title: CSS 3 date: 2020-12-25 20:22:47 background: bg-[#3473b5] tags: - web - css - style categories: - Programming intro: |
CSS is rich in capabilities and is more than simply laying out pages.
```html {.wrap}
#### Internal stylesheet
```html
<style>
body {
background-color: linen;
}
</style>
```html {.wrap}
Blue, 18-point text
### Add class
```html
<div class="classname"></div>
<div class="class1 ... classn"></div>
Support multiple classes on one element.
.post-title {
color: blue !important;
}
Overrides all previous styling rules.
h1 { }
#job-title { }
div.hero { }
div > p { }
See: Selectors
color: #2a2aff;
color: green;
color: rgb(34, 12, 64, 0.6);
color: hsla(30 100% 50% / 0.6);
See: Colors
background-color: blue;
background-image: url("nyan-cat.gif");
background-image: url("../image.png");
See: Backgrounds
.page-title {
font-weight: bold;
font-size: 30px;
font-family: "Courier New";
}
See: Fonts
.box {
position: relative;
top: 20px;
left: 20px;
}
See also: Position
animation: 300ms linear 0s infinite;
animation: bounce 300ms linear infinite;
See: Animation
/* This is a single line comment */
/* This is a
multi-line comment */
div {
display: flex;
justify-content: center;
}
div {
display: flex;
justify-content: flex-start;
}
See: Flexbox | Flex Tricks
#container {
display: grid;
grid: repeat(2, 60px) / auto-flow 80px;
}
#container > div {
background-color: #8ca0ff;
width: 50px;
height: 50px;
}
See: Grid Layout
counter-set: subsection;
counter-increment: subsection;
counter-reset: subsection 0;
:root {
--bg-color: brown;
}
element {
background-color: var(--bg-color);
}
See: Dynamic content
h1, h2 {
color: red;
}
h3.section-heading {
color: blue;
}
div[attribute="SomeValue"] {
background-color: red;
}
p:first-child {
font-weight: bold;
}
.box:empty {
background: lime;
height: 80px;
width: 80px;
}
* |
All elements |
div |
All div tags |
.classname |
All elements with class |
#idname |
Element with ID |
div,p |
All divs and paragraphs |
#idname * |
All elements inside #idname |
See also: Type / Class / ID / Universal selectors
Selector | Description |
---|---|
div.classname |
Div with certain classname |
div#idname |
Div with certain ID |
div p |
Paragraphs inside divs |
div > p |
All p tags one level deep in div |
div + p |
P tags immediately after div |
div ~ p |
P tags preceded by div |
See also: Adjacent / Sibling / Child selectors
a[target] |
With a |
a[target="_blank"] |
Open in new tab |
a[href^="/index"] |
Starts with |
[class|="chair"] |
Starts with |
[class*="chair"] |
containing |
[title~="chair"] |
Contains the word |
a[href$=".doc"] |
Ends with |
[type="button"] |
Specified type |
See also: Attribute selectors
a:link |
Link in normal state |
a:active |
Link in clicked state |
a:hover |
Link with mouse over it |
a:visited |
Visited link |
p::after |
Add content after p |
p::before |
Add content before p |
p::first-letter |
First letter in p |
p::first-line |
First line in p |
::selection |
Selected by user |
::placeholder |
Placeholder attribute |
:root |
Documents root element |
:target |
Highlight active anchor |
div:empty |
Element with no children |
p:lang(en) |
P with en language attribute |
:not(span) |
Element that's not a span |
input:checked |
Checked inputs |
input:disabled |
Disabled inputs |
input:enabled |
Enabled inputs |
input:focus |
Input has focus |
input:in-range |
Value in range |
input:out-of-range |
Input value out of range |
input:valid |
Input with valid value |
input:invalid |
Input with invalid value |
input:optional |
No required attribute |
input:required |
Input with required attribute |
input:read-only |
With readonly attribute |
input:read-write |
No readonly attribute |
input:indeterminate |
With indeterminate state |
p:first-child |
First child |
p:last-child |
Last child |
p:first-of-type |
First of some type |
p:last-of-type |
Last of some type |
p:nth-child(2) |
Second child of its parent |
p:nth-child(3n42) |
Nth-child (an + b) formula |
p:nth-last-child(2) |
Second child from behind |
p:nth-of-type(2) |
Second p of its parent |
p:nth-last-of-type(2) |
...from behind |
p:only-of-type |
Unique of its parent |
p:only-child |
Only child of its parent |
Property | Description |
---|---|
font-family: |
<font> |
font-size: |
