HTML Slider’s CSS not doing anything when I add custom HTML to a page

I’m using a slider for my page but the css is not affecting the slider.
Here is the HTML code:

<h1>Random Brawlers Generator</h1>

<div class="slidecontainerss">
  <h3>Number of Brawlers to generate:</h3>
  <br>
  <input type="range" id="rangeInput" min="1" max="10" value="3" class="sliderss" oninput="numInput.value=rangeInput.value">
  <input type="number" id="numInput" min="1" max="10" class="sliderValss" value="3" oninput="rangeInput.value=numInput.value">
</div>
<label class="container">Allow repeated Brawlers
  <input type="checkbox" id="repeatBrawlers">
  <span class="checkmark"></span>
</label>
<label class="container">Randomly generate Star Powers
  <input type="checkbox" id="randomStarPowers">
  <span class="checkmark"></span>
</label>
<label class="container">Exclude Brawlers
  <input type="checkbox" id="excludeBrawlers">
  <span class="checkmark"></span>
</label>
<button onclick="main()">Generate</button>
<p id="gg">d</p>
<img id="image" >

<div class="groupContainer">
  <div style="background-color:coral;" id="group1">

  </div>
  <div style="background-color:lightblue;" id="group2">
    
  </div>
  <div style="background-color:coral;" id="group3">

  </div>
  <div style="background-color:lightblue;" id="group4">
    
  </div>
  <div style="background-color:coral;" id="group5">

  </div>
  <div style="background-color:lightblue;" id="group6">
    
  </div>
  <div style="background-color:coral;" id="group7">

  </div>
  <div style="background-color:lightblue;" id="group8">
    
  </div>
  <div style="background-color:coral;" id="group9">

  </div>
  <div style="background-color:lightblue;" id="group10">
    
  </div>
  <div style="background-color:coral;" id="group11">

  </div>
  <div style="background-color:lightblue;" id="group12">
    
  </div>
  <div style="background-color:coral;" id="group13">

  </div>
  <div style="background-color:lightblue;" id="group14">
    
  </div>
  <div style="background-color:coral;" id="group15">

  </div>
  <div style="background-color:lightblue;" id="group16">
    
  </div>
  <div style="background-color:coral;" id="group17">

  </div>
  <div style="background-color:lightblue;" id="group18">
    
  </div>
  <div style="background-color:coral;" id="group19">

  </div>
  <div style="background-color:lightblue;" id="group20">
    
  </div>
  <div style="background-color:coral;" id="group21">

  </div>
  <div style="background-color:lightblue;" id="group22">
    
  </div>
  <div style="background-color:coral;" id="group23">

  </div>
  <div style="background-color:lightblue;" id="group24">
    
  </div>
  <div style="background-color:coral;" id="group25">

  </div>
  <div style="background-color:lightblue;" id="group26">
    
  </div>
  <div style="background-color:coral;" id="group27">

  </div>
  <div style="background-color:lightblue;" id="group28">
    
  </div>
  <div style="background-color:coral;" id="group29">

  </div>
  <div style="background-color:lightblue;" id="group30">
    
  </div>
  <div style="background-color:lightblue;" id="group31">
    
  </div>
  <div style="background-color:lightblue;" id="group32">
    
  </div>
  <div style="background-color:lightblue;" id="group33">
    
  </div>
</div>

Here is the CSS:

.slidecontainer {
  width: 100%;
  border-radius: 50px;
}

.slider {
  -webkit-appearance: none;
  width: 200px;
  height: 15px;
  border-radius: 5px;
  background: #d3d3d3;
  outline: none;
  opacity: 0.7;
  -webkit-transition: .2s;
  transition: opacity .2s;
}

.slider:hover {
  opacity: 1;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 25px;
  height: 25px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}

.slider::-moz-range-thumb {
  width: 25px;
  height: 25px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}

.container {
  display: block;
  width: 500px;
  position: relative;
  padding-left: 35px;
  margin-bottom: 12px;
  cursor: pointer;
  font-size: 22px;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}

/* Hide the browser's default checkbox */
.container input {
  position: absolute;
  opacity: 0;
  cursor: pointer;
  height: 0;
  width: 0;
}

/* Create a custom checkbox */
.checkmark {
  position: absolute;
  top: 0;
  left: 0;
  height: 25px;
  width: 25px;
  background-color: #eee;
}

/* On mouse-over, add a grey background color */
.container:hover input ~ .checkmark {
  background-color: #ccc;
}

/* When the checkbox is checked, add a blue background */
.container input:checked ~ .checkmark {
  background-color: #2196F3;
}

/* Create the checkmark/indicator (hidden when not checked) */
.checkmark:after {
  content: "";
  position: absolute;
  display: none;
}

/* Show the checkmark when checked */
.container input:checked ~ .checkmark:after {
  display: block;
}

/* Style the checkmark/indicator */
.container .checkmark:after {
  left: 9px;
  top: 5px;
  width: 5px;
  height: 10px;
  border: solid white;
  border-width: 0 3px 3px 0;
  -webkit-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  transform: rotate(45deg);
}

.sliderVal{
  width: 70px;
border-radius: 5px;
border: solid grey;
}

.groupContainer{
  width: 500px;
  height: 500px;
  border: 5px solid #c3c3c3;
  display: flex;
  flex-wrap: wrap;
}

.groupContainer div {
  width: 40px;
  height: 40px;
  margin-right: 20px;
}

The CSs works on other things just not on the slider. Thanks for any help!

• This topic was modified 6 years, 1 month ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic