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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #121212;
  color: #e5e5e5;
  line-height: 1.5;
}

.container {
  max-width: 600px;
  margin: 0 auto;
  padding: 16px;
}

header {
  text-align: center;
  margin-bottom: 24px;
}

header h1 {
  font-size: 28px;
  color: #60a5fa;
}

.card {
  background: #1e1e1e;
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 20px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.card h2 {
  font-size: 18px;
  margin-bottom: 16px;
  color: #f3f4f6;
}

.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 6px;
  color: #d1d5db;
}

input[type="text"],
input[type="number"] {
  width: 100%;
  padding: 12px;
  font-size: 16px;
  background: #2a2a2a;
  color: #e5e5e5;
  border: 1px solid #404040;
  border-radius: 8px;
  outline: none;
  transition: border-color 0.2s;
}

input:focus {
  border-color: #60a5fa;
}

.btn {
  display: inline-block;
  padding: 12px 20px;
  font-size: 16px;
  font-weight: 500;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-primary {
  background: #3b82f6;
  color: white;
  width: 100%;
  margin-top: 16px;
}

.btn-primary:hover {
  background: #60a5fa;
}

.btn-secondary {
  background: #404040;
  color: #e5e5e5;
  width: 100%;
  margin-bottom: 8px;
}

.btn-secondary:hover {
  background: #525252;
}

.exercise-form {
  background: #2a2a2a;
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 12px;
}

.exercise-header {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.exercise-name {
  flex: 1;
}

.btn-remove-exercise,
.btn-remove-property {
  background: #7f1d1d;
  color: #fca5a5;
  border: none;
  border-radius: 6px;
  width: 40px;
  height: 40px;
  font-size: 20px;
  cursor: pointer;
}

.btn-remove-exercise:hover,
.btn-remove-property:hover {
  background: #991b1b;
}

.properties-container {
  margin-bottom: 8px;
}

.property-row {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
}

.property-key {
  flex: 1;
  min-width: 150px;
}

.property-value {
  width: 120px;
  min-width: 100px;
}

.btn-add-property {
  background: transparent;
  border: 1px dashed #525252;
  color: #a3a3a3;
  padding: 8px 12px;
  font-size: 14px;
  border-radius: 6px;
  cursor: pointer;
  width: 100%;
}

.btn-add-property:hover {
  border-color: #737373;
  color: #d1d5db;
}

.session-item {
  border-bottom: 1px solid #404040;
  padding: 16px 0;
}

.session-item:last-child {
  border-bottom: none;
}

.session-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.session-info {
  flex: 1;
}

.session-date {
  font-weight: 600;
  color: #f3f4f6;
  display: block;
}

.session-notes {
  font-size: 14px;
  color: #a3a3a3;
}

.session-actions {
  display: flex;
  gap: 8px;
}

.btn-toggle,
.btn-delete {
  padding: 8px 12px;
  font-size: 14px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

.btn-toggle {
  background: #404040;
  color: #e5e5e5;
}

.btn-toggle:hover {
  background: #525252;
}

.btn-delete {
  background: #7f1d1d;
  color: #fca5a5;
}

.btn-delete:hover {
  background: #991b1b;
}

.session-details {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid #404040;
}

.session-details.hidden {
  display: none;
}

.exercise-item {
  background: #2a2a2a;
  border-radius: 8px;
  padding: 12px;
  margin-bottom: 8px;
}

.exercise-item h4 {
  font-size: 16px;
  color: #f3f4f6;
  margin-bottom: 8px;
}

.exercise-item .property {
  font-size: 14px;
  color: #d1d5db;
}

.exercise-item .property span {
  font-weight: 500;
}

.empty-state {
  text-align: center;
  padding: 32px;
  color: #737373;
}