.settings-layout {
    display: flex;
}

.settings-sidebar {
    width: 250px;
    background: #eee;
    color: #222;
    display: flex;
    flex-direction: column;
    border: 1px solid #ddd;
}
.settings-sidebar button {
    padding: 12px;
    border: none;
    background: none;
    color: inherit;
    text-align: center;
    cursor: pointer;
}
.settings-sidebar button.active {
    background: #fc4557;
    color: #fff;
    font-weight: bold;
}
.settings-content, .settings-custom-pages {
    flex: 1;
    width: 100%;
    padding: 20px;
}

.settings-custom-pages {
    display: none;
}

.settings-content .single-field {
    display: none;
}

.settings-custom-page {
    display: none;
}