:root{
  --bg:#0d0f12;
  --panel:#15181d;
  --panel-2:#1b1f26;
  --line:#262b33;
  --txt:#e8ebef;
  --txt-dim:#9aa3af;
  --accent:#e2483a;
  --accent-soft:rgba(226,72,58,.16);
  --radius:12px;
  --font:"Inter","Segoe UI",system-ui,-apple-system,sans-serif;
  --font-title:"Barlow Semi Condensed","Inter","Segoe UI",system-ui,sans-serif;
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;font-family:var(--font);background:var(--bg);color:var(--txt);overflow:hidden;-webkit-font-smoothing:antialiased}
button{font-family:inherit;color:inherit}

#app{height:100vh;display:grid;grid-template-columns:1fr 372px;grid-template-rows:60px 1fr;grid-template-areas:"top top" "stage panel"}

/* ---------- top bar ---------- */
.topbar{grid-area:top;display:flex;align-items:center;justify-content:space-between;padding:0 18px;background:var(--panel);border-bottom:1px solid var(--line);z-index:5}
.brand{display:flex;align-items:center;gap:12px}
.brand svg{width:30px;height:30px;fill:none;stroke:var(--accent);stroke-width:1.7;stroke-linejoin:round}
.brand strong{display:block;font-family:var(--font-title);font-size:17px;font-weight:700;letter-spacing:.13em;text-transform:uppercase;line-height:1.1}
.brand span{display:block;font-size:11px;color:var(--txt-dim);letter-spacing:.06em}
.topbar-actions{display:flex;gap:8px}
.btn{border:0;background:var(--accent);color:#fff;padding:9px 16px;border-radius:8px;font-size:13px;font-weight:600;cursor:pointer;transition:.15s}
.btn:hover{filter:brightness(1.1)}
.btn.ghost{background:transparent;border:1px solid var(--line);color:var(--txt-dim);font-weight:500}
.btn.ghost:hover{border-color:#3b424e;color:var(--txt)}

/* ---------- stage ---------- */
.stage{grid-area:stage;position:relative;overflow:hidden;
  background:radial-gradient(120% 100% at 50% 0%,#2a3038 0%,#171a1f 45%,#0b0d10 100%)}
#viewport{position:absolute;inset:0}
#viewport canvas{display:block;width:100%;height:100%}
.hint{position:absolute;left:50%;bottom:14px;transform:translateX(-50%);white-space:nowrap;max-width:96%;overflow:hidden;font-size:11px;color:#6d757f;letter-spacing:.03em;pointer-events:none}

.viewtools{position:absolute;top:16px;left:16px;display:flex;align-items:center;gap:4px;padding:5px;background:rgba(16,19,23,.72);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.07);border-radius:10px}
.viewtools button{border:0;background:transparent;color:var(--txt-dim);font-size:12px;font-weight:500;padding:6px 11px;border-radius:7px;cursor:pointer;transition:.14s;display:flex;align-items:center}
.viewtools button:hover{background:rgba(255,255,255,.07);color:var(--txt)}
.viewtools button.active{background:var(--accent-soft);color:#ff8b7e}
.viewtools svg{width:17px;height:17px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linejoin:round}
.viewtools .sep{width:1px;height:18px;background:var(--line);margin:0 3px}

.loader{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:16px;background:rgba(11,13,16,.92);z-index:4;transition:opacity .5s}
.loader.done{opacity:0;pointer-events:none}
.loader p{font-size:13px;color:var(--txt-dim);letter-spacing:.04em}
.loader span{color:var(--txt);margin-left:8px;font-variant-numeric:tabular-nums}
.spin{width:34px;height:34px;border:2px solid var(--line);border-top-color:var(--accent);border-radius:50%;animation:sp .8s linear infinite}
@keyframes sp{to{transform:rotate(360deg)}}

/* ---------- panel ---------- */
.panel{grid-area:panel;background:var(--panel);border-left:1px solid var(--line);overflow:hidden;display:flex}
.panel-scroll{overflow-y:auto;padding:4px 20px 40px;width:100%;scrollbar-width:thin;scrollbar-color:#333a44 transparent}
.panel-scroll::-webkit-scrollbar{width:9px}
.panel-scroll::-webkit-scrollbar-thumb{background:#2c333d;border-radius:5px;border:3px solid var(--panel)}

.group{padding:20px 0;border-bottom:1px solid var(--line)}
.group:last-child{border-bottom:0}
.group h2{margin:0 0 12px;font-family:var(--font-title);font-size:14px;font-weight:600;letter-spacing:.17em;text-transform:uppercase;color:var(--txt)}
.group .sub{margin:-8px 0 12px;font-size:11.5px;color:var(--txt-dim)}
.subgroup{margin-top:16px}
.subgroup h3{margin:0 0 9px;font-size:11.5px;font-weight:500;color:var(--txt-dim);letter-spacing:.04em}

