:root{
    --ink:#0f172a;
    --muted:#64748b;
    --faint:#94a3b8;
    --line:#e5e9f0;
    --panel:rgba(255,255,255,.72);
    --panel-solid:#ffffff;
    --page:#f8fafc;
    --page2:#eef2f9;
    --blue:#3b82f6;
    --blue2:#60a5fa;
    --cyan:#22d3ee;
    --green:#22c55e;
    --red:#ef4444;
    --radius:14px;
    --shadow:0 8px 30px rgba(15,23,42,.06);
  }
  html[data-theme="dark"]{
    --ink:#e6ebf5;
    --muted:#98a2b8;
    --faint:#6b7488;
    --line:#2a3242;
    --panel:rgba(24,28,40,.6);
    --panel-solid:#161a26;
    --page:#0b0e16;
    --page2:#11141f;
    --shadow:0 8px 30px rgba(0,0,0,.35);
  }
  *{box-sizing:border-box;}
  body{
    margin:0;
    font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;
    background:linear-gradient(160deg,var(--page),var(--page2));
    color:var(--ink);
    min-height:100vh;
    transition:background .3s ease, color .3s ease;
  }
  .wrap{max-width:1080px;margin:0 auto;padding:24px 20px 60px;}

  /* header */
  header{display:flex;align-items:center;justify-content:space-between;padding-bottom:22px;border-bottom:1px solid var(--line);margin-bottom:28px;gap:12px;flex-wrap:wrap;}
  .brand{display:flex;align-items:center;gap:12px;}
  .logo{
    width:38px;height:38px;border-radius:10px;flex-shrink:0;
    background:linear-gradient(135deg,var(--blue),var(--cyan));
    display:flex;align-items:center;justify-content:center;color:#fff;
  }
  .brand-name{font-weight:700;font-size:14.5px;line-height:1.3;}
  .brand-sub{font-size:12px;color:var(--muted);}
  .header-right{display:flex;align-items:center;gap:16px;}
  .nav-note{font-size:12.5px;color:var(--muted);}
  @media (max-width:600px){ .nav-note{display:none;} }

  .portfolio-btn{
    font-size:12.5px;font-weight:700;color:#fff;text-decoration:none;
    background:linear-gradient(90deg,var(--blue),var(--cyan));
    padding:9px 16px;border-radius:9px;white-space:nowrap;flex-shrink:0;
    box-shadow:0 4px 14px rgba(59,130,246,.3);
    transition:transform .12s ease, filter .15s ease;
  }
  .portfolio-btn:hover{filter:brightness(1.06);}
  .portfolio-btn:active{transform:scale(.96);}
  @media (max-width:600px){ .portfolio-btn{padding:8px 12px;font-size:12px;} }

  .theme-toggle{
    width:38px;height:38px;border-radius:10px;border:1px solid var(--line);
    background:var(--panel-solid);color:var(--ink);cursor:pointer;
    display:flex;align-items:center;justify-content:center;flex-shrink:0;
    transition:transform .2s ease;
  }
  .theme-toggle:active{transform:scale(.9);}
  .theme-toggle svg{width:17px;height:17px;}

  /* badge */
  .badge{
    display:inline-flex;align-items:center;gap:7px;
    border:1px solid var(--line);border-radius:999px;
    padding:5px 12px;font-size:12px;color:var(--muted);margin-bottom:18px;
    background:var(--panel-solid);
  }
  .dot{width:6px;height:6px;border-radius:50%;background:var(--green);box-shadow:0 0 0 3px rgba(34,197,94,.18);}

  h1{font-size:36px;line-height:1.18;margin:0 0 12px;font-weight:800;letter-spacing:-0.5px;}
  h1 .grad{background:linear-gradient(90deg,var(--blue),var(--cyan));-webkit-background-clip:text;background-clip:text;color:transparent;}
  .lede{color:var(--muted);font-size:14.5px;max-width:620px;line-height:1.55;margin-bottom:32px;}

