:root {
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-danger: #ef4444;
  --color-danger-hover: #dc2626;
  --color-success: #22c55e;
  --color-warning: #f59e0b;
  --color-neutral-50: #fafafa;
  --color-neutral-100: #f5f5f5;
  --color-neutral-200: #e5e5e5;
  --color-neutral-300: #d4d4d4;
  --color-neutral-500: #737373;
  --color-neutral-700: #404040;
  --color-neutral-900: #171717;
  --bg-body: #f5f5f5;
  --bg-card: #ffffff;
  --bg-input: #ffffff;
  --bg-card-footer: #fafafa;
  --text-primary: #171717;
  --text-secondary: #404040;
  --text-muted: #737373;
  --border-color: #e5e5e5;
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --border-radius-sm: 0.25rem;
  --border-radius-md: 0.5rem;
  --border-radius-lg: 0.75rem;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #60a5fa;
    --color-primary-hover: #3b82f6;
    --color-danger: #f87171;
    --color-danger-hover: #ef4444;
    --color-success: #4ade80;
    --color-warning: #fbbf24;
    --color-neutral-50: #262626;
    --color-neutral-100: #171717;
    --color-neutral-200: #404040;
    --color-neutral-300: #525252;
    --color-neutral-500: #a3a3a3;
    --color-neutral-700: #d4d4d4;
    --color-neutral-900: #fafafa;
    --bg-body: #0a0a0a;
    --bg-card: #171717;
    --bg-input: #262626;
    --bg-card-footer: #0a0a0a;
    --text-primary: #fafafa;
    --text-secondary: #d4d4d4;
    --text-muted: #a3a3a3;
    --border-color: #404040;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.5);
  }
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-body);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

.container {
  max-width: 640px;
  margin: 0 auto;
  padding: var(--spacing-lg);
}

.card {
  background: var(--bg-card);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-lg);
  overflow: hidden;
}

.card-header {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--border-color);
}

.card-header h1,
.card-header h2,
.card-header h3 {
  margin: 0;
  font-weight: 600;
}

.card-header h1 {
  font-size: 1.5rem;
}

.card-header h2 {
  font-size: 1.25rem;
}

.card-header h3 {
  font-size: 1.1rem;
}

.card-body {
  padding: var(--spacing-lg);
}

.card-footer {
  padding: var(--spacing-lg);
  border-top: 1px solid var(--border-color);
  background: var(--bg-card-footer);
}

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-group:last-child {
  margin-bottom: 0;
}

.form-group label {
  display: block;
  font-weight: 500;
  margin-bottom: var(--spacing-xs);
  color: var(--text-secondary);
}

.form-group label .required {
  color: var(--color-danger);
  margin-left: var(--spacing-xs);
}

.form-group .helper-text {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: var(--spacing-xs);
}

input[type="text"],
input[type="email"],
input[type="password"],
textarea {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  font-size: 1rem;
  background-color: var(--bg-input);
  color: var(--text-primary);
  transition: border-color 0.2s, box-shadow 0.2s;
}

input:focus,
textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgb(59 130 246 / 0.1);
}

textarea {
  resize: vertical;
  min-height: 80px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  border: none;
  border-radius: var(--border-radius-md);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
}

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

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--color-primary-hover);
}

.btn-secondary {
  background-color: var(--color-neutral-200);
  color: var(--text-primary);
}

.btn-secondary:hover:not(:disabled) {
  background-color: var(--color-neutral-300);
}

.btn-danger {
  background-color: var(--color-danger);
  color: white;
}

.btn-danger:hover:not(:disabled) {
  background-color: var(--color-danger-hover);
}

.btn-outline {
  background-color: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
}

.btn-outline:hover:not(:disabled) {
  background-color: var(--color-neutral-50);
}

.btn-full {
  width: 100%;
}

.btn-group {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: flex-end;
}

.header-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.event-detail {
  display: flex;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
}

.event-detail .label {
  font-weight: 500;
  color: var(--text-muted);
  min-width: 60px;
}

.event-detail .value {
  color: var(--text-primary);
}

.event-description {
  white-space: pre-wrap;
  color: var(--text-secondary);
}

.participant-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.participant-item {
  display: flex;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  background: var(--color-neutral-50);
  border-radius: var(--border-radius-md);
}

.participant-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 1.1rem;
  flex-shrink: 0;
}

.participant-info {
  flex: 1;
  min-width: 0;
}

.participant-name {
  font-weight: 500;
  margin-bottom: var(--spacing-xs);
}

.participant-comment {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: var(--spacing-xs);
}

.participant-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.participant-actions {
  flex-shrink: 0;
}

.count-badge {
  background: var(--color-primary);
  color: white;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
}

.empty-state {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--text-muted);
}

.alert {
  padding: var(--spacing-md);
  border-radius: var(--border-radius-md);
  margin-bottom: var(--spacing-md);
}

.alert-success {
  background: #dcfce7;
  color: #166534;
  border: 1px solid #86efac;
}

.alert-error {
  background: #fee2e2;
  color: #991b1b;
  border: 1px solid #fca5a5;
}

.alert-info {
  background: #dbeafe;
  color: #1e40af;
  border: 1px solid #93c5fd;
}

.hidden {
  display: none !important;
}

.loading {
  opacity: 0.6;
  pointer-events: none;
}

@media (max-width: 640px) {
  .container {
    padding: var(--spacing-md);
  }

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

  .btn-group .btn {
    width: 100%;
  }
}