/* ==========================================================================
   1. Tokens
   ========================================================================== */
:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --ink: #171923;
  --ink-soft: #575c6b;
  --border: #e2e5ec;
  --accent: #2f6fed;
  --accent-ink: #ffffff;
  --accent-soft: #eaf0ff;
  --radius: 14px;
  --radius-sm: 9px;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --display: "Manrope", var(--sans);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --shadow: 0 1px 2px rgba(23,25,35,.04), 0 8px 24px -12px rgba(23,25,35,.12);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12131a;
    --surface: #1b1d27;
    --ink: #f1f2f6;
    --ink-soft: #a3a8b8;
    --border: #2c2f3d;
    --accent: #6d97ff;
    --accent-ink: #0d1120;
    --accent-soft: #232a45;
    --shadow: 0 1px 2px rgba(0,0,0,.3), 0 8px 24px -12px rgba(0,0,0,.5);
  }
}

/* ==========================================================================
   2. Reset
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; tab-size: 2; scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: clip;
}
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; background: none; }
a { color: inherit; text-decoration: none; }
p { text-wrap: pretty; }
h1, h2, h3 { text-wrap: balance; font-family: var(--display); line-height: 1.15; letter-spacing: -0.01em; }
::selection { background: var(--accent); color: var(--accent-ink); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: fixed; top: -100px; left: 1rem;
  padding: .6rem 1rem; background: var(--surface); color: var(--ink);
  z-index: 9999; border-radius: 8px; font-weight: 600; box-shadow: var(--shadow);
}
.skip-link:focus { top: 1rem; }

/* ==========================================================================
   3. Header / footer
   ========================================================================== */
.site-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem clamp(1rem, 4vw, 2.5rem);
  max-width: 900px; margin: 0 auto;
}
.brand {
  display: flex; align-items: center; gap: .5rem;
  font-family: var(--display); font-weight: 800; font-size: 1.05rem;
  color: var(--ink);
}
.brand svg { color: var(--accent); }
.site-nav a {
  font-size: .9rem; font-weight: 500; color: var(--ink-soft);
  transition: color .2s var(--ease-out);
}
.site-nav a:hover { color: var(--accent); }

.site-footer {
  display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; justify-content: space-between;
  padding: 2rem clamp(1rem, 4vw, 2.5rem) 3rem;
  max-width: 900px; margin: 0 auto;
  color: var(--ink-soft); font-size: .85rem;
  border-top: 1px solid var(--border); margin-top: 2rem;
}
.site-footer nav { display: flex; gap: 1.25rem; }
.site-footer a { color: var(--ink-soft); }
.site-footer a:hover { color: var(--accent); }

/* ==========================================================================
   4. Hero + tool card
   ========================================================================== */
.hero {
  max-width: 900px; margin: 0 auto;
  padding: .5rem clamp(1rem, 4vw, 2.5rem) 1.5rem;
  text-align: center;
}
.hero h1 { font-size: clamp(1.6rem, 4vw, 2.4rem); }
.subtitle {
  color: var(--ink-soft); margin: .6rem auto 1.75rem; max-width: 46ch;
  font-size: 1.02rem;
}

.tool-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.25rem;
  text-align: left;
}

.tabs {
  display: flex; flex-wrap: wrap; gap: .4rem;
  margin-bottom: 1.1rem;
}
.tab {
  padding: .5rem .9rem;
  border-radius: 999px;
  font-size: .88rem; font-weight: 600;
  color: var(--ink-soft);
  background: transparent;
  border: 1px solid var(--border);
  transition: background .2s var(--ease-out), color .2s var(--ease-out), border-color .2s var(--ease-out);
}
.tab:hover { color: var(--ink); }
.tab.is-active { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }

.tool-panel.is-hidden { display: none; }

.convert-row {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: .75rem;
  align-items: end;
}
@media (max-width: 539px) {
  .convert-row { grid-template-columns: 1fr; }
  .btn-swap { justify-self: center; transform: rotate(90deg); }
}

