--description--

In programming, prefixing a variable with is or has is a common practice to signify that the variable represents a boolean value.

Here are a few examples:

let isRunning = true;
let hasCompleted = false;

Declare a variable named isError using let and initialize it with false, allowing for its reassignment later.

Later on in the project, you will update the value of isError if the user provides an invalid input.

--hints--

You should declare an isError variable.

assert.isDefined(isError);

Your isError variable should be set to false.

assert.isFalse(isError);

You should use let to declare your isError variable.

assert.match(code, /let\s+isError\s*=\s*false/g);

--seed--

--seed-contents--

html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="styles.css" />
    <title>Calorie Counter</title>
  </head>
  <body>
    <main>
      <h1>Calorie Counter</h1>
      <div class="container">
        <form id="calorie-counter">
          <label for="budget">Budget</label>
          <input
            type="number"
            min="0"
            id="budget"
            placeholder="Daily calorie budget"
            required
          />
          <fieldset id="breakfast">
            <legend>Breakfast</legend>
            <div class="input-container"></div>
          </fieldset>
          <fieldset id="lunch">
            <legend>Lunch</legend>
            <div class="input-container"></div>
          </fieldset>
          <fieldset id="dinner">
            <legend>Dinner</legend>
            <div class="input-container"></div>
          </fieldset>
          <fieldset id="snacks">
            <legend>Snacks</legend>
            <div class="input-container"></div>
          </fieldset>
          <fieldset id="exercise">
            <legend>Exercise</legend>
            <div class="input-container"></div>
          </fieldset>
          <div class="controls">
            <span>
              <label for="entry-dropdown">Add food or exercise:</label>
              <select id="entry-dropdown" name="options">
                <option value="breakfast" selected>Breakfast</option>
                <option value="lunch">Lunch</option>
                <option value="dinner">Dinner</option>
                <option value="snacks">Snacks</option>
                <option value="exercise">Exercise</option>
              </select>
              <button type="button" id="add-entry">Add Entry</button>
            </span>
          </div>
          <div>
            <button type="submit">
              Calculate Remaining Calories
            </button>
            <button type="button" id="clear">Clear</button>
          </div>
        </form>
        <div id="output" class="output hide"></div>
      </div>
    </main>
    <script src="./script.js"></script>
  </body>
</html>

css

:root {
  --light-grey: #f5f6f7;
  --dark-blue: #0a0a23;
  --fcc-blue: #1b1b32;
  --light-yellow: #fecc4c;
  --dark-yellow: #feac32;
  --light-pink: #ffadad;
  --dark-red: #850000;
  --light-green: #acd157;
}

body {
  font-family: "Lato", Helvetica, Arial, sans-serif;
  font-size: 18px;
  background-color: var(--fcc-blue);
  color: var(--light-grey);
}

h1 {
  text-align: center;
}

.container {
  width: 90%;
  max-width: 680px;
}

h1,
.container,
.output {
  margin: 20px auto;
}

label,
legend {
  font-weight: bold;
}

.input-container {
  display: flex;
  flex-direction: column;
}

button {
  cursor: pointer;
  text-decoration: none;
  background-color: var(--light-yellow);
  border: 2px solid var(--dark-yellow);
}

button,
input,
select {
  min-height: 24px;
  color: var(--dark-blue);
}

fieldset,
label,
button,
input,
select {
  margin-bottom: 10px;
}

.output {
  border: 2px solid var(--light-grey);
  padding: 10px;
  text-align: center;
}

.hide {
  display: none;
}

.output span {
  font-weight: bold;
  font-size: 1.2em;
}

.surplus {
  color: var(--light-pink);
}

.deficit {
  color: var(--light-green);
}

--fcc-editable-region--
const calorieCounter = document.getElementById('calorie-counter');
const budgetNumberInput = document.getElementById('budget');
const entryDropdown = document.getElementById('entry-dropdown');
const addEntryButton = document.getElementById('add-entry');
const clearButton = document.getElementById('clear');
const output = document.getElementById('output');

--fcc-editable-region--

Step 17

--description--

--hints--

--seed--

--seed-contents--