background repeat

/* Keyword values */
background-repeat: repeat-x;
background-repeat: repeat-y;
background-repeat: repeat;
background-repeat: space;
background-repeat: round;
background-repeat: no-repeat;

/* Two-value syntax: horizontal | vertical */
background-repeat: repeat space;
background-repeat: repeat repeat;
background-repeat: round space;
background-repeat: no-repeat round;

/* Global values */
background-repeat: inherit;
background-repeat: initial;
background-repeat: revert;
background-repeat: unset;

div {
  background-image: url("alert.png");
  background-repeat: no-repeat;
}

<repeat-style>#
where 
<repeat-style> = repeat-x | repeat-y | [ repeat | space | round | no-repeat ]{1,2}