CSS

display div in the same line css

<div class='parent'>
  <div class='child'>child 1</div>
  <div class='child'>child 2</div>
</div>

.parent {
  text-align: center;
}
.child {
  display: inline-block;
  vertical-align: middle;
}

css element same line

#element1 {display:inline-block;margin-right:10px;} 
#element2 {display:inline-block;} 

div same line

#block_container {
    display: flex;
    justify-content: center;
}

div same line

#block_container
{
    text-align:center;
}
#bloc1, #bloc2
{
    display:inline;
}