:root {
      /* dark workspace zone */
      --ink: #0F0F11;
      --ink-2: #17171A;
      --ink-line: #26262B;
      --on-ink: #ECECEC;
      --on-ink-dim: #8C8C92;

      /* warm paper control deck */
      --paper: #F6F2E9;
      --paper-card: #FFFDF8;
      --black: #16140F;
      --muted: #6E675A;
      --line: #E2DAC7;
      --field-bg: #FFFFFF;

      /* signature + danger */
      --hi: #FFE100;
      --hi-ink: #1A1500;
      --hot: #FF4D2E;

      --r: 14px;
      --r-sm: 10px;
    }

    * { box-sizing: border-box; }

    html, body { height: 100%; }

    body {
      margin: 0;
      height: 100%;
      overflow: hidden;
      display: flex;
      flex-direction: column;
      background: var(--ink);
      color: var(--on-ink);
      font-family: "Space Grotesk", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
      -webkit-font-smoothing: antialiased;
    }

    /* ---------- top bar ---------- */
    .topbar {
      flex: 0 0 auto;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      padding: 14px 28px;
      background: var(--ink);
      border-bottom: 1px solid var(--ink-line);
      position: sticky;
      top: 0;
      z-index: 30;
    }

    .brand {
      display: flex;
      align-items: center;
      gap: 14px;
      flex-wrap: wrap;
    }

    .brand-mark {
      font-family: 'Anton', Impact, 'Arial Narrow', sans-serif;
      font-size: 30px;
      letter-spacing: .05em;
      line-height: .9;
      color: var(--hi-ink);
      background: var(--hi);
      padding: 3px 11px 5px;
      display: inline-block;
      transform: skewX(-6deg);
      border-radius: 2px;
    }

    .brand-zh {
      font-size: 15px;
      font-weight: 600;
      letter-spacing: .14em;
      color: var(--on-ink);
    }

    .top-actions {
      display: flex;
      align-items: center;
      justify-content: flex-end;
      gap: 10px;
      flex-wrap: wrap;
    }

    .stamp {
      appearance: none;
      border: 0;
      cursor: pointer;
      font-family: 'Anton', Impact, sans-serif;
      font-size: 15px;
      letter-spacing: .06em;
      color: var(--ink);
      background: var(--on-ink);
      padding: 11px 20px;
      border-radius: 8px;
      display: inline-flex;
      align-items: center;
      gap: 9px;
      transition: transform .08s ease, background .15s ease;
    }
    .stamp:hover { background: #fff; }
    .stamp:active { transform: translateY(1px); }
    .stamp-secondary {
      color: var(--on-ink);
      background: transparent;
      border: 1px solid var(--ink-line);
    }
    .stamp-secondary:hover {
      color: #fff;
      background: var(--ink-2);
    }
    .stamp svg {
      width: 15px;
      height: 15px;
      display: block;
      flex: 0 0 auto;
    }

    /* ---------- layout: only the deck may scroll ---------- */
    main {
      flex: 1 1 auto;
      min-height: 0;
      overflow: hidden;
      display: grid;
      grid-template-columns: minmax(340px, 400px) minmax(0, 1fr);
    }

    /* ---------- control deck (paper) ---------- */
    .deck {
      background: var(--paper);
      border-right: 1px solid var(--line);
      padding: 22px 22px 30px;
      overflow: auto;
      min-height: 0;
      scrollbar-gutter: stable;
    }

    .grp {
      padding: 0 0 22px;
      margin: 0 0 22px;
      border-bottom: 1px dashed var(--line);
    }
    .grp:last-child { border-bottom: 0; margin-bottom: 0; padding-bottom: 0; }

    .grp-h {
      display: flex;
      align-items: baseline;
      gap: 10px;
      margin: 0 0 14px;
      font-size: 12.5px;
      font-weight: 700;
      letter-spacing: .12em;
      text-transform: uppercase;
      color: var(--black);
    }
    .grp-h .num {
      font-family: 'Anton', Impact, sans-serif;
      font-size: 18px;
      letter-spacing: .04em;
      color: var(--hot);
      line-height: 1;
    }

    .field { margin: 0 0 12px; }
    .field:last-child { margin-bottom: 0; }

    .fld {
      display: block;
      font-size: 10.5px;
      letter-spacing: .1em;
      text-transform: uppercase;
      font-weight: 700;
      color: var(--muted);
      margin: 0 0 6px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
    }

