* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    background-color: black;
}

body {
    background-color: black;
    color: white;
    font-family: Arial, sans-serif;
    min-height: 100vh;
    padding-bottom: 60px; /* 为footer留出空间 */
}

.main {
    position: relative;
    width: 100%;
    min-height: calc(100vh - 60px);
}

.main > div {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    padding: 20px;
    background-color: black;
    z-index: -9;
}

.main > div.active {
    z-index: 1;
}

footer.page {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 60px;
    background-color: black;
    display: flex;
    justify-content: space-around;
    align-items: center;
    border-top: 1px solid #333;
    z-index: 10;
}

div.middle {
    position: fixed;
    bottom: 80px;
    left: 0;
    width: 100%;
    height: 280px;
    background-color: black;
    display: flex;
    justify-content: space-around;
    align-items: center;
    border-top: 1px solid #333;
    z-index: 10;
}
textarea.myinfo{
    width: 100%;
    height:100%;
    text-align: left;
}

footer.page button {
    width: 15%;
    height: 40px;
    background-color: black;
    color: white;
    border: 1px solid #333;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
}

footer.page button.active{
    background-color: red;
    color: white;
    border-color: red;
}