:root {
  --option-bg: #f3f3f3;
  --option-hover-bg: #efefef;
  --option-color: #000000;
  --option-unselected-bg: #ffffd5;
  --error-color: #f32828;
  --accent-light-color: #45b87e;
  --accent-dark-color: #35a26b;
  --font-color-for-accent-bg: #ffffff;
  --main-font-style: 'Open Sans', sans-serif;
  --main-font-color: #000000;
  --main-font-size: 16px;
  --header-bg: #4581b5;
  --header-color: #ffffff;
}

.body {
  min-height: 100vh;
  position: relative;
  font-size: var(--main-font-size);
  font-family: var(--main-font-style);
  color: var(--main-font-color);
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1000px;
  margin: auto;
  padding: 20px;
}

.main-btn {
  background-color: var(--accent-light-color);
  border: none;
  padding: 10px 20px;
  font-size: var(--main-font-size);
  color: var(--font-color-for-accent-bg);
  display: block;
  min-width: 100px;
  cursor: pointer;
  -webkit-transform: perspective(1px) translateZ(0);
  transform: perspective(1px) translateZ(0);
  -webkit-transition-duration: 0.3s;
  transition-duration: 0.3s;
  -webkit-transition-property: background-color;
  transition-property: background-color;
  outline: none;
}

.main-btn:hover {
  background-color: var(--accent-dark-color);
}

.main-btn:disabled {
  background-color: var(--option-hover-bg);
  color: #ccc;
  cursor: default;
}

.left-btn {
  margin: 0 auto 0 0;
}

.right-btn {
  margin: 0 0 0 auto;
}

.question-footer {
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  margin-top: 20px;
}

@media screen and (max-width: 500px) {
  .main-btn {
    min-width: 0;
  }
}
