10 CSS Rules Every Web Designer Should Know

10 CSS Rules Every Web Designer Should Know
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Through experience as web designers we memorise all kinds of code syntax, hacks and snippets. With CSS in particular there is a number of rules and declarations that can really help transform your website designs and open up new possibilities when compared to older techniques. This post rounds up 10 declarations and tips that every web designer should have available in their CSS arsenal.


@media screen and (max-width: 960px) {


The @media rule not only allows you to specify styling for your web page when printed. These days media queries are more associated with the creation of responsive or adaptive website designs. Create a media query using properties such as min-width to adjust your design according to the user’s viewport size.


body {
	background: url(image.jpg) no-repeat;
	background-size: 100%;

A cool and extremely useful CSS3 property that has now gained thorough browser support is background-size. At one point making a background scale to the size of its parent required some right messing around, but now just one line of code is all you need. Use this snippet to achieve the ever-popular full screen background image effect.


@font-face {
	font-family: Blackout;
	src: url("assests/blackout.ttf") format("truetype");

One CSS3 property that has really helped transform the web over recent years is @font-face. We previously had all kinds of limitations regarding font licensing which held back this property, but now there’s bucket loads of fonts to choose from and a range of services that build upon the basic @font-face code. Use @font-face manually with freely available fonts, or via third party services such as Google Webfonts or Typekit.

margin: 0 auto;

#container {
	margin: 0 auto;

The clever margin: 0 auto; declaration is one of the first snippets you learn when getting to grips with CSS. It’s surprising that no specific declaration for centering a block element was ever added to the CSS spec, but instead we’ve all come to rely on the auto margin workaround. Add margin: 0 auto; to centre any block element within its parent.

overflow: hidden

.container {
	overflow: hidden;

There’s all kinds of float clearing solutions and hacks out there, but one pure and simple way to clear your floats is to simply use the overflow: hidden; declaration on the container of your floated elements. It doesn’t add a load of garbage to your stylesheet and it gets the job done in 90% of scenarios.


.clearfix:after {
	content: ".";
	display: block;
	clear: both;
	visibility: hidden;
	line-height: 0;
	height: 0;

For those float clearing situations where overflow: hidden; doesn’t work, the best alternative is the clearfix technique. Remember you don’t have to use the clearfix class name, your could target this code to any of your HTML elements individually.

color: rgba();

.btn {
	color: rgba(0,0,0,0.5);

PNG images used to be required for creating any kind of transparency effects in web design, but thanks to another advance in CSS transparency can now be created with the help of the RGBa color mode. Using RGBa in place of a hex value allows you to select a colour using its red, green and blue channels as well as setting an alpha level, such as 0.5 for 50% opacity.


input[type="text"] {
	width: 200px;

The input[type="text"] selector and advanced selectors as a whole are great for taking your CSS skills from intermediate to expert. Attribute selectors in particular are extremely useful for styling elements without the need for additional classes. What about using attribute selectors to target the submit version of an input element or add an icon to external links?

transform: rotate(30deg);

.title {
	transform: rotate(30deg);

If I’m honest I’ve yet to find a use for CSS transform properties in a real design project, but the ability to manipulate HTML elements without Javascript is so cool it makes these properties worth remembering! Combine transform properties with CSS transitions to create some fun animation effects.

a {outline: none;}

a {outline: none;}

Nothing can spoil a design more than seeing a huge dotted outline spanning across the whole page when you click a link element. The a {outline: none;} declaration will remove this, but for accessibility don’t forget to also add :focus states to your links. If you don’t mind seeing the dotted border but wish it didn’t span the whole screen, just add a {overflow: auto; } to your stylesheet instead.

Written by Iggy

Iggy is a designer who loves experimenting with new web design techniques, collating creative website designs, and writing about the latest design trends, inspiration, design freebies, and more. You can follow him on Twitter


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  1. Troy Thibodeaux says:

    At this point, these are oldies, but goodies. The IE8 discussion is less relevant now, but it still rears it’s ugly head from time to time.

    I just recently started following line25 and has become a great resource.

  2. Rakhi Dhavale says:

    helpful! thanks!

  3. Gareth says:

    Great list, thanks for sharing! Some of these are really helpful.

  4. Pixon design says:

    Great post. A perfect info source. Thanks for taking the time to discuss this, I feel strongly about it and love learning more on this topic. I desired to be able to many thanks because of this outstanding examine!!

  5. Richard says:

    Great. The clearfix is great thanks for sharing.

  6. Dustin Ryen says:

    Great post! I found it very informative.

  7. Ray says:

    Thanks for sharing! Can you indicate which are CSS3 specific?

  8. John Mulligan says:

    Very useful, Got a couple nice tips from this list.

  9. Danny says:

    I don't quite get the .clearfix stuff – but I guess I'll research. Otherwise great post, very useful. Keep it up!

  10. mark says:

    thanks for the share a big big help thanks again….

  11. Osho Garg says:

    Great Work, I Am Currently Learning CSS3 And HTML5 But 9 Of Them Rules Are New To Me :)

  12. Rudi says:

    Some are new for me, tq for share this stuff, hope you write more about CSS in the future

  13. Rafael H says:

    as a fan of the keyboard use,
    i am really against the 'outline:0' css… maybe it makes your design cleaner, but as soon as i will see i cannot use the keyboard, i will leave your site.

  14. Justin says:

    The font-face didn't work for me. I wonder why.

  15. Jump Web Design says:

    multiple backgrounds will be incredibly helpful when it is eventually whole-heartedly supported.

    text-overflow too, instead of using PHP to truncate strings.

  16. Cgizma says:

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    <a href="” >Los Angeles IT Services </a> need stylish blog design so thanks!

