.menu-btn {
      width: 140px;
      height: 140px;
      border-radius: 50%;
      color: white;
      font-size: 16px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      margin: 20px auto;
      border: none;
      box-shadow: 0 4px 10px rgba(0,0,0,0.2);
      transition: transform 0.2s;
    }
.menu-btn:hover { transform: scale(1.05); }
.btn-videos {
  background: linear-gradient(to right, #3a7bd5, #00d2ff);
}

.btn-descargas {
  background: linear-gradient(to right, #f7971e, #ffd200);
}