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HTML

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About the <head>

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div id="root"></div>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Montserrat:700|Open+Sans:400,700');

:root {
  --text-color: rgba(38, 40, 45, 1);
  --secondary-text-color: rgba(255, 255, 255, .65);
  --hidden-text-color: rgba(38, 40, 45, 0);
  --primary-color: white;
  --secondary-color: rgba(103, 118, 140, 1);
  --secondary-color-hover: rgba(70, 146, 252, 1);
  --tertiary-color: rgba(215, 219, 230, 1);
}

* {
  padding: 0;
  margin: 0;
  border: 0;
  box-sizing: border-box;
}

body {
  background-color: var(--tertiary-color);
  font-family: 'Open Sans';
}

.tabs {
  font-weight: 400;
}

.tabs a {
  text-decoration: none;
  color: inherit;
}

.tabs h2 {
  font-size: 36px;
  margin-bottom: 15px;
  text-transform: capitalize;
  font-family: 'Montserrat', sans-serif;
}

.tab {
  padding: 14px 12px 14px 20px;
  background-color: var(--secondary-color);
  color: var(--secondary-text-color);
  width: max-content;
  float: left;
  margin-left: -1px;
  position: relative;
  z-index: 0;
  transition: top .5s ease 0s, 
    border .5s ease 0s, 
    color .5s ease 0s, 
    background-color .5s ease 0s,
    border-top-left-radius .5s ease 0s;
  top: 0;
}

.tab:hover {
  cursor: pointer;
  top: -3px;
  background-color: var(--secondary-color-hover);
  color: var(--text-color);
  z-index: 2;
  border-top-left-radius: 5px;s
}

.tab::after {
  content: '';
  display:block;
  width: 0;
  height: 0;
  border-right: 20px transparent solid;
  border-bottom: 60px var(--secondary-color) solid;
  z-index: 0;
  position: absolute;
  top:0;
  left: 100%;
  transition: border-bottom .5s ease 0s;
}

.tab:hover::after {
  content: '';
  display:block;
  width: 0;
  height: 0;
  border-right: 20px transparent solid;
  border-bottom: 60px var(--secondary-color-hover) solid;
  z-index: 2;
  position: absolute;
  top:0;
  left: 100%;
}

.tab:first-child {
  margin-left: 0;
  border-top-left-radius: 5px;
}



.tab:focus {
  outline: none;
}

.tabs .active {
  top: -3px;
  color: var(--text-color);
  z-index: 3;
  background-color: var(--primary-color);
  border-top-left-radius: 5px;
}

.tab.active::after {
  border-bottom: 60px var(--primary-color) solid;
}

section {
  margin: 15px auto;
  width: 700px;
}

.tabs menu ul {
  list-style: none;
}

.tabs menu + div {
  clear: both;
  margin-top: 15px;
  padding: 15px 0;
  color: white;
  line-height: 1.5;
  color: rgba(255,255,255,.6);
  position: relative;
}

.tabs menu + div > div > hr {
  height: 2px;
  width: 33%;
  opacity: 0;
  transition: opacity .5s ease 0s;
  margin-bottom: 15px;
  background-color: var(--secondary-color);
}

.tabs menu + div > div {
  visibility: hidden;
  color: var(--hidden-text-color);
  transition: color .5s ease 0s;
  padding: 20px;
  position: absolute;
  top: 0;
  width: 100%;
  background-color:  rgb(24, 26, 30);
}

.tabs menu + div > .active {
  visibility: visible;
  color: var(--text-color);
  border-bottom: 1px var(--tertiary-color) solid;
  transition: color 1s ease 0s;
  border-radius: 0 5px 5px 5px;
}

.tabs menu + div > div.active > hr {
  opacity: .5;
}
!

JS 

              
                const Component = React.Component;

const TAB_DATA = [
  ["about", "lorem ipsum dolor sit amet"],
  ["contact", "Curabitur in augue erat. Vestibulum in fermentum ante, sit amet consectetur neque. Maecenas tempor nisl sollicitudin, blandit sapien ut, fermentum metus."],
  ["portfolio", "Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Aliquam aliquam, nisi vitae maximus tincidunt, justo leo auctor neque, et fermentum ante libero ac libero."],
  ["cool stuff", "Nullam lacinia ipsum metus, ut varius tortor egestas non. Fusce lobortis, dolor ut venenatis posuere, diam neque mattis risus, vulputate sodales eros urna a turpis. Vivamus pretium condimentum faucibus. Nullam laoreet, mauris vitae vulputate vulputate, justo felis facilisis lorem, sed elementum metus leo eget nisl."],
  ["another tab", "Vivamus sit amet ante vitae tortor condimentum blandit. Nunc a purus dui. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Donec dapibus porttitor diam. Aenean sit amet accumsan orci. Phasellus eget justo ante. Morbi fringilla aliquam lectus."],
  ["another blab", "Vivamus sit amet ante vitae tortor condimentum blandit. Nunc a purus dui. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Donec dapibus porttitor diam. Aenean sit amet accumsan orci. Phasellus eget justo ante. Morbi fringilla aliquam lectus."]
];

class Tabs extends Component {
  constructor(props) {
    super(props);
    this.state = {
      active: 0
    }
  }
  
  clickHandler = (e) => {
    this.setState({
      active: parseInt(e.currentTarget.attributes.tabIndex.value)
    })
  }
  
  render() {
    let tabs = [];
    let contents = [];
    TAB_DATA.map(([label, text], i) => {
      const myStyle = {
        zIndex: this.state.active === i ? TAB_DATA.length : TAB_DATA.length - i - 1
      };
      
      tabs.push(<li 
               className={this.state.active === i ? "tab active" : "tab" } 
               key={label} 
               tabIndex={i}
               onClick={this.clickHandler}
               style={myStyle}>
          <a href={"#" + label}>{label}</a>
      </li>);
      
      contents.push(<div style={{zIndex: TAB_DATA.length}} className={this.state.active === i ? "active" : "" } key={label}><h2 id={label}>{label}</h2><hr/><p>{text}</p></div>);
    });
    
    return ( 
      <section className="tabs">
        <menu>
          <ul>
            {tabs}
          </ul>
        </menu>
        <div>
          {contents}
        </div>
      </section>);
  }
}

const App = () => {
  return (
        <Tabs />
  )
}

ReactDOM.render(<App />, document.getElementById("root"));
!
999px

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