  /* main grid */
  .grid{display:grid;grid-template-columns:1fr 1fr;gap:22px;}
  @media (max-width:820px){.grid{grid-template-columns:1fr;}}

  .panel{
    background:var(--panel);
    backdrop-filter:blur(16px) saturate(160%);
    -webkit-backdrop-filter:blur(16px) saturate(160%);
    border:1px solid var(--line);border-radius:var(--radius);
    padding:22px;box-shadow:var(--shadow);
    transition:border-color .3s ease, background .3s ease;
  }
  .panel h2{font-size:14.5px;margin:0 0 4px;font-weight:700;}
  .panel .hint{font-size:12px;color:var(--muted);margin:0 0 14px;}

  .drop-zone{position:relative;}
  .drop-zone.dragover textarea{border-color:var(--blue2);box-shadow:0 0 0 4px rgba(96,165,250,.18);}
  .drop-hint{
    position:absolute;inset:0;display:none;align-items:center;justify-content:center;
    background:rgba(59,130,246,.08);border:2px dashed var(--blue2);border-radius:10px;
    font-size:13px;color:var(--blue);font-weight:600;pointer-events:none;
  }
  .drop-zone.dragover .drop-hint{display:flex;}

  textarea{
    width:100%;min-height:150px;resize:vertical;
    border:1px solid var(--line);border-radius:10px;
    padding:12px 14px;font-size:13px;color:var(--ink);
    font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
    outline:none;background:var(--panel-solid);
    transition:box-shadow .2s ease, border-color .2s ease;
  }
  textarea:focus{
    border-color:transparent;
    box-shadow:0 0 0 2px var(--panel-solid), 0 0 0 4px var(--blue2), 0 0 22px rgba(34,211,238,.35);
  }
  textarea::placeholder{color:var(--faint);}

  .input-toolbar{display:flex;justify-content:space-between;align-items:center;margin-top:8px;gap:8px;flex-wrap:wrap;}
  .csv-btn{
    font-size:11.5px;border:1px solid var(--line);background:var(--panel-solid);border-radius:7px;
    padding:6px 11px;cursor:pointer;color:var(--muted);display:flex;align-items:center;gap:6px;
  }
  .csv-btn:hover{color:var(--ink);border-color:var(--blue2);}

  .mode-toggle{display:flex;gap:10px;margin:18px 0 18px;}
  .mode-btn{
    flex:1;padding:12px 0;border-radius:10px;border:1px solid var(--line);
    background:var(--panel-solid);color:var(--ink);font-size:13.5px;font-weight:600;cursor:pointer;
    transition:all .15s ease;
  }
  .mode-btn.active{
    background:linear-gradient(90deg,var(--blue),var(--blue2));
    color:#fff;border-color:transparent;
    box-shadow:0 4px 14px rgba(59,130,246,.35);
  }

  .field-row{display:flex;gap:16px;margin-bottom:16px;flex-wrap:wrap;}
  .field{flex:1;min-width:120px;}
  .field label{display:block;font-size:12px;color:var(--muted);margin-bottom:6px;}
  .color-input{
    display:flex;align-items:center;gap:8px;
    border:1px solid var(--line);border-radius:10px;padding:8px 10px;background:var(--panel-solid);
  }
  .color-input input[type=color]{
    width:22px;height:22px;border:none;padding:0;background:none;cursor:pointer;border-radius:5px;overflow:hidden;
  }
  .color-input span{font-size:12.5px;color:var(--muted);font-family:ui-monospace,monospace;}

  select{
    width:100%;border:1px solid var(--line);border-radius:10px;padding:9px 10px;
    background:var(--panel-solid);color:var(--ink);font-size:12.5px;outline:none;
  }

  .size-row{margin-bottom:20px;}
  .size-row label{display:block;font-size:12px;color:var(--muted);margin-bottom:8px;}
  input[type=range]{width:100%;accent-color:var(--blue);}