    .deck input[type="text"],
    .deck input[type="number"],
    .deck select,
    .deck textarea {
      width: 100%;
      background: var(--field-bg);
      border: 1px solid var(--line);
      border-radius: var(--r-sm);
      padding: 9px 11px;
      font: inherit;
      color: var(--black);
      outline: none;
      transition: border-color .15s ease, box-shadow .15s ease;
    }
    .deck input[type="color"] {
      width: 100%;
      height: 40px;
      border: 1px solid var(--line);
      border-radius: var(--r-sm);
      padding: 4px;
      background: var(--field-bg);
      cursor: pointer;
    }
    .deck textarea {
      min-height: 200px;
      resize: vertical;
      line-height: 1.55;
      font-size: 14px;
    }
    .deck input:focus,
    .deck select:focus,
    .deck textarea:focus {
      border-color: var(--black);
      box-shadow: 0 0 0 3px rgba(22, 20, 15, .08);
    }

    /* slider row */
    .slider {
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 10px;
      align-items: center;
    }
    .slider input[type="range"] {
      width: 100%;
      accent-color: var(--hot);
      cursor: pointer;
    }
    .pill {
      min-width: 58px;
      text-align: center;
      font-size: 12px;
      font-weight: 700;
      font-variant-numeric: tabular-nums;
      color: var(--hi);
      background: var(--ink);
      border-radius: 999px;
      padding: 5px 9px;
    }

    /* dropzone */
    .drop {
      display: block;
      border: 1.5px dashed var(--line);
      border-radius: var(--r);
      padding: 22px 16px;
      text-align: center;
      cursor: pointer;
      background: var(--paper-card);
      transition: border-color .15s ease, background .15s ease, transform .08s ease;
    }
    .drop:hover { border-color: var(--hot); background: #fff; }
    .drop:active { transform: translateY(1px); }
    .file-input-automation,
    .agent-image-url,
    .agent-load-image-btn {
      position: absolute;
      width: 1px;
      height: 1px;
      margin: 0;
      padding: 0;
      border: 0;
      opacity: 0.01;
      pointer-events: none;
    }
    .agent-load-image-btn {
      pointer-events: auto;
    }
    .drop-ico {
      display: block;
      font-size: 20px;
      line-height: 1;
      color: var(--hot);
      margin-bottom: 8px;
    }
    .drop strong { display: block; font-weight: 700; color: var(--black); font-size: 14px; }
    .drop small { display: block; margin-top: 4px; color: var(--muted); font-size: 11.5px; }

    .btn {
      appearance: none;
      border: 0;
      border-radius: var(--r-sm);
      padding: 10px 14px;
      font: inherit;
      font-weight: 700;
      font-size: 13px;
      cursor: pointer;
      transition: transform .08s ease, background .15s ease, color .15s ease;
    }
    .btn:active { transform: translateY(1px); }
    .btn.ghost-danger {
      width: 100%;
      margin-top: 10px;
      background: transparent;
      color: var(--hot);
      border: 1px solid var(--line);
    }
    .btn.ghost-danger:hover { background: #fff; border-color: var(--hot); }

    /* advanced (03 + 04) */
    .advanced {
      border: 1px solid var(--line);
      border-radius: var(--r);
      background: var(--paper-card);
      overflow: hidden;
    }
    .advanced > summary {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 12px;
      padding: 14px 16px;
      cursor: pointer;
      list-style: none;
      font-size: 12.5px;
      font-weight: 700;
      letter-spacing: .12em;
      text-transform: uppercase;
      color: var(--black);
    }
    .advanced > summary::-webkit-details-marker { display: none; }
    .advanced > summary .adv-tag {
      font-size: 10.5px;
      letter-spacing: .08em;
      color: var(--muted);
      font-weight: 600;
    }
    .advanced > summary .adv-tag::after { content: "＋ 展开"; }
    .advanced[open] > summary { border-bottom: 1px solid var(--line); }
    .advanced[open] > summary .adv-tag::after { content: "－ 收起"; }
    .adv-body { padding: 18px 16px 6px; }

