/*
 * InfoAir PWA - Mobile-First Cross-Platform Styles
 * Optimized for iOS (Safari/WebKit) and Android (Chrome/WebView)
 * Target screens: 360px-428px (mobile), 768px+ (tablet)
 */

/* ============================================
   CSS VARIABLES & THEME
   ============================================ */
:root {
  /* Colors - Palette */
  --primary-color: #007bff;
  --primary-dark: #0056b3;
  --primary-light: #cce5ff;

  --secondary-color: #6c757d;
  --secondary-dark: #545b62;
  --secondary-light: #e2e3e5;

  --success-color: #28a745;
  --success-dark: #1e7e34;
  --success-light: #d4edda;

  --danger-color: #dc3545;
  --danger-dark: #bd2130;
  --danger-light: #f8d7da;

  --warning-color: #ffc107;
  --warning-dark: #e0a800;
  --warning-light: #fff3cd;

  --info-color: #17a2b8;
  --info-light: #d1ecf1;

  /* Neutrals */
  --gray-50: #f9fafb;
  --gray-100: #f8f9fa;
  --gray-200: #e9ecef;
  --gray-300: #dee2e6;
  --gray-400: #ced4da;
  --gray-500: #adb5bd;
  --gray-600: #6c757d;
  --gray-700: #495057;
  --gray-800: #343a40;
  --gray-900: #212529;

  --bg-color: #f4f4f4;
  --card-bg: #ffffff;
  --text-color: #212529;
  --text-secondary: #6c757d;
  --border-color: #dee2e6;

  /* State Colors */
  --state-normal: #28a745;
  --state-heating: #007bff;
  --state-cooling: #ffc107;
  --state-alarm: #dc3545;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;

  /* Borders */
  --border-radius: 12px;
  --border-radius-sm: 8px;
  --border-radius-lg: 16px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, monospace;
  --line-height: 1.5;
  --line-height-heading: 1.3;

  /* Transitions */
  --transition-fast: 0.15s ease-in-out;
  --transition-base: 0.2s ease-in-out;
  --transition-slow: 0.3s ease-in-out;

  /* Touch Targets (iOS HIG: 44pt min, Android: 48dp min) */
  --touch-target-min: 44px;

  /* Safe Areas (iOS notch, Dynamic Island) */
  --safe-area-top: env(safe-area-inset-top, 0px);
  --safe-area-right: env(safe-area-inset-right, 0px);
  --safe-area-bottom: env(safe-area-inset-bottom, 0px);
  --safe-area-left: env(safe-area-inset-left, 0px);

  /* Bottom Navigation Height */
  --bottom-nav-height: 60px;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  /* Prevent iOS text size adjust after orientation change */
  -webkit-text-size-adjust: 100%;
  /* Smooth scrolling (where supported) */
  scroll-behavior: smooth;
  /* Fix for iOS viewport height (100vh issue with address bar) */
  height: 100%;
}

body {
  font-family: var(--font-family);
  font-size: 16px; /* Base 16px for accessibility */
  line-height: var(--line-height);
  color: var(--text-color);
  background-color: var(--bg-color);

  /* Prevent text selection (app-like feel) */
  -webkit-user-select: none;
  user-select: none;

  /* Prevent tap highlight on iOS */
  -webkit-tap-highlight-color: transparent;

  /* Prevent overscroll bounce on iOS */
  overscroll-behavior-y: none;

  /* Fix for iOS viewport height */
  min-height: 100vh;
  min-height: -webkit-fill-available;
}

/* Allow text selection in inputs/textareas */
input,
textarea {
  -webkit-user-select: text;
  user-select: text;
}

/* ============================================
   APP LAYOUT
   ============================================ */
#app {
  display: flex;
  flex-direction: column;
  height: 100vh;
  height: -webkit-fill-available; /* iOS Safari fix */
  min-height: 100vh; /* Fallback */
}

.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--primary-color);
  color: white;
  box-shadow: var(--shadow-md);

  /* Safe area for iOS notch */
  padding-top: var(--safe-area-top);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md);
  min-height: var(--touch-target-min);
}

