body {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    position: relative;
    top: 0;
    left: 0;
    background-color: #fff;
    min-height: 135vh;
}

.top-image,
.bottom-image,
.desc-tip {
    display: block;
    margin: 0 auto;
    width: 100%;
    max-width: 720px;
}
.bottom {
    min-height: 59vh;
}
.bottom,
.icon-and-buttons {
    width: 100%;
    max-width: 720px;
    display: block;
    margin: 0 auto;
}
.icon-and-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
}

.icon-and-buttons img {
    max-width: 100%;
}

.icon-and-buttons .icon {
    margin: 10px;
    width: 30%;
    height: auto;
}

.tip {
    position: relative;
}
.top-image,
.desc-tip,
.bottom-image {
    height: auto;
}

.fixed-image {
    position: absolute;
    top: -20px;
    right: 5px;
    width: 63px;
    height: 82px;
}
.icon-and-buttons a {
    transition: transform 0.2s;
    display: block;
    width: 100%;
    height: 60px;
    margin: 5px;
}
.hidden {
    visibility: hidden;
}
.wx {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 9999;
    text-align: center;
}
.wx img {
    width: 100%;
    height: auto;
    margin-top: 0;
}
.icon-and-buttons .button:active {
    transform: scale(0.9);
}
img {
    user-select: none;
    pointer-events: none;
}
.btn1{
    padding: 14px 55px; cursor: pointer; width: auto; margin: 8px; border: none;
    border-radius: 30px; font-size: 20px; background: #d02525; color: white;
}
.btn2 {
    padding: 14px 55px; cursor: pointer; width: auto; margin: 8px; border: none;
    border-radius: 30px; font-size: 20px; background: #4285f4; color: white;
}