html, body {
      width: 100%;
      height: 100%;
    }
    body {
      margin: 0;
      overflow: hidden;
      background: #87ceeb;
      font-family: Arial, sans-serif;
      touch-action: none;
      overscroll-behavior: none;
      -webkit-user-select: none;
      user-select: none;
    }
    canvas {
      display: block;
      margin: auto;
      width: 100vw;
      height: 100dvh;
      background: linear-gradient(#70c5ce, #ffffff);
    }
    .hud-panel {
      position: fixed;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      z-index: 10;
      width: min(92vw, 380px);
      background: transparent;
      border: 0;
      border-radius: 0;
      padding: 0;
      box-shadow: none;
      touch-action: auto;
      pointer-events: auto;
    }
    .hud-row {
      display: flex;
      gap: 8px;
      align-items: center;
      margin-bottom: 8px;
      background: rgba(255, 255, 255, 0.9);
      border: 1px solid rgba(15, 23, 42, 0.18);
      border-radius: 14px;
      padding: 8px 10px;
      box-shadow: 0 6px 16px rgba(15, 23, 42, 0.10);
      backdrop-filter: blur(4px);
    }
    .hud-row label {
      font-size: 13px;
      font-weight: 700;
      color: #111827;
      white-space: nowrap;
    }
    .hud-row input {
      flex: 1;
      font-size: 14px;
      padding: 7px 9px;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      outline: none;
      min-width: 0;
    }
    .hud-row input:focus {
      border-color: #0284c7;
      box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.2);
    }
    .hud-row select {
      flex: 1;
      font-size: 14px;
      padding: 7px 9px;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      outline: none;
      min-width: 0;
      background: #ffffff;
    }
    .hud-row select:focus {
      border-color: #0284c7;
      box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.2);
    }
    .image-upload-row input[type="file"] {
      flex: 1;
      min-width: 0;
      font-size: 12px;
      color: #0f172a;
    }
    .image-upload-row input[type="file"]::file-selector-button {
      border: 0;
      border-radius: 8px;
      background: #0f172a;
      color: #ffffff;
      font-size: 12px;
      font-weight: 800;
      padding: 7px 9px;
      margin-right: 8px;
      cursor: pointer;
    }
    .image-upload-name {
      display: none;
      margin: -2px 0 8px;
      text-align: center;
      color: #0f172a;
      background: rgba(255, 255, 255, 0.72);
      border-radius: 10px;
      padding: 5px 8px;
      font-size: 11px;
      font-weight: 700;
      line-height: 1.25;
      box-shadow: 0 4px 12px rgba(15, 23, 42, 0.08);
    }
    @media (max-width: 520px) {
      .hud-panel {
        width: min(90vw, 340px);
      }
      .player-choice-button,
      .start-button {
        min-height: 48px;
        font-size: 15px;
      }
      .hud-row {
        min-height: 42px;
      }
      .image-upload-row input[type="file"] {
        font-size: 11px;
      }
    }
    .sprite-hint {
      display: none !important;
    }
    .score-list-title,
    .score-list {
      display: none !important;
    }
    .hud-actions {
      margin-top: 10px;
    }
    .start-button {
      width: 100%;
      border: 0;
      border-radius: 14px;
      background: #0284c7;
      color: #ffffff;
      font-size: 16px;
      font-weight: 900;
      padding: 13px 14px;
      cursor: pointer;
      box-shadow: 0 8px 18px rgba(2, 132, 199, 0.22);
    }
    .start-button:disabled {
      cursor: not-allowed;
      opacity: 0.65;
      box-shadow: none;
    }
    .start-button:active {
      transform: translateY(1px);
    }
    .secondary-button {
      width: 100%;
      border: 1px solid #94a3b8;
      border-radius: 10px;
      background: #ffffff;
      color: #0f172a;
      font-size: 13px;
      font-weight: 700;
      padding: 9px 12px;
      cursor: pointer;
      margin-top: 6px;
    }
    .secondary-button:active {
      transform: translateY(1px);
    }
    .game-title {
      margin-bottom: 12px;
      text-align: center;
      color: #0f172a;
      background: rgba(255, 255, 255, 0.9);
      border: 1px solid rgba(15, 23, 42, 0.18);
      border-radius: 18px;
      padding: 12px 14px;
      box-shadow: 0 8px 18px rgba(15, 23, 42, 0.12);
      backdrop-filter: blur(4px);
    }
    .game-title-main {
      font-size: clamp(30px, 9vw, 46px);
      font-weight: 950;
      line-height: 1;
