AtoZ CSS Quick Tip: Placeholder Text

This article is part of the AtoZ CSS series. You can find other entries for the series here. You can view the full text and screenshots of its corresponding video pseudo-elements.

Welcome to our AtoZ CSS series! In this series, I will explore various CSS values ​​(and properties) that start with different letters in the alphabet. We know that sometimes screenshots are not enough, so in this article we have added a new tip on style placeholder text.

P stands for placeholder text

Pseudo-elements :before and :after are ideal for building complex design features without messing up markups with non-semantic elements. Other pseudo-elements, such as :first-line and :first-letter, allow us to access the style of unmarked elements in HTML documents.

We looked at a lot of these in the pseudo-element screenshot, but one pseudo-element we didn't look at was the style of the placeholder text. Let's solve this problem.

Select input placeholder

First, let's imagine the following HTML:

<input class="name-field" type="text" placeholder="Enter your name">

We can set the color of the input text to red, as shown below:

.name-field {
  color: red;
}

We can also select and set the style of input according to its placeholder attributes:

input[placeholder="Enter your name"] {
  color: red;
}

But this will still style any user input text typed in the input field, rather than setting the appearance of the placeholder text itself. To do this, we need a series of vendor prefix selectors for placeholder pseudo-elements.

::-webkit-input-placeholder {
  color: red;
}
:-moz-placeholder {/*Firefox 18-*/
  color: red;  
}
::-moz-placeholder {/*Firefox 19+*/
  color: red;  
}
:-ms-input-placeholder {  
  color: red;  
}

This looks like a repetition, but unfortunately there is no more concise (Don’t Repeat Yourself) way to do this.

The following method is invalid:

::-webkit-input-placeholder,
:-moz-placeholder,
::-moz-placeholder,
:-ms-input-placeholder {
  color: red;  
}

This is because any browser must be able to "understand" each selector in the comma-separated series in order to apply the styles inside braces.

Set placeholder style with Sass

One way to solve this duplicate CSS is to use Sass hybrid macros. This is what I use in 99% of projects:

@mixin input-placeholder {
  ::-webkit-input-placeholder {
    @content;
  }
  :-moz-placeholder {/* Firefox 18- */
    @content;
  }
  ::-moz-placeholder {/* Firefox 19+ */
    @content;
  }
  :-ms-input-placeholder {  
    @content;
  }
}

/* usage */

@include input-placeholder {
  color: red;
}

This allows me to style placeholders in all browsers using a single Sass @include which helps make the code shorter and easier to maintain.

Pay attention to specificity when setting placeholder style

In IE browser, setting the style entered may override the styles set for placeholder text.

:-ms-input-placeholder {
  color: red;
}
input[type="text"] { 
  color: blue; /* 占位符文本在 IE 中将为蓝色 */
}

Ensure that IE placeholder styles have higher specificity so that they appear as expected. This may even be a case of using !important, but be careful when using this powerful tool.

Pay attention to the opacity of placeholders

In Firefox, the default opacity of placeholder text is about 0.5, so setting opacity: 1 on the placeholder will cause the color to darken unless you also set color: red.

Even if you use Normalize.css, this item will not be reset for you. If completely opaque placeholders are crucial to your project, keep this tip in mind!

FAQs about CSS placeholder text (FAQ)

How to change the color of placeholder text in CSS?

The color of placeholder text in CSS can be changed by using the ::placeholder pseudo-element. This pseudo-element allows you to style placeholder text in input or text area elements. Here is an example of how to change the color to red:

<input class="name-field" type="text" placeholder="Enter your name">

Remember that browser compatibility is important. For Firefox, use ::-moz-placeholder; for Internet Explorer, use :-ms-input-placeholder; for Chrome, Safari, and Opera, use ::-webkit-input-placeholder.

Can I change the font size of the placeholder text?

Yes, you can change the font size of the placeholder text. Just like changing the color, you can use the ::placeholder pseudo-element to change the font size. Here is an example:

.name-field {
  color: red;
}

This changes the font size of the placeholder text to 18px.

Is it possible to change the font style of placeholder text?

Absolutely, you can change the font style of the placeholder text. You can make it in italics, bold, or any other style you want. Here is an example of how to make it italic:

input[placeholder="Enter your name"] {
  color: red;
}

This changes the font style of the placeholder text to italics.

Can I change the opacity of the placeholder text?

Yes, you can change the opacity of the placeholder text. This can be done by using the opacity attribute in CSS. Here is an example:

::-webkit-input-placeholder {
  color: red;
}
:-moz-placeholder {/*Firefox 18-*/
  color: red;  
}
::-moz-placeholder {/*Firefox 19+*/
  color: red;  
}
:-ms-input-placeholder {  
  color: red;  
}

This changes the opacity of the placeholder text to 0.5, making it translucent.

How to add background color to placeholder text?

Unfortunately, you cannot add background color to the placeholder text. ::placeholder Pseudo-elements only allow you to set the color, font size, font style, and opacity of placeholder text. It does not support other attributes such as background-color.

Can I use CSS animation on placeholder text?

No, you cannot use CSS animation on placeholder text. ::placeholder Pseudo-elements do not support CSS animations or transitions.

Is it possible to set different placeholder styles in different ways?

Yes, you can set different placeholder styles in different ways. You just need to use a different class or ID for each input or text area element. Here is an example:

::-webkit-input-placeholder,
:-moz-placeholder,
::-moz-placeholder,
:-ms-input-placeholder {
  color: red;  
}

This will make the placeholder text in the input with class "input1" red, and the placeholder text in the input with class "input2" blue.

Can I use pseudo-classes with ::placeholder?

No, you cannot use pseudo-classes such as :hover, :active or :focus with ::placeholder. ::placeholder Pseudo-elements do not support pseudo-classes.

Is it possible to change the placeholder text using CSS?

No, you cannot change the placeholder text using CSS. The contents of placeholder text can only be changed using HTML.

Can I use media queries in ::placeholder?

Yes, you can use media queries in ::placeholder. This allows you to style the placeholder text in different ways depending on the screen size or device. Here is an example:

<input class="name-field" type="text" placeholder="Enter your name">

This changes the color of the placeholder text on the screen with a screen width of 600px or smaller to red.

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