Learn CSS Variables by Building a City Skyline - Step 77

Tell us what’s happening:
Describe your issue in detail here.

  **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 building-wrap">
      <div class="bb1a bb1-window"></div>
      <div class="bb1b bb1-window"></div>
      <div class="bb1c bb1-window"></div>
      <div class="bb1d"></div>
    </div>
    <div class="bb2">
      <div class="bb2a"></div>
      <div class="bb2b"></div>
    </div>
    <div class="bb3"></div>
    <div></div>
    <div class="bb4 building-wrap">
      <div class="bb4a"></div>
      <div class="bb4b"></div>
      <div class="bb4c window-wrap">
        <div class="bb4-window"></div>
        <div class="bb4-window"></div>
        <div class="bb4-window"></div>
        <div class="bb4-window"></div>
      </div>
    </div>
    <div></div>
    <div></div>
  </div>

  <div class="foreground-buildings">
    <div></div>
    <div></div>
    <div class="fb1 building-wrap">
      <div class="fb1a"></div>
      <div class="fb1b"></div>
      <div class="fb1c"></div>
    </div>
    <div class="fb2"></div>
    <div></div>
    <div class="fb3"></div>
    <div class="fb4"></div>
    <div class="fb5"></div>
    <div class="fb6"></div>
    <div></div>
    <div></div>
  </div>
</body>
</html>
/* file: styles.css */
:root {
--building-color1: #aa80ff;
--building-color2: #66cc99;
--building-color3: #cc6699;
--building-color4: #538cc6;
--window-color1: black;
--window-color2: #8cd9b3;
--window-color3: #d98cb3;
--window-color4: #8cb3d9;
}

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

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

.background-buildings, .foreground-buildings {
width: 100%;
height: 100%;
display: flex;
align-items: flex-end;
justify-content: space-evenly;
position: absolute;
top: 0;
}

.building-wrap {
display: flex;
flex-direction: column;
align-items: center;
}

.window-wrap {
display: flex;
align-items: center;
justify-content: space-evenly;
}

/* BACKGROUND BUILDINGS - "bb" stands for "background building" */
.bb1 {
width: 10%;
height: 70%;
}

.bb1a {
width: 70%;
}

.bb1b {
width: 80%;
}

.bb1c {
width: 90%;
}

.bb1d {
width: 100%;
height: 70%;
background: linear-gradient(
    var(--building-color1) 50%,
    var(--window-color1)
  );
}

.bb1-window {
height: 10%;
background: linear-gradient(
    var(--building-color1),
    var(--window-color1)
  );
}

.bb2 {
width: 10%;
height: 50%;
}

.bb2a {
border-bottom: 5vh solid var(--building-color2);
border-left: 5vw solid transparent;
border-right: 5vw solid transparent;
}

.bb2b {
width: 100%;
height: 100%;
background: repeating-linear-gradient(
    var(--building-color2),
    var(--building-color2) 6%,
    var(--window-color2) 6%,
    var(--window-color2) 9%
  );
}

.bb3 {
width: 10%;
height: 55%;
background: repeating-linear-gradient(
    90deg,
    var(--building-color3),
    var(--building-color3),
    var(--window-color3) 15%
  );
}

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

.bb4a {
width: 3%;
height: 10%;
background-color: var(--building-color4);
}

.bb4b {
width: 80%;
height: 5%;
background-color: var(--building-color4);
}

.bb4c {
width: 100%;
height: 85%;
background-color: var(--building-color4);
}

.bb4-window {
width: 18%;
height: 90%;
background-color: var(--window-color4);
}

/* FOREGROUND BUILDINGS - "fb" stands for "foreground building" */
.fb1 {
width: 10%;
height: 60%;
}

.fb1b {
width: 60%;
height: 10%;
background-color: var(--building-color4);
}
.fb1c {
width: 100%;
height: 80%;
background: repeating-linear-gradient(
  90deg,
  var(--building-color4) 10%,
  transparent 15%
)

}
.fb2 {
width: 10%;
height: 40%;
background-color: var(--building-color3);
}

.fb3 {
width: 10%;
height: 35%;
background-color: var(--building-color1);
}

.fb4 {
width: 8%;
height: 45%;
background-color: var(--building-color1);
position: relative;
left: 10%;
}

.fb5 {
width: 10%;
height: 33%;
background-color: var(--building-color2);
position: relative;
right: 10%;
}

.fb6 {
width: 9%;
height: 38%;
background-color: var(--building-color3);
}
  
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.5060.134 Safari/537.36 Edg/103.0.1264.77

Challenge: Learn CSS Variables by Building a City Skyline - Step 77

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