<style>
.container {
    display: grid;
    background-color: lightsalmon;

    /* Invalid minmax value as can't have a flexible length as a minimum value. */
    grid-template-columns: minmax(1fr, 100px) 1fr 1fr;
}

.one {
    background-color: lightblue;
}

.two {
    background-color: yellowgreen;
}
</style>
<div class="container"><div class="one">1</div><div class="two">2</div></div>