:root {
      --rs-primary: #5b5bd6;
      --rs-primary-rgb: 91, 91, 214;
      --rs-green: #0d9f6e;
      --rs-orange: #e67e22;
      --rs-text: #1a1d21;
      --rs-muted: #6b7280;
      --rs-border: #e8eaed;
      --rs-bg: #f7f8fa;
      --rs-surface: #ffffff;
    }

    * { box-sizing: border-box; }

    body {
      min-height: 100vh;
      margin: 0;
      color: var(--rs-text);
      font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
      background: var(--rs-bg);
      line-height: 1.45;
    }

    .random-app {
      margin: 0 auto;
    }

    /* Header */
    .app-header {
      text-align: center;
      margin-bottom: 24px;
    }

    .app-header h1 {
      margin: 0 0 6px;
      font-size: 1.5rem;
      font-weight: 700;
      letter-spacing: -0.02em;
    }

    .app-header p {
      margin: 0;
      color: var(--rs-muted);
      font-size: 0.9rem;
    }

    /* Card */
    .app-card {
      background: var(--rs-surface);
      border: 1px solid var(--rs-border);
      /*border-radius: 16px;*/
      overflow: hidden;
    }

    /* Display */
    .display {
      position: relative;
      min-height: 160px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 28px 20px 44px;
      background: #fafbfc;
      border-bottom: 1px solid var(--rs-border);
    }

    .display-value {
      width: 100%;
      text-align: center;
      font-size: clamp(2.75rem, 10vw, 5rem);
      font-weight: 700;
      letter-spacing: -0.04em;
      line-height: 1;
      color: var(--rs-primary);
      overflow-wrap: anywhere;
      word-break: break-word;
      white-space: pre-wrap;
      padding: 0 4px;
    }

    .display-value.multi {
      font-size: clamp(1.15rem, 3.5vw, 1.75rem);
      letter-spacing: -0.02em;
      line-height: 1.4;
      font-weight: 600;
      max-height: min(40vh, 280px);
      overflow-y: auto;
    }

    .display-value.chips {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 6px 8px;
      white-space: normal;
      line-height: 1;
    }

    .display-value.chips .chip {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 2.2em;
      padding: 6px 11px;
      border-radius: 8px;
      background: rgba(var(--rs-primary-rgb), 0.08);
      font-size: clamp(1rem, 3vw, 1.35rem);
      font-weight: 600;
      color: var(--rs-primary);
    }

    .display-value.chips.final .chip {
      background: rgba(13, 159, 110, 0.1);
      color: var(--rs-green);
    }

    .display-value.animate {
      animation: pop 0.12s ease-out;
    }

    .display-value.final {
      animation: final-pop 0.3s ease-out;
      color: var(--rs-green);
    }

    @keyframes pop {
      from { opacity: 0.5; transform: scale(0.96); }
      to   { opacity: 1; transform: scale(1); }
    }

    @keyframes final-pop {
      from { opacity: 0; transform: scale(0.88); }
      to   { opacity: 1; transform: scale(1); }
    }

    .display-status {
      position: absolute;
      bottom: 12px;
      left: 50%;
      transform: translateX(-50%);
      display: flex;
      align-items: center;
      gap: 6px;
      color: var(--rs-muted);
      font-size: 0.75rem;
      font-weight: 500;
    }

    .status-dot {
      width: 6px;
      height: 6px;
      border-radius: 50%;
      background: #c4c9d1;
    }

    .status-dot.running {
      background: var(--rs-primary);
      animation: pulse 1s infinite;
    }

    .status-dot.done {
      background: var(--rs-green);
    }

    @keyframes pulse {
      50% { opacity: 0.4; }
    }

    .display-copy {
      position: absolute;
      top: 10px;
      right: 10px;
      border: 1px solid var(--rs-border);
      border-radius: 6px;
      padding: 4px 10px;
      background: #fff;
      color: var(--rs-muted);
      font-size: 0.7rem;
      font-weight: 600;
      cursor: pointer;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.15s;
    }

