:root {
    --left-margin: 200px;
    --right-margin: 200px;
  }

  html,
  body {
    height: 100%;
    margin: 0;
    font-family: Segoe UI, system-ui, sans-serif;
    background: #050606;
    color: #ddd;
  }

  #setupScreen {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 999;
  }

  .setupCard {
    width: 360px;
    background: linear-gradient(180deg, #071012, #001219);
    border: 2px solid rgba(0, 200, 200, 0.22);
    padding: 20px 18px;
    border-radius: 10px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.7);
  }

  .setupCard h2 {
    margin: 0 0 12px 0;
    color: #0ff;
    text-shadow: 0 0 8px rgba(0, 255, 255, 0.08);
  }

  .field {
    margin: 8px 0;
    display: flex;
    flex-direction: column;
    gap: 6px;
  }

  .field input[type="number"],
  .field input[type="text"] {
    padding: 8px;
    border-radius: 6px;
    background: #051a1a;
    border: 1px solid rgba(0, 200, 200, 0.12);
    color: #0ff;
    text-align: center;
  }

  .row {
    display: flex;
    gap: 10px;
  }

  .row>* {
    flex: 1;
  }

  button.primary {
    width: 100%;
    margin-top: 12px;
    padding: 10px;
    border-radius: 8px;
    background: #00d1d1;
    border: none;
    font-weight: 700;
    cursor: pointer;
  }

  /* BombApp layout */
  #bombAppContainer {
    position: relative;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    display: none;
  }

  .side-background {
    position: absolute;
    top: 0;
    bottom: 0;
    background-size: 100% 100%;
    background-repeat: no-repeat;
    background-position: center;
    z-index: 0;
  }

  .left-bg {
    left: 0;
    width: var(--left-margin);
    background-image: url('images/LeftMargin.png');
  }

  .right-bg {
    right: 0;
    width: var(--right-margin);
    background-image: url('images/RightMargin.png');
  }

  #gridContainer {
    position: absolute;
    top: 0;
    bottom: 0;
    left: var(--left-margin);
    right: var(--right-margin);
    display: grid;
    z-index: 2;
    gap: 2px;
    padding: 8px;
    box-sizing: border-box;
    align-content: stretch;
    justify-content: stretch;
  }

  .zone {
    background: #081214;
    border: 1px solid rgba(0, 120, 120, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #9ff;
    font-weight: 700;
    user-select: none;
    overflow: hidden;
    box-sizing: border-box;
  }

  .zone.timer {
    background-size: 100% 100%;
    background-position: center;
    background-repeat: no-repeat;
    color: #ff6666;
  }

  .timer-text {
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: "Lucida Console", "Courier New", monospace;
    letter-spacing: 6px;
    /* BIG spacing = segmented feel */
    transform: scaleY(1.2);
    /* stretch vertically */
    padding-left: 25px;
    padding-top: 15px;
    font-weight: bold;
    color: red;
    text-shadow:
      0 0 4px #ff0000,
      0 0 8px #990000,
      0 0 16px #660000;
    filter: contrast(1.2) brightness(1.2);
    line-height: 1;
    user-select: none;
    width: 100%;
    height: 100%;
    min-height: 1em;
    font-size: clamp(24px, 10vmin, 160px);
    transform: translateZ(0);
    -webkit-font-smoothing: antialiased;
  }

  /* debug small label */
  .label-small {
    position: absolute;
    top: 6px;
    left: 6px;
    font-size: 11px;
    color: rgba(255, 255, 255, 0.5);
  }


  .rect {
    position: absolute;
    border: 2px solid #000;
    box-sizing: border-box;
  }

  #preStartScreen.startScreen {
    position: fixed;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    background: #000;
    z-index: 1000;
  }

  .startButton {
    min-width: 260px;
    min-height: 120px;
    padding: 24px 48px;
    border-radius: 18px;
    border: 2px solid rgba(255, 255, 255, 0.15);
    background: #111;
    color: #fff;
    font-size: 48px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 2px;
    cursor: pointer;
    box-shadow: 0 0 30px rgba(255, 255, 255, 0.08);
  }

  .startButton:hover {
    background: #181818;
  }

  .explosionOverlay {
    position: fixed;
    inset: 0;
    background: red;
    z-index: 9999;
  }


  .explosionMessage {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6vw;
    text-align: center;
    color: #fff;
    font-family: "Segoe UI", system-ui, sans-serif;
    font-size: clamp(32px, 6vw, 88px);
    font-weight: 900;
    letter-spacing: 1px;
    text-transform: uppercase;
    text-shadow: 0 0 12px rgba(0, 0, 0, 0.55);
    z-index: 10000;
    pointer-events: none;
  }