Disallow direction values in linear-gradient() calls that are not valid according to the standard syntax.
.foo { background: linear-gradient(to top, #fff, #000); } /** ↑ * This (optional) first argument is the "direction" */
A valid and standard direction value is one of the following:
to plus a side-or-corner (to top, to bottom, to left, to right; to top right, to right top, to bottom left, etc.)A common mistake (matching outdated non-standard syntax) is to use just a side-or-corner without the preceding to.
trueThe following patterns are considered violations:
.foo { background: linear-gradient(top, #fff, #000); }
.foo { background: linear-gradient(bottom, #fff, #000); }
.foo { background: linear-gradient(left, #fff, #000); }
.foo { background: linear-gradient(45, #fff, #000); }
.foo { background: linear-gradient(to top top, #fff, #000); }
The following patterns are not considered violations:
.foo { background: linear-gradient(to top, #fff, #000); }
.foo { background: linear-gradient(to bottom right, #fff, #000); }
.foo { background: linear-gradient(45deg, #fff, #000); }
.foo { background: linear-gradient(1.57rad, #fff, #000); }
/* Direction defaults to "to bottom" */ .foo { background: linear-gradient(#fff, #000); }