body {
    background-color: #d0e4fe;
    text-align: center;
    vertical-align: middle;
    height: 700px;
    max-height: 700px;
}

#word {
    height: 350px;
    vertical-align: middle;
}

#pinyin {
    height: 100px;
    font-size: 50px;
    line-height: 100px;
}

.righttop {
    padding: 10px;
    background-color: chartreuse;
    border: 1px;
    border-radius: 5px;
    position: absolute;
    right: 10px;
}

.loginarea {
    display: none;
    background-color: khaki;
    flex-direction: column;
    vertical-align: middle;
    height: 150px;
    width: 100%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    /* margin-top值为自身高度的一半 */
    position: absolute;
    padding: 0;
}

.line {
    margin: 10px;
    height: 30px;
    width: 100%;
    /* display: inline-block; */
    flex-direction: column;
}

.text {
    width: 200px;
}

.level {
    display: flex;
    flex-direction: row;
}

input[type='checkbox'] {
    margin-left: 8px;
}

.button {
    height: 40px;
    width: 40px;
    border-radius: 50%;
    margin-left: 50px;
}

.comment {
    /* position: fixed; */
    /* bottom: 0; */
    left: 5px;
    right: 5px;
    padding: 5px;
    box-sizing: border-box;
}

.comment>div {
    text-align: left;
    min-height: 20px;
    max-height: 100px;
    overflow-y: auto;
    line-height: 20px;
    width: 100%;
    padding: 5px;
    box-sizing: border-box;
    border: 1px solid #999;
    border-radius: 3px;
}