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HTML5 `<canvas>` Element Not Resizing Properly When Using CSS Flexbox - Seeking Best Practices

πŸ‘€ Views: 28 πŸ’¬ Answers: 1 πŸ“… Created: 2025-06-21
html css canvas flexbox HTML

I'm deploying to production and I'm facing an issue with an HTML5 `<canvas>` element that should resize responsively within a flexbox layout..... The canvas is meant to take up the full width of its container and maintain its aspect ratio, but I'm noticing some unexpected behavior. When I resize the browser window, the canvas doesn't adjust its dimensions correctly, leading to visual distortion of the drawn content. Here's a simplified version of my code: ```html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .container { display: flex; justify-content: center; align-items: center; height: 100vh; } canvas { width: 100%; height: auto; } </style> </head> <body> <div class="container"> <canvas id="myCanvas" width="800" height="600"></canvas> </div> <script> const canvas = document.getElementById('myCanvas'); const ctx = canvas.getContext('2d'); ctx.fillStyle = 'blue'; ctx.fillRect(10, 10, 200, 100); </script> </body> </html> ``` Despite setting the CSS width to 100%, the canvas seems to be using its initial width and height attributes to determine its rendering size, which causes the content to appear squished or stretched when the window is resized. I've tried removing the `width` and `height` attributes directly from the `<canvas>` tag, but then the canvas ends up with default sizes, which doesn't help my layout. I've also looked into using the `resize` event to manually adjust the canvas dimensions in JavaScript, but that feels like a workaround rather than a proper solution. Am I missing a key concept about how to properly style HTML5 canvas elements within a flexbox layout? What’s the best practice to ensure it resizes correctly while preserving the aspect ratio? Any insights would be appreciated! For context: I'm using Html on macOS. I'd really appreciate any guidance on this. This is happening in both development and production on Ubuntu 20.04.