--description--

The last challenge created a bar chart, but there are a couple of formatting changes that could improve it:

Add space between each bar to visually separate them, which is done by adding a margin to the CSS for the bar class
Increase the height of the bars to better show the difference in values, which is done by multiplying the value by a number to scale the height

--instructions--

First, add a margin of 2px to the bar class in the style tag. Next, change the callback function in the style() method so it returns a value 10 times the original data value (plus the px).

Note: Multiplying each data point by the same constant only alters the scale. It's like zooming in, and it doesn't change the meaning of the underlying data.

--hints--

The first div should have a height of 120 pixels and a margin of 2 pixels.

const firstDiv = document.querySelector('div');
assert.exists(firstDiv); 
const height = window.getComputedStyle(firstDiv)['height'];
const margin = window.getComputedStyle(firstDiv)['margin-right'];
assert.strictEqual(height, '120px');
assert.strictEqual(margin, '2px');

The second div should have a height of 310 pixels and a margin of 2 pixels.

const secondDiv = document.querySelectorAll('div')[1];
assert.exists(secondDiv); 
const height = window.getComputedStyle(secondDiv)['height'];
const margin = window.getComputedStyle(secondDiv)['margin-right'];
assert.strictEqual(height, '310px');
assert.strictEqual(margin, '2px');

The third div should have a height of 220 pixels and a margin of 2 pixels.

const thirdDiv = document.querySelectorAll('div')[2];
assert.exists(thirdDiv); 
const height = window.getComputedStyle(thirdDiv)['height'];
const margin = window.getComputedStyle(thirdDiv)['margin-right'];
assert.strictEqual(height, '220px');
assert.strictEqual(margin, '2px');

The fourth div should have a height of 170 pixels and a margin of 2 pixels.

const fourthDiv = document.querySelectorAll('div')[3];
assert.exists(fourthDiv); 
const height = window.getComputedStyle(fourthDiv)['height'];
const margin = window.getComputedStyle(fourthDiv)['margin-right'];
assert.strictEqual(height, '170px');
assert.strictEqual(margin, '2px');

The fifth div should have a height of 250 pixels and a margin of 2 pixels.

const fifthDiv = document.querySelectorAll('div')[4];
assert.exists(fifthDiv); 
const height = window.getComputedStyle(fifthDiv)['height'];
const margin = window.getComputedStyle(fifthDiv)['margin-right'];
assert.strictEqual(height, '250px');
assert.strictEqual(margin, '2px');

The sixth div should have a height of 180 pixels and a margin of 2 pixels.

const sixthDiv = document.querySelectorAll('div')[5];
assert.exists(sixthDiv); 
const height = window.getComputedStyle(sixthDiv)['height'];
const margin = window.getComputedStyle(sixthDiv)['margin-right'];
assert.strictEqual(height, '180px');
assert.strictEqual(margin, '2px');

The seventh div should have a height of 290 pixels and a margin of 2 pixels.

const seventhDiv = document.querySelectorAll('div')[6];
assert.exists(seventhDiv); 
const height = window.getComputedStyle(seventhDiv)['height'];
const margin = window.getComputedStyle(seventhDiv)['margin-right'];
assert.strictEqual(height, '290px');
assert.strictEqual(margin, '2px');

The eighth div should have a height of 140 pixels and a margin of 2 pixels.

const eighthDiv = document.querySelectorAll('div')[7];
assert.exists(eighthDiv); 
const height = window.getComputedStyle(eighthDiv)['height'];
const margin = window.getComputedStyle(eighthDiv)['margin-right'];
assert.strictEqual(height, '140px');
assert.strictEqual(margin, '2px');

The ninth div should have a height of 90 pixels and a margin of 2 pixels.

const ninthDiv = document.querySelectorAll('div')[8];
assert.exists(ninthDiv); 
const height = window.getComputedStyle(ninthDiv)['height'];
const margin = window.getComputedStyle(ninthDiv)['margin-right'];
assert.strictEqual(height, '90px');
assert.strictEqual(margin, '2px');

--seed--

--seed-contents--

html

<style>
  .bar {
    width: 25px;
    height: 100px;
    /* Add your code below this line */

    
    /* Add your code above this line */
    display: inline-block;
    background-color: blue;
  }
</style>
<body>
  <script>
    const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];

    d3.select('body')
      .selectAll('div')
      .data(dataset)
      .enter()
      .append('div')
      .attr('class', 'bar')
      .style('height', d => d + 'px'); // Change this line
  </script>
</body>

--solutions--