I have a scss file with over 20 lines of color variables. I want to create a css file with these variables to have one class for color and class for background-color.
Example:
from scss variable
$color-red: #FF0000;
to css
.color-red { color:#FF0000; }
.bg-color-red { background-color:#FF0000; }
Is there any Gulp plugin that allows me to do it?
any recomendation accepted but i need to do it with gulp if it is possible.
As #chriskirknielsen suggested, sass maps and the #each rule is a good choice here. This is the first time I have used these concepts but this works in my testing.
Your colors.scss file would look like this:
$colors: ("color-red": "#FF0000", "color-green": "#00ff40"); // etc.
#each $color, $value in $colors {
.#{$color} {
color: #{$value};
}
.bg-#{$color} {
background-color: #{$value};
}
}
The gulp-sass output in colors.css is:
.color-red {
color: #FF0000; }
.bg-color-red {
background-color: #FF0000; }
.color-green {
color: #00ff40; }
.bg-color-green {
background-color: #00ff40; }
See https://sass-lang.com/documentation/values/maps#do-something-for-every-pair
Related
I'm trying to use string interpolation on my variable to reference another variable:
// Set up variable and mixin
$foo-baz: 20px;
#mixin do-this($bar) {
width: $foo-#{$bar};
}
// Use mixin by passing 'baz' string as a param for use $foo-baz variable in the mixin
#include do-this('baz');
But when I do this, I get the following error:
Undefined variable: "$foo-".
Does Sass support PHP-style variable variables?
This is actually possible to do using SASS maps instead of variables. Here is a quick example:
Referencing dynamically:
$colors: (
blue: #007dc6,
blue-hover: #3da1e0
);
#mixin colorSet($colorName) {
color: map-get($colors, $colorName);
&:hover {
color: map-get($colors, #{$colorName}-hover);
}
}
a {
#include colorSet(blue);
}
Outputs as:
a { color:#007dc6 }
a:hover { color:#3da1e0 }
Creating dynamically:
#function addColorSet($colorName, $colorValue, $colorHoverValue: null) {
$colorHoverValue: if($colorHoverValue == null, darken( $colorValue, 10% ), $colorHoverValue);
$colors: map-merge($colors, (
$colorName: $colorValue,
#{$colorName}-hover: $colorHoverValue
));
#return $colors;
}
#each $color in blue, red {
#if not map-has-key($colors, $color) {
$colors: addColorSet($color, $color);
}
a {
&.#{$color} { #include colorSet($color); }
}
}
Outputs as:
a.blue { color: #007dc6; }
a.blue:hover { color: #3da1e0; }
a.red { color: red; }
a.red:hover { color: #cc0000; }
Sass does not allow variables to be created or accessed dynamically. However, you can use lists for similar behavior.
scss:
$list: 20px 30px 40px;
#mixin get-from-list($index) {
width: nth($list, $index);
}
$item-number: 2;
#smth {
#include get-from-list($item-number);
}
css generated:
#smth {
width: 30px;
}
http://sass-lang.com/docs/yardoc/file.SASS_REFERENCE.html#lists
http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#list-functions
Anytime I need to use a conditional value, I lean on functions. Here's a simple example.
$foo: 2em;
$bar: 1.5em;
#function foo-or-bar($value) {
#if $value == "foo" {
#return $foo;
}
#else {
#return $bar;
}
}
#mixin do-this($thing) {
width: foo-or-bar($thing);
}
Here's another option if you're working with rails, and possibly under other circumstances.
If you add .erb to the end of the file extension, Rails will process erb on the file before sending it to the SASS interpreter. This gives you a can chance to do what you want in Ruby.
For example: (File: foo.css.scss.erb)
// Set up variable and mixin
$foo-baz: 20px; // variable
<%
def do_this(bar)
"width: $foo-#{bar};"
end
%>
#target {
<%= do_this('baz') %>
}
Results in the following scss:
// Set up variable and mixin
$foo-baz: 20px; // variable
#target {
width: $foo-baz;
}
Which, of coarse, results in the following css:
#target {
width: 20px;
}
I came across the need to reference a colour dynamically recently.
I have a _colours.scss file for every project, where I define all my colours once and reference them as variables throughout.
In my _forms.scss file I wanted to setup button styles for each colour available. Usually a tedious task. This helped me to avoid having to write the same code for each different colour.
The only downside is that you have to list each colour name and value prior to writing the actual css.
// $red, $blue - variables defined in _colours.scss
$colours:
'red' $red,
'blue' $blue;
#each $name, $colour in $colours {
.button.has-#{$name}-background-color:hover {
background-color: lighten($colour, 15%);
}
}
I needed to use dynamic color values in sass variables.
