The use of modern HTML5, CSS3 and JavaScript standards is highly encouraged because it helps “future-proof” applications and make updates easier to implement. The main caveat of this recommendation is that new technology is encouraged as long as it works in all officially supported browsers. Therefore, every application and design should be tested in every common browser.
All styles and look & feel should be handled in the CSS and NOT in the HTML code.
Some basic high-level rules to follow are:
- Never style pages with inline CSS. This makes it impossible to override styles using a stylesheet. Semantic HTML should only be used for page structure. All styling should be handled by the CSS.
- Developers should avoid deprecated tags such as “<b>” and “<i>” and use modern tags like “<strong>” and “<em>” instead.
- Tables should NEVER be used for page structure. Tables are difficult to style and scale appropriately. They should only be used for tabular data.
- Use tags properly: For example, “<div>” tags should be used for structure and “<p>” tags should be used for text.
Effort should be made to consistently follow these common best practices.