:root {
    --tc-background: #fff;
    --tc-text-color: #000;
}
html, body {
    padding: 0;
    margin: 0;
}
.page {
    background:var(--tc-background);
    color: var(--tc-text-color);
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-content: center;
    justify-content: center;
    text-align: center;
}
button {
    width: 100px;
    height: 50px;
    cursor: pointer;
}
.theme-list-wrap {
    margin-bottom: 80px;
}
.theme-item {
    height: 40px;
    padding: 0 20px;
    line-height: 40px;
    text-align: center;
    display: inline-block;
    margin: 0 10px;
    background-color: #bfa;
    color: #ff0000;
    font-weight: 500;
    cursor: pointer;
}