.header-left {
  display: flex;
  align-items: baseline;
  gap: var(--spacing-sm);
}

.app-title {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: var(--line-height-heading);
  margin: 0;
}

.version-badge {
  font-size: 0.75rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.8);
  background-color: rgba(255, 255, 255, 0.2);
  padding: 2px 8px;
  border-radius: 12px;
  font-family: var(--font-mono);
  white-space: nowrap;
}

.connection-status {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 0.875rem;
}

.btn-disconnect {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  padding: 0;
  margin-left: var(--spacing-xs);
  background-color: rgba(255, 255, 255, 0.15);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  cursor: pointer;
  transition: all var(--transition-fast);
  min-width: var(--touch-target-min);
  min-height: var(--touch-target-min);
  position: relative;
}

.btn-disconnect::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  border-radius: 50%;
}

.btn-disconnect:hover {
  background-color: rgba(255, 255, 255, 0.25);
  border-color: rgba(255, 255, 255, 0.5);
}

.btn-disconnect:active {
  background-color: rgba(255, 255, 255, 0.35);
  transform: scale(0.95);
}

.disconnect-icon {
  font-size: 1.25rem;
  line-height: 1;
  font-weight: 700;
}

.status-indicator {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--gray-500);
  transition: background-color var(--transition-base);
}

.status-indicator.connected {
  background-color: var(--success-color);
  box-shadow: 0 0 8px rgba(40, 167, 69, 0.6);
}

.status-indicator.connecting {
  background-color: var(--warning-color);
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.app-main {
  flex: 1;
  padding: var(--spacing-md);
  padding-bottom: calc(var(--bottom-nav-height) + var(--spacing-md) + var(--safe-area-bottom));
  overflow-y: auto;

  /* iOS momentum scrolling */
  -webkit-overflow-scrolling: touch;
}

/* CRITICAL FIX: Make app-main a flex container when chart tab is active */
.app-main.chart-active {
  display: flex;
  flex-direction: column;
  overflow-y: hidden;
  margin: 0 !important;  /* Remove horizontal auto-margins that limit width */
  max-width: none !important;  /* Remove max-width to allow full viewport width */
  padding: 0;
  padding-bottom: 0;
}

/* Desktop: increase padding for better spacing */
@media (min-width: 1024px) {
  .app-main {
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
  }
}

/* Large desktop: even more padding */
@media (min-width: 1440px) {
  .app-main {
    padding-left: var(--spacing-xl);
    padding-right: var(--spacing-xl);
  }
}

/* ============================================
   SECTIONS & CARDS
   ============================================ */
.section {
  margin-bottom: var(--spacing-lg);
}

.section.hidden {
  display: none;
}

/* Consistent spacing between Dispositivo, Stato Macchina, and main content */
#device-info-section {
  margin-bottom: var(--spacing-md);
}

#status-section {
  margin-bottom: var(--spacing-lg);
}

.card {
  background-color: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.card-title {
  font-size: 1.125rem;
  font-weight: 600;
  line-height: var(--line-height-heading);
  margin-bottom: var(--spacing-md);
  color: var(--gray-800);
}

.card-admin {
  border: 2px solid var(--warning-color);
  background-color: var(--warning-light);
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);

  /* Touch target sizing */
  min-height: var(--touch-target-min);
  padding: 0 var(--spacing-md);

  font-family: var(--font-family);
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.5;
  text-align: center;
  text-decoration: none;
  white-space: nowrap;

  border: 1px solid transparent;
  border-radius: var(--border-radius-sm);
  cursor: pointer;

  transition: all var(--transition-base);

  /* Remove iOS default styling */
  -webkit-appearance: none;
  appearance: none;

  /* Prevent text selection */
  -webkit-user-select: none;
  user-select: none;
}

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

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

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

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

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

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

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

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

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

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

.btn-large {
  min-height: 56px;
  font-size: 1.125rem;
  width: 100%;
}

.btn-small {
  min-height: 36px;
  padding: 0 var(--spacing-sm);
  font-size: 0.875rem;
}

