OK, my answer is super nice:
<style>
#wrapper {
display:flex;
width:100%;
align-content: streach;
justify-content: space-between;
}
#wrapper div {
height:100px;
}
.static240 {
flex: 0 0 240px;
}
.static160 {
flex: 0 0 160px;
}
.growMax {
flex-grow: 1;
}
</style>
<div id="wrapper">
<div class="static240" style="background:red;" > </div>
<div class="static160" style="background: green;" > </div>
<div class="growMax" style="background:yellow;" ></div>
</div>
if you wanna support for all browser, use https://github.com/10up/flexibility