body { background-color: #f4f7fe; }
    .checkout-wrapper { margin-top: 120px; margin-bottom: 100px; }

    .checkout-card {
        background: white;
        border-radius: 25px;
        padding: 30px;
        border: 1px solid #edf2f7;
        margin-bottom: 25px;
    }

    .section-title {
        display: flex;
        align-items: center;
        gap: 10px;
        font-weight: 800;
        margin-bottom: 20px;
        color: #1e293b;
    }

    /* Address Selection */
    .address-box {
        border: 2px solid #f1f5f9;
        border-radius: 20px;
        padding: 20px;
        position: relative;
        transition: 0.3s;
    }
    .address-box.selected {
        border-color: #4361ee;
        background: #f8faff;
    }

    /* Shipping Method */
    .shipping-option {
        border: 1px solid #e2e8f0;
        border-radius: 15px;
        padding: 15px;
        cursor: pointer;
        transition: 0.3s;
    }
    .shipping-option:hover { border-color: #4361ee; background: #f8faff; }

    /* Payment Summary */
    .summary-card {
        background: white;
        border-radius: 25px;
        padding: 30px;
        border: 1px solid #edf2f7;
        position: sticky;
        top: 110px;
    }

    .product-mini {
        display: flex;
        gap: 15px;
        padding: 15px 0;
        border-bottom: 1px solid #f1f5f9;
    }
    .product-mini img { width: 60px; height: 60px; border-radius: 12px; object-fit: cover; }

    .btn-pay {
        background: #4361ee;
        color: white;
        border: none;
        border-radius: 15px;
        padding: 16px;
        font-weight: 700;
        width: 100%;
        box-shadow: 0 10px 20px rgba(67, 97, 238, 0.2);
    }