:root {
  --bg: #ffffff;
  --bg-soft: #f6f7f9;
  --bg-code: #f2f3f6;
  --border: #e4e6eb;
  --border-strong: #d3d7de;
  --text: #15181e;
  --muted: #5c6470;
  --faint: #8b93a1;
  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-soft: #eef0ff;
  --ok: #0f6e56;
  --ok-soft: #e3f4ee;
  --warn: #a35a11;
  --radius: 12px;
  --radius-sm: 8px;
  --maxw: 1060px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

img { max-width: 100%; height: auto; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: saturate(180%) blur(8px);
  position: sticky;
  top: 0;
  z-index: 20;
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
  gap: 16px;
}
.logo {
  font-weight: 600;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}
.logo:hover { text-decoration: none; }
.logo-mark {
  width: 22px; height: 22px;
  border-radius: 6px;
  background: var(--accent);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 13px;
  font-weight: 700;
}
.site-nav { display: flex; gap: 20px; font-size: 14px; }
.site-nav a { color: var(--muted); }
.site-nav a:hover { color: var(--text); text-decoration: none; }
.site-nav a.active { color: var(--text); font-weight: 500; }

/* Hero */
.hero { padding: 56px 0 32px; }
.hero h1 {
  font-size: 36px;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin: 0 0 14px;
  font-weight: 600;
}
.hero p.lead { font-size: 18px; color: var(--muted); margin: 0 0 8px; max-width: 620px; }
.badges { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.badge {
  font-size: 13px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 4px 10px;
  border-radius: 999px;
}

/* Breadcrumb */
.crumbs { font-size: 13px; color: var(--faint); margin: 24px 0 4px; }
.crumbs a { color: var(--faint); }
.crumbs span { margin: 0 6px; }

/* Page head */
.page-head { padding: 8px 0 4px; }
.page-head h1 { font-size: 30px; line-height: 1.25; letter-spacing: -0.02em; margin: 0 0 10px; font-weight: 600; }
.page-head .sub { color: var(--muted); font-size: 17px; margin: 0; max-width: 700px; }

/* Tool card */
.tool {
  margin: 24px 0 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  padding: 20px;
}
.drop {
  border: 1.5px dashed var(--border-strong);
  border-radius: var(--radius);
  background: var(--bg-soft);
  padding: 34px 20px;
  text-align: center;
  transition: border-color .15s, background .15s;
  cursor: pointer;
}
.drop.hot { border-color: var(--accent); background: var(--accent-soft); }
.drop-title { font-size: 17px; font-weight: 500; margin: 0 0 4px; }
.drop-sub { font-size: 13px; color: var(--muted); margin: 0 0 14px; }

.btn {
  font: inherit;
  font-size: 15px;
  font-weight: 500;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
}
.btn:hover { background: var(--accent-hover); }
.btn.ghost { background: transparent; border-color: var(--border-strong); color: var(--text); }
.btn.ghost:hover { background: var(--bg-soft); }
.btn.small { font-size: 13px; padding: 6px 12px; }
.btn:disabled { opacity: .5; cursor: default; }

.opts {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  align-items: flex-end;
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
}
.field { display: flex; flex-direction: column; gap: 5px; }
.field label { font-size: 12px; font-weight: 500; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.field select, .field input[type="number"] {
  font: inherit;
  font-size: 14px;
  padding: 8px 10px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--text);
  min-width: 130px;
}
.field .hint { font-size: 12px; color: var(--faint); }

.privacy {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--ok);
  background: var(--ok-soft);
  border-radius: var(--radius-sm);
  padding: 9px 12px;
  margin-top: 18px;
}
.privacy svg { flex: none; }

.results { list-style: none; margin: 18px 0 0; padding: 0; display: grid; gap: 10px; }
.result {
  display: flex;
  align-items: center;
  gap: 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  background: var(--bg);
}
.result.thumb { width: 44px; height: 44px; border-radius: 6px; object-fit: cover; background: var(--bg-code); flex: none; }
.result .meta { flex: 1; min-width: 0; }
.result .name { font-size: 14px; font-weight: 500; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.result .dims { font-size: 12px; color: var(--muted); }
.result .delta { font-size: 12px; color: var(--ok); font-weight: 500; }
.result .delta.up { color: var(--warn); }
.result .err { font-size: 12px; color: #b42318; }

/* Content prose */
.prose { max-width: 760px; }
.prose h2 { font-size: 21px; margin: 40px 0 12px; font-weight: 600; letter-spacing: -0.01em; }
.prose h3 { font-size: 17px; margin: 26px 0 8px; font-weight: 600; }
.prose p { margin: 0 0 14px; color: #2b3038; }
.prose ul, .prose ol { margin: 0 0 16px; padding-left: 22px; color: #2b3038; }
.prose li { margin-bottom: 6px; }

/* Tool grid */
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 12px; margin: 18px 0 8px; }
.card {
  display: block;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 15px 16px;
  background: var(--bg);
  color: var(--text);
  transition: border-color .15s, box-shadow .15s;
}
.card:hover { border-color: var(--accent); text-decoration: none; box-shadow: 0 1px 3px rgba(16, 18, 24, .06); }
.card .t { font-size: 15px; font-weight: 500; margin: 0 0 3px; }
.card .d { font-size: 13px; color: var(--muted); margin: 0; }

.section { padding: 8px 0 20px; }
.section h2 { font-size: 20px; margin: 36px 0 6px; font-weight: 600; letter-spacing: -0.01em; }
.section .section-sub { color: var(--muted); margin: 0 0 6px; font-size: 15px; }

table.spec { width: 100%; border-collapse: collapse; margin: 10px 0 22px; font-size: 14px; }
table.spec th, table.spec td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
table.spec thead th { font-weight: 600; background: var(--bg-soft); }
table.spec tbody th { font-weight: 500; color: var(--muted); width: 26%; }

/* FAQ */
.faq { border-top: 1px solid var(--border); margin-top: 40px; padding-top: 20px; }
.faq details {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0;
  margin-bottom: 8px;
  background: var(--bg);
}
.faq summary {
  cursor: pointer;
  padding: 13px 16px;
  font-size: 15px;
  font-weight: 500;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; float: right; color: var(--faint); font-weight: 400; }
.faq details[open] summary::after { content: "\2013"; }
.faq .a { padding: 0 16px 14px; color: var(--muted); font-size: 15px; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 64px;
  padding: 28px 0 48px;
  font-size: 13px;
  color: var(--faint);
}
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; }
.site-footer a { color: var(--muted); }

.hidden { display: none !important; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

@media (max-width: 640px) {
  .hero { padding: 36px 0 22px; }
  .hero h1 { font-size: 28px; }
  .page-head h1 { font-size: 24px; }
  .site-nav { gap: 14px; }
  .site-nav a.hide-sm { display: none; }
  .tool { padding: 14px; }
  .drop { padding: 26px 14px; }
}