Font scaling based on the size of the container is a technique used to adjust the size of text within a container or element to make it more readable and visually appealing.

There are different approaches to achieving font scaling based on container size, but one common method is to use CSS (Cascading Style Sheets) and the vw (viewport width) unit. The vw unit is a relative unit of measurement that represents 1% of the viewport width.

To implement font scaling based on container size using CSS, you can set the font size of the text using the vw unit, and then adjust it with media queries at different breakpoints. For example:

/* Set the default font size to 3vw */
.container {
  font-size: 3vw;
}

/* Adjust font size for smaller screens */
@media (max-width: 768px) {
  .container {
    font-size: 5vw;
  }
}

/* Adjust font size for larger screens */
@media (min-width: 1200px) {
  .container {
    font-size: 2vw;
  }
}
In this example, the default font size for the .container element is set to 3% of the viewport width. At smaller screen sizes (up to 768px), the font size is increased to 5% of the viewport width, and at larger screen sizes (above 1200px), it is decreased to 2% of the viewport width.

This technique can be useful for responsive web design, as it allows the text to scale dynamically based on the size of the container or viewport, making it more readable and accessible on different devices and screen sizes.