/* =============================================================
   1. Tokens
   ============================================================= */
:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --ink: #16181d;
  --ink-soft: #565c66;
  --border: #e2e5ea;
  --accent: #2f6fed;
  --accent-ink: #ffffff;
  --success: #1f9d55;
  --danger: #d34848;
  --radius: 14px;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --display: "Manrope", var(--sans);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --container: 760px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101216;
    --surface: #191c22;
    --ink: #f2f3f5;
    --ink-soft: #a2a8b4;
    --border: #2b2f38;
    --accent: #5b8dff;
    --accent-ink: #0c1220;
  }
}

/* =============================================================
   2. Reset & base
   ============================================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; tab-size: 2; }
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  background: var(--bg);
  color: var(--ink);
  -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; line-height: 1.15; letter-spacing: -0.01em; font-family: var(--display); }
::selection { background: var(--accent); color: var(--accent-ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

/* =============================================================
   3. Utilities
   ============================================================= */
.container { max-width: var(--container); margin-inline: auto; padding-inline: 1.25rem; }
.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;
}
.skip-link:focus { top: 1rem; }

/* =============================================================
   4. Header / footer
   ============================================================= */
.site-header { padding-block: 1.1rem; border-bottom: 1px solid var(--border); }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.logo { display: flex; align-items: center; gap: .5rem; font-family: var(--display); font-weight: 800; font-size: 1.1rem; }
.logo-dot { color: var(--accent); }
.header-tag { font-size: .82rem; color: var(--ink-soft); font-weight: 500; }

.site-footer { border-top: 1px solid var(--border); padding-block: 2rem; margin-top: 3rem; color: var(--ink-soft); font-size: .9rem; }
.footer-inner { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; justify-content: space-between; }
.footer-links { display: flex; gap: 1.25rem; }
.footer-links a:hover { color: var(--ink); }

/* =============================================================
   5. Hero + tool card
   ============================================================= */
.hero { padding-block: 2.25rem 1.5rem; text-align: center; }
.hero h1 { font-size: clamp(1.6rem, 4.4vw, 2.3rem); }
.hero-sub { color: var(--ink-soft); max-width: 46ch; margin: .75rem auto 0; font-size: 1.02rem; }

.noscript-note {
  margin-top: 1.5rem; padding: .9rem 1.1rem; border: 1px solid var(--border);
  border-radius: 10px; background: var(--surface); color: var(--ink-soft); font-size: .92rem;
}

.tool-card {
  margin-top: 1.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: 0 1px 2px rgba(16,18,22,.04), 0 12px 28px -18px rgba(16,18,22,.18);
}
.tool-card .state { display: none; }
.tool-card[data-state="idle"] .state-idle,
.tool-card[data-state="loading-engine"] .state-loading-engine,
.tool-card[data-state="working"] .state-working,
.tool-card[data-state="done"] .state-done,
.tool-card[data-state="error"] .state-error { display: block; }

.dropzone {
  display: flex; flex-direction: column; align-items: center; gap: .5rem;
  padding: 2.25rem 1rem; border: 2px dashed var(--border); border-radius: calc(var(--radius) - 4px);
  cursor: pointer; color: var(--ink-soft); transition: border-color .18s var(--ease-out), background .18s var(--ease-out);
}
.dropzone:hover, .dropzone.is-dragover { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 6%, transparent); }
.dropzone-title { color: var(--ink); font-weight: 600; }
.dropzone-hint { font-size: .85rem; }

.state-loading-engine, .state-working { text-align: center; padding: 1.75rem 1rem; }
.state-title { font-weight: 700; margin-top: .9rem; }
.state-hint { color: var(--ink-soft); font-size: .9rem; margin-top: .25rem; }

.spinner {
  width: 34px; height: 34px; margin: 0 auto;
  border: 3px solid var(--border); border-top-color: var(--accent);
  border-radius: 50%; animation: spin 0.85s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.progress-bar { height: 6px; border-radius: 999px; background: var(--border); overflow: hidden; margin-top: 1rem; max-width: 280px; margin-inline: auto; }
.progress-fill { height: 100%; width: 5%; background: var(--accent); transition: width .25s var(--ease-out); }

