:root{
  --bg:#f6f7f9;
  --card:#ffffff;
  --ink:#15181d;
  --ink-2:#4a5260;
  --ink-3:#767f8d;
  --line:#e3e7ec;
  --accent:#1f6feb;
  --accent-ink:#ffffff;
  --note:#2f6fd0;
  --good:#0f7a52;
  --good-bg:#e8f6ef;
  --radius:14px;
}

*{box-sizing:border-box}

html,body{margin:0;padding:0}

body{
  background:var(--bg);
  color:var(--ink);
  font:16px/1.6 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  -webkit-font-smoothing:antialiased;
  padding:0 16px 64px;
}

.site{max-width:920px;margin:0 auto;padding:32px 0 16px}
.site h1{font-size:30px;line-height:1.25;margin:0 0 6px;letter-spacing:-.02em}
.brand{margin:0 0 6px;font-size:14px;font-weight:600;letter-spacing:.02em}
.brand a{color:var(--accent);text-decoration:none}
.brand a:hover{text-decoration:underline}
.tagline{margin:0;color:var(--ink-2);font-size:16px}

.privacy{
  max-width:920px;margin:0 auto 20px;
  display:flex;gap:12px;align-items:flex-start;
  background:var(--good-bg);border:1px solid #c7e8d9;
  border-radius:var(--radius);padding:12px 16px;
  color:#0d5c3f;font-size:15px;
}
.privacy-mark{
  flex:0 0 auto;width:18px;height:18px;margin-top:3px;border-radius:50%;
  background:var(--good);position:relative;
}
.privacy-mark::after{
  content:"";position:absolute;left:5px;top:2.5px;width:5px;height:9px;
  border:solid #fff;border-width:0 2px 2px 0;transform:rotate(45deg);
}

main{max-width:920px;margin:0 auto}

.panel{
  background:var(--card);border:1px solid var(--line);
  border-radius:var(--radius);padding:20px;margin-bottom:18px;
}

/* drop zone */
.drop{position:relative;border:2px dashed #c8d0da;border-radius:var(--radius);
  background:#fbfcfd;padding:34px 20px;text-align:center;cursor:pointer;transition:.15s}
.drop:hover,.drop:focus-visible{border-color:var(--accent);background:#f2f7ff;outline:none}
.drop.is-over{border-color:var(--accent);background:#eaf2ff}
.file-input{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer}
.drop-icon{width:38px;height:30px;margin:0 auto 10px;border:2px solid #aab4c2;border-radius:5px;position:relative}
.drop-icon::after{content:"";position:absolute;left:50%;bottom:-11px;transform:translateX(-50%);
  border-left:6px solid transparent;border-right:6px solid transparent;border-top:9px solid #aab4c2}
.drop-main{margin:0;font-size:17px;font-weight:600}
.drop-sub{margin:6px 0 0;color:var(--ink-3);font-size:14px}

.status{margin:14px 0 0;min-height:22px;font-size:15px;color:var(--ink-2)}
.status.is-error{color:#b3261e}
.status.is-ok{color:var(--good)}

.progress{height:6px;background:#eef1f5;border-radius:99px;overflow:hidden;margin-top:10px}
.progress-bar{height:100%;width:0;background:var(--accent);transition:width .1s linear}

/* controls */
.controls{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:20px;
  padding-top:20px;border-top:1px solid var(--line)}
.ctrl-wide{grid-column:1/-1}
.ctrl label{display:block;font-size:14px;font-weight:600;margin-bottom:8px}
.ctrl output{float:right;color:var(--ink-3);font-weight:400}

input[type=range]{width:100%;height:32px;margin:0;accent-color:var(--accent)}
input[type=number],select{
  width:100%;min-height:42px;padding:8px 10px;font-size:16px;
  border:1px solid #ccd4de;border-radius:9px;background:#fff;color:var(--ink)
}
select{width:auto;min-width:90px}

.seg{display:flex;gap:8px}
.seg-btn{flex:1;min-height:42px;border:1px solid #ccd4de;background:#fff;border-radius:9px;
  font-size:15px;color:var(--ink-2);cursor:pointer}
.seg-btn.is-on{background:var(--accent);border-color:var(--accent);color:var(--accent-ink);font-weight:600}

.check{display:flex;align-items:center;gap:9px;font-size:15px;min-height:42px}
.check input{width:20px;height:20px;accent-color:var(--accent)}
.inline{display:flex;align-items:center;gap:8px;margin-top:10px;flex-wrap:wrap}
.inline-label{font-size:14px;font-weight:600;margin:0}

.hint{margin:7px 0 0;font-size:13px;color:var(--ink-3);line-height:1.5}

/* results */
.results{margin-top:20px;padding-top:20px;border-top:1px solid var(--line)}
.results-head{display:flex;flex-wrap:wrap;gap:14px;justify-content:space-between;align-items:flex-start}
.stat{margin:0;font-size:18px;font-weight:600}
.stat-sub{margin:4px 0 0;font-size:13px;color:var(--ink-3)}
.actions{display:flex;flex-wrap:wrap;gap:8px}
.btn{min-height:42px;padding:0 16px;border:1px solid #ccd4de;background:#fff;border-radius:9px;
  font-size:15px;color:var(--ink);cursor:pointer}
.btn:hover{background:#f3f6fa}
.btn-primary{background:var(--accent);border-color:var(--accent);color:var(--accent-ink);font-weight:600}
.btn-primary:hover{background:#1a5fd0}

.canvas-wrap{margin-top:18px}
.canvas-label{margin:0 0 6px;font-size:13px;color:var(--ink-3);font-weight:600}
canvas{display:block;width:100%;background:#fbfcfd;border:1px solid var(--line);border-radius:10px}

/* prose */
.prose h2{font-size:20px;margin:0 0 12px;letter-spacing:-.01em}
.prose h3{font-size:16px;margin:18px 0 6px}
.prose p{margin:0 0 12px;color:var(--ink-2)}
.prose p:last-child{margin-bottom:0}
.ticks{margin:0 0 12px;padding:0;list-style:none}
.ticks li{position:relative;padding-left:24px;margin-bottom:9px;color:var(--ink-2)}
.ticks li::before{content:"";position:absolute;left:6px;top:9px;width:6px;height:10px;
  border:solid var(--good);border-width:0 2px 2px 0;transform:rotate(45deg)}
.ticks.plain li::before{border-color:#9aa5b3}
.steps{margin:0 0 4px;padding-left:20px;color:var(--ink-2)}
.steps li{margin-bottom:8px}
.fine{font-size:13px;color:var(--ink-3)}
.faq h3{margin-top:16px}

.site-foot{max-width:920px;margin:8px auto 0;color:var(--ink-3);font-size:13px;text-align:center}
.foot-nav{display:flex;flex-wrap:wrap;justify-content:center;gap:18px;margin-top:10px}
.foot-nav a{color:var(--accent);text-decoration:none;min-height:32px;display:inline-flex;align-items:center}
.foot-nav a:hover{text-decoration:underline}

@media (max-width:640px){
  body{padding:0 12px 48px}
  .site{padding:22px 0 14px}
  .site h1{font-size:24px}
  .panel{padding:16px}
  .controls{grid-template-columns:1fr;gap:16px}
  .actions{width:100%}
  .btn{flex:1 1 auto;min-width:calc(50% - 4px)}
  .drop{padding:26px 14px}
}