How do I put one container above the other in css?

Question

Right now the ".controls" is on top of "container1" but I want that to be flipped so I can write some text in container1 above the buttons... how do I do that? This code is for an interactive multiple choice quiz and this contain1 is only used on the starting page to introduce the topic of the quiz before they click start.

*,
*::before,
*::after {
  box-sizing: border-box;
  font-family: Gotham Rounded;
}

 :root {
  --hue-neutral: 200;
  --hue-wrong: 0;
  --hue-correct: 145;
}

body {
  --hue: var(--hue-neutral);
  padding: 0;
  margin: 0;
  display: flex;
  width: 100vw;
  height: 100vh;
  justify-content: center;
  align-items: center;
  background-color: hsl(var(--hue), 100%, 20%);
}

body.correct {
  --hue: var(--hue-correct);
}

body.wrong {
  --hue: var(--hue-wrong);
}

.container {
  width: 800px;
  max-width: 80%;
  background-color: white;
  border-radius: 5px;
  padding: 10px;
  box-shadow: 0 0 10px 2px;
}

.btn-grid {
  display: grid;
  grid-template-columns: repeat(2, auto);
  gap: 10px;
  margin: 20px 0;
}

.btn {
  --hue: var(--hue-neutral);
  border: 1px solid hsl(var(--hue), 100%, 30%);
  background-color: hsl(var(--hue), 100%, 50%);
  border-radius: 5px;
  padding: 5px 10px;
  color: white;
  outline: none;
}

.btn:hover {
  border-color: black;
}

.btn.correct {
  --hue: var(--hue-correct);
  color: black;
}

.btn.wrong {
  --hue: var(--hue-wrong);
}

.start-btn,
.next-btn {
  font-size: 1.5rem;
  font-weight: bold;
  padding: 10px 20px;
}

.container1 {
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: Arial, sans-serif;
  font-size: xx-large;
}

.controls {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hide {
  display: none;
}

.wrapper {
  position: absolute;
  top: 0px;
  right: 0px;
}

<div class="container">
  <div id="question-container" class="hide">
    <div id="question">Question</div>
    <div id="answer-buttons" class="btn-grid">
      <button class="btn">Answer 1</button>
      <button class="btn">Answer 2</button>
      <button class="btn">Answer 3</button>
      <button class="btn">Answer 4</button>
    </div>
  </div>
  <div class="controls">
    <button id="start-btn" class="start-btn btn">Start</button>
    <button id="next-btn" class="next-btn btn hide">Next</button>
  </div>
  <div class="container1">
    <div id="startmsgcontainer" class="hide"></div>
    <div id="startmsg">Startmsg</div>
  </div>
</div>
<div class="wrapper">
  <img src="uni.png" alt="image">
</div>

Answer 1

Add the following to .container:

.container {
  …
  flex-direction: column-reverse;
  display: flex;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  font-family: Gotham Rounded;
}

 :root {
  --hue-neutral: 200;
  --hue-wrong: 0;
  --hue-correct: 145;
}

body {
  --hue: var(--hue-neutral);
  padding: 0;
  margin: 0;
  display: flex;
  width: 100vw;
  height: 100vh;
  justify-content: center;
  align-items: center;
  background-color: hsl(var(--hue), 100%, 20%);
}

body.correct {
  --hue: var(--hue-correct);
}

body.wrong {
  --hue: var(--hue-wrong);
}

.container {
  width: 800px;
  max-width: 80%;
  background-color: white;
  border-radius: 5px;
  padding: 10px;
  box-shadow: 0 0 10px 2px;
  display: flex;
  flex-direction: column-reverse;
}

.btn-grid {
  display: grid;
  grid-template-columns: repeat(2, auto);
  gap: 10px;
  margin: 20px 0;
}

.btn {
  --hue: var(--hue-neutral);
  border: 1px solid hsl(var(--hue), 100%, 30%);
  background-color: hsl(var(--hue), 100%, 50%);
  border-radius: 5px;
  padding: 5px 10px;
  color: white;
  outline: none;
}

.btn:hover {
  border-color: black;
}

.btn.correct {
  --hue: var(--hue-correct);
  color: black;
}

.btn.wrong {
  --hue: var(--hue-wrong);
}

.start-btn,
.next-btn {
  font-size: 1.5rem;
  font-weight: bold;
  padding: 10px 20px;
}

.container1 {
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: Arial, sans-serif;
  font-size: xx-large;
}

.controls {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hide {
  display: none;
}

.wrapper {
  position: absolute;
  top: 0px;
  right: 0px;
}

<div class="container">
  <div id="question-container" class="hide">
    <div id="question">Question</div>
    <div id="answer-buttons" class="btn-grid">
      <button class="btn">Answer 1</button>
      <button class="btn">Answer 2</button>
      <button class="btn">Answer 3</button>
      <button class="btn">Answer 4</button>
    </div>
  </div>
  <div class="controls">
    <button id="start-btn" class="start-btn btn">Start</button>
    <button id="next-btn" class="next-btn btn hide">Next</button>
  </div>
  <div class="container1">
    <div id="startmsgcontainer" class="hide"></div>
    <div id="startmsg">Startmsg</div>
  </div>
</div>
<div class="wrapper">
  <img src="uni.png" alt="image">
</div>