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<header id="top" class="page-title">CSS Selectors</header>
<ul class="nav-items">
<li><a href="#Introduction" class="nav-link">Introduction</a></li>
<li><a href="#What_You_Should_Already_Know" class="nav-link">What You Should Already Know</a></li>
<li><a href="#Simple_Selectors" class="nav-link">Simple Selectors</a></li>
<li><a href="#Attribute_Selectors" class="nav-link">Attribute Selectors</a></li>
<li><a href="#Pseudo-classes" class="nav-link">Pseudo-Classes</a></li>
<li><a href="#Pseudo-elements" class="nav-link">Pseudo-Elements</a></li>
<li><a href="#Combinators_and_Multiple_Selectors" class="nav-link">Combinators and Multiple Selectors</a></li>
<li><a href="#Where_To_Go_Next" class="nav-link">Where To Go Next</a></li>
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<section id="Introduction" class="main-section">
<header>Introduction</header>
<p>An important feature of <strong>CSS</strong> is the ability to apply style rules to a set of elements within an HTML document. If you had to style each element independently, for example:</p>
<pre>
<code>
<h3 style="color: purple;"></h3>
<p style="color: green"></p>
</code>
</pre>
<p>It would take a lot of effort and time to style these elements separately. When you use <strong>CSS Selectors</strong>, you can apply style rules for matching elements within an <strong>HTML</strong> document to change and edit their appearance. </p>
<pre>
<code>
h3 {color: purple;}
p {color: green;}
</code>
</pre>
<p>In this document, you will learn about:</p>
<ul>
<li>Simple and Attribute Selectors</li>
<li>Pseudo-Classes and Pseudo-Elements</li>
<li>Combinators and Multiple Selectors</li>
</ul>
</section><!--End Introduction-->
<!--What You Should Already Know-->
<section id="What_You_Should_Already_Know" class="main-section">
<header>What You Should Already Know</header>
<p>You should be familiar with CSS syntax, <strong>properties</strong> and <strong>values</strong>, and how they are paired to create a <strong>declarations</strong>. </p>
<ul>
<li>These declarations are put into <strong>CSS Declaration Blocks;</strong></li>
<li>The declaration blocks are placed with selectors that match HTML elements;</li>
<li>Selectors and declarations create <strong>CSS Rule Sets</strong>.</li>
</ul>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</section>
<!--Simple Selectors-->
<section id="Simple_Selectors" class="main-section">
<header>Simple Selectors</header>
<article>
<p><strong>Simple Selectors</strong> are also known as <strong>element, class, or id selectors</strong>. First, we will talk about element selectors. They match specific HTML elements, and they are not case-sensitve. Based on the HTML example below: </p>
<pre>
<code>
<h4>HTML Example</h4>
<p>I love coding!</p>
</code>
</pre>
<p>Now, there is the stylesheet that uses simple selectors to add rules to corresponding HTML elements: </p>
<pre>
<code>
/*All h4 elements will be purple */
h4 {
color: purple;}
/*All p elements will be green */
p {
color: green;}
</code>
</pre>
<p>Once the styles are added, we get the final result: </p>
<pre class="example1">
<h4>HTML Example</h4>
<p>I love coding!</p>
</pre>
<p><strong>Class Selectors</strong> must have a '.', followed by the class name. Remember, a class name is placed inside the HTML document, and it can have any value without spaces. Class names can also be group within a single element, and different elements can have the same class name. Look at the following HTML: </p>
<pre>
<code>
<h4 class="example-title intro">HTML Example</h4>
<p class="intro-text">I love coding!</p>
</code>
</pre>
<p>Then our stylesheet: </p>
<pre>
<code>
/*Element with the class "example-title" will be underlined */
.example-title {
text-decoration: underline;}
/*All elements with class "intro-text" will be green and bold */
.intro-text {
color: green;
font-weight: bold;}
</code>
</pre>
<p>We've added our styles to get the following result: </p>
<pre class="example2">
<h4 class="example-title">HTML Example</h4>
<p class="intro-text">I love coding!</p>
</pre>
<p>Finally, we have <strong>Id Selectors</strong>. Id selectors must be unique (elements cannot share the same id selectors). You need to use the hash/pound symbol (#) before the id name. Here's our HTML: </p>
<pre>
<code>
<h4 id="Intro-Title">HTML Example</h4>
<p id="Intro-Text">I love coding!</p>
</code>
</pre>
<p>Now our stylesheet: </p>
<pre>
<code>
/*Element with the id "Intro-Title" will be italic */
#Intro-Title {
font-style: italic;}
/*The p element with id "Intro-Text" will be green with an overline and underline*/
p { text-decoration: underline overline;
color: green;}
</code>
</pre>
<p>Let's look at our results: </p>
<pre class="example3">
<h4 id="Intro-Title">HTML Example</h4>
<p id="Intro-Text">I love coding!</p>
</pre>
<p>There is one last selector called the <strong>Universal Selectors</strong>. Universal selectors (*) allow programmers to select all elements in a page. This selector is usually combined with other selectors instead of being used to apply styles to every element. (See Also <a href="#Combinators_and_Multiple_Selectors">Combinators and Multiple Selectors</a>) Here's one HTML example: </p>
<pre>
<code class="Text-A">
<div>
<p>I like setting a Universal Selector to have an outline border.
