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Implement various application scenarios of CSS::placeholder pseudo-element selector
Implement various application scenarios of CSS::placeholder pseudo-element selector
Nov 20, 2023 pm 03:17 PM
To implement multiple application scenarios of CSS::placeholder pseudo-element selector, specific code examples are required
In web development, CSS is a commonly used style sheet Language, used to control the layout and style of web pages. The ::placeholder pseudo-element selector is a new selector in CSS3, which is used to modify the placeholder style of input boxes (including text input boxes, password input boxes, etc.).
The following will introduce you to various application scenarios and provide corresponding code examples.
- Modify the color of the placeholder of the input box:
input::placeholder {
color: red;
}In the above code, change the color of the placeholder text of the input box to red.
- Modify the font size of the input box placeholder:
input::placeholder {
font-size: 16px;
}In the above code, change the font size of the input box placeholder to 16 pixels.
- Modify the font style of the placeholder of the input box:
input::placeholder {
font-family: 'Arial', sans-serif;
font-style: italic;
}In the above code, change the font style of the placeholder of the input box to Arial font, and use Shown in italics.
- Modify the background color of the input box placeholder:
input::placeholder {
background-color: yellow;
}In the above code, change the background color of the input box placeholder to yellow.
- Modify the transparency of the placeholder of the input box:
input::placeholder {
opacity: 0.5;
}In the above code, modify the transparency of the placeholder of the input box to 0.5, which is a semi-transparent state.
- Modify the alignment of the input box placeholder:
input::placeholder {
text-align: center;
}In the above code, center-align the placeholder text of the input box.
- Modify the border style of the input box placeholder:
input::placeholder {
border: 1px solid red;
}In the above code, add a red border to the input box placeholder.
- Modify the animation effect of the input box placeholder:
input::placeholder {
animation: placeholder 2s infinite;
}
@keyframes placeholder {
0% { opacity: 1; }
50% { opacity: 0.5; }
100% { opacity: 1; }
}In the above code, add a 2-second infinite loop animation to the input box placeholder Effect, giving it an opacity of 0.5 at 50%.
Through the above code examples, we can see various application scenarios of the ::placeholder pseudo-element selector. Developers can flexibly use these codes to implement customized input box placeholder styles according to specific needs.
It should be noted that since different browsers have different levels of support for the ::placeholder pseudo-element selector, if you want to ensure that the style can be displayed normally on all mainstream browsers, it is recommended to add browsing to the code. browser prefix, such as:
input::-webkit-input-placeholder {
/* Safari, Chrome, and Opera */
color: red;
}
input::-moz-placeholder {
/* Firefox 19+ */
color: red;
}
input::-ms-input-placeholder {
/* IE 10+ */
color: red;
}
input::-moz-placeholder {
/* Firefox 18- */
color: red;
}This can ensure that it can be displayed correctly on different browsers.
I hope the various application scenarios of the CSS ::placeholder pseudo-element selector introduced in this article can be helpful to you. If you have any questions, please leave a message for discussion.
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