:root {
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --primary-light: #818cf8;
  --secondary: #64748b;
  --success: #10b981;
  --success-bg: #d1fae5;
  --warning: #f59e0b;
  --warning-bg: #fef3c7;
  --error: #ef4444;
  --error-bg: #fee2e2;
  --info: #3b82f6;
  --info-bg: #dbeafe;

  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --bg-card: #ffffff;
  --bg-hover: #f1f5f9;

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;

  --border-color: #e2e8f0;
  --border-radius: 12px;
  --border-radius-sm: 8px;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);

  --transition: all 0.2s ease;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
}

[data-theme="dark"] {
  --primary: #818cf8;
  --primary-hover: #6366f1;
  --primary-light: #a5b4fc;

  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-card: #1e293b;
  --bg-hover: #334155;

  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #64748b;

  --border-color: #334155;

  --success-bg: #064e3b;
  --warning-bg: #78350f;
  --error-bg: #7f1d1d;
  --info-bg: #1e3a8a;
}

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

body {
  font-family: var(--font-family);
  background: var(--bg-secondary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

.app-container {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Header */
.app-header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo i {
  font-size: 1.75rem;
  color: var(--primary);
}

.logo h1 {
  font-size: 1.25rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-actions {
  display: flex;
  gap: 0.5rem;
}

/* Main Content */
.main-content {
  display: flex;
  flex: 1;
}

/* Sidebar */
.sidebar {
  width: 220px;
  background: var(--bg-card);
  border-right: 1px solid var(--border-color);
  padding: 1rem 0;
  flex-shrink: 0;
}

.nav-menu {
  list-style: none;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1.5rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
  border-left: 3px solid transparent;
}

.nav-item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.nav-item.active {
  background: var(--bg-hover);
  color: var(--primary);
  border-left-color: var(--primary);
  font-weight: 500;
}

.nav-item i {
  width: 20px;
  text-align: center;
}

/* Content Area */
.content-area {
  flex: 1;
  padding: 1.5rem;
  overflow-y: auto;
  max-width: 1200px;
}

/* Cards */
.card {
  background: var(--bg-card);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  background: var(--bg-tertiary);
  border-radius: var(--border-radius) var(--border-radius) 0 0;
}

.card-header h2 {
  font-size: 1rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card-header h2 i {
  color: var(--primary);
}

.header-buttons {
  display: flex;
  gap: 0.5rem;
}

.card-body {
  padding: 1.5rem;
}

/* Forms */
.form-row {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.form-group.flex-grow {
  flex: 1;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.form-control {
  padding: 0.625rem 0.875rem;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  font-size: 0.875rem;
  background: var(--bg-primary);
  color: var(--text-primary);
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-control::placeholder {
  color: var(--text-muted);
}

textarea.form-control {
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}

select.form-control {
  cursor: pointer;
}

.password-input {
  position: relative;
  display: flex;
}

.password-input .form-control {
  flex: 1;
  padding-right: 2.5rem;
}

.btn-toggle-password {
  position: absolute;
  right: 0.5rem;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.25rem;
}

.btn-toggle-password:hover {
  color: var(--text-primary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border: none;
  border-radius: var(--border-radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

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

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

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-hover);
}

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

.btn-outline:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  color: var(--text-secondary);
}

.btn-icon:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.btn-sm {
  padding: 0.375rem 0.75rem;
  font-size: 0.8125rem;
}

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

.action-bar {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
}

/* Tab Content */
.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* Inline Tabs */
.tabs-inline {
  display: flex;
  gap: 0.25rem;
  margin-bottom: 0.5rem;
}

.tab-btn {
  padding: 0.375rem 0.75rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
}

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

/* Custom Headers */
.header-row {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.header-row .header-name {
  width: 200px;
}

.header-row .header-value {
  flex: 1;
}

.btn-remove-header {
  width: 36px;
  height: 36px;
  padding: 0;
  background: var(--error-bg);
  border: none;
  border-radius: var(--border-radius-sm);
  color: var(--error);
  cursor: pointer;
}

/* Results */
.overall-score {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.score-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.score-value {
  font-size: 1.25rem;
  font-weight: 700;
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  background: var(--success-bg);
  color: var(--success);
}

.score-value.warning {
  background: var(--warning-bg);
  color: var(--warning);
}

.score-value.error {
  background: var(--error-bg);
  color: var(--error);
}

/* Diagnostic Check */
.diagnostic-check {
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  margin-bottom: 1rem;
  overflow: hidden;
}

.check-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  background: var(--bg-tertiary);
  cursor: pointer;
  transition: var(--transition);
}

.check-header:hover {
  background: var(--bg-hover);
}

.check-title {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 500;
}

.check-title-text {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.check-description {
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--text-muted);
}