.btn-group {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

.btn-group .btn {
  flex: 1;
}

/* ============================================
   INPUTS & FORMS
   ============================================ */
.input,
.textarea {
  width: 100%;
  min-height: var(--touch-target-min);
  padding: var(--spacing-sm) var(--spacing-md);

  font-family: var(--font-family);
  font-size: 1rem;
  line-height: var(--line-height);
  color: var(--text-color);

  background-color: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-sm);

  transition: border-color var(--transition-base);

  /* Remove iOS default styling */
  -webkit-appearance: none;
  appearance: none;
}

.input:focus,
.textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.textarea {
  min-height: 120px;
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.input-mono {
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.textarea-mono {
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

/* ============================================
   STATE DISPLAY
   ============================================ */
.state-display {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  background-color: var(--gray-100);
  border-radius: var(--border-radius-sm);
  border-left: 4px solid var(--gray-500);
  transition: border-color var(--transition-base);

  /* Allow text selection */
  -webkit-user-select: text;
  user-select: text;
}

.state-display.state-normal {
  border-left-color: var(--state-normal);
  background-color: var(--success-light);
}

.state-display.state-heating {
  border-left-color: var(--state-heating);
  background-color: var(--primary-light);
}

.state-display.state-cooling {
  border-left-color: var(--state-cooling);
  background-color: var(--warning-light);
}

.state-display.state-alarm {
  border-left-color: var(--state-alarm);
  background-color: var(--danger-light);
}

.state-description {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--gray-900);
  line-height: 1.3;
}

.state-code {
  font-size: 0.75rem;
  font-weight: 500;
  font-family: var(--font-mono);
  color: var(--text-secondary);
  opacity: 0.7;
}

/* ============================================
   SENSOR GRID
   ============================================ */

/* Sensor section headers (ANALOG, INPUTS, OUTPUTS, LEDS) */
.sensor-section-header {
  grid-column: 1 / -1; /* Span all columns */
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: var(--spacing-sm) 0;
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-xs);
  border-bottom: 2px solid var(--border-color);
}

.sensor-section-header:first-child {
  margin-top: 0;
}

.sensor-grid {
  display: grid;
  /* FORCE 2 columns on mobile (no auto-fill) */
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
  margin-bottom: var(--spacing-md);
}

.sensor-card {
  background-color: var(--gray-100);
  border-radius: var(--border-radius-sm);
  padding: 12px;
  min-height: 100px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: background-color var(--transition-base), box-shadow var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.sensor-card:active {
  background-color: var(--gray-200);
}

.sensor-name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-xs);
  line-height: 1.2;
  /* Truncate long names with ellipsis */
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sensor-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-color);
  margin-bottom: var(--spacing-sm);
  line-height: 1.1;
  /* Allow value to wrap if needed */
  word-break: break-word;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Digital input/output color states */
.sensor-value.sensor-value-on {
  color: #10b981 !important; /* Green for ON state */
  font-weight: 800;
}

.sensor-value.sensor-value-off {
  color: #6b7280 !important; /* Gray for OFF state */
  font-weight: 600;
}

/* Flash animation when value changes (streaming) */
.sensor-value.sensor-flash {
  animation: flash 0.3s ease;
}

@keyframes flash {
  0% { background-color: transparent; }
  50% { background-color: rgba(0, 123, 255, 0.2); }
  100% { background-color: transparent; }
}

.sensor-unit {
  font-size: 0.9rem;
  font-weight: 400;
  color: var(--text-secondary);
  margin-left: var(--spacing-xs);
}

/* LED Indicator */
.sensor-led {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background-color: var(--gray-400);
  transition: background-color var(--transition-base), box-shadow var(--transition-base);
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.2);
  margin-top: auto; /* Push to bottom of flex container */
  align-self: center;
}

.sensor-led.on {
  background-color: var(--success-color);
  box-shadow: 0 0 10px rgba(40, 167, 69, 0.8), inset 0 1px 1px rgba(255, 255, 255, 0.3);
  animation: led-pulse 2s ease-in-out infinite;
}

.sensor-led.off {
  background-color: #6b7280; /* Gray for OFF state (same as text) */
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.3);
}

