CSS Selectors MasterClass | Sigma Web Development Course - Tutorial #17
Summary
TLDRThis video script delves into the fundamentals of CSS selectors, essential for applying styles to web elements. It covers element, class, and ID selectors, explaining how they target specific elements or groups. The instructor also introduces child, descendant, and universal selectors, emphasizing their importance in web development. Furthermore, pseudo-selectors are explored, demonstrating how they alter styles based on user interactions like hovering or visiting links. The script promises to build on these concepts in future lessons, aiming to transition to real-world web app development.
Takeaways
- đ CSS selectors are used to select HTML elements to which styles will be applied.
- đ You can select elements by their ID, class, element name, or by their relationship to other elements.
- đš The video emphasizes the importance of understanding selectors for efficient CSS styling.
- đ The instructor demonstrates creating a new HTML file and applying internal CSS for direct visibility of changes.
- đ„ Element selectors are basic and apply styles to all elements of a certain type, which can have drawbacks if specificity is needed.
- đČ Class selectors allow for styling specific elements by assigning a class name, offering more targeted styling.
- đŻ ID selectors are used to target a single element with a unique ID, ensuring that styles are applied only to that element.
- đ¶ Child selectors apply styles to direct children of a specified element, not to all descendants.
- đ Descendant selectors style any element that is a descendant of a specified element, regardless of its depth in the hierarchy.
- đ Universal selectors apply styles to all elements on the page, such as setting default margin and padding to zero.
- đ Pseudo-selectors add interactivity, such as styling links on different states (visited, active, hover) and targeting first child elements.
- đ The script suggests further research on pseudo-classes for a deeper understanding, with additional resources provided in the description or pinned comments.
Q & A
What are CSS selectors used for?
-CSS selectors are used to select HTML elements to which styles will be applied.
How can you select an element by its name in CSS?
-You can select an element by its name using the element selector, which targets all elements of that type.
What is the purpose of using an ID selector in CSS?
-The ID selector is used to target a specific element with a unique ID, allowing you to apply styles to that one element.
Can you explain the concept of a class selector in CSS?
-A class selector in CSS is used to apply styles to multiple elements that share the same class attribute.
What is the drawback of using an element selector for styling?
-The drawback of using an element selector is that it will apply the style to all elements of that type, which might not be the desired effect if you only want to target specific elements.
How does a child selector work in CSS?
-A child selector in CSS targets elements that are direct children of a specified parent element, allowing for more specific styling rules.
What is a descendant selector and how is it different from a child selector?
-A descendant selector targets elements that are descendants of a specified element, regardless of their depth in the hierarchy. It is different from a child selector, which only targets direct children.
What is the universal selector in CSS and what does it do?
-The universal selector in CSS is denoted by an asterisk (*) and it targets all elements within the scope of the stylesheet, allowing you to apply styles to every element.
Can you describe what a pseudo selector is in CSS?
-A pseudo selector in CSS is used to define a special state of an element, such as `:hover`, `:active`, `:first-child`, etc., allowing you to apply styles based on those states.
How does the ':first-child' pseudo selector work?
-The ':first-child' pseudo selector targets elements that are the first child within their parent element, allowing you to apply styles specifically to those elements.
What is the purpose of the ':hover' pseudo selector in CSS?
-The ':hover' pseudo selector is used to apply styles to an element when the user's mouse pointer hovers over it, providing a visual feedback to the user.
Outlines
đ Introduction to CSS Selectors
This paragraph introduces the concept of CSS selectors, which are used to apply styles to specific elements on a webpage. The instructor discusses various types of selectors, including element, class, and ID selectors, and explains how they can be used to target elements for styling. The video emphasizes the importance of understanding selectors for efficient web development. The instructor also encourages viewers to engage by commenting and provides a brief demonstration of applying a background color to a div element using an element selector.
đš Exploring Advanced CSS Selectors
The second paragraph delves into more advanced CSS selectors, such as child and descendant selectors, which allow for more precise control over styling based on the relationship between elements. The instructor provides examples of how to style direct children of a div or any paragraph that is a descendant of a div. Additionally, the paragraph covers the universal selector for resetting margins and paddings, and introduces pseudo-selectors for links, demonstrating how to change styles based on the link's state, such as 'visited' or 'hover'.
đ Understanding Pseudo-Selectors and Their Applications
In the final paragraph, the focus is on pseudo-selectors, which are used to define the style of an element in a specific state. The instructor explains 'active', 'hover', and 'first-child' pseudo-selectors with examples, showing how they can be used to change the appearance of links or elements when interacted with or based on their position in the document structure. The paragraph concludes with an invitation for viewers to explore additional resources on selectors and pseudo-classes, and a reminder of the upcoming projects and the need to build practical skills for web development.
Mindmap
Keywords
đĄSelectors
đĄElement Selector
đĄClass Selector
đĄID Selector
đĄChild Selector
đĄDescendant Selector
đĄUniversal Selector
đĄPseudo Selectors
đĄPseudo Class
đĄCSS Comments
đĄInternal CSS
Highlights
Selectors in CSS are used to select an element to apply styles.
