Answers for "css draw underline"

underline text using css

/* Using 'text-decoration' property with 'underline' value. we can draw underline below the text using css */
<style>
p {
  text-decoration: underline;
}
</style>
<p>Hello all Welcome here !!!</p>

add expanding underline on page load css

#sec {
  display: inline-block;
  position: relative;
  padding-bottom: 3px;
}
#sec:after {
  content: '';
  display: block;
  margin: auto;
  height: 3px;
  width: 0px;
  background: transparent;
  transition: width .5s ease, background-color .5s ease;
}
#sec:hover:after {
  width: 100%;
  background: blue;
}