/* 默认：PC 端隐藏 */
.float-activity {
    display: none; 
}

/* 移动端（屏幕宽度 ≤ 768px）时显示并应用样式 display: block; */
@media screen and (max-width: 1024px) {
    .float-activity {
        display: none; 
        position: fixed;
        right: 15px;
        bottom: 120px;
        background: #fff;
        box-shadow: 0 2px 10px rgba(0,0,0,0.15);
        z-index: 99999;
        overflow: hidden;
        cursor: pointer;
    }

        .float-activity img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .float-activity .close-btn {
            position: absolute;
            top: 5px;
            right: 3px;
            color: #fff;
            font-size: 16px;
            width: 22px;
            height: 22px;
            line-height: 22px;
            text-align: center;
            cursor: pointer;
        }
}