/* =============================================================
   1. Tokens
   ============================================================= */
:root {
  --bg: #f7f8fb;
  --bg-elevated: #ffffff;
  --text: #14161f;
  --text-muted: #5b6072;
  --border: #e3e5ec;
  --accent: #3b62f6;
  --accent-2: #8b5cf6;
  --accent-contrast: #ffffff;
  --success: #16a34a;
  --danger: #dc2626;
  --gauge-track: #e5e7eb;
  --shadow: 0 12px 32px -12px rgba(20, 22, 31, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d0f18;
    --bg-elevated: #161927;
    --text: #f1f2f8;
    --text-muted: #9a9fb5;
    --border: #262a3d;
    --gauge-track: #262a3d;
    --shadow: 0 12px 40px -12px rgba(0, 0, 0, 0.55);
  }
}

/* =============================================================
   2. Reset & base
   ============================================================= */
*, *::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(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
  overscroll-behavior-y: none;
}
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, h4 { text-wrap: balance; line-height: 1.1; letter-spacing: -0.01em; }
ul { list-style: none; padding: 0; }
::selection { background: var(--accent); color: #fff; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

/* =============================================================
   3. Utilities
   ============================================================= */
.skip-link {
  position: fixed; top: -100px; left: 1rem;
  padding: .6rem 1rem; background: var(--accent); color: #fff;
  z-index: 9999; border-radius: 8px; font-weight: 600;
}
.skip-link:focus { top: 1rem; }

.container {
  width: 100%;
  max-width: 960px;
  margin-inline: auto;
  padding-inline: 1.25rem;
}

.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;
}

[data-reveal] { opacity: 0; transform: translateY(16px); transition: opacity .6s var(--ease-out), transform .6s var(--ease-out); }
[data-reveal].is-revealed { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  [data-reveal] { opacity: 1; transform: none; transition: none; }
}

/* =============================================================
   4. Typography
   ============================================================= */
.eyebrow { font-size: .8rem; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--accent); }
.h1 { font-size: clamp(1.9rem, 5vw, 3rem); font-weight: 800; max-width: 18ch; margin-inline: auto; text-align: center; }
.subtitle { font-size: clamp(1rem, 2vw, 1.15rem); color: var(--text-muted); max-width: 46ch; margin: .9rem auto 0; text-align: center; }
h2.section-title { font-size: clamp(1.4rem, 3vw, 1.9rem); font-weight: 750; margin-bottom: 1rem; }

/* =============================================================
   5. Components
   ============================================================= */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  padding: .85rem 1.6rem; border-radius: 999px; font-weight: 650; font-size: 1rem;
  transition: transform .2s var(--ease-out), box-shadow .2s var(--ease-out), opacity .2s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 10px 24px -8px rgba(59, 98, 246, .55);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 30px -8px rgba(59, 98, 246, .6); }
.btn-primary:active { transform: translateY(0); }
.btn-ghost { background: var(--bg-elevated); border: 1px solid var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn:disabled { opacity: .5; pointer-events: none; }

.badge {
  display: inline-flex; align-items: center; gap: .4rem;
  font-size: .82rem; color: var(--text-muted);
  background: var(--bg-elevated); border: 1px solid var(--border);
  padding: .4rem .75rem; border-radius: 999px;
}

.card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

/* =============================================================
   6. Sections
   ============================================================= */

/* --- Header --- */
.site-header {
  position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.site-header-inner {
  display: flex; align-items: center; justify-content: space-between;
  padding-block: .85rem;
}
.logo { display: inline-flex; align-items: center; gap: .5rem; font-weight: 800; font-size: 1.15rem; }
.logo-mark {
  width: 30px; height: 30px; border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: grid; place-items: center; color: #fff; font-size: 1rem;
}
.header-nav { display: flex; align-items: center; gap: 1rem; font-size: .92rem; color: var(--text-muted); }

/* --- Hero + tool --- */
.hero { padding-block: clamp(2rem, 5vw, 3.5rem) 1rem; }

.tool-card { padding: clamp(1.25rem, 4vw, 2.25rem); margin-top: 1.75rem; }

.tool-stage { display: grid; place-items: center; gap: 1.1rem; text-align: center; }

.gauge-wrap { position: relative; width: min(100%, 340px); aspect-ratio: 5 / 3.1; }
.gauge-wrap canvas { width: 100%; height: 100%; }

.readout { display: flex; align-items: baseline; justify-content: center; gap: .4rem; }
.readout-value { font-size: clamp(2.2rem, 8vw, 3.2rem); font-weight: 800; font-variant-numeric: tabular-nums; }
.readout-unit { font-size: 1rem; color: var(--text-muted); font-weight: 600; }
.phase-label { font-size: .95rem; color: var(--text-muted); min-height: 1.4em; }

