--- id: 5d822fd413a79914d39e98d7 title: Step 15 challengeType: 0 dashedName: step-15 --- # --description-- To use a variable, put the variable name in parentheses with `var` in front of them like this: `var(--variable-name)`. Add your variable as the value of the `background-color` property of the `.bb1a` class. Whatever value you gave the variable will be applied to whatever property you use it on. In this case, your variable has the value of `#999`. So `#999` will be used as the value for the `background-color` property. # --hints-- The `background-color` of the `bb1a` element should be set. ```js assert.exists(new __helpers.CSSHelp(document).getStyle('.bb1a')?.backgroundColor) ``` You should use `var(--building-color1)` to set the `background-color` of the `.bb1a` element. ```js assert.equal(new __helpers.CSSHelp(document).getStyle('.bb1a')?.backgroundColor.trim(), 'var(--building-color1)'); ``` # --seed-- ## --seed-contents-- ```html City Skyline
``` ```css * { border: 1px solid black; box-sizing: border-box; } body { height: 100vh; margin: 0; overflow: hidden; } .background-buildings { width: 100%; height: 100%; } .bb1 { width: 10%; height: 70%; display: flex; flex-direction: column; align-items: center; --building-color1: #999; } --fcc-editable-region-- .bb1a { width: 70%; height: 10%; } --fcc-editable-region-- .bb1b { width: 80%; height: 10%; } .bb1c { width: 90%; height: 10%; } .bb1d { width: 100%; height: 70%; } ```