Table of Contents for
Responsive Web Design with HTML5 and CSS3 - Second Edition

Version ebook / Retour

Cover image for bash Cookbook, 2nd Edition Responsive Web Design with HTML5 and CSS3 - Second Edition by Ben Frain Published by Packt Publishing, 2015
  1. Cover
  2. Table of Contents
  3. Responsive Web Design with HTML5 and CSS3 Second Edition
  4. Responsive Web Design with HTML5 and CSS3 Second Edition
  5. Credits
  6. About the Author
  7. About the Reviewers
  8. www.PacktPub.com
  9. Preface
  10. What you need for this book
  11. Who this book is for
  12. Conventions
  13. Reader feedback
  14. Customer support
  15. 1. The Essentials of Responsive Web Design
  16. Defining responsive web design
  17. Setting browser support levels
  18. Our first responsive example
  19. The shortcomings of our example
  20. Summary
  21. 2. Media Queries – Supporting Differing Viewports
  22. Media query syntax
  23. Combining media queries
  24. Using media queries to alter a design
  25. Considerations for organizing and authoring media queries
  26. Combine media queries or write them where it suits?
  27. The viewport meta tag
  28. Media Queries Level 4
  29. Summary
  30. 3. Fluid Layouts and Responsive Images
  31. Introducing Flexbox
  32. Getting Flexy
  33. Responsive images
  34. Summary
  35. 4. HTML5 for Responsive Web Designs
  36. Starting an HTML5 page the right way
  37. Easy-going HTML5
  38. New semantic elements in HTML5
  39. HTML5 text-level semantics
  40. Obsolete HTML features
  41. Putting HTML5 elements to use
  42. WCAG and WAI-ARIA for more accessible web applications
  43. Embedding media in HTML5
  44. Responsive HTML5 video and iFrames
  45. A note about 'offline first'
  46. Summary
  47. 5. CSS3 – Selectors, Typography, Color Modes, and New Features
  48. Anatomy of a CSS rule
  49. Quick and useful CSS tricks
  50. Word wrapping
  51. Facilitating feature forks in CSS
  52. New CSS3 selectors and how to use them
  53. CSS3 structural pseudo-classes
  54. CSS custom properties and variables
  55. CSS calc
  56. CSS Level 4 selectors
  57. Web typography
  58. New CSS3 color formats and alpha transparency
  59. Summary
  60. 6. Stunning Aesthetics with CSS3
  61. Box shadows
  62. Background gradients
  63. Repeating gradients
  64. Background gradient patterns
  65. Multiple background images
  66. High-resolution background images
  67. CSS filters
  68. A warning on CSS performance
  69. Summary
  70. 7. Using SVGs for Resolution Independence
  71. The graphic that is a document
  72. Creating SVGs with popular image editing packages and services
  73. Inserting SVGs into your web pages
  74. Inserting an SVG inline
  75. What you can do with each SVG insertion method (inline, object, background-image, and img)
  76. Extra SVG capabilities and oddities
  77. Animating SVG with JavaScript
  78. Optimising SVGs
  79. Using SVGs as filters
  80. A note on media queries inside SVGs
  81. Summary
  82. 8. Transitions, Transformations, and Animations
  83. CSS3 2D transforms
  84. CSS3 3D transformations
  85. Animating with CSS3
  86. Summary
  87. 9. Conquer Forms with HTML5 and CSS3
  88. Understanding the component parts of HTML5 forms
  89. HTML5 input types
  90. How to polyfill non-supporting browsers
  91. Styling HTML5 forms with CSS3
  92. Summary
  93. 10. Approaching a Responsive Web Design
  94. View and use the design on real devices
  95. Embracing progressive enhancement
  96. Defining a browser support matrix
  97. Tiering the user experience
  98. Linking CSS breakpoints to JavaScript
  99. Avoid CSS frameworks in production
  100. Coding pragmatic solutions
  101. Use the simplest code possible
  102. Hiding, showing, and loading content across viewports
  103. Validators and linting tools
  104. Performance
  105. The next big things
  106. Summary
  107. Index

Considerations for organizing and authoring media queries

We will take a brief tangent at this point to consider some of the different approaches that authors can take when writing and organizing their media queries. Each approach offers some benefits and some tradeoffs so it's worth at least knowing about these factors, even if you decide they are largely irrelevant for your needs.

Linking to different CSS files with media queries

From a browser perspective, CSS is considered to be a 'render blocking' asset. The browser needs to fetch and parse a linked CSS file before rendering of the page can complete.

However, modern browsers are smart enough to discern which style sheets (linked with media queries in the head) need to be analyzed immediately and which can be deferred until after the initial page rendering.

For these browsers, CSS files linked to with non-applicable media queries (for example if the screen is too small for the media query to apply) can be 'deferred' until after the initial page load, providing some performance advantage.

There's more on this topic over on Google's developer pages: https://developers.google.com/web/fundamentals/performance/critical-rendering-path/render-blocking-css

However, I would like to draw your attention to this part in particular:

"...note that "render blocking" only refers to whether the browser will have to hold the initial rendering of the page on that resource. In either case, the CSS asset is still downloaded by the browser, albeit with a lower priority for non-blocking resources."

To reiterate, all the linked files will still be downloaded, the browser just won't hold up rendering of the page if they don't immediately apply.

Therefore, a modern browser loading a responsive web page (take a look at example_02-03) with four different style sheets linked with different media queries (to apply different styles for different viewport ranges) will download all four CSS files but probably only parse the applicable one initially before rendering the page.

The practicalities of separating media queries

Although we have just learned that the process of splitting media queries potentially offers some benefit, there is not always a large tangible advantage (apart from personal preference and/or compartmentalization of code) in separating different media query styles into separate files.

After all, using separate files increases the number of HTTP requests needed to render a page, which in turn can make the pages slower in certain other situations. Nothing is ever easy on the Web! It's therefore really a question of evaluating the entire performance of your site and testing each scenario on different devices.

My default stance on this is that, unless the project has considerable time available for performance optimizations, this is one of the last places I would look to make performance gains. Only once I am certain that:

  • All images are compressed
  • All scripts are concatenated and minified
  • All assets are being served gzipped
  • All static content is being cached via CDNs
  • All surplus CSS rules have been removed

Perhaps then I would start looking to split up media queries into separate files for performance gains.

Tip

gzip is a compression and decompression file format. Any good server should allow gzip for files such as CSS and this greatly decreases the size of the file as it travels from server to device (at which point it is decompressed to its native format). You can find a good summary of gzip on Wikipedia: http://en.wikipedia.org/wiki/Gzip

Nesting media queries 'inline'

In all but extreme circumstances, I recommend adding media queries within an existing style sheet alongside the 'normal' rules.

If you are happy to do the same, it leads to one further consideration: should media queries be declared underneath the associated selector? Or split off into a separate block of code at the end for all identical media queries? I'm glad you asked.