<size> |
letter-spacing: |
<size> |
line-height: |
<number> |
| font-weight:
| <number> / bold / normal |
| font-style:
| italic / normal |
| text-decoration:
| underline / none |
| text-align:
| left / right
center / justify |
| text-transform:
| capitalize / uppercase / lowercase |
{.left-text}
See also: Font
style | weight | size (required) | line-height | family | ||
---|---|---|---|---|---|---|
font: |
italic |
400 |
14px |
/ |
1.5 |
sans-serif |
style | weight | size (required) | line-height | family (required) |
font-family: Arial, sans-serif;
font-size: 12pt;
letter-spacing: 0.02em;
/* Hello */
text-transform: capitalize;
/* HELLO */
text-transform: uppercase;
/* hello */
text-transform: lowercase;
@font-face {
font-family: 'Glegoo';
src: url('../Glegoo.woff');
}
color: red;
color: orange;
color: tan;
color: rebeccapurple;
color: #090;
color: #009900;
color: #090a;
color: #009900aa;
color: rgb(34, 12, 64, 0.6);
color: rgba(34, 12, 64, 0.6);
color: rgb(34 12 64 / 0.6);
color: rgba(34 12 64 / 0.3);
color: rgb(34.0 12 64 / 60%);
color: rgba(34.6 12 64 / 30%);
color: hsl(30, 100%, 50%, 0.6);
color: hsla(30, 100%, 50%, 0.6);
color: hsl(30 100% 50% / 0.6);
color: hsla(30 100% 50% / 0.6);
color: hsl(30.0 100% 50% / 60%);
color: hsla(30.2 100% 50% / 60%);
color: inherit;
color: initial;
color: unset;
color: transparent;
color: currentcolor; /* keyword */
Property | Description |
---|---|
background: |
(Shorthand) |
| background-color:
| See: Colors |
| background-image:
| url(...) |
| background-position:
| left/center/right
top/center/bottom |
| background-size:
| cover X Y |
| background-clip:
| border-box
padding-box
content-box |
| background-repeat:
| no-repeat
repeat-x
repeat-y |
| background-attachment:
| scroll/fixed/local |
{.left-text}
color | image | positionX | positionY | size | repeat | attachment | ||
---|---|---|---|---|---|---|---|---|
background: |
#ff0 |
url(a.jpg) |
left |
top |
/ |
100px auto |
no-repeat |
fixed; |
background: |
#abc |
url(b.png) |
center |
center |
/ |
cover |
repeat-x |
local; |
color | image | posX | posY | size | repeat | attach.. |
```css {.wrap} background: url(img_man.jpg) no-repeat center;
background: url(img_flwr.gif) right bottom no-repeat, url(paper.gif) left top repeat;
background: rgb(2,0,36); background: linear-gradient(90deg, rgba(2,0,36,1) 0%, rgba(13,232,230,1) 35%, rgba(0,212,255,1) 100%);
CSS The Box Model
------------
### Maximums/Minimums
```css
.column {
max-width: 200px;
width: 500px;
}
See also: max-width / min-width / max-height / min-height
.block-one {
margin: 20px;
padding: 10px;
}
.container {
box-sizing: border-box;
}
See also: Box-sizing
.invisible-elements {
visibility: hidden;
}
See also: Visibility
div {
margin: auto;
}
See also: Margin
.small-block {
overflow: scroll;
}
See also: Overflow
name | duration | timing-function | delay | count | direction | fill-mode | play-state | |
---|---|---|---|---|---|---|---|---|
animation: |
bounce |
300ms |
linear |
100ms |
infinite |
alternate-reverse |
both |
reverse |
name | duration | timing-function | delay | count | direction | fill-mode | play-state |
Property | Value |
---|---|
animation: |
(shorthand) |
animation-name: |
<name> |
animation-duration: |
<time>ms |
animation-timing-function: |
ease / linear / ease-in / ease-out / ease-in-out |
animation-delay: |
<time>ms |
animation-iteration-count: |
infinite / <number> |
animation-direction: |
normal / reverse / alternate / alternate-reverse |
animation-fill-mode: |
none / forwards / backwards / both / initial / inherit |
animation-play-state: |
normal / reverse / alternate / alternate-reverse |
{.left-text}
See also: Animation
/* @keyframes duration | timing-function | delay |
iteration-count | direction | fill-mode | play-state | name */
animation: 3s ease-in 1s 2 reverse both paused slidein;
/* @keyframes duration | timing-function | delay | name */
animation: 3s linear 1s slidein;
/* @keyframes duration | name */
animation: 3s slidein;
animation: 4s linear 0s infinite alternate move_eye;
animation: bounce 300ms linear 0s infinite normal;
animation: bounce 300ms linear infinite;
animation: bounce 300ms linear infinite alternate-reverse;
animation: bounce 300ms linear 2s infinite alternate-reverse forwards normal;
