:root {
      --bg-0: #02060c;
      --bg-1: #061323;
      --bg-2: #0a1f35;
      --hud: rgba(4, 12, 22, 0.88);
      --panel: rgba(7, 20, 35, 0.92);
      --ink: #d7ebff;
      --muted: #8ea6c0;
      --danger: #ff5d73;
      --ok: #6df5d3;
      --accent: #77beff;
      --warn: #ffd07a;
    }

    * { box-sizing: border-box; }
    body {
      margin: 0;
      min-height: 100vh;
      color: var(--ink);
      background:
        radial-gradient(circle at 20% 10%, rgba(40, 88, 146, 0.25), transparent 35%),
        radial-gradient(circle at 80% 90%, rgba(22, 99, 115, 0.35), transparent 42%),
        linear-gradient(180deg, var(--bg-2) 0%, var(--bg-1) 40%, var(--bg-0) 100%);
      font-family: "Trebuchet MS", Verdana, sans-serif;
      overflow: hidden;
    }

    #app {
      height: 100vh;
      display: grid;
      grid-template-rows: auto 1fr auto;
    }

    .top-hud {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      gap: 10px;
      padding: 10px;
      background: var(--hud);
      border-bottom: 1px solid rgba(141, 186, 230, 0.2);
      align-items: center;
      font-size: 14px;
    }

    .hud-block { display: flex; align-items: center; gap: 10px; }
    .hud-right { justify-content: flex-end; }
    .hud-center { justify-content: center; }
    .badge {
      border: 1px solid rgba(119, 190, 255, 0.35);
      border-radius: 999px;
      padding: 3px 10px;
      color: var(--accent);
      background: rgba(8, 25, 42, 0.9);
    }

    #stage-wrap {
      position: relative;
      overflow: hidden;
    }

    #stage-wrap canvas {
      display: block;
      width: 100%;
      height: 100%;
      position: absolute;
      inset: 0;
      background: transparent;
    }

    #game-canvas {
      z-index: 2;
      pointer-events: auto;
    }

    #stage-wrap canvas:not(#game-canvas) {
      z-index: 1;
      pointer-events: none;
    }

    .bottom-hud {
      display: grid;
      gap: 8px;
      padding: 10px;
      background: var(--hud);
      border-top: 1px solid rgba(141, 186, 230, 0.2);
    }

    .inventory-help {
      margin-bottom: 0;
      color: #bcd9f7;
      font-size: 12px;
      line-height: 1.25;
      letter-spacing: 0.01em;
    }

    #inventory {
      display: grid;
      grid-template-columns: repeat(5, minmax(105px, 1fr));
      gap: 8px;
    }

    .slot {
      border: 1px solid rgba(119, 190, 255, 0.3);
      border-radius: 8px;
      padding: 7px;
      min-height: 62px;
      background: rgba(11, 29, 49, 0.9);
      cursor: pointer;
      user-select: none;
      text-align: left;
      line-height: 1.2;
      font: inherit;
      color: inherit;
    }

    .slot.cooling { opacity: 0.55; border-color: rgba(160, 168, 178, 0.5); }
    .slot.active { border-color: rgba(109, 245, 211, 0.7); box-shadow: inset 0 0 14px rgba(109, 245, 211, 0.15); }
    .slot.ready { border-color: rgba(127, 203, 255, 0.6); }
    .slot.selected {
      outline: 2px solid rgba(255, 208, 122, 0.95);
      background: rgba(37, 57, 76, 0.95);
      box-shadow: 0 0 0 1px rgba(255, 208, 122, 0.4), inset 0 0 16px rgba(255, 226, 160, 0.1);
    }

    .slot-name { font-size: 12px; color: var(--ink); }
    .slot-meta { font-size: 11px; color: var(--muted); margin-top: 4px; }

    #overlay {
      position: absolute;
      inset: 0;
      display: grid;
      place-items: center;
      pointer-events: none;
    }

    .panel {
      width: min(700px, calc(100vw - 40px));
      background: var(--panel);
      border: 1px solid rgba(123, 182, 235, 0.4);
      border-radius: 12px;
      padding: 20px;
      box-shadow: 0 20px 40px rgba(0, 0, 0, 0.45);
      pointer-events: all;
    }

    .panel h1,
    .panel h2 { margin: 0 0 12px; }
    .panel p { margin: 0 0 10px; color: var(--muted); }

    .actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 15px; }

    button {
      border: 1px solid rgba(119, 190, 255, 0.5);
      border-radius: 8px;
      background: linear-gradient(180deg, rgba(40, 79, 120, 0.9), rgba(18, 44, 70, 0.9));
      color: var(--ink);
      padding: 10px 14px;
      cursor: pointer;
    }

    button.secondary {
      border-color: rgba(145, 167, 187, 0.45);
      background: linear-gradient(180deg, rgba(44, 53, 64, 0.85), rgba(22, 30, 39, 0.85));
      color: #c9d4df;
    }

    button:disabled { opacity: 0.5; cursor: not-allowed; }

    .levels {
      margin-top: 10px;
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(90px, 1fr));
      gap: 8px;
      max-height: 300px;
      overflow: auto;
      padding-right: 5px;
    }

    .level-chip {
      border: 1px solid rgba(119, 190, 255, 0.35);
      border-radius: 8px;
      padding: 8px;
      text-align: center;
      background: rgba(9, 27, 45, 0.82);
      cursor: pointer;
    }

    .level-chip.locked { opacity: 0.4; cursor: not-allowed; }
    .warning-banner {
      position: absolute;
      left: 10px;
      right: 10px;
      bottom: 80px;
      background: rgba(90, 20, 27, 0.88);
      border: 1px solid rgba(255, 106, 128, 0.7);
      color: #ffd7de;
      border-radius: 8px;
      font-size: 12px;
      padding: 7px 10px;
      pointer-events: none;
    }

    .storage-warning {
      color: #ffd7a8;
      font-size: 12px;
      margin-left: 8px;
    }

    @media (max-width: 860px) {
      #inventory { grid-template-columns: repeat(2, minmax(120px, 1fr)); }
      .top-hud { grid-template-columns: 1fr; gap: 8px; }
      .hud-right, .hud-center, .hud-block { justify-content: flex-start; }
    }

.portal-back {
  position: fixed;
  bottom: 8.25rem;
  left: 1rem;
  z-index: 100;
  color: #00c8c8;
  font-size: 0.85rem;
  text-decoration: none;
  opacity: 0.7;
  transition: opacity 150ms ease;
}
.portal-back:hover { opacity: 1; }

@media (max-width: 860px) {
  .portal-back { bottom: 12.25rem; }
}