@keyframes led-pulse {
  0%, 100% {
    box-shadow: 0 0 10px rgba(40, 167, 69, 0.8), inset 0 1px 1px rgba(255, 255, 255, 0.3);
  }
  50% {
    box-shadow: 0 0 15px rgba(40, 167, 69, 1), inset 0 1px 1px rgba(255, 255, 255, 0.3);
  }
}

/* Progress Bar for Analog Sensors */
.sensor-progress {
  width: 100%;
  height: 8px;
  background-color: var(--gray-300);
  border-radius: 4px;
  overflow: hidden;
  margin-top: var(--spacing-sm);
}

.sensor-progress-bar {
  height: 100%;
  background-color: var(--primary-color);
  transition: width var(--transition-base);
  border-radius: 4px;
}

/* Toggle Switch for Outputs */
.toggle-switch {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 28px;
  margin-top: var(--spacing-sm);
  /* Ensure touch target is at least 44px */
  padding: 8px 0;
}

.toggle-switch input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 8px;
  left: 0;
  right: 0;
  bottom: 8px;
  height: 28px;
  background-color: var(--gray-400);
  transition: var(--transition-base);
  border-radius: 28px;
  /* iOS -webkit-appearance reset */
  -webkit-appearance: none;
  appearance: none;
}

.toggle-slider:before {
  position: absolute;
  content: "";
  height: 20px;
  width: 20px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  transition: var(--transition-base);
  border-radius: 50%;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.toggle-switch input:checked + .toggle-slider {
  background-color: var(--success-color);
}

.toggle-switch input:checked + .toggle-slider:before {
  transform: translateX(20px);
}

.toggle-switch input:focus + .toggle-slider {
  box-shadow: 0 0 0 3px var(--primary-light);
}

/* Slider for PWM */
.sensor-slider {
  width: 100%;
  margin-top: var(--spacing-sm);
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  border-radius: 4px;
  background: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color) 50%, var(--gray-300) 50%, var(--gray-300) 100%);
  outline: none;
  transition: background var(--transition-base);
  /* Ensure touch target height */
  padding: 10px 0;
  cursor: pointer;
}

.sensor-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  border: 2px solid white;
  transition: transform var(--transition-fast);
}

.sensor-slider::-webkit-slider-thumb:active {
  transform: scale(1.2);
}

.sensor-slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  border: 2px solid white;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  transition: transform var(--transition-fast);
}

.sensor-slider::-moz-range-thumb:active {
  transform: scale(1.2);
}

/* Firefox track styling */
.sensor-slider::-moz-range-track {
  background: transparent;
  border: none;
}

/* ============================================
   INFO ROWS (WiFi, Device Info)
   ============================================ */
.info-row,
.device-info .info-row,
.wifi-info .info-row {
  display: flex;
  justify-content: space-between;
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--border-color);
}

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

.info-label {
  font-weight: 600;
  color: var(--text-secondary);
}

.info-value {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-color);
  word-break: break-all;
}

/* WiFi Status Indicator */
.wifi-status-icon {
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: #9ca3af;
  margin-left: 8px;
  vertical-align: middle;
  transition: background-color var(--transition-base);
}

/* WiFi Config */
.wifi-config {
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.wifi-config .input {
  margin-bottom: var(--spacing-sm);
}

.wifi-config #check-wifi-status-btn {
  margin-top: var(--spacing-sm);
  width: 100%;
}

.wifi-config #set-mqtt-btn {
  margin-top: var(--spacing-md);
  width: 100%;
}

/* Password visibility toggle */
.password-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.password-input-wrapper .input {
  flex: 1;
  padding-right: 40px;
}

.password-toggle-btn {
  position: absolute;
  right: 8px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  opacity: 0.6;
  transition: opacity 0.2s;
}

.password-toggle-btn:hover {
  opacity: 1;
}

.password-toggle-btn .eye-icon {
  display: block;
  color: var(--gray-600);
}

.password-toggle-btn .eye-icon.hidden {
  display: none;
}

/* ============================================
   TAB NAVIGATION
   ============================================ */
.tab-nav {
  display: flex;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-md);
  border-bottom: 2px solid var(--gray-300);
}