.one('webkitAnimationEnd oanimationend msAnimationEnd animationend')
.container {
display: flex;
}
.container > div {
flex: 1 1 auto;
}
.container {
display: flex;
display: inline-flex;
flex-direction: row; /* ltr - default */
flex-direction: row-reverse; /* rtl */
flex-direction: column; /* top-bottom */
flex-direction: column-reverse; /* bottom-top */
flex-wrap: nowrap; /* one-line */
flex-wrap: wrap; /* multi-line */
align-items: flex-start; /* vertical-align to top */
align-items: flex-end; /* vertical-align to bottom */
align-items: center; /* vertical-align to center */
align-items: stretch; /* same height on all (default) */
justify-content: flex-start; /* [xxx ] */
justify-content: center; /* [ xxx ] */
justify-content: flex-end; /* [ xxx] */
justify-content: space-between; /* [x x x] */
justify-content: space-around; /* [ x x x ] */
justify-content: space-evenly; /* [ x x x ] */
}
.container > div {
/* This: */
flex: 1 0 auto;
/* Is equivalent to this: */
flex-grow: 1;
flex-shrink: 0;
flex-basis: auto;
order: 1;
align-self: flex-start; /* left */
margin-left: auto; /* right */
}
.container {
display: flex;
}
.container > div {
width: 100px;
height: 100px;
margin: auto;
}
.container {
display: flex;
/* vertical */
align-items: center;
/* horizontal */
justify-content: center;
}
.container > .top {
order: 1;
}
.container > .bottom {
order: 2;
}
.container {
display: flex;
flex-direction: column;
}
.container > .top {
flex: 0 0 100px;
}
.container > .content {
flex: 1 0 auto;
}
A fixed-height top bar and a dynamic-height content area.
.container {
display: flex;
}
/* the 'px' values here are just suggested percentages */
.container > .checkbox { flex: 1 0 20px; }
.container > .subject { flex: 1 0 400px; }
.container > .date { flex: 1 0 120px; }
This creates columns that have different widths, but size accordingly according to the circumstances.
.container {
align-items: center;
}
Vertically-center all items.
.menu > .left { align-self: flex-start; }
.menu > .right { align-self: flex-end; }
#grid-container {
display: grid;
width: 100px;
grid-template-columns: 20px 20% 60%;
}
.grid {
display: grid;
width: 100px;
grid-template-columns: 1fr 60px 1fr;
}
/*The distance between rows is 20px*/
/*The distance between columns is 10px*/
#grid-container {
display: grid;
grid-gap: 20px 10px;
}
#grid-container {
display: block;
}
CSS syntax: - grid-row: grid-row-start / grid-row-end;
.item {
grid-row: 1 / span 2;
}
#grid-container {
display: inline-grid;
}
```css {.wrap} .grid { display: grid; grid-template-columns: 100px minmax(100px, 500px) 100px; }
### grid-row-start & grid-row-end
CSS syntax:
- grid-row-start: auto|row-line;<br>
- grid-row-end: auto|row-line|span n;
#### Example
```css
grid-row-start: 2;
grid-row-end: span 2;
grid-row-gap: length;
Any legal length value, like px or %. 0 is the default value
.item1 {
grid-area: 2 / 1 / span 2 / span 3;
}
#container {
display: grid;
justify-items: center;
grid-template-columns: 1fr;
grid-template-rows: 1fr 1fr 1fr;
grid-gap: 10px;
}
.item {
grid-area: nav;
}
.grid-container {
display: grid;
grid-template-areas:
'nav nav . .'
'nav nav . .';
}
#grid-container {
display: grid;
justify-items: start;
}
.grid-items {
justify-self: end;
}
The grid items are positioned to the right (end) of the row.
#container {
display: grid;
align-items: start;
grid-template-columns: 1fr;
grid-template-rows: 1fr 1fr 1fr;
grid-gap: 10px;
}
Define CSS Variable
:root {
--first-color: #16f;
--second-color: #ff7;
}
Variable Usage
#firstParagraph {
background-color: var(--first-color);
color: var(--second-color);
}
See also: CSS Variable
/* Set "my-counter" to 0 */
counter-set: my-counter;
/* Increment "my-counter" by 1 */
counter-increment: my-counter;
/* Decrement "my-counter" by 1 */
counter-increment: my-counter -1;
/* Reset "my-counter" to 0 */
counter-reset: my-counter;
See also: Counter set
body { counter-reset: section; }
h3::before {
counter-increment: section;
content: "Section." counter(section);
}
ol {
counter-reset: section;
list-marker-type: none;
}
li::before {
counter-increment: section;
content: counters(section, ".") " ";
}
html {
scroll-behavior: smooth;
}
Click me, the page will scroll smoothly to Getting started