Learn CSS Variables by Building a City Skyline - Step 25

HTML-CSS
1

Tell us what’s happening:

can you please explain the following step with a code of css…

Your code so far

<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">    
  <head>
    <meta charset="UTF-8">
    <title>City Skyline</title>
    <link href="styles.css" rel="stylesheet" />   
  </head>

  <body>
    <div class="background-buildings">
      <div></div>
      <div></div>
      <div class="bb1">
        <div class="bb1a"></div>
        <div class="bb1b"></div>
        <div class="bb1c"></div>
        <div class="bb1d"></div>
      </div>
      <div class="bb2"></div>
      <div class="bb3"></div>
      <div></div>
      <div class="bb4"></div>
      <div></div>
      <div></div>
    </div>
  </body>
</html>

/* file: styles.css */

/* User Editable Region */

:root{
  * {
    border: 1px solid black;
    box-sizing: border-box;
  }

  body {
    height: 100vh;
    margin: 0;
    overflow: hidden;
  }

  .background-buildings {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: flex-end;
    justify-content: space-evenly;
  }

  .bb1 {
    width: 10%;
    height: 70%;
    display: flex;
    flex-direction: column;
    align-items: center;
    --building-color1: #aa80ff;
    --building-color2: #66cc99;
    --building-color3: #cc6699;
  }
}

/* User Editable Region */

.bb1a {
  width: 70%;
  height: 10%;
  background-color: var(--building-color1);
}

.bb1b {
  width: 80%;
  height: 10%;
  background-color: var(--building-color1);
}

.bb1c {
  width: 90%;
  height: 10%;
  background-color: var(--building-color1);
}

.bb1d {
  width: 100%;
  height: 70%;
  background-color: var(--building-color1);
}

.bb2 {
  width: 10%;
  height: 50%;
  background-color: var(--building-color2, green);
}

.bb3 {
  width: 10%;
  height: 55%;
  background-color: var(--building-color3, pink);
}

.bb4 {
  width: 11%;
  height: 58%;
}

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Challenge Information:

Learn CSS Variables by Building a City Skyline - Step 25

3

this is not valid css

:root is an other selector to use, you can’t put other selectors inside it

you need to create the :root selector, in general it goes above all others, and here you create the variables

do not put selectors inside the :root selector