Datasets:
pre-view
/
CS50-raw

Dataset card Viewer Files Community
1
text
stringlengths
1
81
start
float64
0
10.1k
duration
float64
0
24.9
We're going to conventionally use dot scss to stand for this is a Sass file.
6,518.77
6.55
So here is now variables.scss.
6,525.32
3.26
And now what I can do in Sass is I can actually create variables
6,528.58
3.1
in the same way that we could create variables in a programming language,
6,531.68
3.05
like Python, which we'll soon see.
6,534.73
2.01
CSS normally doesn't support variables, but Sass
6,536.74
2.55
is going to give us that power.
6,539.29
1.86
In Sass, all variables begin with a dollar sign.
6,541.15
3.1
So I can create a variable $color to create a variable called color.
6,544.25
5.02
And I can say the variable called color is going to be equal to red.
6,549.27
4.33
So this line here, line 1, is my way of telling
6,553.6
2.52
Sass I'd like to create a variable called color
6,556.12
2.46
and I'd like for its value to be red.
6,558.58
3.45
And now, I can add the same styling I had before.
6,562.03
2.19
I can just use normal CSS and say for an unordered list
6,564.22
3.15
I'd like the font size to be 14 pixels.
6,567.37
2.61
But the color, instead of saying red here, I can use the name of a variable.
6,569.98
5.25
I can say $color to mean go ahead and use the value of the variable color
6,575.23
6.15
as the color for this unordered list.
6,581.38
2.97
Then for an ordered list, I'll also say font size 18 pixels
6,584.35
4.56
and say color should also be this variable called color.
6,588.91
4.77
By using a variable, I've removed the repetition.
6,593.68
2.85
Rather than having the word red show up in multiple places in my code
6,596.53
3.31
where I would need to change it twice if I ever needed to change it,
6,599.84
2.84
now I have defined the variable once.
6,602.68
2.25
And I only ever need to change it in one place
6,604.93
2.31
if I ever need to make modifications to this particular file.
6,607.24
4.09
So now, let's try and link this file.
6,611.33
3.41
We'll go back to variables.html.
6,614.74
2.58
Instead of putting the style code here, I'll go ahead and link a style sheet
6,617.32
7.21
and say, the href should be variables.scss,
6,624.53
3.66
because that's the file where my styling exists.
6,628.19
3.31
So now let me try and open up variables.html after I've linked
6,631.5
4.1
the CSS.
6,635.6
1.75
And, all right, something seems not quite right.
6,637.35
2.34
I specified font sizes.
6,639.69
1.44
I specified that everything should be red.
6,641.13
1.95
But it's not showing up.
6,643.08
1.05
Everything is showing up black.
6,644.13
1.69
And I don't see any of the differences in sizing.
6,645.82
3.41
And the reason for this is while the web browser, things like Chrome and Safari
6,649.23
4.41
and Firefox can understand CSS, they can't by default understand
6,653.64
4.71
SCSS, or Sass.
6,658.35
1.56
Sass is an extension to CSS that web browsers don't understand out
6,659.91
3.96
of the box.
6,663.87
1.48
So in order to solve this problem, once we've written our Sass file,
6,665.35
3.62
we need to compile it, convert it, translate it, so to speak,
6,668.97
3.45
from Sass into plain old CSS so that our browser is able to understand it.
6,672.42
5.83
And in order to do this, you'll need to install
6,678.25
2.3
a program called Sass on your computer.
6,680.55
1.97
And you can install it on Mac or PC or Linux.
6,682.52
2.53
And now, in the terminal, in order to do this compilation,
6,685.05
2.91
I'm going to say Sass variables.scss, the file I'd like to compile,
6,687.96
7.44
colon variables.css.
6,695.4
2.99
So variables.scss is the file that I would like to compile.
6,698.39
4.19
And the file I'd like to generate is variables.css.
6,702.58
3.44
I'd like to turn my Sass file into a plain old CSS file.
6,706.02
4.77
I'll go ahead and press Return.
6,710.79
1.71
And all right, that compilation process is now done.
6,712.5
3.02
And so now, inside of variables.html, instead of referencing the SCSS file,
6,715.52
6.94
I'm going to reference the CSS file as the style sheet,
6,722.46
3.36
because my web browser only understands CSS, it doesn't understand Sass.
6,725.82
5.69
Now, when I load the page, now I see the result I expect.
6,731.51
3.39
Everything shows up as red and the font sizes are different.
6,734.9
3.27
So ultimately, this was a 2-step process.
6,738.17
2.4
I first needed to take my Sass code, compile it into CSS.
6,740.57
4.29
And then I could link the CSS to this particular page.
6,744.86
3.75
But the advantage now is that if ever I want to make some sort of change,
6,748.61
3.3
I want to change the color, rather than change it in two places,
6,751.91
3.13
or you might imagine in a more complex page, like tens or dozens of places,
6,755.04
4.13
I just go to the SCSS file, and I change the color from red to blue.
6,759.17
6.45
Now, if I refresh the page, all right everything is still red.
6,765.62
3.35
And that's because I forgot a step.
6,768.97
1.7
I changed the Sass file.
6,770.67
1.84
But that doesn't automatically change the CSS file.
6,772.51
2.91
I need to now recompile the CSS file by saying Sass variables.scss
6,775.42
5.76
variables.css, to compile the file again using the updated Sass file.
6,781.18
5.58
And now, I see the updated changes.
6,786.76
3.09
And if you're curious as to what the updated file looks like,
6,789.85
2.55
I'm actually look at variables.css to see what code happens to be there,
6,792.4
4.47
and, though, it's styled a little bit strangely.
6,796.87
2.04
You can see that I have a UL with a font size a 14 and a color of blue.
6,798.91
4.17
So they've substituted the word blue for this variable.
6,803.08
2.97
And they've done the same thing for ordered lists as well.
6,806.05
4.07
Now, in practice, it's going to be pretty annoying
6,810.12
2.31
if I'm building a web page, building using Sass,
6,812.43
2.7
if I constantly need to go back and recompile my Sass into CSS
6,815.13
3.87
every single time.
6,819
1.14
What I'd like to do is just automate that process.
6,820.14
2.43
And Sass makes it easy to do this.
6,822.57
2.01
I can just say, Sass dash dash watch variables.scss variables.css.
6,824.58
7.19
And what that's going to do is now you see Sass is watching for changes.
6,831.77
3.88
Sass is going to monitor the variables.scss file.
6,835.65
3.9
And if ever I change my Sass file, Sass is going to know about it.
6,839.55
3.75
And it's automatically going to recompile the corresponding CSS file.
6,843.3
4.16
And you can do this not just with single files, but entire directories
6,847.46
2.92
as well if you have multiple different Sass files.
6,850.38
2.73
So now, what I can do is if in the variables.scss file I change
6,853.11
5.82
the color--
6,858.93
0.81
instead of blue, I now want it to be green, for example--
6,859.74
2.96