@Media Max 768px

import javax.swing.*;  
public class FirstSwingExample {  
public static void main(String[] args) {  
JFrame f=new JFrame();//creating instance of JFrame  
          
JButton b=new JButton("click");//creating instance of JButton  
b.setBounds(130,100,100, 40);//x axis, y axis, width, height  
          
f.add(b);//adding button in JFrame  
          
f.setSize(400,500);//400 width and 500 height  
f.setLayout(null);//using no layout managers  
f.setVisible(true);//making the frame visible  
}  
}  

@media only screen and (max-width: 768px) {
  
}

	/* Pojo Accessibility */
	.pojo-a11y-toolbar-text {font-size: 15px !important; font-weight: 500 !important;}
	#pojo-a11y-toolbar {z-index: 99!important;}
	.br_alabel{ z-index:5!important; }
	#pojo-a11y-toolbar.pojo-a11y-toolbar-open .pojo-a11y-toolbar-toggle, #pojo-a11y-toolbar.pojo-a11y-toolbar-open .pojo-a11y-toolbar-overlay { 
		-webkit-box-shadow: 0 0 0px 0 rgb(0 0 0 / 20%); box-shadow: 0 0 0px 0 rgb(0 0 0 / 20%);}
	#pojo-a11y-toolbar.pojo-a11y-toolbar-left .pojo-a11y-toolbar-toggle { left: 200px; box-shadow: 1px 6px 24px 0 rgb(7 94 84 / 24%);}
	@media only screen and (max-width: 600px) {
  		#pojo-a11y-toolbar svg{height:18px; width:18px;}
		#pojo-a11y-toolbar.pojo-a11y-toolbar-left .pojo-a11y-toolbar-toggle {left: 180px;}
}

/^(0{0,2}\+?389[\s./-]?)(\(?[0]?[7-7][0-9]\)?[\s./-]?)([2-9]\d{2}[\s./-]?\d{3})$/gm

Multiplier
CSS custom properties are excellent when it comes to updating multiple elements at once. By injecting a --text-multiplier variable into the text elements' size, you can increase/decrease them all at a specific breakpoint by editing the variable.

// Method 3
h1 {
  font-size: calc(2em * var(--text-multiplier, 1));
}

p {
  font-size: calc(1em * var(--text-multiplier, 1));
}

@media (min-width: 48rem) {
  :root {
    --text-multiplier: 1.25;
  }
}

<style>
body {
  margin: 1em auto;
  max-width: 40em;
  width: 88%;
}
  
/* The CSS aspect-ratio property tells browsers to preserve a specific aspect ratio on an element when scaling the size of it up or down. */

iframe {
    width: 100%;
    height: 100%;
    aspect-ratio: 16 / 9;
}
</style>

<iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/_VDGysJGNoI" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

/*__Responsive Media Queries __*/

/* Mobile & Small devices */
@media only screen and (max-width: 480px) {...}

/* Portrait Tablets and Ipads devices) */
@media only screen and (max-width: 768px) {...}

/* Laptops and Small screens  */
@media only screen and (max-width: 1024px) {...}

/* Laptops, Desktops Large devices */
@media only screen and (max-width: 1280px) {...}

/* Extra large devices (large laptops and desktops) */
@media only screen and (min-width: 1281px) {...}