45 CSS Reference

Here are some quick reference reminders about the features of CSS introduced in this book. Links to further details are provided. For full details, I recommend w3schools.

Quick Facts

• CSS (Cascading Style Sheets) define how the document should look.
• You should maintain a strict separation of concerns between HTML and CSS.
• CSS is not a programming language.

CSS Stylesheets

<style> internal stylesheet </style>
<link rel="stylesheet" href="external stylesheet url">
<html_tag style="inline styles">

The CSS Cascade

1. External Stylesheets First
2. Then Internal Stylesheets
3. Then Inline Styles
4. More Specific Beats Less Specific

CSS Syntax

selector {
    property: value;
    property: value;
    ...
}

CSS Selectors

tag_name {...}
.
.class {...}
selector.class {...}
.
#id {...}
.
selector1, selector2, ... {...}
.
parent child {...}
.
[attribute=value] {...} 
.
selector:hover {...} 
selector:active {...}
.
More Selectors

CSS Basic Properties

color (HTML Colors)
.
background-color (HTML Colors)
background-image (url("url"))
.
font-family (serif, sans-serif, cursive, fantasy, monospace, etc.)
font-size (10px, 24px, etc.)
font-weight (bold, normal, etc.)
font-variant (small-caps, etc.)
.
text-decoration (underline, none, etc.)
text-align (center, left, right, justify)
.
list-tyle-type (square, circle, disc, decimal, none, etc.)
.
float: left, right
.
List of all CSS properties

CSS Box Model Properties

See diagram at right. Each property can be set with px or % units. You can set top, bottom, left, and right separately (e.g., padding-left).

Here are some more useful properties:

box-sizing: border-box;

max-width (px or %);
margin: auto;

width: auto;

border-width (px)
border-style(solid, dashed, etc.)
border-color (HTML Colors)
border: width style color;
border-radius (px)

CSS Flexbox

display (flex, block, inline, none)
flex-direction (row, column)
justify-content (space-between, etc)
.
box-sizing: border-box; 

Set % widths on all images and divs within a flexbox
.
More info here on flexboxes

CSS Media Queries

@media (max-width: ___px) {
    /* CSS Rules go Here */
}

@media (min-width: ___px) {
    /* CSS Rules go Here */
}

@media (min-width: ___px) and (max-width: ___px) {
    /* CSS Rules go Here */
}

@media print {
    /* CSS Rules go Here */
}

Use CSS display property (flex, block, inline, none) to show or hide elements.

CSS Reset Rule

* {
    padding: 0;
    margin: 0;
    ...
}

CSS Table Styling

table { 
    border-collapse: collapse;
    /* prevents extra space around th and td elements */
}

tbody tr:nth-child(even) {
    /* styles every other tr inside the tbody
       can also use nth-child(odd) */
}