Answers for "background radius"

css rounded corners

/* Set rounded corners with border-radius property */

.class {
  border-radius: 4px;
}

.circle {
  border-radius: 50%;
}

css scaling border radius

// to scale a border-radius based upon the element size it is nested in. (rounded corners)
// simply change the vw number from .1 to 10 or whatever to change the amount of curve.
#box1 {
  border-radius: 2vw;
}

css border radius

-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;