.state-done { text-align: center; }
.result-preview { border-radius: calc(var(--radius) - 4px); overflow: hidden; border: 1px solid var(--border); }
.result-canvas-wrap {
  display: flex; align-items: center; justify-content: center;
  background: #fff; min-height: 180px; padding: .75rem;
}
.result-canvas-wrap.is-transparent-preview {
  background-image: conic-gradient(#e6e8ec 25%, transparent 0 50%, #e6e8ec 0 75%, transparent 0);
  background-size: 18px 18px;
}
#result-canvas { max-height: 360px; width: auto; max-width: 100%; }

.bg-choice { display: inline-flex; gap: .4rem; margin-top: 1rem; padding: .3rem; background: var(--bg); border-radius: 999px; border: 1px solid var(--border); }
.bg-opt { padding: .45rem 1rem; border-radius: 999px; font-size: .88rem; font-weight: 600; color: var(--ink-soft); }
.bg-opt.is-active { background: var(--accent); color: var(--accent-ink); }

.btn-download {
  display: block; width: 100%; margin-top: 1.1rem; padding: .95rem 1.25rem;
  background: var(--accent); color: var(--accent-ink); font-weight: 700; font-size: 1.02rem;
  border-radius: 10px; transition: transform .15s var(--ease-out), opacity .15s var(--ease-out);
}
.btn-download:hover { opacity: .92; }
.btn-reset { display: inline-block; margin-top: .85rem; font-size: .88rem; color: var(--ink-soft); text-decoration: underline; text-underline-offset: 3px; }
.btn-reset:hover { color: var(--ink); }

.state-error { text-align: center; padding: 1.25rem 1rem; }
.state-error .state-title { color: var(--danger); margin-top: 0; }

.privacy-badge { margin-top: 1.1rem; font-size: .9rem; color: var(--ink-soft); }
.limits-note { margin-top: .35rem; font-size: .82rem; color: var(--ink-soft); opacity: .85; }

/* =============================================================
   6. Ad slots
   ============================================================= */
.ad-slot {
  min-height: 90px; margin-block: 2rem; border: 1px dashed var(--border); border-radius: 10px;
  display: flex; align-items: center; justify-content: center; color: var(--ink-soft); font-size: .78rem;
}
.ad-label { text-transform: uppercase; letter-spacing: .08em; }

/* =============================================================
   7. How it works / SEO copy / FAQ
   ============================================================= */
.how { padding-block: 1rem 2rem; }
.how h2 { font-size: 1.4rem; margin-bottom: 1.25rem; }
.how-steps { list-style: none; display: grid; gap: 1.25rem; grid-template-columns: 1fr; }
.how-steps li { padding: 1.1rem; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); }
.how-steps svg { color: var(--accent); margin-bottom: .6rem; }
.how-steps h3 { font-size: 1.02rem; margin-bottom: .3rem; }
.how-steps p { color: var(--ink-soft); font-size: .92rem; }

.seo-copy { margin-top: 2rem; }
.seo-copy h2 { font-size: 1.25rem; margin-bottom: .75rem; }
.seo-copy p { color: var(--ink-soft); margin-bottom: .9rem; }

.faq { padding-block: 1rem 2.5rem; }
.faq h2 { font-size: 1.4rem; margin-bottom: 1rem; }
.faq details {
  border: 1px solid var(--border); border-radius: 10px; padding: .9rem 1.1rem; margin-bottom: .6rem; background: var(--surface);
}
.faq summary { cursor: pointer; font-weight: 600; }
.faq details p { color: var(--ink-soft); margin-top: .6rem; font-size: .94rem; }

/* =============================================================
   8. Responsive
   ============================================================= */
@media (min-width: 720px) {
  .how-steps { grid-template-columns: repeat(3, 1fr); }
}

/* =============================================================
   9. Reduced motion — only intrusive effects
   ============================================================= */
@media (prefers-reduced-motion: reduce) {
  .spinner { animation-duration: 1.6s; }
}