.field { display: flex; flex-direction: column; gap: .35rem; }
.field--full { grid-column: 1 / -1; }
.field label {
  font-size: .78rem; font-weight: 600; color: var(--ink-soft);
  text-transform: uppercase; letter-spacing: .03em;
}
.field input[type="number"],
.field output,
.field select {
  width: 100%;
  padding: .75rem .85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--ink);
  font-size: 1.05rem;
  font-weight: 600;
  font-family: var(--sans);
}
.field output { display: block; background: var(--accent-soft); border-color: transparent; color: var(--accent); }
.field select { font-weight: 500; font-size: .92rem; margin-top: .1rem; }
.field input:focus, .field select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }

.btn-swap {
  width: 42px; height: 42px;
  display: grid; place-items: center;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  border: 1px solid transparent;
  transition: transform .25s var(--ease-out), background .2s var(--ease-out);
  margin-bottom: .1rem;
}
.btn-swap:hover { background: var(--accent); color: var(--accent-ink); transform: rotate(180deg); }

.tabla-wrap { overflow-x: auto; margin-top: .25rem; }
.tabla-tallas { width: 100%; border-collapse: collapse; font-size: .92rem; }
.tabla-tallas th, .tabla-tallas td {
  padding: .55rem .7rem; text-align: center; border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
.tabla-tallas th { color: var(--ink-soft); font-size: .76rem; text-transform: uppercase; letter-spacing: .03em; }
.tabla-tallas tr:hover td { background: var(--accent-soft); }

.privacy-badge {
  margin-top: 1rem; font-size: .84rem; color: var(--ink-soft);
}

/* ==========================================================================
   5. Ad slots
   ========================================================================== */
.ad-slot {
  max-width: 900px; margin: 1.75rem auto; padding: clamp(1rem, 3vw, 1.5rem);
  min-height: 90px;
  border: 1px dashed var(--border); border-radius: var(--radius-sm);
  display: grid; place-items: center;
  color: var(--ink-soft); font-size: .78rem; letter-spacing: .04em; text-transform: uppercase;
}
.ad-slot__label { opacity: .6; }

/* ==========================================================================
   6. Content sections
   ========================================================================== */
.content-block {
  max-width: 760px; margin: 0 auto; padding: 1rem clamp(1rem, 4vw, 2.5rem) 2rem;
}
.content-block h2 { font-size: 1.3rem; margin-bottom: .75rem; margin-top: 1.75rem; }
.content-block h2:first-child { margin-top: 0; }
.content-block p { color: var(--ink-soft); margin-bottom: 1rem; }

.steps { list-style: none; display: grid; gap: .85rem; counter-reset: step; }
.steps li {
  padding-left: 2.4rem; position: relative; color: var(--ink-soft);
}
.steps li::before {
  counter-increment: step; content: counter(step);
  position: absolute; left: 0; top: 0;
  width: 1.7rem; height: 1.7rem; border-radius: 999px;
  background: var(--accent-soft); color: var(--accent);
  display: grid; place-items: center; font-weight: 700; font-size: .85rem;
}
.steps strong { color: var(--ink); }

.faq-list { display: grid; gap: .6rem; }
.faq-list details {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: .9rem 1.1rem;
}
.faq-list summary {
  cursor: pointer; font-weight: 600; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 1rem;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; font-size: 1.2rem; color: var(--accent); flex-shrink: 0; }
.faq-list details[open] summary::after { content: "–"; }
.faq-list p { margin: .6rem 0 0; }

.tools-grid { display: grid; gap: .75rem; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.tool-card-mini {
  display: flex; gap: .75rem; align-items: flex-start;
  padding: .9rem; border: 1px solid var(--border); border-radius: var(--radius-sm);
  background: var(--surface);
}
.tool-card-mini__icon { font-size: 1.3rem; }
.tool-card-mini strong { display: block; font-size: .92rem; }
.tool-card-mini p { color: var(--ink-soft); font-size: .82rem; margin: .15rem 0 0; }