    .display-copy.visible {
      opacity: 1;
      pointer-events: auto;
    }

    .display-copy:hover {
      color: var(--rs-primary);
      border-color: #c5c8f0;
    }

    /* Controls */
    .controls {
      padding: 20px;
    }

    .section {
      margin-bottom: 20px;
    }

    .section:last-of-type {
      margin-bottom: 0;
    }

    .section-label {
      margin-bottom: 8px;
      font-size: 0.7rem;
      font-weight: 600;
      letter-spacing: 0.04em;
      text-transform: uppercase;
      color: var(--rs-muted);
    }

    .form-label {
      margin-bottom: 4px;
      font-size: 0.8rem;
      font-weight: 600;
      color: var(--rs-text);
    }

    .form-control,
    .form-select {
      min-height: 40px;
      border-radius: 8px;
      border-color: var(--rs-border);
      font-size: 0.9rem;
      box-shadow: none !important;
    }

    .form-control:focus,
    .form-select:focus {
      border-color: rgba(var(--rs-primary-rgb), 0.5);
    }

    .quick-ranges {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      margin-top: 8px;
    }

    .quick-ranges button {
      border: 1px solid var(--rs-border);
      padding: 4px 10px;
      border-radius: 6px;
      background: #fff;
      color: var(--rs-muted);
      font-size: 0.75rem;
      font-weight: 500;
      cursor: pointer;
      transition: 0.12s;
    }

    .quick-ranges button:hover {
      border-color: #c5c8f0;
      color: var(--rs-primary);
      background: rgba(var(--rs-primary-rgb), 0.04);
    }

    /* Option pills */
    .option-row {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
    }

    .btn-check + .choice {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 36px;
      padding: 4px 12px;
      border: 1px solid var(--rs-border);
      border-radius: 6px;
      background: #fff;
      color: var(--rs-muted);
      font-size: 0.8rem;
      font-weight: 500;
      cursor: pointer;
      transition: 0.12s;
      user-select: none;
    }

    .btn-check + .choice:hover {
      border-color: #c5c8f0;
      color: var(--rs-primary);
    }

    .btn-check:checked + .choice {
      color: #fff;
      border-color: var(--rs-primary);
      background: var(--rs-primary);
    }

    .field-group {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    @media (min-width: 576px) {
      .field-group.cols-3 {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 12px;
      }

      .field-group.cols-2 {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
      }
    }

    .delay-wrap {
      position: relative;
    }

    .delay-wrap .form-control {
      padding-right: 48px;
    }

    .delay-unit {
      position: absolute;
      top: 50%;
      right: 12px;
      transform: translateY(-50%);
      color: var(--rs-muted);
      font-size: 0.8rem;
      pointer-events: none;
    }

    /* Actions */
    .action-area {
      margin-top: 20px;
      padding-top: 16px;
      border-top: 1px solid var(--rs-border);
    }

    .action-btns {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }

    .action-btn {
      min-height: 44px;
      border: 0;
      border-radius: 8px;
      font-size: 0.9rem;
      font-weight: 600;
      cursor: pointer;
      transition: opacity 0.12s, background 0.12s;
    }

    .action-btn:disabled {
      opacity: 0.5;
      cursor: not-allowed;
    }

    #btnPlay {
      background: var(--rs-green);
      color: #fff;
    }

    #btnPlay.is-playing {
      background: var(--rs-orange);
    }

    #btnGo {
      background: var(--rs-primary);
      color: #fff;
    }

    .action-note {
      margin-top: 10px;
      text-align: center;
      color: var(--rs-muted);
      font-size: 0.72rem;
    }

    .error-box {
      margin-top: 12px;
      padding: 10px 12px;
      border-radius: 8px;
      color: #b42318;
      background: #fef3f2;
      border: 1px solid #fecdca;
      font-size: 0.8rem;
    }

    @media (max-width: 575.98px) {
      .random-app {
        /*padding: 20px 12px 36px;*/
      }

      .controls {
        padding: 16px;
      }

      .display {
        min-height: 140px;
        padding: 24px 14px 40px;
      }

      .action-btns {
        grid-template-columns: 1fr;
      }
    }