Check out example codes for "media query". It will help you in understanding the concepts better.

Code Example 1

@media only screen and (max-width: 600px) {
  body {
    background-color: lightblue;
  }
}

Code Example 2

/* Extra small devices (phones, 600px and down) */
@media only screen and (max-width: 600px) {}

/* Small devices (portrait tablets and large phones, 600px and up) */
@media only screen and (min-width: 600px) {}

/* Medium devices (landscape tablets, 768px and up) */
@media only screen and (min-width: 768px) {}

/* Large devices (laptops/desktops, 992px and up) */
@media only screen and (min-width: 992px) {}

/* Extra large devices (large laptops and desktops, 1200px and up) */
@media only screen and (min-width: 1200px) {}

Code Example 3

// Example media query syntax
@media only screen and (min-width: 768px) {
  .my-example-class {
    padding: 50px;
  }
}

// Best Practice
// keep default style for smallest screen size (portrait mobile, below 576px)
// and then proceed in assending order with media query like below

// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) { ... }

// Medium devices (tablets, 768px and up)
@media (min-width: 768px) { ... }

// Large devices (desktops, 992px and up)
@media (min-width: 992px) { ... }

// so on ...

Code Example 4

@media only screen and (max-width: 600px) {
  .class {
    // Your CSS
  }
}

Code Example 5

@media (max-height : 800px){ /* from 0 to 800 px max height applies */
  p{
    font-size:10px
  }
}

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