body {
  font-family: Arial, sans-serif;
  background: linear-gradient(135deg, #99f5c4, #eef2f3);
  margin: 0;
  padding: 25px;
}

.container {
  max-width: 900px;
  margin: auto;
  background: #ffffff;
  padding: 30px;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.12);
}

h1 {
  text-align: center;
  font-size: 60px;
  color: rgb(60, 60, 60);
  margin-bottom: 25px;
  letter-spacing: 0.5px;
}

.question {
  margin-bottom: 22px;
  padding: 18px;
  border-radius: 10px;
  background: #f7f9fb;
  border: 1px solid #e3e7ec;
  transition: 0.2s ease;
}

.question:hover {
  background: #f1f5f9;
  transform: translateY(-2px);
}

p {
  font-size: 18;
}

label {
  display: block;
  padding: 10px 12px;
  margin: 6px 0;
  background: #ffffff;
  border: 1px solid #e3e7ec;
  border-radius: 8px;
  cursor: pointer;
  transition: 0.2s ease;
  font-size: 18px;
}

label:hover {
  background: #f1f1f1;
  border-color: #cfd6df;
}

input[type="checkbox"] {
  margin-right: 10px;
  transform: scale(1.05);
}

.btn {
  display: block;
  margin: 20px auto;
  padding: 20px 30px;
  background: #2c3e50;
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 22px;
  cursor: pointer;
  font-weight: bold;
  transition: 0.2s ease;
  box-shadow: 0 6px 15px rgba(0, 0, 0, 0.15);
}

.btn:hover {
  background: #1f2d3d;
  transform: translateY(-2px);
}

.btn:active {
  transform: scale(0.98);
}

.correct {
  background: #e6fde1 !important;
  border-color: #bcdcc9 !important;
}

.wrong {
  background: #fde1e1 !important;
  border-color: #f5bcbc !important;
}

input:disabled {
  opacity: 0.7;
  cursor: not-allowed;
}

#result {
  text-align: center;
  font-size: 18px;
  margin-top: 20px;
  font-weight: bold;
  color: #1f2d3d;
  white-space: pre-line;
}

#timer {
  font-size: 26px;
  text-align: center;
  margin-bottom: 30px;
  font-weight: bold;
  color: #535c66;
}

/* Mobile Responsive Styles */
@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  .container {
    padding: 15px;
    border-radius: 10px;
  }

  h1 {
    font-size: 36px;
    margin-bottom: 15px;
  }

  #timer {
    font-size: 16px;
    text-align: center;
    margin-bottom: 15px;
    font-weight: bold;
  }

  .question {
    margin-bottom: 15px;
    padding: 12px;
    border-radius: 8px;
  }

  label {
    padding: 8px 10px;
    margin: 4px 0;
    font-size: 14px;
  }

  .btn {
    padding: 15px 20px;
    font-size: 16px;
    margin: 15px auto;
    width: 90%;
    max-width: 300px;
  }

  p {
    font-size: 14px;
  }
}

@media (max-width: 480px) {
  body {
    padding: 8px;
  }

  .container {
    padding: 12px;
    max-width: 100%;
  }

  h1 {
    font-size: 28px;
    margin-bottom: 10px;
  }

  #timer {
    font-size: 14px;
    margin-bottom: 12px;
  }

  .question {
    margin-bottom: 12px;
    padding: 10px;
  }

  label {
    padding: 8px;
    margin: 3px 0;
    font-size: 13px;
  }

  input[type="checkbox"] {
    margin-right: 8px;
  }

  .btn {
    padding: 12px 15px;
    font-size: 14px;
    margin: 12px auto;
    width: 95%;
  }

  p {
    font-size: 12px;
  }
}