body {
    margin: 0;
    padding: 0;
    background-color: #f0f7ff;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.page-container {
    width: 100%;
    max-width: 750px;
    line-height: 0;
}

.activity-wrapper {
    position: relative;
    width: 100%;
    line-height: 0;
}

.bg-img {
    width: 100%;
    display: block;
    height: auto;
}

/* 立即领取按钮：位置与动态效果 */
.btn-on-img {
    position: absolute;
    z-index: 10;
    width: 60%;
    left: 50%;
    transform: translateX(-50%);
    bottom: 86.5%;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
    animation: pulseBtn 1.5s infinite ease-in-out;
}

@keyframes pulseBtn {
    0% {
        transform: translateX(-50%) scale(1);
        filter: brightness(1);
    }
    50% {
        transform: translateX(-50%) scale(1.08);
        filter: brightness(1.1);
    }
    100% {
        transform: translateX(-50%) scale(1);
        filter: brightness(1);
    }
}

.btn-on-img img {
    width: 100%;
    display: block;
    filter: drop-shadow(0 0 10px rgba(255, 215, 0, 0.5));
}

.btn-on-img:active {
    transform: translateX(-50%) scale(0.92) !important;
    animation: none;
}

/* 悬浮客服 */
.float-service {
    position: fixed;
    right: 15px;
    bottom: 20%;
    width: 70px;
    z-index: 100;
}

.float-service img {
    width: 100%;
    display: block;
}