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curriculum/challenges/english/blocks/learn-intermediate-oop-by-building-a-platformer-game/6461b0b3dc4034f4f70a4929.md

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--description--

Before you can begin building out the functionality for the game, you will need to set up the ability to add 2D graphics.

The <dfn>Canvas API</dfn> can be used to create graphics in games using JavaScript and the HTML canvas element.

You will need to use the getContext method which will provide the context for where the graphics will be rendered.

js
canvas.getContext("2d");

Assign that getContext method to a const variable called ctx.

--hints--

You should use the canvas.getContext("2d") method.

js
assert.match(code, /canvas\.getContext\(\s*('|"|`)2d\1\s*\)/);

You should use const to declare the variable called ctx and assign it canvas.getContext("2d").

js
assert.match(code, /const\s+ctx\s*=\s*canvas\.getContext\(\s*('|"|`)2d\1\s*\)/);

--seed--

--seed-contents--

html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Learn Intermediate OOP by Building a Platformer Game</title>
    <link rel="stylesheet" href="./styles.css" />
  </head>
  <body>
    <div class="start-screen">
      <h1 class="main-title">freeCodeCamp Code Warrior</h1>
      <p class="instructions">
        Help the main player navigate to the yellow checkpoints.
      </p>
      <p class="instructions">
        Use the keyboard arrows to move the player around.
      </p>
      <p class="instructions">You can also use the spacebar to jump.</p>

      <div class="btn-container">
        <button class="btn" id="start-btn">Start Game</button>
      </div>
    </div>

    <div class="checkpoint-screen">
      <h2>Congrats!</h2>
      <p>You reached the last checkpoint.</p>
    </div>

    <canvas id="canvas"></canvas>

    <script src="./script.js"></script>
  </body>
</html>

css
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --main-bg-color: #0a0a23;
  --section-bg-color: #ffffff;
  --golden-yellow: #feac32;
}

body {
  background-color: var(--main-bg-color);
}

.start-screen {
  background-color: var(--section-bg-color);
  width: 100%;
  position: absolute;
  top: 50%;
  left: 50%;
  margin-right: -50%;
  transform: translate(-50%, -50%);
  border-radius: 30px;
  padding: 20px;
  padding-bottom: 5px;
}

.main-title {
  text-align: center;
}

.instructions {
  text-align: center;
  font-size: 1.2rem;
  margin: 15px;
  line-height: 2rem;
}

.btn {
  cursor: pointer;
  width: 100px;
  margin: 10px;
  color: #0a0a23;
  font-size: 18px;
  background-color: var(--golden-yellow);
  background-image: linear-gradient(#fecc4c, #ffac33);
  border-color: var(--golden-yellow);
  border-width: 3px;
}

.btn:hover {
  background-image: linear-gradient(#ffcc4c, #f89808);
}

.btn-container {
  display: flex;
  align-items: center;
  justify-content: center;
}

.checkpoint-screen {
  position: absolute;
  left: 0;
  right: 0;
  margin-left: auto;
  margin-right: auto;
  width: 100%;
  text-align: center;
  background-color: var(--section-bg-color);
  border-radius: 20px;
  padding: 10px;
  display: none;
}

#canvas {
  display: none;
}

@media (min-width: 768px) {
  .start-screen {
    width: 60%;
    max-width: 700px;
  }

  .checkpoint-screen {
    max-width: 300px;
  }
}

js
const startBtn = document.getElementById("start-btn");
const canvas = document.getElementById("canvas");
const startScreen = document.querySelector(".start-screen");
const checkpointScreen = document.querySelector(".checkpoint-screen");
const checkpointMessage = document.querySelector(".checkpoint-screen > p");

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