Which option is more effective: using an id or using !important?

Question

Which option is more effective: using an id or using !important?

While some say to avoid using the !important rule and others argue that since ids are unique, there is no need to target like #main > #child and you can simply use #child.

In my particular case:

#main > div{
   color: red;
}
#child{
  color: blue;/*won't override*/
}

However, using !important will override.
Alternatively, using #main > #child{ will also override.

So, which approach is preferable in this scenario?

css css-selectors

Answer 1

Answer №1

Understanding the order of CSS rules is crucial:

#main > div{
   color: red;
}
#main > div{ /*last defined rule*/
  color: blue; /*will override*/
}

Let's address your main question:

Using !important can be useful in certain situations. Refer to this code from a comment on css-tricks by Marco Campos:

I used it in a specific scenario to fix an overflow issue in IE9 while keeping other browsers intact. Despite recommending browser upgrade, I had to use !important for proper rendering in IE9.

body {
    overflow:auto !important; /* for all other browsers, the !important is for IE9 */
    overflow:hidden\9; /* for IE<9 */
}

Now, let's delve into how CSS selectors operate:

The style system prioritizes matching rules starting with the key selector, then moving leftward (checking ancestors in the selector). The faster resolution results from minimal rule checks required for each element.

For instance, an element with an ID only checks ID rules and so forth. Universal Rules are always scanned.

Hence, using #main > #child is less efficient than just #child. Avoid the former for better performance.

Consider utilizing parent element selectors for overrides without !important:

body #child{
    color: purple !important;
}

An alternative approach without multiple id selectors or !important:

body div#child{ 
    color: blue; /*will override*/
}

A simpler solution involves classes:

.parent-class #child{
    color: blue; /* will take precedence*/
}
#main > div{
    color: red;
}

Note: Avoid using !important in inline styles as it hinders overrides.

<div style="color: blue !important;">color is always blue</div>

In the dilemma between #main > #child{color: blue;} and #child{color: blue !important;}, prioritize the latter for ease of override and better efficiency.

Answer 2

Understanding the order of CSS rules is crucial:

#main > div{
   color: red;
}
#main > div{ /*last defined rule*/
  color: blue; /*will override*/
}

Let's address your main question:

Using !important can be useful in certain situations. Refer to this code from a comment on css-tricks by Marco Campos:

I used it in a specific scenario to fix an overflow issue in IE9 while keeping other browsers intact. Despite recommending browser upgrade, I had to use !important for proper rendering in IE9.

body {
    overflow:auto !important; /* for all other browsers, the !important is for IE9 */
    overflow:hidden\9; /* for IE<9 */
}

Now, let's delve into how CSS selectors operate:

The style system prioritizes matching rules starting with the key selector, then moving leftward (checking ancestors in the selector). The faster resolution results from minimal rule checks required for each element.

For instance, an element with an ID only checks ID rules and so forth. Universal Rules are always scanned.

Hence, using #main > #child is less efficient than just #child. Avoid the former for better performance.

Consider utilizing parent element selectors for overrides without !important:

body #child{
    color: purple !important;
}

An alternative approach without multiple id selectors or !important:

body div#child{ 
    color: blue; /*will override*/
}

A simpler solution involves classes:

.parent-class #child{
    color: blue; /* will take precedence*/
}
#main > div{
    color: red;
}

Note: Avoid using !important in inline styles as it hinders overrides.

<div style="color: blue !important;">color is always blue</div>

In the dilemma between #main > #child{color: blue;} and #child{color: blue !important;}, prioritize the latter for ease of override and better efficiency.

Answer 3

Answer №2

Take a look at this helpful explanation. It provides insight into the rule order.

It is advisable to steer clear of using !important as it holds the highest priority and could lead to complications if you need to override it.

My recommendation for you would be #main > #child

Answer 4

Take a look at this helpful explanation. It provides insight into the rule order.

It is advisable to steer clear of using !important as it holds the highest priority and could lead to complications if you need to override it.

My recommendation for you would be #main > #child

Answer 5

Answer №3

Focusing on the concept rather than the content is the key to effective styling.

For example, instead of directly setting something to be red, it's better to approach it like this:

<div class="red"></div>

And then in your CSS:

.red{
    background-color: red;
}

If you need additional properties like size or width:

<div class="big red">

And in your CSS:

.big{
    font-size: 2em;
}
.red{
    background-color: red;
}

Furthermore, if you ever need to override a style, using !important is a better practice. This helps avoid relying on IDs for styling and reserves them for JavaScript DOM manipulation purposes :)

To Elaborate Further

Consider this suboptimal design:

HTML

<div id="main">
    <div id="child">
    </div>
</div>

CSS

#main{
    font-size: 2em;
    background-color: red;
}
#main > #child{
    font-size: 1.5em;
    background-color: blue;
}

This approach has its drawbacks:

What happens if you decide to reorganize the hierarchy of elements later on? Creating flexibility can be challenging with such specific targeting.

What does main:red or

main:2em</code really signify conceptually? It's more beneficial to think in terms of <code>red:red

& big:2em combinations for adaptability.

Answer 6

Focusing on the concept rather than the content is the key to effective styling.

For example, instead of directly setting something to be red, it's better to approach it like this:

<div class="red"></div>

And then in your CSS:

.red{
    background-color: red;
}

If you need additional properties like size or width:

<div class="big red">

And in your CSS:

.big{
    font-size: 2em;
}
.red{
    background-color: red;
}

Furthermore, if you ever need to override a style, using !important is a better practice. This helps avoid relying on IDs for styling and reserves them for JavaScript DOM manipulation purposes :)

To Elaborate Further

Consider this suboptimal design:

HTML

<div id="main">
    <div id="child">
    </div>
</div>

CSS

#main{
    font-size: 2em;
    background-color: red;
}
#main > #child{
    font-size: 1.5em;
    background-color: blue;
}

This approach has its drawbacks:

What happens if you decide to reorganize the hierarchy of elements later on? Creating flexibility can be challenging with such specific targeting.

What does main:red or

main:2em</code really signify conceptually? It's more beneficial to think in terms of <code>red:red

& big:2em combinations for adaptability.

Answer 7

Answer №4

It's advisable to steer clear of using !important; I recommend going with your second choice instead. Using !important can make it challenging to implement future changes in your CSS.

The only way to override an "!important" rule is by specifying another one further down, with a selector that has the same or higher level of specificity.

Answer 8

It's advisable to steer clear of using !important; I recommend going with your second choice instead. Using !important can make it challenging to implement future changes in your CSS.

The only way to override an "!important" rule is by specifying another one further down, with a selector that has the same or higher level of specificity.

Which option is more effective: using an id or using !important?

Answer №1

Let's address your main question:

Answer №2

Answer №3

Answer №4

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