    /* ---------- stage (dark workspace, never scrolls) ---------- */
    .stage {
      background: var(--ink);
      display: flex;
      flex-direction: column;
      gap: 0;
      padding: 20px;
      min-height: 0;
      overflow: hidden;
    }

    .canvas-wrap {
      flex: 1 1 auto;
      min-height: 0;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
      border-radius: var(--r);
      border: 1px solid var(--ink-line);
      padding: 24px;
      background-color: #0a0a0c;
      background-image:
        linear-gradient(45deg, #15151a 25%, transparent 25%),
        linear-gradient(-45deg, #15151a 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #15151a 75%),
        linear-gradient(-45deg, transparent 75%, #15151a 75%);
      background-size: 22px 22px;
      background-position: 0 0, 0 11px, 11px -11px, -11px 0;
    }

    canvas {
      display: block;
      flex: 0 0 auto;
      border-radius: 4px;
      box-shadow: 0 24px 70px rgba(0, 0, 0, .55);
      background: #fff;
    }

    .modal[hidden] { display: none; }
    .modal {
      position: fixed;
      inset: 0;
      z-index: 80;
      display: grid;
      place-items: center;
      padding: 20px;
      background: rgba(15, 15, 17, .78);
    }
    .modal-panel {
      width: min(760px, 100%);
      max-height: min(760px, calc(100vh - 40px));
      display: grid;
      grid-template-rows: auto minmax(220px, 1fr) auto;
      gap: 16px;
      padding: 20px;
      border: 1px solid var(--ink-line);
      border-radius: var(--r);
      background: var(--paper);
      color: var(--black);
      box-shadow: 0 30px 90px rgba(0, 0, 0, .55);
    }
    .modal-head {
      display: flex;
      align-items: flex-start;
      justify-content: space-between;
      gap: 18px;
    }
    .modal-kicker {
      margin: 0 0 4px;
      font-family: 'Anton', Impact, sans-serif;
      font-size: 13px;
      letter-spacing: .12em;
      color: var(--hot);
    }
    .modal h2 {
      margin: 0;
      font-size: 24px;
      line-height: 1.1;
      letter-spacing: 0;
    }
    .icon-btn {
      appearance: none;
      width: 38px;
      height: 38px;
      border: 1px solid var(--line);
      border-radius: 8px;
      display: inline-grid;
      place-items: center;
      flex: 0 0 auto;
      color: var(--black);
      background: #fff;
      cursor: pointer;
    }
    .icon-btn:hover { border-color: var(--hot); }
    .icon-btn svg {
      width: 18px;
      height: 18px;
    }
    .prompt-box {
      width: 100%;
      min-height: 220px;
      resize: none;
      overflow: auto;
      border: 1px solid var(--line);
      border-radius: var(--r-sm);
      padding: 14px;
      background: #fff;
      color: var(--black);
      font: 13px/1.55 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
      outline: none;
    }
    .prompt-box:focus {
      border-color: var(--black);
      box-shadow: 0 0 0 3px rgba(22, 20, 15, .08);
    }
    .modal-actions {
      display: flex;
      justify-content: flex-end;
    }

    /* ---------- a11y / motion ---------- */
    :focus-visible {
      outline: 2px solid var(--hi);
      outline-offset: 2px;
    }
    @media (prefers-reduced-motion: reduce) {
      * { transition: none !important; }
    }

    /* ---------- responsive ---------- */
    @media (max-width: 900px) {
      .topbar {
        align-items: flex-start;
        padding: 12px 16px;
      }
      .brand-sub { display: none; }
      .top-actions {
        max-width: 100%;
      }
      .stamp {
        padding: 10px 13px;
        font-size: 13px;
      }

      main {
        display: flex;
        flex-direction: column;
      }
      .deck {
        flex: 0 0 auto;
        max-height: 48vh;
        border-right: 0;
        border-bottom: 1px solid var(--line);
      }
      .stage {
        flex: 1 1 auto;
        min-height: 0;
      }
    }

    @media (max-width: 620px) {
      .topbar {
        display: grid;
        grid-template-columns: 1fr;
      }
      .top-actions {
        justify-content: stretch;
      }
      .top-actions .stamp {
        flex: 1 1 0;
        justify-content: center;
      }
      .modal {
        padding: 10px;
      }
      .modal-panel {
        max-height: calc(100vh - 20px);
        padding: 16px;
      }
    }