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HTML

              
                <html>
  <head>
    <meta charset="utf-8" />
    <title>React Todo App</title>
    <meta name="viewport" description="width=device-width, initial-scale=1" />
  </head>
  
  <body>
    <div class="app-container" id="appContainer"></div>
  </body>
</html>
              
            
!

CSS

              
                // Remy function
@function remy($value, $base: 16px) {
  @return ($value / $base) * 1rem;
}

// Variables
$color-primary: #039be5;
$color-secondary: #eee;
$radius: 4px;

// Base
html {
  font-size: 16px;
}

body {
  font-size: 100%;
  font-family: 'Roboto', arial, sans-serif;
  background: #f9f9f9;
}

// Custom styles
.app-container {
  margin-top: 2rem;
  margin-right: auto;
  margin-left: auto;
  overflow: hidden;
  max-width: remy(420px);
  background: #fff;
  border-radius: $radius;
  box-shadow: 0 1px 3px rgba(0,0,0,.025), 0 3px 6px rgba(0,0,0,.065);
}

.app-header {
  position: relative;
  //min-height: remy(260px);
}

h1 {
  margin-bottom: 0;
  width: 100%;
  text-align: center;
}

.input-group .form-control:not(:last-child) {
  padding-top: .6rem;
  padding-bottom: .6rem;
  width: 70%;
  border-bottom: 0;
  border-left: 0;
  border-color: $color-secondary;
}

.input-group-addon {
  padding-top: 10.5px;
  padding-bottom: 10.5px;
  min-width: remy(80px);
  width: 30%;
  color: #fff;
  background-color: $color-primary;
  border: 0;
  border-radius: 0;
  
  &:focus {
    outline: 0;
  }
}

.task-list {
  padding: 0;
  margin-bottom: 0;
  margin-left: 0;
  overflow: hidden;
  list-style-type: none;
}

.task-item {
  padding-top: 0.75rem;
  padding-right: 0.75rem;
  padding-bottom: 0.75rem;
  padding-left: 0.75rem;
  width: 100%;
  background: #fff;
  cursor: default;
  border-top: 1px solid $color-secondary;
  
  &:last-of-type {
    border-bottom: 1px solid $color-secondary;
  }
}

.task-remover {
  line-height: 1.45;
  color: #ddd;
  cursor: pointer;
  transition: color .25s ease-in-out;
  
  &:focus,
  &:hover {
    color: #e53935;
  }
}
              
            
!

JS

              
                // Store app container in variable
const appContainer = document.querySelector('#appContainer');

// Create component for app header composed of input and button
const AppHead = ({addTask}) => {
  // Input Tracker
  let input;
  
  // Return AppHead component
  return (
    <div className='input-group'>
      <input ref={node => {
        input = node;
      }} className='form-control' type='text' />

      <button onClick={() => {
        addTask(input.value);
        input.value = '';
      }} className='input-group-addon'>
        Add task
      </button>
    </div>
  );
};

// Create component for new task composed of list item, text and icon
const Task = ({task, remove}) => {
  // For each task create list item with specific text and icon to remove the task
  return (
    <li className='task-item'>{task.text} <span className='fa fa-trash-o task-remover pull-right' onClick={() => {remove(task.id)}}></span></li>
  );
}

// Create component for list of tasks
const AppList = ({tasks,remove}) => {
  // Create new node for each task
  const taskNode = tasks.map((task) => {
    return (<Task task={task} key={task.id} remove={remove}/>)
  });

  // Return the list component with all tasks
  return (<ul className='task-list'>{taskNode}</ul>);
}

// Create global variable for task id
window.id = 0;

// Create main task app component
class TaskApp extends React.Component {
  constructor(prop) {
    // Provide parent class with prop
    super(prop);

    // Set initial state as empty
    this.state = {
      data: []
    }
  }

  // Add task handler
  addTask(val) {
    // Get the data for tasks such as text and id
    const task = {
      text: val,
      id: window.id++
    }
    
    // Update data if input contains some text
    if (val.length > 0) this.state.data.push(task);
    
    // Update state with newest data - append new task
    this.setState({
      data: this.state.data
    });
  }
  
  // Handle remove
  removeTask(id) {
    // Filter all tasks except the one to be removed
    const taskCollection = this.state.data.filter((task) => {
      if (task.id !== id) return task;
    });

    // Update state with filtered results
    this.setState({
      data: taskCollection
    });
  }

  render() {
    // Render whole App component
    // use AppHead and AppList components
    return (
      <div>
        <AppHead addTask={this.addTask.bind(this)}/>

        <AppList 
          tasks={this.state.data}
          remove={this.removeTask.bind(this)}
        />
      </div>
    );
  }
}

// Finally, render the whole app
ReactDOM.render(<TaskApp />, appContainer);
              
            
!
999px

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