:root {
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --accent: #3b82f6;
  --accent-light: #eff6ff;
  --accent-hover: #2563eb;
  --text: #1e293b;
  --text-muted: #64748b;
  --success: #10b981;
  --error: #ef4444;
  --border-color: #e2e8f0;
  --border-radius: 12px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: var(--bg-color);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.6;
}

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

.card {
  background: var(--card-bg);
  border-radius: var(--border-radius);
  padding: 32px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-md);
  transition: box-shadow 0.3s ease;
}

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

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 8px;
}

select,
input[type="text"],
input[type="password"],
input[type="email"],
input[type="number"] {
  width: 100%;
  padding: 12px 16px;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  color: var(--text);
  font-size: 1rem;
  transition: all 0.2s;
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  background-image: none;
}

select:focus,
input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.btn {
  padding: 14px 28px;
  border: none;
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--accent);
  color: white;
  width: 100%;
}

.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--accent-light);
  color: var(--accent);
}

.btn-secondary:hover {
  background: rgba(59, 130, 246, 0.2);
}

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

.btn-danger:hover {
  background: #dc2626;
}

.status {
  padding: 14px 18px;
  border-radius: var(--border-radius);
  margin-top: 20px;
  font-size: 0.95rem;
  text-align: center;
}

.status.info {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  color: var(--accent);
}

.status.success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.2);
  color: var(--success);
}

.status.error {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.2);
  color: var(--error);
}

.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--card-bg);
  border-radius: var(--border-radius);
  padding: 30px;
  max-width: 500px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 15px;
}

.modal-header h3 {
  font-size: 1.3rem;
  font-weight: 600;
}

.close-btn {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-muted);
}

.info-item {
  display: flex;
  justify-content: space-between;
  padding: 12px 0;
  border-bottom: 1px solid var(--border-color);
}

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

.label {
  color: var(--text-muted);
  font-weight: 500;
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-color);
}

.nav-links {
  display: flex;
  gap: 15px;
}

.nav a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 8px;
  transition: background 0.2s;
}

.nav a:hover {
  background: var(--accent-light);
  color: var(--accent);
}

.user-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.balance {
  background: var(--accent-light);
  color: var(--accent);
  padding: 6px 12px;
  border-radius: 20px;
  font-weight: 600;
  font-size: 0.9rem;
}

/* 双端适配 */
@media (max-width: 600px) {
  body {
    padding: 20px 16px;
  }
  
  .card {
    padding: 24px 20px;
  }
  
  .btn {
    padding: 16px 24px;
    font-size: 1.05rem;
  }
  
  .nav {
    flex-direction: column;
    gap: 10px;
  }
  
  .nav-links {
    width: 100%;
    justify-content: center;
  }
}