* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
.nav-bar {
    width: 100%;
    height: 44px;
    background-color: #f0f0f0;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
}
.back {
    width: 44px;
    height: 44px;
    position: absolute;
    left: 10px;
    display: flex;
    align-items: center;
}
.back img {
    width: 18px;
    height: 18px;
}
.title {
    font-size: 16px;
    font-weight: bold;
}
.content {
    padding: 10px;
    font-size: 15px;
    color: #333;
    padding-top: 54px;
}