      letter-spacing: -0.04em;
    }
    .game-title-sub {
      margin-top: 6px;
      font-size: 12px;
      font-weight: 900;
      color: #334155;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }
    .selected-sprite-preview {
      margin-bottom: 10px;
      min-height: 96px;
      background: rgba(255, 255, 255, 0.76);
      border: 1px solid rgba(15, 23, 42, 0.18);
      border-radius: 14px;
      box-shadow: 0 6px 16px rgba(15, 23, 42, 0.10);
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
      padding: 8px;
    }
    .selected-sprite-preview img {
      max-width: 100%;
      max-height: 82px;
      object-fit: contain;
      image-rendering: auto;
    }
    .selected-sprite-label {
      margin: -2px 0 10px;
      text-align: center;
      color: #334155;
      font-size: 11px;
      font-weight: 800;
    }
    .sprite-tools-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
      margin-bottom: 10px;
    }
    .sprite-tool-button {
      border: 1px solid #94a3b8;
      border-radius: 10px;
      background: rgba(255, 255, 255, 0.92);
      color: #0f172a;
      font-size: 12px;
      font-weight: 800;
      padding: 8px 10px;
      cursor: pointer;
    }
    .sprite-tool-button:active {
      transform: translateY(1px);
    }
    .start-status {
      margin-top: 7px;
      text-align: center;
      color: #334155;
      font-size: 11px;
      font-weight: 800;
      min-height: 14px;
    }
    .player-button-row {
      display: flex;
      gap: 10px;
      margin-bottom: 10px;
    }
    .player-choice-button {
      flex: 1;
      border: 1px solid rgba(15, 23, 42, 0.24);
      border-radius: 14px;
      background: rgba(255, 255, 255, 0.9);
      color: #0f172a;
      font-size: 16px;
      font-weight: 900;
      padding: 13px 10px;
      cursor: pointer;
      box-shadow: 0 6px 16px rgba(15, 23, 42, 0.12);
      backdrop-filter: blur(4px);
    }
    .player-choice-button.selected {
      border-color: #0284c7;
      background: #0284c7;
      color: #ffffff;
      box-shadow: 0 8px 18px rgba(2, 132, 199, 0.22);
    }
    .player-choice-button:active {
      transform: translateY(1px);
    }
    .auth-status {
      font-size: 12px;
      font-weight: 700;
      color: #0f172a;
      margin-bottom: 8px;
      line-height: 1.25;
    }
    .auth-note {
      color: #475569;
      font-size: 11px;
      line-height: 1.25;
      margin-bottom: 8px;
    }

    .warning-note {
      display: none;
      color: #92400e;
      background: #fef3c7;
      border: 1px solid #f59e0b;
      border-radius: 8px;
      padding: 7px 9px;
      font-size: 11px;
      line-height: 1.25;
      margin-bottom: 8px;
    }
    .asset-warning {
      display: none !important;
    }
    .pause-side-row {
      justify-content: center;
    }
    .pause-side-row label {
      flex: 1;
      white-space: normal;
      text-align: left;
    }
    .pause-side-row input[type="checkbox"] {
      flex: 0 0 auto;
      width: 20px;
      height: 20px;
      min-width: 20px;
      accent-color: #0284c7;
    }
    .pause-button {
      position: fixed;
      left: calc(12px + env(safe-area-inset-left));
      right: auto;
      bottom: calc(12px + env(safe-area-inset-bottom));
      z-index: 12;
      display: none;
      border: 1px solid rgba(15, 23, 42, 0.24);
      border-radius: 10px;
      background: rgba(255, 255, 255, 0.92);
      color: #0f172a;
      font-size: 13px;
      font-weight: 800;
      padding: 9px 12px;
      cursor: pointer;
      pointer-events: auto;
    }
    .pause-button.pause-right {
      left: auto;
      right: calc(12px + env(safe-area-inset-right));
    }
    .game-over-actions {
      position: fixed;
      z-index: 15;
      display: none;
      gap: 10px;
      pointer-events: auto;
    }
    .game-over-actions button {
      flex: 1;
      border: 0;
      border-radius: 10px;
      font-size: 14px;
      font-weight: 700;
      padding: 10px 12px;
      cursor: pointer;
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.22);
    }
    .game-over-actions .play-again-button {
      background: #0284c7;
      color: #ffffff;
    }
    .game-over-actions .logout-gameover-button {
      background: #ffffff;
      color: #0f172a;
      border: 1px solid #94a3b8;
    }

    .no-background-row {
      justify-content: center;
    }
    .no-background-row label {
      flex: 1;
      white-space: normal;
      text-align: left;
