:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --text: #121826;
  --muted: #5b6577;
  --border: #e2e7f0;
  --accent: #2455e6;
  --accent-hover: #1b43c0;
  --accent-soft: #e9efff;
  --accent-text: #ffffff;
  --ok: #138a3d;
  --ok-soft: #e4f6ea;
  --warn: #a85a00;
  --error: #c62828;
  --shadow: 0 1px 2px rgba(18, 24, 38, 0.05), 0 8px 24px rgba(18, 24, 38, 0.06);
  --radius: 16px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1118;
    --card: #161b25;
    --text: #e9edf5;
    --muted: #97a1b3;
    --border: #262d3b;
    --accent: #6c93ff;
    --accent-hover: #8aa8ff;
    --accent-soft: #1d2740;
    --accent-text: #0a1020;
    --ok: #4cc26b;
    --ok-soft: #14291c;
    --warn: #f0a24a;
    --error: #ff6b6b;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.35);
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

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

/* Site header */
.site-header { background: var(--card); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 10; }
.site-header-in { max-width: 880px; margin: 0 auto; padding: 12px 20px; display: flex; align-items: center; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 750; font-size: 1.1rem; color: var(--text); text-decoration: none; letter-spacing: -0.01em; }
.brand:hover { color: var(--text); }
.logo { width: 30px; height: 30px; border-radius: 9px; background: var(--accent); color: var(--accent-text); display: grid; place-items: center; font-weight: 800; font-size: 1rem; }
.site-nav { margin-left: auto; display: flex; gap: 4px; flex-wrap: wrap; justify-content: flex-end; }
.site-nav a { color: var(--muted); text-decoration: none; font-size: 0.92rem; font-weight: 550; padding: 6px 10px; border-radius: 8px; }
.site-nav a:hover { background: var(--accent-soft); color: var(--accent); }
@media (max-width: 640px) { .site-nav { display: none; } }

main { max-width: 880px; margin: 0 auto; padding: 36px 20px 56px; }

/* Hero */
header { margin-bottom: 28px; }
h1 { font-size: clamp(1.9rem, 4.5vw, 2.7rem); line-height: 1.12; letter-spacing: -0.025em; margin: 0 0 14px; font-weight: 800; }
h2 { font-size: 1.2rem; letter-spacing: -0.01em; margin: 0 0 16px; }
h2:not(:first-child) { margin-top: 36px; }
.lead { color: var(--muted); font-size: 1.1rem; margin: 0 0 20px; max-width: 62ch; }
.lead:has(+ .usage:not([hidden])) { margin-bottom: 8px; }
.usage { color: var(--muted); font-size: 0.92rem; margin: 0 0 12px; }
.usage strong { color: var(--text); }

.badges { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 4px; padding: 0; }
.badges li { background: var(--ok-soft); color: var(--ok); font-size: 0.85rem; font-weight: 650; padding: 5px 12px; border-radius: 999px; }
.badges li::before { content: "✓ "; }

/* Cards */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
  margin-bottom: 24px;
}
@media (max-width: 520px) { .card { padding: 20px; } }

/* Upload */
.drop {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 40px 20px;
  border: 2px dashed var(--border);
  border-radius: 14px;
  background: var(--bg);
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.drop:hover, .drop.over { border-color: var(--accent); background: var(--accent-soft); }
.drop strong { color: var(--accent); font-size: 1.1rem; }

.hint { color: var(--muted); font-size: 0.9rem; }

.files { list-style: none; padding: 0; margin: 12px 0 0; }
.files li { padding: 4px 0; overflow-wrap: anywhere; }

.tips { color: var(--muted); font-size: 0.93rem; padding-left: 20px; margin: 18px 0 22px; }
.tips li { margin-bottom: 4px; }

/* Buttons */
button, .button {
  display: inline-block;
  font: inherit;
  font-weight: 650;
  padding: 11px 20px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.05s;
}
button:hover:not(:disabled), .button:hover { border-color: var(--accent); color: var(--accent); }
button:active:not(:disabled), .button:active { transform: translateY(1px); }
.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.primary:hover:not(:disabled), a.primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--accent-text); }
button:disabled { opacity: 0.45; cursor: not-allowed; }
button:focus-visible, .button:focus-visible, summary:focus-visible { outline: 3px solid var(--accent-soft); outline-offset: 2px; }
#convert { width: 100%; padding: 14px 20px; font-size: 1.05rem; }

