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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  background: white;
  border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  overflow: hidden;
}

header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 30px;
  text-align: center;
}

h1 {
  font-size: 2rem;
  margin-bottom: 8px;
}

.subtitle {
  opacity: 0.9;
  font-size: 0.95rem;
}

main {
  padding: 30px;
}

.section {
  margin-bottom: 30px;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
}

h2 {
  color: #333;
  font-size: 1.3rem;
}

.info-text {
  color: #666;
  font-size: 0.9rem;
  margin-bottom: 10px;
  font-style: italic;
}

.subjects-container {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.subject-row {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 12px;
  background: #f8f9fa;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
}

.subject-row select {
  flex: 1;
  padding: 8px 12px;
  border: 1px solid #ddd;
  border-radius: 6px;
  font-size: 0.95rem;
  background: white;
  cursor: pointer;
}

.checkbox-container {
  display: flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.checkbox-container input[type="checkbox"] {
  width: 18px;
  height: 18px;
  cursor: pointer;
}

.btn-remove {
  background: #dc3545;
  color: white;
  border: none;
  padding: 8px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.2s;
}

.btn-remove:hover {
  background: #c82333;
}

.btn-add {
  background: #667eea;
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.2s;
}

.btn-add:hover {
  background: #5568d3;
}

.weighting-section {
  background: #f0f4ff;
  padding: 20px;
  border-radius: 8px;
}

.slider-container {
  display: flex;
  align-items: center;
  gap: 15px;
  margin-top: 15px;
}

.slider-container label {
  font-weight: 600;
  color: #555;
  min-width: 100px;
}

#weight-slider {
  flex: 1;
  height: 6px;
  border-radius: 3px;
  outline: none;
  -webkit-appearance: none;
  background: linear-gradient(to right, #667eea 0%, #764ba2 100%);
}

#weight-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: #667eea;
  cursor: pointer;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

#weight-slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: #667eea;
  cursor: pointer;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
  border: none;
}

.target-section input {
  width: 100%;
  padding: 12px;
  border: 1px solid #ddd;
  border-radius: 6px;
  font-size: 1rem;
  margin-top: 10px;
}

.button-group {
  display: flex;
  gap: 15px;
  margin-top: 30px;
}

.btn-primary,
.btn-secondary {
  flex: 1;
  padding: 15px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
  background: #28a745;
  color: white;
}

.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(40, 167, 69, 0.4);
}

.result {
  margin-top: 30px;
  padding: 20px;
  border-radius: 8px;
  display: none;
}

.result.show {
  display: block;
}

.result.success {
  background: #d4edda;
  border: 1px solid #c3e6cb;
  color: #155724;
}

.result.error {
  background: #f8d7da;
  border: 1px solid #f5c6cb;
  color: #721c24;
}

.result h3 {
  margin-bottom: 15px;
  font-size: 1.2rem;
}

.result-details {
  margin-top: 10px;
  line-height: 1.8;
}

.prediction-item {
  margin: 8px 0;
  padding: 8px;
  background: rgba(255, 255, 255, 0.5);
  border-radius: 4px;
}

.combination-rank {
  margin: 8px 0;
  padding: 10px;
  background: rgba(255, 255, 255, 0.5);
  border-radius: 6px;
  border-left: 3px solid #667eea;
  font-family: monospace;
  font-size: 0.95rem;
}

.combination-rank strong {
  color: #667eea;
  margin-right: 8px;
}

@media (max-width: 768px) {
  .subject-row {
    flex-wrap: wrap;
  }

  .button-group {
    flex-direction: column;
  }

  .slider-container {
    flex-direction: column;
    align-items: stretch;
  }
}