      font-size: 13px;
      font-weight: 900;
    }
    .no-background-row input[type="checkbox"] {
      flex: 0 0 auto;
      width: 20px;
      height: 20px;
      min-width: 20px;
      accent-color: #0284c7;
    }
    .today-scores-modal {
      position: fixed;
      inset: 0;
      z-index: 32;
      display: none;
      align-items: center;
      justify-content: center;
      padding: 16px;
      background: rgba(15, 23, 42, 0.66);
      touch-action: auto;
      pointer-events: auto;
    }
    .today-scores-card {
      width: min(94vw, 560px);
      max-height: min(82dvh, 720px);
      overflow: auto;
      background: rgba(255, 255, 255, 0.97);
      color: #0f172a;
      border: 1px solid rgba(15, 23, 42, 0.16);
      border-radius: 18px;
      padding: 16px;
      box-shadow: 0 20px 48px rgba(15, 23, 42, 0.34);
      backdrop-filter: blur(5px);
    }
    .today-scores-title {
      font-size: 24px;
      font-weight: 950;
      text-align: center;
      margin-bottom: 6px;
    }
    .today-scores-subtitle {
      font-size: 12px;
      font-weight: 800;
      text-align: center;
      color: #475569;
      margin-bottom: 12px;
      line-height: 1.35;
    }
    .today-scores-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
      margin-bottom: 12px;
    }
    .today-score-summary-card {
      border: 1px solid rgba(15, 23, 42, 0.14);
      border-radius: 14px;
      background: #f8fafc;
      padding: 10px;
    }
    .today-score-summary-name {
      font-size: 16px;
      font-weight: 950;
      margin-bottom: 6px;
    }
    .today-score-summary-line {
      font-size: 12px;
      font-weight: 800;
      color: #334155;
      line-height: 1.45;
    }
    .today-scores-table-wrap {
      overflow-x: auto;
      border: 1px solid rgba(15, 23, 42, 0.12);
      border-radius: 12px;
      background: #ffffff;
    }
    .today-scores-table {
      width: 100%;
      border-collapse: collapse;
      font-size: 12px;
      font-weight: 800;
    }
    .today-scores-table th,
    .today-scores-table td {
      padding: 8px 7px;
      border-bottom: 1px solid rgba(15, 23, 42, 0.08);
      text-align: left;
      white-space: nowrap;
    }
    .today-scores-table th {
      background: #0f172a;
      color: #ffffff;
      font-size: 11px;
      text-transform: uppercase;
      letter-spacing: 0.04em;
    }
    .today-scores-actions {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
      margin-top: 12px;
    }
    .today-scores-actions button {
      border: 0;
      border-radius: 12px;
      font-size: 14px;
      font-weight: 950;
      padding: 11px 12px;
      cursor: pointer;
    }
    .today-scores-refresh-button {
      background: #0284c7;
      color: #ffffff;
    }
    .today-scores-close-button {
      background: #ffffff;
      color: #0f172a;
      border: 1px solid #94a3b8 !important;
    }
    @media (max-width: 520px) {
      .today-scores-grid {
        grid-template-columns: 1fr;
      }
      .today-scores-card {
        max-height: 84dvh;
        padding: 14px;
      }
    }

    .hundred-photo-modal {
      position: fixed;
      inset: 0;
      z-index: 30;
      display: none;
      align-items: center;
      justify-content: center;
      padding: 18px;
      background: rgba(15, 23, 42, 0.62);
      touch-action: auto;
      pointer-events: auto;
    }
    .hundred-photo-card {
      width: min(92vw, 420px);
      background: rgba(255, 255, 255, 0.96);
      color: #0f172a;
      border: 1px solid rgba(15, 23, 42, 0.16);
      border-radius: 18px;
      padding: 18px;
      box-shadow: 0 20px 48px rgba(15, 23, 42, 0.34);
      text-align: center;
      backdrop-filter: blur(5px);
    }
    .hundred-photo-title {
      font-size: 22px;
      font-weight: 950;
      margin-bottom: 8px;
    }
    .hundred-photo-text {
      font-size: 13px;
      font-weight: 700;
      line-height: 1.4;
      color: #334155;
      margin-bottom: 14px;
    }
    .hundred-photo-button {
      width: 100%;
      border: 0;
      border-radius: 14px;
      background: #dc2626;
      color: #ffffff;
      font-size: 16px;
      font-weight: 950;
      padding: 13px 14px;
      cursor: pointer;
      box-shadow: 0 8px 18px rgba(220, 38, 38, 0.24);
    }
    .hundred-photo-button:active {
      transform: translateY(1px);
    }
    .hundred-photo-secondary-button {
      width: 100%;
      border: 1px solid #94a3b8;
