css-notes/6. Fonts, Forms, and Pseudo Selectors/1. FONTS.md

# CSS - Typography, Icons

## Lesson Objectives

1. Explain how to load fonts into your website
1. Explain what a sprite sheet is and why we use it
1. Explain what an icon font is and what its advantages are
1. Explain what SVG stands for, what it is, and what its advantages are

## Explain how to load fonts into your website

1. Up until recently, fonts on the web were limited to what was installed on a computer
1. You could only depend on users having "System" fonts that were installed on every machine by default
1. Now you can load fonts into your website so each user doesn't have to install them manually

### Use a font-file

1. You or a designer can download or create actual font files and then reference them in your css files.
1. Good sites:
	- https://www.fontsquirrel.com/
	- http://www.myfonts.com/
	- https://typekit.com/

```css
@font-face {
	font-family: 'MyWebFont'; /* specify how you want the font to be referenced in the font-family property */
	src: url('fonts/Architects_Daughter/ArchitectsDaughter.ttf'); /* location of the font file */
}
html {
	font-family: 'MyWebFont'; /* call the web font */
}
```

### Use a link to a CSS file

1. Some font sites will give you the css file already, so you don't have to download the font files themselves
	- https://www.google.com/fonts

## Explain what a sprite sheet is and why we use it

### What and why

Most developers use sprite sheets instead of individual images for each of their icons.

1. Making many HTTP requests for many small files is slower than downloading and processing one large file.
1. Your browser will cache (save locally) the image
	- If you visit a different page with different icons from the same sprite sheet, the image is already available and loads from memory, not the server.

### How

1. Create a tag with `background-image:url()`, `background-position-x`, `background-position-y`, `width`, `height`;
1. use an `img` tag inside another tag with a specific `width`, `height`, `position:relative`, and `overflow: hidden;`.  Move the `img` around with `top`, `left`, and `position:absolute`

## Explain what an icon font is and what its advantages are

1. Sprite sheets have fixed size icons.  You can make the icons bigger, but they can end up looking pixelated
1. If you want the same icon in a different color (perhaps each page has a different color theme) you have to add a new image to the sprite sheet.
1. Icon fonts are just fonts, but instead of looking like letters, each "character" looks like an icon.

### http://fontello.com/

1. Using the font's characters
	1. Fontello goes one extra step by assigning icon shapes to unprintable characters in case you want to use that font for normal characters.
		1. Behind the scenes, traditional characters are stored as numbers.
		1. There are lots of other unusual characters that most developers never use (bells, weird whitespace characters, foreign characters).
		1. http://unicode-table.com/en/
	1. Go to the "Customize Codes" tab
	1. You'll see above the icon is a box
		- this represents an unprintable character
	1. Below the icon is the character's Unicode value (a four digit hexadecimal number)
	1. You can represent this character in two ways
		1. inside your HTML: `` (E800 is the 4 digit hex value)
		1. inside your CSS: `selector:after/before { content: '\E800' };`
			- you can insert content using CSS
	1. You could also change the character to be normal character
1. You can use their css and give your html classes

## Demonstrate how to make icons using SVG

1. Icon fonts can only be one color
1. SVG can be styled just like CSS

### Many ways to add SVG to your page

1. One external image
	- Can't restyle
	- Hover, etc doesn't work
	```css
		img {
			width: 200px;
			height: 200px;
		}
	```
	```html
	<img src="img.svg" />
	```
	```html
	<svg xmlns="http://www.w3.org/2000/svg">
		<style>
			#checkmark {
				fill: red;
			}
			#checkmark:hover {
				fill: blue;
			}
			circle {
				stroke: #006600;
				fill  : #00cc00;
			}
			circle:hover {
				stroke: darkblue;
				fill  : lightblue;
			}
		</style>
		<path id="checkmark" d="M27 4l-15 15-7-7-5 5 12 12 20-20z"></path>
		<circle cx="40" cy="40" r="24" />
	</svg>
	```

1. Write SVG directly into HTML

	```html
	<svg xmlns="http://www.w3.org/2000/svg">
		<path id="checkmark" d="M27 4l-15 15-7-7-5 5 12 12 20-20z"></path>
		<circle cx="40" cy="40" r="24" />
	</svg>
	```
	```css
	svg {
		width: 200px;
		height: 200px;
	}
	#checkmark {
	  fill: red;
	}
	#checkmark:hover {
	  fill: blue;
	}
	circle {
	  stroke: #006600;
	  fill  : #00cc00;
	}
	circle:hover {
	  stroke: darkblue;
	  fill  : lightblue;
	}
	```

1. External CSS/External image
	- Each differently styled element must be included and given id

	```html
	<svg>
		<use id="checkmark" xlink:href="img.svg#checkmark"></use>
		<use id="circle" xlink:href="img.svg#thecircle"></use>
	</svg>
	```
	```html
	<svg xmlns="http://www.w3.org/2000/svg">
		<path id="checkmark" d="M27 4l-15 15-7-7-5 5 12 12 20-20z"></path>
		<circle id="thecircle" cx="40" cy="40" r="24" />
	</svg>
	```
	```css
	svg {
		width: 200px;
		height: 200px;
	}
	#checkmark {
		fill: red;
	}
	#checkmark:hover {
		fill: blue;
	}
	#circle {
		stroke: #006600;
		fill  : #00cc00;
	}
	#circle:hover {
		stroke: darkblue;
		fill  : lightblue;
	}
	```