.check-status {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
}

.status-badge {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.625rem;
  border-radius: 20px;
  font-weight: 500;
}

.status-badge.success {
  background: var(--success-bg);
  color: var(--success);
}

.status-badge.warning {
  background: var(--warning-bg);
  color: var(--warning);
}

.status-badge.error {
  background: var(--error-bg);
  color: var(--error);
}

.status-badge.checking {
  background: var(--info-bg);
  color: var(--info);
}

.check-score {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.check-body {
  padding: 1rem;
  border-top: 1px solid var(--border-color);
  display: none;
}

.check-body.expanded {
  display: block;
}

.check-messages {
  list-style: none;
}

.check-message {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 0.5rem 0;
  font-size: 0.875rem;
  border-bottom: 1px solid var(--border-color);
}

.check-message:last-child {
  border-bottom: none;
}

.check-message i {
  margin-top: 0.125rem;
}

.check-message.success i {
  color: var(--success);
}

.check-message.warning i {
  color: var(--warning);
}

.check-message.error i {
  color: var(--error);
}

.check-message.info i {
  color: var(--info);
}

.check-message.debug i {
  color: var(--text-muted);
}

.check-details {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-color);
}

.check-details h4 {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.details-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0.75rem;
}

.detail-item {
  background: var(--bg-tertiary);
  padding: 0.75rem;
  border-radius: var(--border-radius-sm);
}

.detail-item .label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.detail-item .value {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  word-break: break-all;
  margin-top: 0.25rem;
}

/* Code Block */
.code-block {
  background: var(--bg-tertiary);
  padding: 1rem;
  border-radius: var(--border-radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-all;
}

/* History */
.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  margin-bottom: 0.75rem;
  cursor: pointer;
  transition: var(--transition);
}

.history-item:hover {
  background: var(--bg-hover);
}

.history-info {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.history-host {
  font-weight: 500;
}

.history-time {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.history-actions {
  display: flex;
  gap: 0.5rem;
}

.empty-state {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
}

.empty-state i {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  display: block;
}

/* Loading Overlay */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.loading-overlay.active {
  display: flex;
}

.loading-spinner {
  background: var(--bg-card);
  padding: 2rem 3rem;
  border-radius: var(--border-radius);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  box-shadow: var(--shadow-lg);
}

.loading-spinner i {
  font-size: 2.5rem;
  color: var(--primary);
}

/* Alert */
.alert {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-radius: var(--border-radius-sm);
  margin-bottom: 1rem;
  font-size: 0.875rem;
}

.alert i {
  font-size: 1rem;
  flex-shrink: 0;
}

.alert a {
  color: inherit;
  font-weight: 500;
}

.alert-info {
  background: var(--info-bg);
  color: var(--info);
  border: 1px solid var(--info);
}

.alert-warning {
  background: var(--warning-bg);
  color: #92400e;
  border: 1px solid var(--warning);
}

.alert-success {
  background: var(--success-bg);
  color: #065f46;
  border: 1px solid var(--success);
}

.alert-error {
  background: var(--error-bg);
  color: #991b1b;
  border: 1px solid var(--error);
}

[data-theme="dark"] .alert-info {
  background: rgba(59, 130, 246, 0.15);
  color: #93c5fd;
}

[data-theme="dark"] .alert-warning {
  background: rgba(245, 158, 11, 0.15);
  color: #fcd34d;
}

[data-theme="dark"] .alert-success {
  background: rgba(16, 185, 129, 0.15);
  color: #6ee7b7;
}

[data-theme="dark"] .alert-error {
  background: rgba(239, 68, 68, 0.15);
  color: #fca5a5;
}

/* Toast */
.toast-container {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  z-index: 1001;
}

.toast {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-card);
  border-radius: var(--border-radius-sm);
  box-shadow: var(--shadow-lg);
  animation: slideIn 0.3s ease;
  min-width: 300px;
  border-left: 4px solid var(--primary);
}

.toast.success {
  border-left-color: var(--success);
}

.toast.error {
  border-left-color: var(--error);
}

.toast.warning {
  border-left-color: var(--warning);
}

.toast i {
  font-size: 1.25rem;
}

.toast.success i {
  color: var(--success);
}

.toast.error i {
  color: var(--error);
}

.toast.warning i {
  color: var(--warning);
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

/* DNS Records */
.dns-record-group {
  margin-bottom: 1.5rem;
}

.dns-record-group h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.dns-record {
  background: var(--bg-tertiary);
  padding: 0.75rem 1rem;
  border-radius: var(--border-radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  margin-bottom: 0.5rem;
}

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    display: none;
  }

  .form-row {
    flex-direction: column;
  }

  .form-control {
    width: 100% !important;
  }
}