Variable declaration with $ in SASS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the $ symbol represent in Sass?

In Sass, the $ symbol is used to declare a variable. It helps store values like colors, sizes, or fonts that you can reuse throughout your stylesheet.

beginner

How do you declare a variable named $main-color with the value #3498db in Sass?

You write:

$main-color: #3498db;

This sets $main-color to a blue color you can use later.

beginner

Why use variables in Sass instead of repeating values?

Variables make your code easier to update and maintain. Change the value once, and it updates everywhere the variable is used, saving time and reducing mistakes.

intermediate

Can you change the value of a Sass variable after it is declared?

Yes, Sass variables can be reassigned later in the same scope, and the new value will be used in subsequent rules.

beginner

How do you use a Sass variable inside a CSS rule?

Use the variable by writing its name with $. For example:

color: $main-color;

This applies the stored color value.

What symbol starts a variable name in Sass?

A %

B #

C @

D $

In Sass, variables always start with the $ symbol.

Which of these is a correct Sass variable declaration?

A $font-size: 16px;

B font-size = 16px;

C @font-size: 16px;

D font-size: $16px;

Sass variables are declared with $name: value; syntax.

If you want to change a color used many times, what is the best Sass practice?

A Change each color manually

B Use a variable and change its value once

C Use inline styles

D Use !important everywhere

Using variables lets you update the color in one place, which updates all uses.

Can you reassign a Sass variable after it is set?

A Yes, anytime

B Only if you use !default

C Only inside media queries

D No, variables are immutable

Sass variables can be reassigned after they are declared.

How do you apply a Sass variable $main-color to a CSS property?

A color: main-color;

B color: #main-color;

C color: $main-color;

D color: var(main-color);

Use the variable name with $ directly in the property value.

Explain how to declare and use a variable in Sass with an example.

Think about how you store a color once and use it multiple times.

Why are variables helpful in Sass? Describe a real-life situation where they save time.

Imagine changing a color on a website with many pages.

Practice

1. What symbol is used to declare a variable in Sass?

easy

A. $

B. #

C. @

D. %

Solution

1. Step 1: Recall Sass variable syntax

   In Sass, variables always start with the $ symbol to distinguish them from other values.

2. Step 2: Identify the correct symbol

   Among the options, only $ is used for variables in Sass.

3. Final Answer:

   $ -> Option A

4. Quick Check:

   Variables start with $ in Sass [OK]

Hint: Remember: Sass variables always begin with $ [OK]

Common Mistakes:

• Using # or @ instead of $ for variables
• Confusing CSS IDs (#) with Sass variables
• Omitting the $ symbol before variable names

2. Which of the following is the correct way to declare a color variable in Sass?

easy

A. main-color: $3498db;

B. $main-color: #3498db;

C. $main-color = #3498db;

D. @main-color: #3498db;

Solution

1. Step 1: Check variable declaration syntax

   Sass variables start with $, followed by the name, a colon, then the value, ending with a semicolon.

2. Step 2: Compare options

   $main-color: #3498db; matches the correct syntax: $main-color: #3498db;. Others use wrong symbols or order.

3. Final Answer:

   $main-color: #3498db; -> Option B

4. Quick Check:

   Variable declaration uses $name: value; [OK]

Hint: Use $name: value; to declare variables in Sass [OK]

Common Mistakes:

• Using = instead of : to assign values
• Placing $ after the variable name
• Using @ instead of $ for variables

3. What will be the background color of the button in this Sass code?

$btn-bg: #ff0000;
button {
  background-color: $btn-bg;
}

medium

A. Blue

B. Green

C. Red

D. No color (default)

Solution

1. Step 1: Identify the variable value

   The variable $btn-bg is assigned the color #ff0000, which is red.

2. Step 2: Check usage in button style

   The button's background-color uses $btn-bg, so it will be red.

3. Final Answer:

   Red -> Option C

4. Quick Check:

   $btn-bg = #ff0000 (red) [OK]

Hint: Match variable value to color code to find output [OK]

Common Mistakes:

• Confusing hex color codes with color names
• Forgetting to use $ before variable name
• Assuming default color if variable is used

4. Identify the error in this Sass variable declaration:

$font-size 16px;

medium

A. Variable name should not start with $

B. Semicolon is missing at the end

C. Value should be in quotes

D. Missing colon between variable name and value

Solution

1. Step 1: Review correct variable syntax

   Sass variables require a colon : between the name and value, like $font-size: 16px;.

2. Step 2: Identify missing colon

   The code misses the colon, causing a syntax error.

3. Final Answer:

   Missing colon between variable name and value -> Option D

4. Quick Check:

   Variable declaration needs colon : [OK]

Hint: Check for colon : after variable name [OK]

Common Mistakes:

• Omitting colon between name and value
• Using = instead of :
• Forgetting semicolon at end (less critical)

5. You want to create a Sass variable for spacing that changes based on screen size. Which is the best way to declare and use it?

$spacing: 1rem;

@media (min-width: 600px) {
  $spacing: 2rem;
}

.container {
  padding: $spacing;
}

hard

A. Variables cannot be redefined inside media queries

B. This works; $spacing changes inside media query

C. Use !default to change variable inside media query

D. Declare two variables and use @if to switch

Solution

1. Step 1: Understand Sass variable scope

   Sass variables are static and cannot change inside media queries because media queries are CSS rules, not Sass logic blocks.

2. Step 2: Evaluate the code behavior

   Redefining $spacing inside @media does not work; Sass processes variables before CSS is generated.

3. Step 3: Correct approach

   To handle responsive spacing, declare separate variables or use mixins/functions with media queries.

4. Final Answer:

   Variables cannot be redefined inside media queries -> Option A

5. Quick Check:

   Sass variables are static, not dynamic in media queries [OK]

Hint: Sass variables are static; media queries can't change them [OK]

Common Mistakes:

• Trying to redefine variables inside media queries
• Assuming Sass variables behave like CSS custom properties
• Not using separate variables or mixins for responsiveness