This helps me to see the areas I need to style when designing a site. </p>
</div>
</code>
</pre>
<p>Let's look at this stylesheet: </p>
<pre>
<code>
/*Universal Selector will set an outline around the elements (div & p). */
* {
margin: 15px;
outline: 1px solid black;
box-sizing: border-box;
}
p {
background: white; }
div {
background: #be3737; }
</code>
</pre>
<p>Now for the result: </p>
<pre class="example4">
<div class="Text-Div">
<p class="Text">I like setting a Universal Selector to have an outline border. This helps me to see the areas I need to style when designing a site. </p>
</div>
</pre>
<p>We've gone through simple selectors. In the next section you will learn about more advanced selectors called <strong>Attribute Selectors</strong>. </p>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</article>
</section>
<!--Attribute Selectors-->
<section id="Attribute_Selectors" class="main-section">
<header>Attribute Selectors</header>
<article>
<p><strong>Attribute Selectors</strong> are selectors that match elements according to their <strong>attributes</strong> and <strong>attribute values</strong>. These selectors are surrounded by square brackets ([ ]). The attribute name and value are placed inside the brackets. Attribute selectors are divided into two categories: <i>Presence and value</i> and <i>Substring value</i>. When you use data-*, that are called <strong>data attributes</strong>. Data attributes are used to store custom data so they can be retrieved at a later time. </p>
<ul>
<h4>Presence and value</h4>
<li><strong>[attr]</strong>: This selector will choose all elements that have a specific attribute regardless of value. Example— <strong>[data-animal]</strong> { width: 80%;} </li><br>
<li><strong>[attr=val]</strong>: This selector will choose all elements that have a specific attribute only if its value equals val. Example— <strong>[data-animal="wild"]</strong> { width: 80%;}</li><br>
<li><strong>[attr~=val]</strong>: This selector will choose all elements that only have val as one of the space-separated list of words within the attr's value. Example— <strong>[data-animal~="tame"]</strong> { width: 80%;}</li><br>
<!--Codepen Example: Presence and Value-->
<div class="embed1">
<p data-height="265" data-theme-id="0" data-slug-hash="rqKKmZ" data-default-tab="html,result" data-user="TLanette" data-pen-title="Attribute Selectors: Presence&Value" class="codepen">See the Pen <a href="https://codepen.io/TLanette/pen/rqKKmZ/">Attribute Selectors: Presence&Value</a> by T.Lanette Pollard (<a href="https://codepen.io/TLanette">@TLanette</a>) on <a href="https://codepen.io">CodePen</a>.</p>
<script async src="https://static.codepen.io/assets/embed/ei.js"></script>
<p><small>Presence and Value example on Codepen. </small></p>
</div>
<h4>Substring Value</h4>
<li><strong>[attr^=val]</strong>: This selector will choose all elements that have a specific attribute and the value starts with val. Example— <strong>[data-quantity^="required"]</strong> { color: orange;} </li><br>
<li><strong>[attr$=val]</strong>: This selector will choose all elements that have a specific attribute only if its value ends with val. Example— <strong>[data-quantity$="ft"]</strong> { color: purple;}</li><br>
<li><strong>[attr*=val]</strong>: This selector will choose all elements that have a specific attribute where val is part of a string or substring.(String= "Food not raw") Example— <strong>[data-quantify*="not raw"]</strong> { color:green;}</li><br>
</ul>
<!--Codepen Example: Substring Value-->
<div class="embed2">
<iframe height='297' scrolling='no' title='AttributeSelector: Substring Value' src='//codepen.io/TLanette/embed/KGeBzb/?height=297&theme-id=0&default-tab=html,result' frameborder='no' allowtransparency='true' allowfullscreen='true' style='width: 100%;'>See the Pen <a href='https://codepen.io/TLanette/pen/KGeBzb/'>AttributeSelector: Substring Value</a> by T.Lanette Pollard (<a href='https://codepen.io/TLanette'>@TLanette</a>) on <a href='https://codepen.io'>CodePen</a>.