  .actions{display:flex;align-items:center;gap:16px;flex-wrap:wrap;}
  .btn-primary{
    background:linear-gradient(90deg,var(--blue),var(--blue2));
    color:#fff;border:none;padding:12px 26px;border-radius:10px;
    font-size:13.5px;font-weight:700;cursor:pointer;
    box-shadow:0 4px 14px rgba(59,130,246,.35);
    transition:transform .12s ease, filter .15s ease;
  }
  .btn-primary:hover{filter:brightness(1.06);}
  .btn-primary:active{transform:scale(.97);}
  .btn-primary:disabled{opacity:.6;cursor:not-allowed;}
  .btn-clear{background:none;border:none;color:var(--muted);font-size:13.5px;cursor:pointer;font-weight:500;padding:12px 4px;}
  .btn-clear:hover{color:var(--ink);}
  .btn-zip{
    background:var(--panel-solid);border:1px solid var(--line);color:var(--ink);
    padding:12px 20px;border-radius:10px;font-size:13.5px;font-weight:600;cursor:pointer;
    display:flex;align-items:center;gap:8px;transition:border-color .15s ease;
  }
  .btn-zip:hover{border-color:var(--blue2);}
  .btn-zip:disabled{opacity:.5;cursor:not-allowed;}

  /* live preview strip */
  .live-preview{
    display:flex;align-items:center;gap:12px;margin-top:18px;padding:12px;
    border:1px solid var(--line);border-radius:10px;background:var(--panel-solid);
    min-height:0;
  }
  .live-preview.empty{display:none;}
  .live-preview .lp-canvas{width:56px;height:56px;display:flex;align-items:center;justify-content:center;flex-shrink:0;}
  .live-preview .lp-canvas canvas, .live-preview .lp-canvas img{max-width:100%;max-height:100%;}
  .live-preview .lp-text{font-size:11.5px;color:var(--muted);}
  .live-preview .lp-text b{color:var(--ink);font-size:12px;}

  /* preview panel */
  .preview-box{
    min-height:340px;border:1px dashed var(--line);border-radius:10px;
    display:flex;align-items:center;justify-content:center;flex-direction:column;
    gap:8px;color:var(--muted);
  }
  .preview-icon{
    width:42px;height:42px;border-radius:10px;
    background:linear-gradient(135deg,var(--blue),var(--cyan));
    display:flex;align-items:center;justify-content:center;color:#fff;margin-bottom:4px;
  }
  .preview-box p{margin:0;font-size:13px;}
  .preview-box .sub{font-size:12px;color:var(--faint);}

  .preview-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:4px;}

  .results-grid{
    display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));
    gap:14px;
  }
  .result-card{
    border:1px solid var(--line);border-radius:10px;padding:12px;text-align:center;
    background:var(--panel-solid);
    animation:fadeUp .38s ease both;
    transition:transform .18s ease, box-shadow .18s ease;
  }
  .result-card:hover{transform:translateY(-4px);box-shadow:0 10px 24px rgba(15,23,42,.12);}
  .result-card.error-card{border-color:rgba(239,68,68,.4);}
  @keyframes fadeUp{
    from{opacity:0;transform:translateY(10px);}
    to{opacity:1;transform:translateY(0);}
  }
  .result-card canvas, .result-card svg, .result-card img{max-width:100%;height:auto;}
  .result-card .val{
    font-size:11px;color:var(--muted);margin:8px 0 8px;word-break:break-all;
    font-family:ui-monospace,monospace;
  }
  .card-btns{display:flex;gap:6px;justify-content:center;flex-wrap:wrap;}
  .dl-btn{
    font-size:11px;border:1px solid var(--line);background:var(--panel-solid);border-radius:7px;
    padding:5px 9px;cursor:pointer;color:var(--ink);
  }
  .dl-btn:hover{background:var(--line);}

