I’ll make you a CSS Complete Cheat Sheet that’s easy to revise but still deep enough for real project use.
I’ll break it into sections with tables, diagrams, and examples so you can keep it as a ready reference.

📄 CSS Complete Cheat Sheet

1. CSS Basics

Feature	Description	Example
Full form	Cascading Style Sheets	—
Purpose	Controls look & layout of HTML elements	—
Syntax	`selector { property: value; }`	`p { color: red; }`

2. Types of CSS

Type	Where Applied	Example	Use Case
Inline	In `style` attribute of HTML tag	`<p style="color:red;">`	Quick test or single change
Internal	Inside `<style>` in `<head>`	`<style>p{color:red;}</style>`	Page-specific styles
External	Linked `.css` file	`<link rel="stylesheet" href="style.css">`	Large sites, reusability

3. CSS Selectors

Basic

p { color: red; }     /* Tag */
.myClass { color: red; } /* Class */
#myId { color: red; }    /* ID */

Combinators

div p { }    /* Descendant */
div > p { }  /* Direct child */
h1 + p { }   /* Adjacent sibling */
h1 ~ p { }   /* General sibling */

Attribute

input[type="text"] { }
a[href^="https"] { }
img[src$=".jpg"] { }

Pseudo-classes

a:hover { color: red; }
input:focus { border: 1px solid blue; }

Pseudo-elements

p::first-letter { font-size: 2em; }
p::after { content: "✓"; }

4. CSS Units

Type	Unit	Meaning
Absolute	`px`, `pt`, `cm`, `mm`, `in`	Fixed size
Relative	`%`	% of parent
	`em`	Relative to parent font-size
	`rem`	Relative to root font-size
	`vw`, `vh`	Relative to viewport width/height

5. Box Model

+-------------------------+
|       Margin            |
|  +-------------------+  |
|  |    Border         |  |
|  | +---------------+ |  |
|  | |  Padding      | |  |
|  | | +-----------+ | |  |
|  | | |  Content  | | |  |
|  | | +-----------+ | |  |
|  | +---------------+ |  |
|  +-------------------+  |
+-------------------------+

Properties:

margin: 10px;
padding: 20px;
border: 2px solid black;

6. Common CSS Properties

Text & Fonts

color: red;
font-family: Arial, sans-serif;
font-size: 16px;
font-weight: bold;
text-align: center;
text-decoration: underline;

Background

background-color: yellow;
background-image: url("bg.jpg");
background-repeat: no-repeat;
background-size: cover;

Borders

border: 2px solid black;
border-radius: 10px;

Layout

display: block | inline | flex | grid;
position: static | relative | absolute | fixed | sticky;
top: 10px; left: 20px;

7. Flexbox

Property	Purpose	Example
`display: flex;`	Enable flex	`display: flex;`
`justify-content`	Horizontal alignment	`center`, `space-between`
`align-items`	Vertical alignment	`center`, `flex-start`
`flex-wrap`	Wrap items	`wrap`, `nowrap`

8. Grid

display: grid;
grid-template-columns: repeat(3, 1fr);
grid-gap: 10px;

9. Animation & Transition

transition: all 0.3s ease;

@keyframes slide {
  from { transform: translateX(0); }
  to { transform: translateX(100px); }
}

div {
  animation: slide 2s infinite;
}

10. Responsive Design

@media (max-width: 768px) {
  body { font-size: 14px; }
}

11. Best Practices

Use external CSS for large projects
Use classes for styling instead of IDs
Group related properties together
Comment complex sections
Use CSS variables for consistent colors/fonts
Minify CSS for performance