Learn Responsive Design 
Learn responsive design techniques, like relative sizing units and media queries, to create websites viewable on devices of all sizes.
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Key Concepts
Review core concepts you need to learn to master this subject
CSS unit em
Usage of Percentages in CSS
background-size: cover;
CSS unit rem
Media Type in Media Queries
And Operator Media Queries
CSS Media Features in Media Queries
css media query
CSS unit em
CSS unit em
.nav-container {
font-size: 10px;
}
.nav-container span {
font-size: 1.5em; /* 10 x 1.5 = 15px */
}em is a CSS unit used to create relatively-sized content. 1 em unit represents the base font size of the current element.
In the example code block, <span> elements nested inside of elements with class nav-container will have a font size of 15px.
Sizing Elements
Lesson 1 of 2
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Learn Responsive Design
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