:root {
  --primary-bg: linear-gradient(to bottom, #f8fafc, #f1f5f9);
  --card-bg: #ffffff;
  --card-hover-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --border-color: #e2e8f0;
  --primary-color: #6366f1;
  --primary-hover: #4f46e5;
  --success-color: #10b981;
  --success-bg: #ecfdf5;
  --error-color: #ef4444;
  --error-bg: #fef2f2;
  --option-hover: #f8fafc;
  --option-active: #eff6ff;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--primary-bg);
  color: var(--text-primary);
  line-height: 1.5;
  padding: 2rem 1rem;
  min-height: 100vh;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  /*align-items: center;*/
  /*justify-content: center;*/
  min-height: calc(100vh - 4rem);
}

.quiz-container {
  width: 100%;
  max-width: 800px;
}

h1 {
  text-align: center;
  margin-bottom: 0.5rem;
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
}

h2 {
  text-align: center;
  margin-bottom: 0.2rem;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-primary);
}

h3 {
  text-align: center;
  margin-bottom: 0.2rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.card {
  background-color: var(--card-bg);
  border-radius: 0.75rem;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: box-shadow 0.3s ease, transform 0.3s ease;
  padding: 2rem;
  margin-bottom: 1.5rem;
  min-height: 300px;
  display: flex;
  flex-direction: column;
}

.card:hover {
  box-shadow: var(--card-hover-shadow);
}

.question {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

.options {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.option {
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
}

.option:hover {
  background-color: var(--option-hover);
}

.option.selected {
  background-color: var(--option-active);
  border-color: var(--primary-color);
}

.feedback {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 1.5rem;
}

.feedback.correct {
  background-color: var(--success-bg);
  color: var(--success-color);
  border-radius: 0.5rem;
}

.feedback.incorrect {
  background-color: var(--error-bg);
  color: var(--error-color);
  border-radius: 0.5rem;
}

.feedback-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.feedback-message {
  color: var(--text-primary);
  margin-bottom: 1.5rem;
}

.button{
  background-color: var(--primary-color);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s ease;
  margin-top: auto;
  align-self: center;
}

.button:hover {
  background-color: var(--primary-hover);
}

.progress-container {
  width: 100%;
  margin-top: 1rem;
}

#progress-text {
  text-align: center;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.progress-bar {
  width: 100%;
  height: 0.5rem;
  background-color: var(--border-color);
  border-radius: 9999px;
  overflow: hidden;
}

#progress-fill {
  height: 100%;
  background-color: var(--primary-color);
  border-radius: 9999px;
  transition: width 0.3s ease;
}

.loader {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 200px;
  color: var(--text-secondary);
}

.result-summary {
  text-align: center;
  margin-bottom: 2rem;
}

.score {
  font-size: 3rem;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.restart-button {
  background-color: var(--primary-color);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.restart-button:hover {
  background-color: var(--primary-hover);
}

@media (max-width: 640px) {
  .card {
    padding: 1.5rem;
    min-height: 250px;
  }

  .question {
    font-size: 1.125rem;
  }

  .option {
    padding: 0.75rem;
  }
}