Split screen

HTML

<div class="split-screen">
    <!-- Left content -->
    <div class="split-screen__half">
        ...
    </div>

    <!-- Right content -->
    <div class="split-screen__half">
        ...
    </div>
</div>

CSS

.split-screen {
    display: flex;
}

.split-screen__half {
    flex: 1;
}