/* swatches */
.swatches{display:grid;grid-template-columns:repeat(9,1fr);gap:7px}
.swatches button{width:100%;aspect-ratio:1;border-radius:50%;border:2px solid transparent;box-shadow:inset 0 0 0 1px rgba(255,255,255,.14);cursor:pointer;padding:0;position:relative;transition:transform .12s}
.swatches button:hover{transform:scale(1.14)}
.swatches button.sel{border-color:var(--accent);box-shadow:inset 0 0 0 1px rgba(255,255,255,.2)}
.swatches button.custom{background:conic-gradient(#f44,#fd4,#4f6,#4df,#66f,#f4d,#f44);overflow:hidden}
.swatches button.custom input{position:absolute;inset:-20%;opacity:0;cursor:pointer;width:140%;height:140%}

/* cards */
.cards{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.card{background:var(--panel-2);border:1px solid var(--line);border-radius:var(--radius);padding:12px 10px;cursor:pointer;text-align:center;transition:.15s}
.card:hover{border-color:#3b434f}
.card.sel{border-color:var(--accent);background:var(--accent-soft)}
.card-visual{display:block;width:56px;height:56px;margin:0 auto 9px;border-radius:50%;background:#0e1114;box-shadow:inset 0 0 0 5px #17191d,0 2px 8px rgba(0,0,0,.4)}
.rim-plastic{background:radial-gradient(circle at 38% 32%,#4a4f56,#191c20 62%,#0d0f11)}
.rim-alu{background:conic-gradient(from 6deg,#e6ebf2 0deg 11deg,#20242a 11deg 45deg,#e6ebf2 45deg 56deg,#20242a 56deg 90deg,#e6ebf2 90deg 101deg,#20242a 101deg 135deg,#e6ebf2 135deg 146deg,#20242a 146deg 180deg,#e6ebf2 180deg 191deg,#20242a 191deg 225deg,#e6ebf2 225deg 236deg,#20242a 236deg 270deg,#e6ebf2 270deg 281deg,#20242a 281deg 315deg,#e6ebf2 315deg 326deg,#20242a 326deg 360deg)}
.rim-alu::after{content:"";display:block;width:18px;height:18px;margin:19px auto;border-radius:50%;background:#c7ced8}
.card-label{display:block;font-family:var(--font-title);font-size:14px;font-weight:600;letter-spacing:.04em}
.card-note{display:block;font-size:10.5px;color:var(--txt-dim);margin-top:2px}
#alu-tint{display:none}
#alu-tint.on{display:block}

/* range */
.range{display:grid;grid-template-columns:1fr auto;align-items:center;gap:6px 10px;margin-top:12px;font-size:11.5px;color:var(--txt-dim)}
.range input{grid-column:1/-1;-webkit-appearance:none;appearance:none;width:100%;height:3px;border-radius:3px;background:var(--line);outline:0}
.range input::-webkit-slider-thumb{-webkit-appearance:none;width:15px;height:15px;border-radius:50%;background:var(--accent);cursor:pointer;border:3px solid var(--panel);box-shadow:0 0 0 1px var(--accent)}
.range output{font-variant-numeric:tabular-nums;color:var(--txt);font-size:11.5px}

/* toggles */
.toggle{display:grid;grid-template-columns:38px 1fr;align-items:start;gap:12px;padding:10px 0;cursor:pointer}
.toggle input{display:none}
.track{width:38px;height:21px;border-radius:11px;background:#2b313a;position:relative;transition:.18s;margin-top:1px}
.knob{position:absolute;top:3px;left:3px;width:15px;height:15px;border-radius:50%;background:#8b939e;transition:.18s}
.toggle input:checked + .track{background:var(--accent)}
.toggle input:checked + .track .knob{left:20px;background:#fff}
.toggle-label{font-size:12.5px;line-height:1.35}
.toggle-label em{display:block;font-style:normal;font-size:11px;color:var(--txt-dim);margin-top:2px}

/* recap */
.recap ul{list-style:none;margin:0;padding:0;font-size:12px}
.recap li{font-variant-numeric:tabular-nums;display:flex;align-items:center;justify-content:space-between;padding:6px 0;border-bottom:1px dashed #21262e;color:var(--txt-dim)}
.recap li:last-child{border-bottom:0}
.recap b{color:var(--txt);font-weight:500;display:flex;align-items:center;gap:7px}
.recap i{width:11px;height:11px;border-radius:3px;box-shadow:inset 0 0 0 1px rgba(255,255,255,.2)}

/* toast */
.toast{position:fixed;bottom:26px;left:50%;transform:translate(-50%,20px);background:#22272f;border:1px solid var(--line);color:var(--txt);padding:10px 18px;border-radius:9px;font-size:12.5px;opacity:0;pointer-events:none;transition:.25s;z-index:50}
.toast.on{opacity:1;transform:translate(-50%,0)}

@media (max-width:1100px){
  #app{grid-template-columns:1fr;grid-template-rows:56px 1fr 45vh;grid-template-areas:"top" "stage" "panel"}
  .panel{border-left:0;border-top:1px solid var(--line)}
  .swatches{grid-template-columns:repeat(10,1fr)}
}