@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+JP:wght@300;400;500;700&family=IBM+Plex+Mono:wght@400;500&display=swap');
*{margin:0;padding:0;box-sizing:border-box}
:root{
  --bg:#f8f8fa;--surface:#fff;--surface-alt:#f0f0f4;
  --border:#ddd;--border-light:#e8e8ec;
  --text:#1a1a2e;--text-dim:#6e6e82;
  --accent:#4361ee;--accent-dim:rgba(67,97,238,0.08);--accent-glow:rgba(67,97,238,0.18);
  --success:#06d6a0;--danger:#ef476f;
}
:root[data-theme="dark"]{
  --bg:#08111e;--surface:#131c30;--surface-alt:#1c2741;
  --border:#1f2e4a;--border-light:#152038;
  --text:#d4dceb;--text-dim:#7d8ba2;
  --accent:#6cc7ff;--accent-dim:rgba(108,199,255,0.12);--accent-glow:rgba(108,199,255,0.28);
  --success:#3ddca3;--danger:#ff6b8a;
}
body{font-family:'IBM Plex Sans JP',sans-serif;background:var(--bg);color:var(--text);align-items:center}
.tool-hero{text-align:center;padding:44px 20px 20px}
.tool-hero h1{font-size:clamp(1.5rem,4.2vw,2.2rem);font-weight:700;letter-spacing:-0.02em}
.tool-hero h1 span{color:var(--accent)}
.tool-hero p{margin-top:8px;color:var(--text-dim);font-size:0.88rem;font-weight:300;line-height:1.7}
.container{width:100%;max-width:860px;padding:0 16px 80px}

.drop-zone{border:2px dashed var(--border);border-radius:12px;padding:44px 24px;text-align:center;cursor:pointer;transition:all .2s;background:var(--surface)}
.drop-zone:hover,.drop-zone.dragover{border-color:var(--accent);background:var(--accent-dim)}
.drop-zone-icon{font-size:2.4rem;margin-bottom:10px;display:block}
.drop-zone-text{font-size:0.9rem;color:var(--text-dim);line-height:1.8}
.drop-zone-text strong{color:var(--accent)}
.drop-zone-hint{font-size:0.74rem;color:var(--text-dim);margin-top:6px;opacity:0.6}
#fileInput{display:none}

.editor{display:none;margin-top:16px;animation:fadeUp .3s ease}
.editor.show{display:block}

.panel{background:var(--surface);border:1px solid var(--border-light);border-radius:10px;padding:18px 20px;margin-bottom:10px}
.panel-title{font-size:0.76rem;font-weight:700;color:var(--text-dim);text-transform:uppercase;letter-spacing:0.06em;margin-bottom:12px}
.panel-row{display:flex;flex-wrap:wrap;gap:14px;align-items:center}
.field{display:flex;flex-direction:column;gap:4px}
.field-label{font-size:0.76rem;color:var(--text-dim);font-weight:500}
.field-input{padding:7px 10px;border:1px solid var(--border);border-radius:6px;font-family:inherit;font-size:0.82rem;background:var(--surface);color:var(--text);outline:none;transition:border-color .2s}
.field-input:focus{border-color:var(--accent)}
select.field-input{cursor:pointer}

.opt-btns{display:flex;gap:5px}
.opt-btn{padding:6px 13px;border:1px solid var(--border);border-radius:6px;background:var(--surface-alt);color:var(--text-dim);font-family:inherit;font-size:0.76rem;cursor:pointer;transition:all .15s}
.opt-btn:hover{border-color:var(--accent);color:var(--text)}
.opt-btn.active{border-color:var(--accent);background:var(--accent-dim);color:var(--accent);font-weight:500}

.thumb-list{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px;max-height:320px;overflow-y:auto;padding:6px 0}
.thumb-item{position:relative;cursor:grab;transition:transform .15s,opacity .15s;user-select:none}
.thumb-item:active{cursor:grabbing}
.thumb-item.dragging{opacity:0.3;transform:scale(0.9)}
.thumb-item.drag-over{transform:scale(1.05)}
.thumb-img{width:80px;height:80px;border-radius:6px;object-fit:cover;border:1px solid var(--border-light);display:block;pointer-events:none}
.thumb-name{font-size:0.58rem;color:var(--text-dim);text-align:center;max-width:80px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;margin-top:2px;pointer-events:none}
.thumb-idx{position:absolute;top:2px;left:2px;background:var(--accent);color:#fff;font-size:0.58rem;font-weight:700;width:18px;height:18px;border-radius:4px;display:flex;align-items:center;justify-content:center;pointer-events:none}

.file-count{font-size:0.8rem;color:var(--text-dim);margin-top:6px}
.drag-hint{font-size:0.7rem;color:var(--text-dim);opacity:0.6;margin-top:4px}

.gen-row{display:flex;gap:8px;margin-top:12px;flex-wrap:wrap}
.gen-btn{flex:1;min-width:140px;padding:14px;border:none;border-radius:10px;font-family:inherit;font-size:0.92rem;font-weight:700;cursor:pointer;transition:all .2s;letter-spacing:-0.01em}
.gen-btn:hover{transform:translateY(-1px)}
.gen-btn:disabled{opacity:0.4;cursor:not-allowed;transform:none!important}
.gen-btn.primary{background:var(--accent);color:#fff;box-shadow:0 4px 16px var(--accent-glow)}
.gen-btn.secondary{background:var(--surface);color:var(--accent);border:1px solid var(--accent)}

.preview-section{display:none;margin-top:14px;animation:fadeUp .3s ease}
.preview-section.show{display:block}
.preview-label{font-size:0.76rem;font-weight:700;color:var(--text-dim);text-transform:uppercase;letter-spacing:0.06em;margin-bottom:8px}
.preview-wrap{background:var(--surface-alt);border:1px solid var(--border);border-radius:8px;padding:10px;overflow:auto;max-height:60vh;text-align:center}
.preview-wrap img,.preview-wrap canvas{max-width:100%;height:auto;border-radius:4px}
.pager{display:flex;align-items:center;justify-content:center;gap:10px;margin-top:10px}
.pager-btn{padding:6px 14px;border:1px solid var(--border);border-radius:6px;background:var(--surface);color:var(--text-dim);font-family:inherit;font-size:0.8rem;cursor:pointer;transition:all .15s}
.pager-btn:hover{border-color:var(--accent);color:var(--accent)}
.pager-btn:disabled{opacity:0.3;cursor:not-allowed}
.pager-info{font-size:0.8rem;color:var(--text-dim);font-variant-numeric:tabular-nums}

.error-msg{display:none;background:rgba(239,71,111,0.08);border:1px solid var(--danger);border-radius:8px;padding:12px 16px;margin-top:10px;color:var(--danger);font-size:0.84rem;text-align:center}
.error-msg.show{display:block;animation:fadeUp .3s ease}

.features{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,1fr));gap:8px;margin-top:28px}
.feature{background:var(--surface);border:1px solid var(--border-light);border-radius:8px;padding:12px 10px;text-align:center}
.feature:hover{border-color:var(--accent)}
.feature-icon{font-size:1rem;margin-bottom:4px;display:block}
.feature-text{font-size:0.68rem;color:var(--text-dim);line-height:1.5}

@keyframes fadeUp{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:600px){
  .panel-row{flex-direction:column;align-items:stretch}
  .gen-row{flex-direction:column}
}