 0.75rem; padding: 0.6rem 0.75rem; border: 1px solid currentColor; border-inline-start-width: 0.35rem; border-radius: 0.5rem; background: var(--surface); }
.qr-msg span { color: var(--text); }
.qr-msg--error { color: var(--error); }
.qr-msg--warn { color: var(--warn); }
.qr-icon { width: 1.4rem; height: 1.4rem; flex: none; margin-top: 0.1rem; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.qr-empty { color: var(--muted); border: 1px dashed var(--border); border-radius: var(--radius); padding: 2rem 1rem; text-align: center; }
.qr-preview { display: block; width: 100%; max-width: 20rem; height: auto; aspect-ratio: 1; border: 1px solid var(--border); border-radius: 0.5rem; }
.qr-safety { margin-top: 1rem; }
.qr-guide { max-width: 46rem; margin-top: 2.5rem; border-top: 1px solid var(--border); }
.qr-guide h3 { font-size: 1.1rem; margin-top: 1.5rem; }

/* Guides */
.card h2 { margin-top: 0; font-size: 1.3rem; }
.guide-table { width: 100%; border-collapse: collapse; margin: 0 0 1.5rem; font-size: 0.95rem; line-height: 1.5; }
.guide-table caption { text-align: start; font-weight: 650; margin-bottom: 0.5rem; }
.guide-table th, .guide-table td { text-align: start; vertical-align: top; padding: 0.6rem 0.75rem; border: 1px solid var(--border); }
.guide-table thead th { background: var(--code-bg); }
.guide-table tbody th { font-weight: 650; }
/* Narrow screens: each row becomes a block, with the column name before each cell. */
@media (max-width: 40rem) {
  .guide-table thead { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
  .guide-table tr { display: block; border: 1px solid var(--border); border-radius: 0.5rem; margin-bottom: 0.75rem; padding: 0.5rem 0.75rem; }
  .guide-table tbody th, .guide-table td { display: block; border: 0; padding: 0.25rem 0; }
  .guide-table td::before { content: attr(data-label) ": "; font-weight: 650; }
}

@media (forced-colors: active) {
  .btn { border-color: ButtonText; }
  .card, .callout, .site-header, .site-footer { border-color: CanvasText; }
  .qr-msg { border-color: CanvasText; }
  .qr-icon { stroke: CanvasText; }
}

@media print {
  .site-header, .site-footer, .skip-link { display: none; }
  body { background: #fff; color: #000; }
}