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

    body {
      background: #1f1f1f;
      color: #ffffff;
      font-family: Arial, Helvetica, sans-serif;
      line-height: 1.5;
      min-height: 100vh;
    }

    .barra-nav {
      background: #2a2a2a;
      border-bottom: 1px solid #4a4a4a;
      padding: 12px 0;
    }

    .menu {
      width: min(900px, 92%);
      margin: 0 auto;
      display: flex;
      gap: 16px;
      list-style: none;
      justify-content: center;
    }

    .menu a {
      color: #ffffff;
      text-decoration: none;
      font-size: 0.95rem;
    }

    .contenedor {
      width: min(900px, 92%);
      margin: 24px auto;
    }

    .titulo {
      text-align: center;
      color: #ffffff;
      margin-bottom: 6px;
      font-size: 1.8rem;
    }

    .subtitulo {
      text-align: center;
      color: #d1d1d1;
      margin-bottom: 18px;
    }

    .zona-boton {
      text-align: center;
      margin-bottom: 16px;
    }

    .boton-basico {
      background: #f2f2f2;
      color: #222222;
      border: 1px solid #9a9a9a;
      border-radius: 8px;
      padding: 8px 14px;
      cursor: pointer;
      font-size: 0.95rem;
    }

    .rejilla {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 12px;
      margin-bottom: 12px;
    }

    .tarjeta {
      background: #303030;
      border: 1px solid #5a5a5a;
      border-radius: 10px;
      padding: 14px;
    }

    h2 {
      color: #f3f3f3;
      margin-bottom: 8px;
      font-size: 1.1rem;
    }

    .label {
      color: #cfcfcf;
      font-size: 0.95rem;
      margin-bottom: 6px;
    }

    .value {
      font-size: 1.4rem;
      font-weight: bold;
      margin-bottom: 4px;
    }

    .imagen-circular {
      width: 90px;
      height: 90px;
      border-radius: 50%;
      object-fit: cover;
      display: block;
      margin: 10px auto 0;
      border: 2px solid #7a7a7a;
    }

    .up {
      color: green;
      font-weight: bold;
    }

    .down {
      color: red;
      font-weight: bold;
    }

    .historial {
      width: 100%;
      border-collapse: collapse;
      font-size: 0.95rem;
    }

    .historial th,
    .historial td {
      border-bottom: 1px solid #575757;
      padding: 8px;
      text-align: left;
    }

    .historial th {
      color: #d6d6d6;
      font-weight: 600;
    }

    .pie {
      margin-top: 14px;
      text-align: center;
      color: #cfcfcf;
      font-size: 0.9rem;
    }

    @media (max-width: 700px) {
      .rejilla {
        grid-template-columns: 1fr;
      }

      .menu {
        flex-wrap: wrap;
      }

      .titulo {
        font-size: 1.5rem;
      }
    }