:root {
      --bg-color: #0f1117;
      --card-bg: #1e293b;
      --text-main: #e2e8f0;
      --text-sub: #94a3b8;
      --border-color: #64748b;
      --btn-bg: #334155;
      --btn-hover: #475569;
      --accent: #3b82f6;
      --accent-border: #60a5fa;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      background-color: var(--bg-color);
      color: var(--text-main);
      font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 100vh;
      padding: 1rem;
    }

    @keyframes slideUpFade {
      0% { opacity: 0; transform: translateY(20px); }
      100% { opacity: 1; transform: translateY(0); }
    }

    .brutal-box {
      background-color: var(--card-bg);
      border: 3px solid var(--border-color);
      border-radius: 12px;
      box-shadow: 8px 8px 0px var(--border-color);
      padding: 2.5rem 2rem;
      max-width: 600px;
      width: 100%;
      text-align: center;
      animation: slideUpFade 0.4s ease-out;
    }

    h1 {
      font-size: 1.8rem;
      margin-bottom: 1rem;
      line-height: 1.4;
    }

    p {
      color: var(--text-sub);
      font-size: 1.1rem;
      line-height: 1.6;
      margin-bottom: 2rem;
    }

    .brutal-btn {
      display: block;
      background-color: var(--btn-bg);
      color: var(--text-main);
      border: 3px solid var(--border-color);
      border-radius: 8px;
      padding: 1.2rem 1.5rem;
      font-size: 1.1rem;
      font-weight: bold;
      cursor: pointer;
      box-shadow: 4px 4px 0px var(--border-color);
      transition: all 0.1s ease;
      width: 100%;
      margin-bottom: 1rem;
      text-align: left;
    }

    .brutal-btn:hover {
      background-color: var(--btn-hover);
      transform: translate(2px, 2px);
      box-shadow: 2px 2px 0px var(--border-color);
    }

    .brutal-btn:active {
      transform: translate(4px, 4px);
      box-shadow: 0px 0px 0px var(--border-color);
    }

    .primary-btn {
      background-color: var(--accent);
      border-color: var(--accent-border);
      box-shadow: 4px 4px 0px var(--accent-border);
      text-align: center;
      font-size: 1.3rem;
    }

    .primary-btn:hover {
      background-color: #2563eb;
      box-shadow: 2px 2px 0px var(--accent-border);
    }

    .primary-btn:active {
      box-shadow: 0px 0px 0px var(--accent-border);
    }

    .hidden {
      display: none !important;
    }

    #progress {
      display: inline-block;
      background-color: var(--btn-bg);
      padding: 0.3rem 0.8rem;
      border-radius: 999px;
      font-size: 0.9rem;
      font-weight: bold;
      color: var(--text-sub);
      margin-bottom: 1.5rem;
      border: 2px solid var(--border-color);
    }

    #question-text {
      font-size: 1.4rem;
      margin-bottom: 2rem;
      line-height: 1.5;
    }

    /* Share Button */
    #share-btn {
      background-color: #000000;
      color: #ffffff;
      border: 3px solid #ffffff;
      box-shadow: 4px 4px 0px #ffffff;
      text-align: center;
      font-size: 1.2rem;
      margin-top: 1rem;
    }
    #share-btn:hover {
      background-color: #111111;
      box-shadow: 2px 2px 0px #ffffff;
    }
    
    #restart-btn {
      text-align: center;
      margin-top: 0.5rem;
      background-color: transparent;
    }