  18. Michael says:

    Good stuff. Thanks for sharing. Pretty basic stuff, but always a nice refresh.

  19. Mike says:

    Nice always good to remember basics.. no relation to this is article i just wanted to say your blog rock simple and clean but the best so far seriously .
    I compare all the webdesign blogs and you always come out with something different than the others thats what make it so good . keep it up

  20. Design Russia says:

    Waht a nice blog you have! Really enjoyed reading all your posts about web design. From my point of view, it's important to follow above mentioned CSS rules, as they help a lot to keep up with website usability!

  21. Sean says:

    I'm one of the older schooled web developers where to clear floated elements you just created a class called "clearboth" and then inserted an empty div using that class. For me this is what works 100% of the time. The "clearfix" method I haven't used very often mainly because I've found several places where it absolutely does not work. I can't explain why it doesn't work, just that it simply does not work for me at least half the time.

    The project I'm currently working is using a predefined template that uses the clearfix method. I've had several elements (usually divs) that are floated for one reason or another. I first tried using the clearfix on them so that any following elements would line up correctly but at least 50% of the time absolutely nothing came of using clearfix. However as soon as I removed the clearfix class and then inserted a div with a normal clearboth class after the floated elements, everything lined up just fine.

    So I don't currently see myself using the clearfix method anymore. I mean why use it if it doesn't work?

  22. Naz says:

    Great stuff. Thanks

  23. darshan says:

    Few more useful CSS3 rules:




  24. Alex > says:

    great article. i'm definatley going to use at least one method in my next project.

  25. Daru Sim says:

    Very informative! Thanks!

  26. Webdesign Lover says:

    CSS can be a bit daunting for one if one is just getting started. And the post has shared the most important CSS rules that helps to one and give the better understanding of how to use CSS. Great job you have done my friend…

  27. Thomas says:

    Brilliant CSS recommendations has made sourcing good content for reading and blogging much better, also some great inspiration in there.

  28. Molana says:

    agree,.. we have to know that
    thank for share

  29. Webmastericons says:

    Great CSS recommendations. This is definitely helpful. Thanks.

  30. Niraj says:

    How to avoid over lapping of the Divisions when browser window is resized?

  31. Devon Gilchrist says:

    Though only partially supported via vendor prefix at the moment, CSS3 flexbox gives the ability to center elements vertically & horizontally without the use of {margin: 0 auto;} ref. &

  32. umashankar says:

    Awesome stuff :)

  33. Alex Braker says:

    I have applied all the rules in my design which you have given here. The best rule is color:rgba() and by using this property you can easily give the transparency into your web design.

  34. saha says:

    I apply most of the listed rules. There are few rules which I have not used commonly. But I'll try to used them. Every web designer should learn these rules. Thanks for sharing this useful list.

  35. Anjank says:

    Nice post. I'll learn it

  36. jared says:

    Nice list, definitely things every web designer should learn.

  37. Otter Creative Studio says:

    Simply put: excellent post.

  38. johanso says:

    Ok, well, missing several, but well

  39. Jonathan says:

    I agree with most in your list. I disagree with removing the outline on links for accessibility reasons.

    Another you might consider adding is

    * {
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;

    It has a great pollyfill to support IE all the way back to IE6.

    Here's what Paul Irish and Chris Coyier have to say about border-box:

  40. TM Singh says:

    Great post. Yes, some of them are really interesting and were very new to me.

  41. Edd Turtle says:

    "10 CSS Rules Every Web Designer Should Know" — but should also be aware of their consequences.

    background-size isn't supported by IE8 FYI, neither is rgba & respond.js can be used for media queries.

    • past says:

      no one cares about IE anymore!!

      • Christian Gehrke says:

        Unfortunately, my company does and since we build apps for the company to use, I still need to support ie8.

        • darshan says:

          IE has around 30% market share in the war of browsers.

          So I think microsoft should hire people to make IE CSS3 compatible. :)

    • nichole says:

      I agree. My job has a high percentage of people that use IE because of government regulations and such. It would have been nice if they would have mentioned which rules don't work in IE because not everyone can afford to say "well, download firefox/chrome/safari/etc, it will work there"

  42. Nimsrules says:

    Not all but, yes there were a few which I really didn't know like the outline: none for anchor tags. I thought this worked only for removing those yellow and blue outlines from text inputs. Great share I must add.

  43. Thomas J Bradley says:

    That .clearfix may not work in older IEs and may cause weird display issues. I would use the HTML 5 Boilerplate version:

    .clearfix:after {
    content: "";
    display: table;

    .clearfix:after {
    clear: both;

    .clearfix {
    zoom: 1;

  44. LongYC says:

    I wish we can use hex notation for RGBA as in Android app development. I always prefer hex as it is straight forward and shorter.

  45. Tom says:

    Removing outline is a big accessibility no-no.

  46. Charlie says:

    what exactly is the difference between :
    overflow: hidden and clear:both ?

    • Tigger says:

      Overflow specifies what happens when content overflows its containing box. Clear specifies which side of the element floats are not allowed on. If "clear: both;" is declared, then the floated elements will be forced to stretch out to accomodate their container. You might use clear: both on a footer div to get, say, a sidebar and a main section of a page, which are unequal in height because of their content, to stretch the same amount all the way to the footer. Take a look at for more info. I wish I were better at explaining it. Sorry if I confused you more!

    • Dieter says:

      Overflow:hidden hides any overflow over a parent element while clear:both resets floating structure.

  47. Gareth says:

    Wow there was one or two in there I didn't even know!

    • Bren Murphy says:

      Some powerful coding tips here – always about simplicity and awareness – and being responsible across the whole site.

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