After lots of search, I applied this solution:
In application.html.erb:
<style>
:root {
--primary-color: <%= current_client.header_color %>;
--body-color: <%= current_client.footer_color %>;
}
</style>
In variables.sass:
$primary: var(--primary-color);
And boom you are good to go!
Reference: https://medium.com/angular-in-depth/build-truly-dynamic-theme-with-css-variables-539516e95837
To make a dynamic variable is not possible in SASS as of now, since you will be adding/connecting another var that needs to be parsed once when you run the sass command.
As soon as the command runs, it will throw an error for Invalid CSS, since all your declared variables will follow hoisting.
Once run, you can't declare variables again on the fly
To know that I have understood this, kindly state if the following is correct:
you want to declare variables where the next part (word) is dynamic
something like
$list: 100 200 300;
#each $n in $list {
$font-$n: normal $n 12px/1 Arial;
}
// should result in something like
$font-100: normal 100 12px/1 Arial;
$font-200: normal 200 12px/1 Arial;
$font-300: normal 300 12px/1 Arial;
// So that we can use it as follows when needed
.span {
font: $font-200;
p {
font: $font-100
}
}
If this is what you want, I am afraid as of now, this is not allowed
I'm trying to use string interpolation on my variable to reference another variable:
// Set up variable and mixin
$foo-baz: 20px;
#mixin do-this($bar) {
width: $foo-#{$bar};
}
// Use mixin by passing 'baz' string as a param for use $foo-baz variable in the mixin
#include do-this('baz');
But when I do this, I get the following error:
Undefined variable: "$foo-".
Does Sass support PHP-style variable variables?
This is actually possible to do using SASS maps instead of variables. Here is a quick example:
Referencing dynamically:
$colors: (
blue: #007dc6,
blue-hover: #3da1e0
);
#mixin colorSet($colorName) {
color: map-get($colors, $colorName);
&:hover {
color: map-get($colors, #{$colorName}-hover);
}
}
a {
#include colorSet(blue);
}
Outputs as:
a { color:#007dc6 }
a:hover { color:#3da1e0 }
Creating dynamically:
#function addColorSet($colorName, $colorValue, $colorHoverValue: null) {
$colorHoverValue: if($colorHoverValue == null, darken( $colorValue, 10% ), $colorHoverValue);
$colors: map-merge($colors, (
$colorName: $colorValue,
#{$colorName}-hover: $colorHoverValue
));
#return $colors;
}
#each $color in blue, red {
#if not map-has-key($colors, $color) {
$colors: addColorSet($color, $color);
}
a {
&.#{$color} { #include colorSet($color); }
}
}
Outputs as:
a.blue { color: #007dc6; }
a.blue:hover { color: #3da1e0; }
a.red { color: red; }
a.red:hover { color: #cc0000; }
Sass does not allow variables to be created or accessed dynamically. However, you can use lists for similar behavior.
scss:
$list: 20px 30px 40px;
#mixin get-from-list($index) {
width: nth($list, $index);
}
$item-number: 2;
#smth {
#include get-from-list($item-number);
}
css generated:
#smth {
width: 30px;
}
http://sass-lang.com/docs/yardoc/file.SASS_REFERENCE.html#lists
http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#list-functions
Anytime I need to use a conditional value, I lean on functions. Here's a simple example.
$foo: 2em;
$bar: 1.5em;
#function foo-or-bar($value) {
#if $value == "foo" {
#return $foo;
}
#else {
#return $bar;
}
}
#mixin do-this($thing) {
width: foo-or-bar($thing);
}
Here's another option if you're working with rails, and possibly under other circumstances.
If you add .erb to the end of the file extension, Rails will process erb on the file before sending it to the SASS interpreter. This gives you a can chance to do what you want in Ruby.
For example: (File: foo.css.scss.erb)
// Set up variable and mixin
$foo-baz: 20px; // variable
<%
def do_this(bar)
"width: $foo-#{bar};"
end
%>
#target {
<%= do_this('baz') %>
}
Results in the following scss:
// Set up variable and mixin
$foo-baz: 20px; // variable
#target {
width: $foo-baz;
}
Which, of coarse, results in the following css:
#target {
width: 20px;
}
I came across the need to reference a colour dynamically recently.
I have a _colours.scss file for every project, where I define all my colours once and reference them as variables throughout.
In my _forms.scss file I wanted to setup button styles for each colour available. Usually a tedious task. This helped me to avoid having to write the same code for each different colour.
The only downside is that you have to list each colour name and value prior to writing the actual css.