</iframe>
<p><small>Substring Value example on Codepen. </small></p>
</div>
<p>Next we're going to explore <strong>Pseudo-Classes</strong>.</p>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</article>
</section>
<!--Pseudo-classes-->
<section id="Pseudo-classes" class="main-section">
<header>Pseudo-Classes</header>
<p><strong>Pseudo-classes</strong> are part of the group of <strong>pseudo-selectors</strong>. Pseudo-selectors are used to select certain parts of elements or elements in certain situations. Pseudo-classes are keywords which are placed on the end of a selector after a colon (:). They are used in CSS to specify styles for a specific element in a certain state. Some of the common pseudo-classes are: </p>
<pre>
<code class="pseudo-class">
:active
:checked
:first
:first-child
:focus
:hover
:visited
</code>
</pre>
<p>Here's an example of HTML and CSS with pseudo-classes:</p>
<pre>
<code>
<a href="https://codepen.io/TLanette/full/zJNrNN/">R.F. Travel Services</a>
</code>
</pre><br>
<pre>
<code>
/*These are styles for the link in all states, visited, hover, active, and focus*/
a {
color: blue;
font-weight: bold; }
a:visited {
color: blue; }
a:hover, a:active, a:focus {
color: #4a0e5c;}
</code>
</pre>
<p>To see the result, click and hover over the link: </p>
<p><a class="landing-link" href="https://codepen.io/TLanette/full/zJNrNN/" target="_blank">R.F. Travel Services</a></p>
<p>The next type of pseudo-selectors we will discuss pseudo-elements. </p>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</section>
<!--Pseudo-elements-->
<section id="Pseudo-elements" class="main-section">
<header>Pseudo-elements</header>
<p><strong>Pseudo-elements</strong> are similar to pseudo-classes because they are also keywords. However, two colons (::) are used at the end of selectors </p>
<pre>
<code class="pseudo-elements">
::after
::before
::first-letter
::first-line
::selection
::backdrop
</code>
</pre><br>
<p>We can use pseudo-elements to style one area of a paragraph. Take a look at the following HTML and CSS samples:
<pre>
<code>
<p>Imagine recreating a paragraph with an illuminated letter like they did during the medieval times. </p>
</code>
</pre><br>
<pre>
<code>
p::first-letter {
font-size: 3em;
border: 1px solid black;
background: #be3737;
display: block;
float: left;
padding: 2px;
margin-right: 4px; }
</code>
</pre>
<p>The final result should highlight the first letter in the first line of the paragraph.</p><br>
<pre class="example5">
<div class="pseudo-div">
<p class="pseudo-text">Imagine recreating a paragraph with an illuminated letter like they did during the medieval times.</p>
</div>
</pre>
<p>In our last section, we will discuss <strong>Combinators and Multiple Selectors.</strong></p>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</section>
<!--Combinators and multiple selectors-->
<section id="Combinators_and_Multiple_Selectors" class="main-section">
<header>Combinators and Multiple Selectors</header>
<p>There are different ways for combining CSS selectors to make your programming more efficient. Selectors are grouped based on how they are related to each other. These relations are referred to as <strong>combinators</strong>. A and B will be used represent the selectors from the above sections. </p>
<ul>
<li><strong>Descendant Combinator: A B </strong>⇨ These are selectors represented by a single space character (_). The selectors are two elements (parent and child). <strong>Example:</strong> The p element that is the diret child of a div element. <strong><i>div</i> <i>p</i></strong> </li><br>
<li><strong>Child Combinator: A > B </strong>⇨ These selectors have a child combinator (>) between them. Both selectors are immediae children of the parent element. <strong>Example:</strong> Span elements that are children of a div element. <strong><i>div</i> > <i>span</i></strong> </li><br>
