Reports

const up_vote_span = document.querySelector('.up-vote');
const down_vote_span = document.querySelector('.down-vote');
let count = document.querySelector('.number');

let upVote = false;
let downVote = false;

up_vote_span.addEventListener('click', function() {

  if (downVote === true) {

    up_vote_span.style.color = "#3CBC8D";
    down_vote_span.style.color = "dimgray";
    count.innerHTML = parseInt(count.innerHTML) + 2;
    upVote = true;
    downVote = false;

  } else if (upVote === false) {
    up_vote_span.style.color = "#3CBC8D";
    count.innerHTML = parseInt(count.innerHTML) + 1;
    upVote = true;
  } else if (upVote === true) {
    up_vote_span.style.color = "dimgray";
    count.innerHTML = parseInt(count.innerHTML) - 1;
    upVote = false;
  }
});

down_vote_span.addEventListener('click', function() {

  if (upVote === true) {
    up_vote_span.style.color = "dimgray";
    down_vote_span.style.color = "#3CBC8D";
    count.innerHTML = parseInt(count.innerHTML) - 2;
    downVote = true;
    upVote = false;
  } else if (downVote === false) {
    down_vote_span.style.color = "#3CBC8D";
    count.innerHTML = parseInt(count.innerHTML) - 1;
    downVote = true;
  } else if (downVote === true) {
    down_vote_span.style.color = "dimgray";
    count.innerHTML = parseInt(count.innerHTML) + 1;
    downVote = false;
  }
});

.number {
  display: inline-block;
  text-align: center;
}

.vote {
  display: flex;
  flex-direction: column;
  text-align: center;
}

.up-vote {
  color: dimgray;
  cursor: pointer;
}

.down-vote {
  cursor: pointer;
  color: dimgray;
}

<!DOCTYPE html>
<html lang="en" dir="ltr">

<head>
  <meta charset="utf-8">
  <title></title>
  <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.6.3/css/all.css" integrity="sha384-UHRtZLI+pbxtHCWp1t77Bi1L4ZtiqrqD80Kn4Z8NTSRyMA2Fd33n5dQ8lWUE00s/" crossorigin="anonymous">
</head>


  <div class="vote">
    <span class="up-vote"><i class="fas fa-angle-up"></i></span>
    <span class="number">990</span>
    <span class="down-vote"><i class="fas fa-angle-down"></i></span>
  </div>

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