// $red, $blue - variables defined in _colours.scss
$colours:
'red' $red,
'blue' $blue;
#each $name, $colour in $colours {
.button.has-#{$name}-background-color:hover {
background-color: lighten($colour, 15%);
}
}
I needed to use dynamic color values in sass variables.
After lots of search, I applied this solution:
In application.html.erb:
<style>
:root {
--primary-color: <%= current_client.header_color %>;
--body-color: <%= current_client.footer_color %>;
}
</style>
In variables.sass:
$primary: var(--primary-color);
And boom you are good to go!
Reference: https://medium.com/angular-in-depth/build-truly-dynamic-theme-with-css-variables-539516e95837
To make a dynamic variable is not possible in SASS as of now, since you will be adding/connecting another var that needs to be parsed once when you run the sass command.
As soon as the command runs, it will throw an error for Invalid CSS, since all your declared variables will follow hoisting.
Once run, you can't declare variables again on the fly
To know that I have understood this, kindly state if the following is correct:
you want to declare variables where the next part (word) is dynamic
something like
$list: 100 200 300;
#each $n in $list {
$font-$n: normal $n 12px/1 Arial;
}
// should result in something like
$font-100: normal 100 12px/1 Arial;
$font-200: normal 200 12px/1 Arial;
$font-300: normal 300 12px/1 Arial;
// So that we can use it as follows when needed
.span {
font: $font-200;
p {
font: $font-100
}
}
If this is what you want, I am afraid as of now, this is not allowed
I have an existing project with a scss file that uses semantic variables:
$background-color: white;
body {
background-color: $background-color;
}
I would like to change the background to black when I add a theming class to the body:
<body class="theme-dark">...</body>
and back to white if I remove the class (or switch to a theme-light).
I haven't found any light-weight methods to do this in scss (parametrizing a class for each theme seems like a very hard to maintain approach).
I've found a hybrid scss/css-custom properties solution:
original:
.theme-light {
--background-color: white;
}
update (based on Amar's answer):
:root {
--background-color: white;
}
.theme-dark {
--background-color: black;
}
$background-color: var(--background-color);
body {
background-color: $background-color;
}
Defining the scss variable as having a css-variable expansion as the value, i.e. (from above):
$background-color: var(--background-color);
generates the following css:
:root { --background-color: white; }
.theme-dark { --background-color: black; }
body { background-color: var(--background-color); }
which seems to be what we want...?
I like it since it only requires changing the definition of $background-color (not every usage in a very large scss file), but I'm unsure if this is a reasonable solution? I'm pretty new to scss, so maybe I've missed some feature..?
Doing this with SCSS is possible but you would have to add styles to all elements you want to theme. That is because SCSS is compiled at build-time and you can't toggle the variables with classes. An example would be:
$background-color-white: white;
$background-color-black: black;
body {
background-color: $background-color-white;
}
.something-else {
background-color: $background-color-white;
}
// Dark theme
body.theme-dark {
background-color: $background-color-black;
.something-else {
background-color: $background-color-black;
}
}
The best way to currently do it is by using CSS variables. You would define the default variables like this:
:root {
--background-color: white;
--text-color: black;
}
.theme-dark {
--background-color: black;
--text-color: white;
}
Then, you would use these variables in your elements like this:
body {
background-color: var(--background-color);
color: var(--text-color);
}
If the body element has the theme-dark class, it will use the variables defined for that class. Otherwise, it will use the default root variables.
All credit goes to Dmitry Borody
I would recommend an approach like what is mentioned in this Medium article. With this approach, you can assign what classes need to be themed without specifically mentioning the theme name so multiple themes can be applied at once.
First, you set up a SASS map containing your themes. The keys can be whatever makes sense to you, just make sure that each theme is using the same name for the same thing.
$themes: (
light: (
backgroundColor: #fff,
textColor: #408bbd,
buttonTextColor: #408bbd,
buttonTextTransform: none,
buttonTextHoverColor: #61b0e7,
buttonColor: #fff,
buttonBorder: 2px solid #fff,
),
dark: (
backgroundColor: #222,
textColor: #ddd,
buttonTextColor: #aaa,
buttonTextTransform: uppercase,
buttonTextHoverColor: #ddd,
buttonColor: #333,
buttonBorder: 1px solid #aaa,
),
);
Then use the mixin and function pair to add theme support.
body {
background-color: white;
#include themify {
background-color: theme( 'backgroundColor' );
}
}
.button {
background-color: lightgray;
color: black;
#include themify {
background-color: theme( 'buttonBackgrounColor' );
color: theme( 'buttonTextColor' );
}
&:focus,
&:hover {
background-color: gray;
#include themify {
background-color: theme( 'buttonBackgroundHoverColor' );
color: theme( 'buttonTextHoverColor' );
}
}
}
If you're going to be adding a lot of themes or a theme will be touching a lot of stuff, you might want to set up your SCSS files a little differently so that all the theming doesn't bloat your main CSS file (like the example above would do). One way to do this might be to create a themes.scss file and replicate any selector paths that need theming and have a second build script that outputs just the themes.scss file.