<li><strong>Adjacent Sibling Combinator: A + B </strong>⇨ An adjacent sibling combinator (+) is placed between two selectors where the second immediately follows the first. Both selectors are immediate children of the parent element. <strong>Example:</strong> A paragraph element that immediately follows a header element in the same div. <strong><i>h3</i> + <i>p</i></strong> </li><br>
<strong>General Sibling Combinator: A ~ B </strong>⇨ The general sibling combinator (~) separates two selectors where the second element follows the first element. The second element doesn't have to immediately follow the first element. Both elements have the same parent. <strong>Example:</strong> A unordered list element that follows a paragraph element after a header element in the same div. <strong><i>h3</i> ~ <i>ul</i></strong> </li><br>
</ul>
<p>There is one last piece of information about grouping selectors. You can apply the same CSS rule to a group of selectors that are separated by commas: </p>
<pre>
<code>
p, ul {
color: white;
font-weight: 700; }
h1,h2, h3, h4, h5, h6 {
color: burgundy;
text-decoration: underline; }
</code>
</pre>
<p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>
</section>
<!--Where To Go Next-->
<section id="Where_To_Go_Next" class="main-section">
<header>Where To Go Next</header>
<p>Now that you have explored the world of <strong>CSS Selectors</strong>, your next step would be to learn about the different types of property values in CSS. You can also visit <a href="https://developer.mozilla.org/en-US/" target="_blank">MDN Web Docs</a> for more information. </p>
<!-- <p><small><a href="#Introduction" class="return">Return to Top</a></small></p> <br>-->
</section>
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<p><small><a href="#Introduction">Back to Top</a></small></p>
<p><small>Credit: <a href="https://developer.mozilla.org/en-US/docs/Learn/CSS/Introduction_to_CSS/Selectors">MDN Web Docs: Selectors</a></small></p>
<p><small>©2018 T.Lanette Pollard, <a href="www.rogetfreelancing.com">Roget Freelancing</a></small><br> <small>A <a href="https://freecodecamp.org">FreeCodeCamp.org</a> Project on <a href="https://codepen.io/TLanette/">Codepen</a></p>
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Hello Camper!
For now, the test suite only works in Chrome! Please read the README below in the JS Editor before beginning. Feel free to delete this message once you have read it. Good luck and Happy Coding!
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/*Colors: e6b31e, 343434, fcfaf1, cacaca; c4f0c5, f7f7f7, ece8d9; Colors Used: 6a0000, be3737, c4f0c5, f1fff1, eeeeee*/
/* Mobile First Styling */
* { /*
outline: 1px black solid;*/
box-sizing: border-box;
}
html, body {
min-width: 400px;
background-color: #f1fff1;
background-image: linear-gradient(#f1fff1, #c4f0c5);
}
body {
margin: 0;
padding: 0;
}
body, nav, main, footer {
display: flex;
flex-direction: column;
}
#navbar header {
display: flex;
color: #f1fff1;
height: 100px;
width: 100%;
top: 0;
bottom: 0;
justify-content: center;
align-items: center;
font-size: 1.8em;
background-color: #be3737;
border-width:2px;
border-bottom-style:outset;
}
p{
font-size: 18px;
}
p small {
font-size: 14px;
}
pre, code {
direction: ltr;
text-align: left;
}
pre {
white-space: pre-wrap;
white-space: -moz-pre-wrap;
white-space: -pre-wrap;
white-space: -o-pre-wrap;
word-wrap: break-word;
font-size: 1.2em;
color: black;
margin: 5px auto;
padding: 5px 45px;
text-align: left;
width: 85%;
background-color: #eeeeee;
}
/* Pre Example 1 */
.example1 {
line-height: 0.20px;
text-align: center;
}
.example1 h4 {
color: purple;
}
.example1 p{
color: green;
}
/*Pre Example 2*/
.example2{
line-height: .20px;
text-align: center;
}
.example-title {text-decoration: underline;}
.intro-text {font-weight: bold; color: green;}
/*Pre Example3*/
.example3{
line-height: .20px;
text-align: center;
}
#Intro-Title {
font-style: italic;
}
#Intro-Text{
text-decoration: underline;
color: green;
}
/*Pre Example4*/
.Text-Div {
margin: 10px auto;
width: 90%;
outline: 1px solid black;
background: #be3737;
}
.Text {
margin: 15px;
outline: 1px solid black;
background: white;
}
code {
font-size: .8em;
}
.pseudo-class, .pseudo-elements {
color: #4a9ff5;
}