.status { min-height: 1.5em; margin: 12px 0 0; }
.status.error { color: var(--error); }

/* Result */
.result { display: flex; gap: 28px; align-items: flex-start; flex-wrap: wrap; margin-bottom: 8px; }
.result img { width: 220px; height: auto; border: 1px solid var(--border); border-radius: 8px; background: #fff; box-shadow: var(--shadow); }
.buttons { display: flex; flex-wrap: wrap; gap: 8px; }
.checks { list-style: none; padding: 0; margin: 0 0 16px; }
.checks li { padding: 3px 0; }
.checks .ok::before { content: "✓ "; color: var(--ok); font-weight: 800; }
.checks .warn::before { content: "! "; color: var(--warn); font-weight: 800; }

/* Format picker */
.segmented { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 24px; }
.segmented label {
  padding: 10px 16px;
  cursor: pointer;
  border: 1px solid var(--border);
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.95rem;
  background: var(--card);
  transition: border-color 0.15s, background 0.15s;
}
.segmented label:hover { border-color: var(--accent); }
.segmented input { position: absolute; opacity: 0; }
.segmented label:has(input:checked) { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.segmented label:has(input:focus-visible) { outline: 3px solid var(--accent-soft); outline-offset: 2px; }

canvas {
  display: block;
  width: 240px;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  margin-bottom: 16px;
}

footer { color: var(--muted); font-size: 0.88rem; padding-top: 12px; border-top: 1px solid var(--border); }
footer a { color: var(--accent); }
.copyright { margin-top: 16px; font-size: 0.82rem; }

[hidden] { display: none !important; }

/* SEO landing pages */
.crumbs { font-size: 0.9rem; color: var(--muted); margin-bottom: 18px; }
.crumbs a { color: var(--muted); text-decoration: none; }
.crumbs a:hover { color: var(--accent); }
.muted { color: var(--muted); font-size: 0.92rem; }
table.reqs { width: 100%; border-collapse: collapse; margin: 0 0 12px; }
table.reqs th, table.reqs td { text-align: left; vertical-align: top; padding: 12px 10px; border-bottom: 1px solid var(--border); }
table.reqs tr:last-child th, table.reqs tr:last-child td { border-bottom: 0; }
table.reqs th { width: 38%; font-weight: 650; }
table.reqs td { color: var(--muted); }
ol.steps { list-style: none; counter-reset: step; padding: 0; margin: 0 0 18px; }
ol.steps li { counter-increment: step; position: relative; padding-left: 44px; margin-bottom: 14px; }
ol.steps li::before {
  content: counter(step);
  position: absolute; left: 0; top: 0;
  width: 30px; height: 30px; border-radius: 50%;
  background: var(--accent-soft); color: var(--accent);
  display: grid; place-items: center; font-weight: 750; font-size: 0.9rem;
}
ul.plain { margin: 0 0 16px; padding-left: 22px; }
ul.plain li { margin-bottom: 8px; }
ul.formats { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
ul.formats li { border: 1px solid var(--border); border-radius: 12px; padding: 14px 16px; transition: border-color 0.15s, background 0.15s; }
ul.formats li:hover { border-color: var(--accent); background: var(--accent-soft); }
ul.formats a { font-weight: 650; margin-right: 6px; text-decoration: none; }
details { border-bottom: 1px solid var(--border); padding: 14px 0; }
details:last-child { border-bottom: 0; }
summary { cursor: pointer; font-weight: 650; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--accent); font-size: 1.3rem; line-height: 1; font-weight: 500; }
details[open] > summary::after { content: "–"; }
details p { margin: 10px 0 0; color: var(--muted); }
header .button { display: inline-block; text-decoration: none; padding: 13px 24px; font-size: 1.02rem; }
@media (max-width: 520px) { table.reqs th { width: 42%; } }

/* Usage by country */
.usage-detail { margin: 0 0 8px; color: var(--muted); font-size: 0.92rem; border: 0; padding: 0; }
.usage-detail summary { cursor: pointer; font-weight: 400; justify-content: flex-start; }
.usage-detail summary::after { content: none; }
.usage-detail ol { margin: 8px 0; padding-left: 22px; }
.usage-detail .hint { margin: 4px 0 0; }