What Is REM and EM in CSS?
rem : a CSS unit which is relative to the font size of the html element. em : a CSS unit which is relative to the font size of the parent element.
What Is REM based on?
rem Unit. The rem unit, short for root em is a relative unit that’ll always be based upon the font-size value of the root element, which is the <html> element. And if the <html> element doesn’t have a specified font-size, the browser default of 16px is used.
What is VW in CSS?
Viewport Width (vw). This unit is based on the width of the viewport. A value of 1vw is equal to 1% of the viewport width. Viewport Minimum (vmin). This unit is based on the smaller dimension of the viewport.
Should I use em or REM?
Use em units for sizing that should scale depending on the font size of an element other than the root. Use rem units for sizing that doesn’t need em units, and that should scale depending on browser font size settings. Use rem units unless you’re sure you need em units, including on font sizes.
How do I use REM in CSS?
To start with, we set 16px as the font size on the <html> element.
- To recap, the em unit means “my parent element’s font-size” in the case of typography. …
- To recap, the rem unit means “The root element’s font-size”. …
- Try changing the width of the wrapper or the percentage value to see how this works.
What does the word REM mean?
rapid eye movement
What Is REM bootstrap?
New Unit (rems) for Typography
Typography font sizing in Bootstrap 4 is done completely based on the rem unit of measurement. It’s actually a super easy concept to grasp. With rem , all font sizes are relative to the root element (aka, the html tag).
How much is a rem?
A rem is equal to 0.01 sievert in the International System of Units (SI).
What is justify content in CSS?
The CSS justify-content property defines how the browser distributes space between and around content items along the main-axis of a flex container, and the inline axis of a grid container.
How do you use VW CSS?
To use vh and vw values, just type “Nvh” or “Nvw” (where “N” represents the percentage of the viewport you’d like to cover) into any width or height field. So to cover 100% of the viewport, you’d set 100% for the width and 100vh for the height. To cover half of the viewport height, you’d set a height of 50vh.
What is flex in HTML?
A flex container expands items to fill available free space or shrinks them to prevent overflow. Most importantly, the flexbox layout is direction-agnostic as opposed to the regular layouts (block which is vertically-based and inline which is horizontally-based).
What is difference between PX and REM in CSS?
When user sets different font-size on browser, REM automatically scale up and down elements like fonts, images etc on the webpage which is not the case with PX. In the below gif left side text is set using font size REM unit while right side font is set by PX unit.