The Mixin
#mixin themify( $themes: $themes ) {
#each $theme, $map in $themes {
.theme-#{$theme} & {
$theme-map: () !global;
#each $key, $submap in $map {
$value: map-get(map-get($themes, $theme), '#{$key}');
$theme-map: map-merge($theme-map, ($key: $value)) !global;
}
#content;
$theme-map: null !global;
}
}
}
The Function
#function themed( $key ) {
#return map-get( $theme-map, $key );
}
in the Header of my HTML-Page i set the following CSS Variables:
:root{
--data-color-primary: #ffcc00;
--data-color-secondary: #4b4b4b;
}
In my SASS-File i use it as follow:
DIV.color {
&.color-primary {
background-color: var(--data-color-primary);
}
&.color-secondary {
background-color: var(--data-color-secondary);
}
}
Now i try to set the font-color depending on the brightness of the background-color:
#function set-notification-text-color($color) {
#if (lightness($color) > 60) {
#return #000000;
} #else {
#return #ffffff;
}
}
DIV.color{
&.color-primary {
background-color: var(--data-color-primary);
color: set-notification-text-color(var(--data-color-primary));
}
}
But in my SASS-compliler i get the following i get the following Error:
Error: argument $color of lightness($color) must be a color
How is ist possible to hand over der CSS variable to the function.
My Problem is, the CSS Variables are set in the Backend of my CMS by User (Liferay 7) an will be rendered in a *.FTL-File and is printed in the HTML-Code.
$primary: ${clr_primary};
$secondary: ${clr_primary};
and then i cant use the SASS-Variable $primary in my SASS-File.
Use SASS variables in your CSS variables.
$primary: #ffcc00;
$secondary: #4b4b4b;
:root{
--data-color-primary: #{$primary};
--data-color-secondary: #{$secondary};
}
Now call your mixin
DIV.color{
&.color-primary {
background-color: $primary;
color: set-notification-text-color($primary);
}
}
Another options would be to create a mixin which retrieves the CSS variable
#function color($color-name) {
#return var(--data-color-#{$color-name});
}
Now call that function like so
DIV.color {
&.color-primary {
background-color: color(primary);
color: set-notification-text-color(color(primary));
}
}
Check out this link for usefull information about combining CSS and SASS variables
https://codepen.io/jakealbaugh/post/css4-variables-and-sass
If you need to change CSS variables outside of :root you can do the following
.class {
// sass-lint:disable no-duplicate-properties
#{--background}: transparent;
#{--background-focused}: transparent;
// sass-lint:enable no-duplicate-properties
}
and this compiles to
.class {
--background: transparent;
--background-focused: transparent;
}
I am making a web app that is used in three (or more) different contexts, and I want each context to have a different color scheme. However, I don't want to have to maintain three different stylesheets when all that changes is colors, typically.
For instance, suppose the themes are red, blue, and orange. One of my stylesheets describes the link colors:
a {
color: $some_color;
}
I want to split this based on the class applied to the body:
body.style1 {
a {
color: $red;
}
}
body.style2 {
a {
color: $blue;
}
}
body.style3 {
a {
color: $orange;
}
}
You can see how this gets unwieldy pretty quickly if you're changing the style for lots of elements. Is there a way to do this more like this?
a {
&closest:body.style1 {
color: $red
}
&closest:body.style2 {
color: $blue;
}
&closest:body.style3 {
color: $orange;
}
}
This way I can code my scss in a clearer, more maintainable way.
It appers you don't have to have the & first, so this works (at least in 3.2.10):
a {
body.style1 & {
color: $red
}
body.style2 & {
color: $blue;
}
body.style3 &{
color: $orange;
}
}
This is what I prefer. Define a mixin like body-style :
#mixin body-style($style, $map) {
body.#{$style} & {
#each $property, $value in $map {
#{$property}: $value;
}
}
}
Then use this for every tag by passing $style as style class of body and $map as map of css keys and values.
a {
#include body-style(style1, (
color: red,
background: white
)
);
}
It will return :
body.style1 a {
color: red;
background: white;
}