      border-radius: 14px;
      background: #ffffff;
      color: #0f172a;
      font-size: 14px;
      font-weight: 900;
      padding: 12px 14px;
      cursor: pointer;
      margin-top: 8px;
      box-shadow: 0 6px 14px rgba(15, 23, 42, 0.12);
    }
    .hundred-photo-secondary-button:active {
      transform: translateY(1px);
    }
    .hundred-photo-start-button {
      display: none;
      width: 100%;
      border: 0;
      border-radius: 14px;
      background: #0284c7;
      color: #ffffff;
      font-size: 16px;
      font-weight: 950;
      padding: 13px 14px;
      cursor: pointer;
      margin-top: 8px;
      box-shadow: 0 8px 18px rgba(2, 132, 199, 0.24);
    }
    .hundred-photo-start-button:active {
      transform: translateY(1px);
    }

    .settings-panel {
      margin-bottom: 10px;
      background: rgba(255, 255, 255, 0.9);
      border: 1px solid rgba(15, 23, 42, 0.18);
      border-radius: 14px;
      box-shadow: 0 6px 16px rgba(15, 23, 42, 0.10);
      backdrop-filter: blur(4px);
      overflow: hidden;
    }
    .settings-panel summary {
      list-style: none;
      cursor: pointer;
      padding: 12px 14px;
      color: #0f172a;
      font-size: 14px;
      font-weight: 950;
      text-align: center;
      user-select: none;
    }
    .settings-panel summary::-webkit-details-marker {
      display: none;
    }
    .settings-panel summary::after {
      content: " ▾";
      font-weight: 900;
    }
    .settings-panel[open] summary::after {
      content: " ▴";
    }
    .settings-content {
      padding: 0 10px 10px;
    }
    .settings-content .hud-row {
      box-shadow: none;
      margin-bottom: 8px;
      background: rgba(255, 255, 255, 0.95);
    }
    .settings-content .secondary-button {
      margin-top: 0;
      min-height: 42px;
      font-size: 14px;
      font-weight: 950;
      border-radius: 12px;
    }
    #spriteToolsRow,
    #noBackgroundRow,
    #startGameButton,
    #startStatusMessage {
      display: none !important;
    }

/* ── Developer / Admin settings ─────────────────────────────────────────── */
.dev-login-box,
.dev-controls {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid rgba(15, 23, 42, 0.16);
}
.dev-section-title {
  text-align: center;
  font-size: 13px;
  font-weight: 950;
  color: #0f172a;
  margin-bottom: 7px;
}
.dev-login-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 7px;
  margin-bottom: 7px;
}
.dev-login-grid input,
.dev-param-card input[type="number"] {
  min-width: 0;
  border: 1px solid #cbd5e1;
  border-radius: 10px;
  background: #ffffff;
  color: #0f172a;
  font-size: 14px;
  font-weight: 900;
  padding: 7px 8px;
  outline: none;
}
.dev-login-grid input:focus,
.dev-param-card input:focus {
  border-color: #0284c7;
  box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.18);
}
.dev-unlock-button {
  margin-bottom: 7px;
}
.dev-mode-status {
  min-height: 14px;
  text-align: center;
  font-size: 11px;
  font-weight: 900;
  color: #475569;
  line-height: 1.2;
}
.dev-mode-status.dev-active,
.dev-warning {
  color: #991b1b;
}
.dev-warning {
  background: #fee2e2;
  border: 1px solid #fca5a5;
  border-radius: 10px;
  padding: 6px 8px;
  font-size: 11px;
  font-weight: 950;
  text-align: center;
  margin-bottom: 7px;
}
.dev-param-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 7px;
  align-items: stretch;
}
.dev-param-card {
  display: grid;
  grid-template-rows: auto auto;
  gap: 5px;
  align-items: center;
  justify-items: center;
  min-width: 0;
  background: rgba(255, 255, 255, 0.95);
  border: 1px solid rgba(15, 23, 42, 0.12);
  border-radius: 12px;
  padding: 7px 8px;
}
.dev-param-card label {
  color: #0f172a;
  font-size: 12px;
  font-weight: 950;
  text-align: center;
  line-height: 1.05;
  white-space: nowrap;
}
.dev-param-card input[type="number"] {
  width: min(100%, 92px);
  text-align: center;
}
.dev-gm-card input[type="checkbox"] {
  width: 24px;
  height: 24px;
  accent-color: #dc2626;
}
.dev-button-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 7px;
  margin-top: 7px;
}
.dev-button-row .secondary-button {
  padding-top: 8px;
  padding-bottom: 8px;
}
.dev-help-text {
  margin-top: 6px;
  color: #475569;
  font-size: 10.5px;
  font-weight: 800;
  text-align: center;
  line-height: 1.2;
}
@media (max-width: 330px) {
  .dev-param-card label {
    font-size: 11px;
  }
  .dev-param-card input[type="number"] {
    width: min(100%, 76px);
  }
}