  .error-tag{
    display:flex;flex-direction:column;align-items:center;gap:6px;padding:14px 6px;color:var(--red);
  }
  .error-tag svg{width:22px;height:22px;}
  .error-tag span{font-size:10.5px;color:var(--red);}

  /* skeleton */
  .skeleton-card{
    border:1px solid var(--line);border-radius:10px;padding:12px;background:var(--panel-solid);
  }
  .skeleton-box{
    width:100%;aspect-ratio:1;border-radius:8px;
    background:linear-gradient(90deg, var(--line) 25%, rgba(148,163,184,.25) 37%, var(--line) 63%);
    background-size:400% 100%;
    animation:shimmer 1.2s ease infinite;
  }
  .skeleton-line{
    height:9px;border-radius:5px;margin-top:10px;
    background:linear-gradient(90deg, var(--line) 25%, rgba(148,163,184,.25) 37%, var(--line) 63%);
    background-size:400% 100%;
    animation:shimmer 1.2s ease infinite;
  }
  @keyframes shimmer{
    0%{background-position:100% 0;}
    100%{background-position:0 0;}
  }

  /* history */
  .history-section{margin-top:16px;}
  .history-title{font-size:11.5px;color:var(--muted);margin:0 0 8px;font-weight:600;text-transform:uppercase;letter-spacing:.03em;}
  .history-list{display:flex;flex-direction:column;gap:6px;max-height:120px;overflow-y:auto;}
  .history-item{
    display:flex;justify-content:space-between;align-items:center;gap:8px;
    border:1px solid var(--line);border-radius:8px;padding:7px 10px;font-size:11.5px;
    background:var(--panel-solid);cursor:pointer;color:var(--muted);
  }
  .history-item:hover{border-color:var(--blue2);color:var(--ink);}
  .history-item b{color:var(--ink);font-weight:600;}
  .history-empty{font-size:11.5px;color:var(--faint);}

  /* feature cards */
  .features{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:26px;}
  @media (max-width:820px){.features{grid-template-columns:1fr 1fr;}}
  @media (max-width:480px){.features{grid-template-columns:1fr;}}
  .feature{
    background:var(--panel);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
    border:1px solid var(--line);border-radius:var(--radius);
    padding:18px;
  }
  .feature h3{font-size:13.5px;margin:0 0 6px;font-weight:700;}
  .feature p{font-size:12.5px;color:var(--muted);margin:0;line-height:1.5;}

  footer{text-align:center;margin-top:44px;padding-top:22px;border-top:1px solid var(--line);
    font-size:12px;color:var(--faint);}
  footer span{color:var(--blue);}

  /* toast */
  #toastHost{
    position:fixed;bottom:18px;right:18px;display:flex;flex-direction:column;gap:8px;z-index:999;
  }
  .toast{
    background:var(--ink);color:var(--page);padding:10px 16px;border-radius:9px;font-size:12.5px;
    box-shadow:0 8px 24px rgba(0,0,0,.25);display:flex;align-items:center;gap:8px;
    animation:toastIn .25s ease both;
  }
  html[data-theme="dark"] .toast{background:#e6ebf5;color:#0b0e16;}
  @keyframes toastIn{
    from{opacity:0;transform:translateY(10px);}
    to{opacity:1;transform:translateY(0);}
  }
  .toast.leaving{animation:toastOut .25s ease forwards;}
  @keyframes toastOut{
    to{opacity:0;transform:translateY(10px);}
  }

  /* mobile touch targets */
  @media (max-width:600px){
    h1{font-size:28px;}
    .panel{padding:18px;}
    .mode-btn{padding:14px 0;font-size:14px;}
    .btn-primary, .btn-zip{padding:14px 22px;font-size:14px;width:100%;justify-content:center;}
    .actions{flex-direction:column;align-items:stretch;}
    .btn-clear{text-align:center;}
    header{gap:10px;}
  }