* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 62.5%;
}

body {
  font-family: "Rubik", sans-serif;
  background-color: #f7f7f7;
}

.container {
  padding: 2.4rem 4.8rem;
  position: relative;
}

.time-points {
  margin-bottom: 2.4rem;

  display: flex;
  justify-content: space-around;
  align-items: center;
}

.time-points {
  font-size: 3.2rem;
}

.container-num {
  display: flex;
  align-items: center;
  column-gap: 2rem;
}

.change-high-num {
  background-color: #f07b3f;
  padding: 1rem;
  border-radius: 10px;
}

.signs {
  display: flex;
  justify-content: space-around;

  margin-bottom: 4.8rem;
}

.backdrop {
  height: 100vh;
}

.sign {
  font-size: 6rem;
  width: 8rem;
  height: 8rem;
  background-color: #ffa94d;
  border-radius: 50%;

  display: flex;
  justify-content: center;
  align-items: center;
}

.equation {
  display: flex;
  justify-content: center;
  align-items: center;
  column-gap: 2rem;

  margin-bottom: 4.8rem;
}

.num {
  font-size: 9rem;
  min-width: 16rem;
  height: 16rem;
  background-color: #a5d8ff;
  border-radius: 10px;

  display: flex;
  justify-content: center;
  align-items: center;
}

.equal,
.first-num,
.second-num {
  background-color: #ced4da;
}

.answer-options {
  display: flex;
  justify-content: space-around;
}

.num,
.sign {
  user-select: none;
}

.clickable {
  box-shadow: 0px 0px 1rem #505050;
  cursor: pointer;
}

.answer-options,
.signs {
  justify-content: space-between;
  padding: 2rem;
  border: 3px solid black;
  background-color: #e7f5ff;
  border-radius: 10px;
}

.backdrop {
  height: 100vh;
  width: 100vw;
  position: absolute;
  background-color: rgba(82, 82, 82, 0.75);
  top: 0;
  left: 0;
}

.modal-form {
  position: absolute;
  background-color: #eee3cb;

  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  padding: 30px;

  display: flex;
  flex-direction: column;
  align-items: center;
  row-gap: 30px;
}

.high-num-label {
  font-size: 2.4rem;
  text-align: center;
}

.high-num-input {
  padding-left: 0.5rem;
  font-size: 3.2rem;
  width: 30%;
  border: 1px solid black;
}

.submit-btn {
  font-size: 4.2rem;
  padding: 1rem 2rem;
}

.hide {
  display: none;
}

.starting-msg {
  font-size: 4.4rem;
  text-align: center;
  width: 100%;
  margin: 0 auto;
}

.right-answer {
  background-color: #8ce99a;
}

.wrong-answer {
  background-color: red;
}

@media (max-width: 64em) {
  .submit-btn {
    font-size: 2.8rem;
  }
  .num {
    font-size: 7rem;
    min-width: 12rem;
    height: 12rem;
  }
  .time-points {
    font-size: 2.4rem;
  }
  .starting-msg {
    font-size: 3rem;
  }
}
@media (max-width: 48em) {
  .modal-form {
    padding: 1rem;
  }
  .submit-btn {
    font-size: 1.8rem;
    padding: 0.5rem 1rem;
  }
  .high-num-input {
    font-size: 2.4rem;
  }
  .high-num-label {
    font-size: 1.8rem;
  }

  .num {
    font-size: 4rem;
    min-width: 6rem;
    height: 6rem;
  }
  .sign {
    font-size: 4rem;
    width: 5rem;
    height: 5rem;
  }
  .time-points {
    font-size: 1.8rem;
  }
}
@media (max-width: 30em) {
  .modal-form {
    padding: 1rem;
  }
  .submit-btn {
    font-size: 1.8rem;
    padding: 0.5rem 1rem;
  }
  .high-num-input {
    font-size: 2.4rem;
  }
  .high-num-label {
    font-size: 1.8rem;
  }
  .time-points {
    flex-direction: column;
    row-gap: 0.5rem;
  }

  .num {
    font-size: 2.4rem;
    min-width: 3rem;
    height: 3rem;
  }
  .sign {
    font-size: 2.4rem;
    width: 3rem;
    height: 3rem;
  }
  .equation {
    justify-content: center;
    gap: 0.5rem;
  }
  .starting-msg {
    font-size: 2rem;
  }
}