.tool-idle-copy { max-width: 34ch; color: var(--text-muted); font-size: .95rem; }

.results-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: .75rem;
  width: 100%; margin-top: .5rem;
}
.result-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: .9rem .5rem;
  text-align: center;
}
.result-item .result-label { display: block; font-size: .74rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: .06em; margin-bottom: .25rem; }
.result-item .result-value { font-size: clamp(1.3rem, 4vw, 1.7rem); font-weight: 800; font-variant-numeric: tabular-nums; }
.result-item .result-unit { font-size: .78rem; color: var(--text-muted); }

.result-actions { display: flex; flex-wrap: wrap; gap: .6rem; justify-content: center; margin-top: .5rem; }

.error-box {
  color: var(--danger); font-size: .92rem; max-width: 40ch; text-align: center;
}

.privacy-badge { display: flex; flex-direction: column; align-items: center; gap: .4rem; margin-top: 1.4rem; text-align: center; }
.privacy-badge .badge { max-width: 42ch; text-align: left; }
.limits-note { font-size: .82rem; color: var(--text-muted); text-align: center; }

/* state visibility */
.tool-card [data-state-view] { display: none; }
.tool-card[data-state="idle"] [data-state-view="idle"] { display: grid; }
.tool-card[data-state="running"] [data-state-view="running"] { display: grid; }
.tool-card[data-state="done"] [data-state-view="done"] { display: grid; }
.tool-card[data-state="error"] [data-state-view="error"] { display: grid; }
.tool-card:not([data-state]) [data-state-view="idle"] { display: grid; }

/* --- Ad slots --- */
.ad-slot {
  min-height: 90px;
  display: flex; align-items: center; justify-content: center;
  border: 1px dashed var(--border); border-radius: var(--radius-md);
  color: var(--text-muted); font-size: .8rem; text-transform: uppercase; letter-spacing: .08em;
  margin-block: 1.75rem;
}

/* --- How it works --- */
.how-grid { display: grid; gap: 1.25rem; grid-template-columns: 1fr; }
.how-step { display: flex; gap: 1rem; align-items: flex-start; }
.how-step-num {
  flex: none; width: 34px; height: 34px; border-radius: 50%;
  background: var(--bg); border: 1px solid var(--border);
  display: grid; place-items: center; font-weight: 700; color: var(--accent);
}
.how-step h3 { font-size: 1.02rem; margin-bottom: .3rem; }
.how-step p { color: var(--text-muted); font-size: .94rem; }

/* --- SEO text --- */
.seo-text { color: var(--text-muted); font-size: .98rem; }
.seo-text p { margin-bottom: 1rem; }
.seo-text h2 { color: var(--text); }

/* --- FAQ --- */
.faq-item {
  border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: .9rem 1.1rem; margin-bottom: .6rem; background: var(--bg-elevated);
}
.faq-item summary { cursor: pointer; font-weight: 650; list-style: none; display: flex; justify-content: space-between; gap: 1rem; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; color: var(--accent); font-size: 1.2rem; }
.faq-item[open] summary::after { content: "\2212"; }
.faq-item p { margin-top: .6rem; color: var(--text-muted); font-size: .94rem; }

/* --- History --- */
.history-empty { color: var(--text-muted); font-size: .9rem; }
.history-table { width: 100%; border-collapse: collapse; font-size: .88rem; }
.history-table th, .history-table td { padding: .5rem .4rem; text-align: left; border-bottom: 1px solid var(--border); }
.history-table th { color: var(--text-muted); font-weight: 600; font-size: .78rem; text-transform: uppercase; }

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 3rem; padding-block: 2rem;
  color: var(--text-muted); font-size: .85rem;
}
.footer-links { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: .75rem; }
.footer-links a:hover { color: var(--accent); }

/* section rhythm */
.section { padding-block: clamp(1.5rem, 4vw, 2.5rem); }

/* =============================================================
   7. Effects
   ============================================================= */
@keyframes spin { to { transform: rotate(360deg); } }

/* =============================================================
   8. Responsive
   ============================================================= */
@media (min-width: 540px) {
  .how-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (min-width: 720px) {
  .container { padding-inline: 2rem; }
}
@media (min-width: 960px) {
  .h1 { max-width: 22ch; }
}

/* =============================================================
   9. Reduced-motion (only intrusive effects)
   ============================================================= */
@media (prefers-reduced-motion: reduce) {
  .btn-primary:hover { transform: none; }
}