:root{
  --bg:#f4f6fb; --card:#ffffffd9; --line:#0f1c3320; --txt:#1a2436; --dim:#5b6b83;
  --acc1:#0ea5a0; --acc2:#6d5ce7; --grad:linear-gradient(120deg,var(--acc1),var(--acc2));
  --ok:#14934c; --warn:#b45309;
}
*{box-sizing:border-box}
[hidden]{display:none !important}
html,body{margin:0}
body{
  font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Segoe UI",Roboto,sans-serif;
  background:var(--bg); color:var(--txt); min-height:100vh; display:flex; flex-direction:column;
  background-image:
    radial-gradient(60rem 30rem at 15% -10%, #6d5ce71a, transparent 60%),
    radial-gradient(50rem 28rem at 90% 10%, #0ea5a017, transparent 60%);
  background-attachment:fixed;
}
a{color:var(--acc1)}
kbd{background:#ffffff;border:1px solid var(--line);border-radius:6px;padding:1px 6px;font:inherit;font-size:.85em;box-shadow:0 1px 0 #0f1c3320}

.site-head{display:flex;justify-content:space-between;align-items:center;padding:18px 28px;max-width:1240px;margin:0 auto;width:100%}
.brand{display:flex;align-items:center;gap:10px;font-size:20px;font-weight:700;letter-spacing:.5px}
.brand em{font-style:normal;font-weight:400;font-size:13px;color:var(--dim)}
.privacy{font-size:12.5px;color:var(--dim);border:1px solid var(--line);padding:6px 12px;border-radius:99px;background:#ffffffb0}

main{flex:1;width:100%;max-width:1240px;margin:0 auto;padding:0 28px 40px}
footer{text-align:center;color:var(--dim);font-size:12.5px;padding:18px;border-top:1px solid var(--line);background:#ffffff90}

/* hero */
.hero{max-width:760px;margin:40px auto 0;text-align:center}
.hero h1{font-size:clamp(30px,5vw,46px);line-height:1.25;margin:0 0 14px}
.hero h1 span{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p{color:var(--dim);line-height:1.9;margin:0 0 26px}
.dropzone{
  border:1.5px dashed #0f1c3333;border-radius:20px;padding:44px 24px 34px;cursor:pointer;
  transition:.2s;background:#ffffffa8;outline:none;
}
.dropzone:hover,.dropzone:focus-visible,body.dragging .dropzone{border-color:var(--acc1);background:#0ea5a00d;box-shadow:0 0 0 4px #0ea5a014}
body.dragging::after{content:"松开即压缩";position:fixed;inset:0;display:grid;place-items:center;font-size:26px;font-weight:700;background:#f4f6fbe8;z-index:50;pointer-events:none}
.dz-icon{color:var(--acc1);margin-bottom:8px}
.dz-title{font-size:18px;font-weight:600}
.dz-sub{color:var(--dim);font-size:13px;margin:6px 0 16px}
.points{list-style:none;margin:26px 0 0;padding:0;display:grid;gap:9px;text-align:left;color:var(--dim);font-size:14px}
.points li::before{content:"●";color:var(--acc2);margin-right:9px;font-size:9px;vertical-align:2px}
.points b{color:var(--txt)}

/* workspace */
.work{display:grid;grid-template-columns:minmax(0,1.45fr) minmax(320px,.85fr);gap:22px;margin-top:26px}
@media(max-width:900px){.work{grid-template-columns:1fr}}
.panel{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:18px;backdrop-filter:blur(8px);box-shadow:0 4px 24px #14243f0d}
.preview{position:relative;height:min(52vh,520px);border-radius:12px;overflow:hidden;background:
  repeating-conic-gradient(#0f1c330d 0 25%, transparent 0 50%) 0 0/22px 22px; border:1px solid var(--line)}
.preview img{position:absolute;inset:0;width:100%;height:100%;object-fit:contain;display:block}
.preview img.overlay{clip-path:inset(0 50% 0 0)}
.tag{position:absolute;bottom:10px;font-size:11px;padding:3px 9px;border-radius:99px;background:#ffffffd9;border:1px solid var(--line);letter-spacing:1px;pointer-events:none}
.tag-l{left:10px;color:var(--warn)}.tag-r{right:10px;color:var(--acc1)}
.busy{position:absolute;top:10px;left:50%;transform:translateX(-50%);font-size:12px;background:#ffffffee;border:1px solid var(--line);padding:5px 14px;border-radius:99px;animation:pulse 1.2s infinite}
@keyframes pulse{50%{opacity:.55}}
.split-row{display:flex;align-items:center;gap:12px;font-size:12px;color:var(--dim);margin:12px 2px 2px}
.split-row span{flex:1}
input[type=range]{width:100%;accent-color:var(--acc1)}
.stats{display:flex;flex-wrap:wrap;gap:10px;margin-top:14px}
.stat{flex:1;min-width:120px;background:#ffffffcc;border:1px solid var(--line);border-radius:12px;padding:10px 14px}
.stat span{display:block;font-size:11px;color:var(--dim);letter-spacing:1px}
.stat b{font-size:19px}
.stat b.ok{color:var(--ok)}.stat b.warn{color:var(--warn)}
.stat i{display:block;font-style:normal;font-size:11.5px;color:var(--dim);margin-top:2px}

/* controls */
.ctrl-panel h2{font-size:13px;letter-spacing:2px;color:var(--dim);margin:2px 0 12px;font-weight:600}
.ctrl-panel h2:not(:first-child){margin-top:24px}
.row{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-bottom:12px;font-size:14px}
.row.col{display:grid;gap:6px}
.row.col span{display:flex;justify-content:space-between}
.row output{color:var(--acc1);font-variant-numeric:tabular-nums}
select{background:#ffffff;color:var(--txt);border:1px solid var(--line);border-radius:9px;padding:8px 10px;font:inherit;min-width:170px}
.hint{font-size:12.5px;color:var(--dim);line-height:1.7;margin:2px 0 8px;background:#0ea5a00c;border:1px solid #0ea5a02b;border-radius:10px;padding:10px 12px}
.actions{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.btn{border:1px solid var(--line);background:#ffffff;color:var(--txt);border-radius:11px;padding:11px 14px;font:inherit;font-size:14px;cursor:pointer;transition:.15s;box-shadow:0 1px 2px #14243f0a}
.btn:hover{border-color:#0f1c3340;background:#f8fafd}
.btn:active{transform:translateY(1px)}
.btn.primary{background:var(--grad);color:#ffffff;font-weight:700;border:none;box-shadow:0 2px 10px #6d5ce73d}
.btn.primary:hover{filter:brightness(1.06)}
.btn.ghost{background:transparent;box-shadow:none}
textarea{width:100%;height:74px;margin-top:12px;resize:vertical;background:#ffffff;border:1px solid var(--line);border-radius:10px;color:var(--dim);font:12px/1.6 ui-monospace,SFMono-Regular,Menlo,monospace;padding:9px 11px}
textarea:focus{outline:none;border-color:var(--acc2)}
.fineprint{font-size:12px;color:var(--dim);line-height:1.75;margin:10px 2px 0}
.fineprint b{color:var(--txt)}
code{background:#0f1c3312;padding:1px 5px;border-radius:5px;font-size:.92em}

/* toast */
.toast{position:fixed;left:50%;bottom:34px;transform:translateX(-50%);background:#1a2436f2;color:#fff;border-radius:12px;padding:11px 20px;font-size:14px;box-shadow:0 8px 30px #14243f33;z-index:99;animation:up .25s ease}
@keyframes up{from{opacity:0;transform:translate(-50%,8px)}}