Styles can be applied to elements with an ID, class, or by their name.
Specific styling can be applied based on the type of element within another element.
The importance of understanding CSS selectors for ease of web development.
Introduction to element selectors and their basic usage.
Drawbacks of element selectors when additional elements are added.
Class selectors allow styling specific elements with the same class attribute.
ID selectors target elements with a unique ID for specific styling.
Child selectors apply styles to direct children within a specified element.
Descendant selectors style elements that are descendants of a specified element.
Universal selector resets margin and padding for all elements.
Pseudo selectors modify styles based on user actions or element states.
Explanation of the :visited pseudo selector for styling visited links.
Demonstration of :hover pseudo selector changing styles on mouseover.
Active pseudo selector changes styles during the active click state of a link.
First-child pseudo selector styles the first child element within a parent.
The rarity of using first-child pseudo selector in web development.
Encouragement to focus on main selectors for the majority of web development tasks.
Upcoming videos will cover more selectors and their practical applications.
Invitation to engage with the course by bookmarking, accessing the playlist, and following along with the source code.
Transcripts
Guys, we talked about selectors in CSS and we said that selectors are used to select an element on which style is going to be applied.
Now, what kind of elements can we apply style on and how can we select those elements?
For example, element with an id, element with a class, we can target the element by its name.
And we can also decide that if there is a particular type of element in a particular type of element, then only the styling is applied.
I will explain the rules of applying this styling in this video and explain the selectors to you.
If you are enjoying this course, then write sigma patch opi in the comment below.
We have to maintain high energy throughout the course.
I want to give you a heads up that this video is very important.
This is a very important video of CSS.
So increase your excitement.
Let's go to the computer screen.
Let's roll the intro.
Intro
Intro
Intro
Intro
Alright guys, so I have come to my computer screen.
And the first thing I am going to do is
to make a folder of video 17.
And video 17 is one of the most important video of css
because if you understand how the selector works
then your work will be very easy
so I will make video 17 here
index.html will be made here
and I am going to use internal css here
I will not make it in stylesheet
so that you can see what I am doing
And here I will do a lot of things
I will do word wrap, screen cast mode
So that you can see whatever button I press
And I will write css selectors
And I will make a div here
I am a div
If you have not accessed it yet, do play the playlist of sigma web development
And the source code is getting updated
So you don't have to worry about it
Now what i am going to do
I will do a simple thing, i will preview it first
And i want to make the background of this div red
Now you will ask why do you want to make the background of this div red
Because i want to know how much space this div is taking
That's why I want to make it red
So I will simply give the background red
So I will first put a style tag here
I will say that the div
Make the background color red
Now this is our property and value
I will tell you more about property and value
but for now you understand this is property and value
so what I did here was element selector
so I will write here element selector
and I will comment it here
in CSS comments are written like this
here forward slash star and star forward, whatever we write in between,
Those are the comments in CSS. So I have put a CSS comment
That this is an element selector, you will see here.
So the background of this is red.
This was our element selector.
A very basic selector.
Now the element selector that I have made here,
What are its drawbacks?
The moment I add another div here,
So what will happen?
The background of this background will also turn red
and it is possible that you don't want to
make this div's background red
so if you don't want to make this div's background red
then what will you do? definitely you will
use some other type of selector
and you will want to use a specific selector
so I can say that do one thing, where class is red
only make that div red, only that div
should be red, so i have made
class is equal to red
and because i have made class is equal to red
you can see here
if i write
.red and after
.red if i make background
color red, let's say i
comment this, i don't want all div
to be red, so i show don't want all div to be red.
So I'll show you that only this div will be red.
So here I used class selector.
So this is our class selector.
I'll write class selector.
Next one is id selector.
You might have guessed it as soon as you heard ID selector
let us say I want the hashtag red ID
or let's do one thing
let's make an ID with hashtag green
and if I write background color green
then wherever I will give ID green it will be green
you can see here I am another div
it doesn't have any color, background color but as soon as I give it ID green, I will show you
I will write here
one minute, I will give it ID
green and you can see that in green name
I have given background color green
its background color will be green
so this is our ID selector
it was very simple, right?
yes, it is simple
we make things simple here, okay
now I will tell you what is child selector
and the source code
this will work for notes
so what is child selector, if i want
paragraph in div to be blue
so i say the color of paragraph in div
should be blue and background color should be
background color should be let's say background color should be brown
let's say I want this
if I put a paragraph in any div
I am a para inside div
so what will happen? this selector will be applied
child selector
because this is a child of div
and I have said that if any paragraph of div is child
then what will happen?
then its background will be brown and
color will be blue. As simple as that.
