CSS Houdini library.
<script src="https://cdn.jsdelivr.net/gh/jerosoler/cornerbox/CornerBox.js"></script>
npm install cornerbox
Download Cornerbox.js
file.
if ('paintWorklet' in CSS && 'registerProperty' in CSS && 'CSSUnitValue' in window) {
CSS.registerProperty({
name: '--cornerbox-width',
syntax: '<length>',
initialValue: '10px',
inherits: false
});
CSS.registerProperty({
name: '--cornerbox-length',
syntax: '<length>',
initialValue: '10px',
inherits: false
});
CSS.registerProperty({
name: '--cornerbox-color',
syntax: '<color>',
initialValue: '#ffffff',
inherits: false
});
CSS.paintWorklet.addModule('CornerBox.js');
} else {
console.log("Not Supported");
alert("Not Supported");
}
div {
--cornerbox-color:#1100fc;
--cornerbox-width: 5px;
--cornerbox-length: 15px;
background-image: paint(cornerbox);
}