Make plus symbol in CSS [duplicate]

Answer 1

I'd also advise using the actual symbol:

.plus {
  display: block;
  height: 0.6em;
  width: 0.6em;
  font-size: 100px;
  text-align: center;
  line-height: 0.5em;
  margin: 0;
  padding: 0;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  font-family: Frutiger, "Frutiger Linotype", Univers, Calibri, "Gill Sans", "Gill Sans MT", "Myriad Pro", Myriad, "DejaVu Sans Condensed", "Liberation Sans", "Nimbus Sans L", Tahoma, Geneva, "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-weight: lighter;
  color: #ffffff;
  background-color: #000000;
}

.plus::before {
  display: block;
  content: '+';
}

Fiddle: https://jsfiddle.net/m5de0ycL/

Then just change the font-size for size, and if it's not thin enough for you then you can change the font family to a narrower one.

Edit: @Temani-Afif's solution is more diverse. I'd recommend his over mine, depending on your compatibility needs: Make plus symbol in CSS