Now i will show you one thing. If i wrap this whole thing in div
understand this carefully. Actually i will span this
not div. I will
put it in main or any other element
Let's say I use article tag here
So now this paragraph is not in div, now it is in article
So this property will not be applied, I will show you
Now this property is not applied
Because this selector means that if it is directly in div
Direct child, then this selector will be applied or not Means if div has a direct child Then
This selector will be applied
Here it's not a direct child
It's an article and then p
But if i want
If paragraph is a descendant of any div
Then this property will be applied
Then i have another way
i will simply
use descendant selector
and what is descendant selector
we write it like this
i will write div, space and p
i am saying that div should have p
no matter what it is I'll write case and then p I'm saying p should be in div
whether it's in article, main, footer
it should be in div
it should be a descendant of div
so you can see that it's applied
but when i talk about child selector
it should be direct child
i hope you are getting the sense
Now there is universal selector
Means i want to give margin to all elements
0 and padding 0
I will write p0
Means all elements have margin 0 and padding 0
See everything is stuck here
Earlier margin and padding 0 see all are stuck here before margin and padding was there
by default
but now margin and padding is gone
like you saw
i hope you understood
now see there are many types of selectors
but these are the most used selectors
now i will tell you about more selectors
in the coming videos
but these are the ones with which we will do web development
so i don't want to confuse you more
And you guys
Didn't learn the main selectors
So I want you to focus on this
This is the most important
Through this, 95 or 99%
Of the websites are made, so let's focus on this
For now, I hope
You guys understood this
And you guys understood it very well
There is one more selector which is also important
And that is pseudo selectors
Now what is this pseudo selector?
I have a link, I will write
Universal selector
Universal selector
Universal selector
Why is there no comment ok, universal selector, what is this? why comment is not working, ok it is working
now here what I will do, I will write
Pseudo, Pseudo, yes I know it is called pseudo, don't write in the comment
that it is not Pseudo, it is pseudo
it is not pneumonia, it is pneumonia
I know P is silent here, so why did you put silent
tell me in the comment section, when it was silent, let it be like this I know that P is silent So why did you put it?
Tell me in the comment section
Tell me in the comment section
But now i will share my knowledge with you
And that is pseudo selectors
Now assume i have a link
Now i will write
Https://www.google.com
and i'll write go to google
and
it's very good, you'll go to google
and you'll see what's new in it
let's say it's color is white
no not white, let's say it's color is yellow
so i want a visited
a visited
what should be its color? yellow
so i make its color yellow
so will it be yellow? yes
so anchor tags, if i want to see yellow color after visit
so i can use pseudo selector
so here you can see yellow color then you can use pseudo selector so here you can see
the color changing, after this if you
link a colon, means that link which
is not visited, and suppose you want the color to be green
so any link i will put, what will be the color
suppose i will do it like this
go to facebook, and yes
let's capitalize google's g, so will it be I will go to facebook ok and yes we will capitalise google
so will it be green
no it will not be green
I have already visited google
so i have to write facebook
ok
so i will write facebook
what will happen if i do facebook 2
yes i have visited facebook
i have visited facebook
if you remember in initial few lectures I haven't visited it. I have visited it.
So that's why it's showing like this.
Now i'll tell you about 2 more links related.
One is a active.
If you type any pseudo selector, it shows you the image.
If i want the background color to be red.
So when i click on a link, it shows red.
Active means when you are clicking.
So here it is showing on google.com.
And when I click, its background will turn red.
I know that ideally you won't want to use this.
But that was just an example.
To show you how it works, it is easy for me to make the background red.
Because you will know it directly.
Now apart from anchor tag,, what do we have other than anchor tag?
Some pseudo selectors, the answer is yes, definitely.
One is hover, if I want that on anchor tag, anyone can hover.
And I want its background color to be red or yellow.
I make its background color yellow.
So if I hover, you can see here that its background color is be yellow so if i hover then you can see
that the background color is yellow
as i am hovering, i have written a hover and background color is yellow
so these were some pseudo selectors
now i will tell you one more pseudo selector
and that is, if i want to have a div
whose class is selector
and i will write I am selector
I'll put 1 here, so that you don't get confused
ONE
Now I'll tell you about first child pseudo selector
Which might be a little tricky for you
And this category is pseudo selector
So this pseudo selector
If I write P first child background color aqua
It means that wherever P is the first child of the parent, the background color will be aqua
Like in this case, you can see that I have put a main tag here
And it is written here P I am first and P I am second
So here you can see that wherever the first child of the main is P, which is here
This P is the first child of the main is P, which is here, this P is the first child of the parent.
So this class will be applied in this.
So see here,
its background has been acquired, and this has not.
But I will tell you again that such things are very rarely used when you do web development.
So you guys do more research about such pseudo classes.
What I will do in the description,
I will put links in the description about this type of things.
So if you want to see additional reading material
and pseudo classes,
then you will get the link
in the description.
Maybe I will put it in the pinned comment too.
And if I forget, then please remind me
that you have not given the link.
So I will give all the links to you.
From there you can read about these types of selectors.
But now we will move ahead in this course.
And we will read about the main things.
Because we have to come on projects very soon.
And we have to make real world apps.
And we have to do backend and database.
So we have to build pace.
I hope you are enjoying this course.
If you haven't bookmarked it yet, do it now. Click here and save it.
Access the playlist, gethub code, like the video, share it.
And name your village and uncle's land.
Thank you so much for watching this video.
And I will see you next time. Thanks for watching!
Voir Plus de Vidéos Connexes
5.0 / 5 (0 votes)