Bootstrap Put Button em uma linha
<div class="container">
<div class="row">
<div class="col-12 col-md-6">
<form>
<button class="btn btn-primary btn-lg" type="submit" formaction="1klasse.html">1.klasse </button>
</form>
</div>
<div class="col-12 col-md-6">
<form>
<button class="btn btn-primary btn-lg" type="submit" formaction="1klasse.html">1.klasse </button>
</form>
</div>
</div>
</div>
Worrisome Wombat