p.pseudo-text::first-letter {
font-size: 3em;
border: 1px solid black;
background: #5f1854;
display: block;
float: left;
padding: 0px 1px;
margin-top: -10px;
margin-right: 4px;
}
a.landing-link {
color: #be3737;
}
a.landing-link:visited {
color: black;
}
a.landing-link:hover, a.landing-link:active, a.landing-link:focus {
color: #6a0000;
}
.embed1, .embed2 {
margin: auto;
width: 80%;
}
/* Top Nav */
#navbar {
position: absolute;
padding: 0;
margin: 0;
width: 100%;
max-height: 290px;
height: 100%;
border-bottom: ;
z-index: 1;
}
#navbar ul {
background-color: #be3737;
height: 50%;
width 100%;
margin-top: 0px;
padding: 10px 50px 0px 50px;
overflow-y: auto;
overflow-x: hidden;
}
#navbar ul li {
list-style-type: none;
position: relative;
border: 1px solid gray;
box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
width: 100%;
margin-bottom: 20px;
}
#navbar a:link {
background-color: #cacaca;
width: 100%;
color: black;
padding: 10px 20px;
text-align: center;
text-decoration: none;
display: inline-block;
}
#navbar a:visited {
background-color: #f1fff1;
color: black;
}
/*Links on mouse-over */
#navbar a:hover {
background-color: #6a0000;
color: #f1fff1;
cursor: pointer;
}
/* Active/current link*/
#navbar li:active {
background-color: #f1fff1;
color: black;
}
/* Main Page */
#main-doc {
position: relative;
margin-top: 280px;
padding: 20px;
margin-bottom: 20px;
}
#main-doc ul {
font-size: 18px;
}
section:not(:last-child) {
padding-top: 40px;
padding-bottom: 40px;
margin-bottom: 40px;
border-bottom: 1px solid gray;
}
#main-doc header {
text-align: left;
margin: -10px 0px 0px 0px;
font-size: 28px;
font-weight: 700;
color: #6a0000;
}
a:link.return {
color: #be3737!important;
float: right;
margin-top: 5px;
margin-bottom: 45px;
margin-right: 10px;
text-decoration: none;
border: 1px solid gray;
}
/* Footer Styling */
footer {
background-color: #c4f0c5;
justify-content: space-evenly;
align-items: center;
text-align: center;
width: 100%;
height: 300px;
margin-top: 80px;
padding: 20px 0px 0px;
border-width: 1px;
border-top-style: inset;
}
footer p {
color: #6a0000;
}
footer a:link {
color: #6a0000;
text-decoration: none;
}
footer a:visited {
color: black;
}
/* Media Query*/
/* Screens more than 700px wide, sidebar becomes topbar */
@media only screen and (min-width: 700px) {
#navbar {
position: fixed;
max-height: 100%;
width: 320px;
z-index: ;
top: 0;
left: 0;
border-right: 0.5px solid gray;
box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.8);
}
#navbar ul {
height: 100%;
padding: 20px 20px 0px 20px;
margin-top: 0;
margin-bottom: 0;
}
#navbar ul li {
margin-bottom: 20px;
border: 1px solid gray;
border-radius: 2px;
box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
}
#main-doc {
margin-top: 30px;
margin-left: 350px;
margin-right: 50px;
padding: 0px 10px;
}
#main-doc section {
padding: 10px;
}
footer {
flex-direction: row;
justify-content: space-between;
align-items: center;
text-align: left;
height: 180px;
padding-top: 20px;
border-width: 1px;
border-top-style: inset;
}
footer p {
margin: 0px 20px;
}
}
// !! IMPORTANT README:
// You may add additional external JS and CSS as needed to complete the project, however the current external resource MUST remain in place for the tests to work. BABEL must also be left in place.
/***********
INSTRUCTIONS:
- Select the project you would
like to complete from the dropdown
menu.
- Click the "RUN TESTS" button to
run the tests against the blank
pen.
- Click the "TESTS" button to see
the individual test cases.
(should all be failing at first)
- Start coding! As you fulfill each
test case, you will see them go
from red to green.
- As you start to build out your
project, when tests are failing,
you should get helpful errors
along the way!
************/
// PLEASE NOTE: Adding global style rules using the * selector, or by adding rules to body {..} or html {..}, or to all elements within body or html, i.e. h1 {..}, has the potential to pollute the test suite's CSS. Try adding: * { color: red }, for a quick example!
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