Revision as of 12:57, 7 April 2024

⭑HTML⭑

⊹A Simple HTML structure:

<body> = contains all elements that are visible

<head> = all the elements that are not visible on the page ex. <title> <style>

⊹General Technique: 1. Create element with HTML 2. Style with CSS one-by-one

⊹Well chosen content of H1 element is crucial to SEO.

⊹Only for links: <a href="https://www.w3schools.com" target="_blank">Visit Me!</a>

The target attribute specifies where to open the linked document.

Syntax: <a target="_blank|_self|_parent|_top|framename">

Entities

Help avoid rendering issues
Safeguard against more limited character encoding
Provide characters not available on a keyboard

Instead of	<	>	&
Use:	&lt ;	&gt ;	&amp ;

Use nbsp; HTML document ALWAYS appear together on 1 line

⊹Option + Command + I --- Google Chrome

Class

The class attribute can be used on any HTML element.

The HTML class attribute specifies one or more class names for an element.

Different HTML elements can point to the same class name.

JavaScript can access elements with a specific class name with the getElementsByClassName() method

Elements

Text elements

⊹ by default, come with margin at the top and bottom. So, {margin-top:0px; margin-bottom:0px; }

--- bold

--- underline

--- modify a specific part of the text without affecting the whole thing

.span-example {
  color: red
  margin-left: 12px; ---set a white space for text
}

.span-example:hover {
  text-decoration: underline;
}

<pre>

Text in a <pre> element is displayed in a fixed-width font, and the text preserves both spaces and line breaks. Really useful with ASCII-Art.

⊹<pre> elements with the default values:

pre {
 display: block;
 font-family: monospace;
 white-space: pre;
 margin: 1em 0;
}

<buttom>

Ex.

.button1 {
 background-color: blue;
 color: white;
 border: none;
 border-radius:18px;
 text-align: center;
 text-decoration: none;
 display: inline-block;
 font-weigh: bold;
 font-size: 16px;
 margin: 4px 2px;
 padding-bottom: 10px;
 vertical-align: top;
 transition-duration: 0.4s;
 cursor: pointer;
}

html: <button class="button button1">White</button>

{border-radius: 2px;} - rounded corner (ex. button )

{transition: background-color 1s, color 1s;}

{box-shadow:  5px(horizontal) 5px(vertical) 10px(blur) rgba(0, 0, 0, 0.6);}

"a" —> opacity, how see through this color is

Image and Text box

src - Specifies the path to the image

alt - Specifies an alternate text for the image

{
  width: 300px;
  height: 300px;
  object-fit: cover;
  object-position: contain;
  border-width: right;
  border-style: solid;
  border-color: red;

<input>

⭑CSS⭑

<link rel="stylesheet" href="style.css">

rel = relation

⊹Syntax simple CSS selectors

Element
class (define with .) -target
id (define with #)

⊹Combining Selectors:

Element with class selectors (selector.class)
Child (direct) selector (selector > selector)
Descendant selector (selector selector)

-Didn't cover:

Adjacent sibling selector (selector + selector)
General sibling selector (selector ~ selector)

⊹Pseudo-Class Selector (adds extra styles in a certain situation)

: link
: visited
: hover
: active
: nth-child

Ex.

.subscribe-button:hover {
Background-color: blue ;
opacity: 0.3 -> to fade out an element, 0 (transparent)
}

.subscribe-button:active {
Background-color: green;
}

{
trasition: opacity 1s;
}

⊹Conflict Resolution

Origin precedence: Last declaration wins
Inheritance: DOM Tree
Specificity: Most specific selector combination wins (has higher priority!)

(Score) 1. Style="..." 2. ID 3. Class, pseudo-class, attribute 4. # of Elements

Class name selector > Element name selector

⊹Text Styles

.style {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 24px;
  font-weight: bold;
  font-style: italic;
  text-align: center;
  color: #0000ff;
  line-height: 24px;
}

CSS Fonts

⭑Google Fonts put links into <head>, then change the font-family in CSS

Set Font Size With Em:

To allow users to resize the text (in the browser menu), many developers use em instead of pixels.

1em is equal to the current font size. The default text size in browsers is 16px. So, the default size of 1em is 16px.

The size can be calculated from pixels to em using this formula: pixels/16=em

⊹The Box Model

⊹The box-sizing property allows us to include the padding and border in an element's total width and height.

If you set box-sizing: border-box; on an element, padding and border are included in the width and height

* {
 box-sizing: border-box;
}

The * selector selects all elements.

The * selector can also select all elements inside another element.

Margin Collapse

Vertical(Top and bottom) margins that touch collapse and the larger one wins.

Horizontal margins combine together.

Margins don't define the width of the box. Just define how far other elements should be pushed away from it.

Space (around an element) = margin, Space (inside of an element) = Padding

⊹The float property is used for positioning and formatting content e.g. let an image float left to the text in a container.

float: left|right|none|inherit;

<style>
img {
 float: right;
}
</style>

Float don't have vertical margin collapse

⊹The clear property controls the flow next to floated elements.

Specifies what should happen with the element that is next to a floating element.

clear: none|left|right|both|initial|inherit;

img {
 float: left;
}
p.clear {
 clear: left;
}

⭑JAVA SCRIPT⭑

<script src="js/script.js"></script>
<script> </script>

User:Michel W/Self-learning: Difference between revisions