.cart-btn {
    display: inline-block;
    cursor: pointer;
}

.cart-btn.shake {
    animation: cartShake 0.5s ease-in-out;
    background: black;
}

@keyframes cartShake {
    0% {transform: rotate(0deg);}
    25% {transform: rotate(-30deg);}
    50% {transform: rotate(0deg);}
    75% {transform: rotate(30deg);}
    100% {transform: rotate(0deg);}
}
    div.container {
      background: white;
    }
    .banner {
      min-height: 400px;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: white;
      padding: 40px 20px;

      background:
        linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)),
        url("banner.jpg") center/cover no-repeat;
    }

    .banner-content h1 {
      font-size: 48px;
      margin-bottom: 15px;
    }

    .banner-content p {
      font-size: 20px;
      margin-bottom: 25px;
    }

    .banner-btn {
      display: inline-block;
      padding: 12px 28px;
      background: #ff6b35;
      color: white;
      text-decoration: none;
      border-radius: 6px;
      font-weight: bold;
      transition: 0.3s;
    }

    .banner-btn:hover {
      background: #e85a28;
    }

    @media (max-width: 600px) {
      .banner-content h1 {
        font-size: 32px;
      }

      .banner-content p {
        font-size: 16px;
      }
    }