.index-header {
    position: fixed;
    z-index: 1;
    top: 0;
}
.ui.basic.segment {
    background: #f9f9f9;
}
.ui.container {
    margin-top: 100px;
    background: #fff;
    padding: 1rem;
}
.fixed-dom {
    width: 324px;
    position: fixed;
}
.fixed-dom .ui.header {
    display: flex;
    justify-content: space-between;
}
.changeTopic {
    font-size: 14px;
    color: #666;
}
.changeTopic .ui.icon {
    position: relative;
    left: 8px;
}