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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="wrapper">
  <div class="box">
    <div class="grid">
    </div>
  </div>
  <button id="one">Mode 1</button>
  <button id="two">Mode 2</button>
  <button id="three">Mode 3</button>
  <button id="four">Mode 4</button>
  <button id="five">Mode 5</button>
  <button id="reset">RESET</button>
</div>
!

CSS 

              
                body{
  background-color: #444;
  background: repeating-linear-gradient(45deg, #2b2b2b 0%, #2b2b2b 10%, #222222 0%, #222222 50%) 0 / 15px 15px;
}

button{
  background-color: #4d4d4d; 
  border: none;
  color: white;
  padding: 0.5rem 1rem;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  font-size: 12px;
}

.wrapper{
  text-align: center;
}

.box{
  margin: 2rem auto; 
  border: 5px solid #2d2d2d;
  height: 270px;
  width: 80px;
  border-radius: 10px;
}

.grid{
  display: grid;
  grid-auto-rows: 50px;
  gap: 1rem;
  padding: 10px;
}

.high-beam{
  background-color: #fff;
  height: 3rem;
  width: 3rem;
  border-radius: 50%;
  margin:  auto;
  box-shadow: 0 0 5px #fff, 0 0 10px #fff, 0 0 15px #fff, 0 0 20px red, 0 0 35px red, 0 0 40px red;
}

.low-beam{
  background-color: #fff;
  height: 3rem;
  width: 3rem;
  border-radius: 50%;
  margin:  auto;
  box-shadow: 0 0 5px #fff, 0 0 10px red, 0 0 15px red, 0 0 20px red, 0 0 35px red, 0 0 40px red;
}

.shine{
  background-color: #fff;
  animation: neon 0.2s ease infinite;
}

.alter-one{
  background-color: #fff;
  animation: neon 0.375s ease infinite;
}

.alter-two{
  animation: neon2 0.78s ease infinite;
}

.off{
  background-color: grey;
  box-shadow: none;
}

@keyframes neon {
  from {
    box-shadow: 0 0 10px #fff, 0 0 20px #fff, 0 0 30px #fff, 0 0 40px red, 0 0 70px red, 0 0 80px red, 0 0 100px red, 0 0 150px red, 0 0 200px red;
  }
  to {
    box-shadow: 0 0 5px #fff, 0 0 10px #fff, 0 0 15px #fff, 0 0 20px red, 0 0 35px red, 0 0 40px red, 0 0 50px red, 0 0 75px red;
  }
}

@keyframes neon2 {
  from {
    box-shadow: 0 0 10px #fff, 0 0 20px #fff, 0 0 30px #fff, 0 0 40px red, 0 0 70px red, 0 0 80px red, 0 0 100px red, 0 0 150px red, 0 0 200px red;
  }
  to {
    background-color: #fff;
  }
}
!

JS 

              
                const ledStates = [
  { name: "modeOne",
    state: [ "high-beam", "high-beam", "high-beam", "high-beam"]
  },
  { name: "modeTwo",
    state: [ "low-beam", "low-beam", "low-beam", "low-beam"]
  },
  { name: "modeThree",
    state: [ "high-beam shine", "high-beam shine", "high-beam shine", "high-beam shine"]
  },
  { name: "modeFour",
    state: [ "low-beam alter-two", "low-beam alter-one", "low-beam alter-one", "low-beam alter-two"]
  },
  { name: "modeFive",
    state: [ "low-beam alter-one", "low-beam alter-two", "low-beam alter-two", "low-beam alter-one"]
  }
];

function modeOne(arr) {
  // Remove current state
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  // Read js object for state
  const currentLedStates = ledStates.find((key) => key.name == 'modeOne').state.map((key) => `<div class='${key}'></div>`);
  
  // Create markup
  let markup = ``;
  currentLedStates.map(child => (markup += child));
  grid.innerHTML += markup;

  // Re-enable event listeners
  init();
}

function modeTwo(arr) {
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  // Read js object for state
  const currentLedStates = ledStates.find((key) => key.name == 'modeTwo').state.map((key) => `<div class='${key}'></div>`);
  
  // Create markup
  let markup = ``;
  currentLedStates.map(child => (markup += child));
  grid.innerHTML += markup;

  init();
}

function modeThree(arr) {
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  // Read js object for state
  const currentLedStates = ledStates.find((key) => key.name == 'modeThree').state.map((key) => `<div class='${key}'></div>`);
  
  // Create markup
  let markup = ``;
  currentLedStates.map(child => (markup += child));
  grid.innerHTML += markup;

  init();
}

function modeFour(arr) {
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  // Read js object for state
  const currentLedStates = ledStates.find((key) => key.name == 'modeFour').state.map((key) => `<div class='${key}'></div>`);
  
  // Create markup
  let markup = ``;
  currentLedStates.map(child => (markup += child));
  grid.innerHTML += markup;

  init();
}

function modeFive(arr) {
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  // Read js object for state
  const currentLedStates = ledStates.find((key) => key.name == 'modeFive').state.map((key) => `<div class='${key}'></div>`);
  
  // Create markup
  let markup = ``;
  currentLedStates.map(child => (markup += child));
  grid.innerHTML += markup;

  init();
}

function reset(arr) {
  initialState();
  init();
}

function init() {
  document.getElementById("one").addEventListener("click", modeOne);
  document.getElementById("two").addEventListener("click", modeTwo);
  document.getElementById("three").addEventListener("click", modeThree);
  document.getElementById("four").addEventListener("click", modeFour);
  document.getElementById("five").addEventListener("click", modeFive);
  document.getElementById("reset").addEventListener("click", reset);
}

function initialState() {
  const grid = document.querySelector(".grid");
  grid.innerHTML = ``;

  const innerLED = `<div class="low-beam off"></div>\
      <div class="low-beam off"></div>\
      <div class="low-beam off"></div>\
      <div class="low-beam off"></div>`;
  grid.innerHTML += innerLED;
}

initialState();
init();
!
999px

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