#simple-popup-overlay {
                position: fixed;
                top: 0;
                left: 0;
                width: 100%;
                height: 100%;
                background-color: rgba(0,0,0,0.7);
                z-index: 9998;
            }
            
            #simple-popup {
                position: fixed;
                z-index: 9999;
                background: #fff;
                padding: 20px;
                box-shadow: 0 0 20px rgba(0,0,0,0.3);
                max-width: 90%;
                max-height: 90%;
                overflow-y: auto;
            }
            
            .popup-type-center {
                top: 50%;
                left: 50%;
                transform: translate(-50%, -50%);
                width: 600px;
            }
            
            .popup-type-top {
                top: 0;
                left: 0;
                right: 0;
                width: 100%;
            }
            
            .popup-type-bottom {
                bottom: 0;
                left: 0;
                right: 0;
                width: 100%;
            }
            
            .popup-type-left {
                top: 50%;
                left: 0;
                transform: translateY(-50%);
                width: 300px;
            }
            
            .popup-type-right {
                top: 50%;
                right: 0;
                transform: translateY(-50%);
                width: 300px;
            }
            
            .popup-footer {
                margin-top: 15px;
                padding-top: 15px;
                border-top: 1px solid #eee;
                display: flex;
                justify-content: space-between;
                align-items: center;
            }
            
            .popup-close-btn {
                background: none;
                border: none;
                font-size: 24px;
                cursor: pointer;
                line-height: 1;
                padding: 0 5px;
            }