.tab-btn {
  flex: 1;
  padding: var(--spacing-sm) var(--spacing-md);
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-base);
  margin-bottom: -2px;
}

.tab-btn:hover {
  color: var(--primary-color);
  background-color: var(--gray-100);
}

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

.tab-content {
  display: none;
}

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

/* ============================================
   CONTROLS (Refresh, Auto-refresh)
   ============================================ */
.controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.auto-refresh-controls {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

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

/* ============================================
   PARAMETERS LIST
   ============================================ */
.param-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
}

.param-card {
  background-color: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-md);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
  border-left: 4px solid var(--primary-color);
}

.param-card:active {
  transform: translateY(1px);
}

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

.param-card.success {
  animation: successPulse 0.5s ease-out;
}

@keyframes successPulse {
  0% { border-left-color: var(--primary-color); }
  50% { border-left-color: var(--success-color); box-shadow: 0 0 0 4px var(--success-light); }
  100% { border-left-color: var(--primary-color); }
}

.param-card.error {
  animation: errorShake 0.5s ease-out;
  border-left-color: var(--danger-color);
}

@keyframes errorShake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-4px); }
  75% { transform: translateX(4px); }
}

.param-header {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.param-icon {
  font-size: 1.5rem;
  line-height: 1;
  flex-shrink: 0;
}

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

.param-name {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--gray-800);
  margin-bottom: var(--spacing-xs);
  line-height: 1.3;
}

.param-value-display {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.param-value-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  background-color: var(--primary-light);
  color: var(--primary-dark);
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  border-radius: 6px;
  line-height: 1.4;
}

.param-unit {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.param-controls {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.param-input-row {
  display: flex;
  gap: var(--spacing-sm);
}

.param-input-row .input {
  flex: 1;
  min-height: 44px;
  font-size: 1rem;
  font-family: var(--font-mono);
}

.param-actions {
  display: flex;
  gap: var(--spacing-sm);
}

.param-actions .btn {
  flex: 1;
  min-height: 44px;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.param-btn-icon {
  font-size: 1.1rem;
  line-height: 1;
}

/* Responsive: 2 columns on tablet+ */
@media (min-width: 768px) {
  .param-list {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
  }
}

/* Desktop: 3 columns for better horizontal space utilization */
@media (min-width: 1024px) {
  .param-list {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
  }
}

/* Large desktop: maintain 3 columns with more comfortable spacing */
@media (min-width: 1440px) {
  .param-list {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
  }
}

/* ============================================
   ADMIN SECTION
   ============================================ */
.admin-group {
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background-color: var(--card-bg);
  border-radius: var(--border-radius-sm);
}

.admin-group h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  color: var(--gray-800);
}

.admin-group .input,
.admin-group .textarea {
  margin-bottom: var(--spacing-sm);
}

.cmd-response,
.batch-results {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--gray-900);
  color: var(--success-color);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  border-radius: var(--border-radius-sm);
  white-space: pre-wrap;
  word-break: break-all;
  max-height: 300px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

/* ============================================
   STREAMING SECTION
   ============================================ */
.config-subtitle {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--gray-700);
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.streaming-config {
  margin-bottom: var(--spacing-lg);
}

/* Streaming data groups (High-frequency / Low-frequency) */
.streaming-group {
  margin-bottom: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--gray-50);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}

.streaming-group:last-of-type {
  margin-bottom: var(--spacing-md);
}

.streaming-group-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--gray-700);
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--gray-300);
}

/* Mobile: Single column for checkboxes */
.streaming-options {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

/* Tablet+: Two-column layout for better space utilization */
@media (min-width: 768px) {
  .streaming-options {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm) var(--spacing-md);
  }
}

/* Desktop: Maintain two-column but with more gap */
@media (min-width: 1024px) {
  .streaming-options {
    gap: var(--spacing-sm) var(--spacing-lg);
  }
}

.streaming-option {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--card-bg);
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: all var(--transition-base);
  min-height: var(--touch-target-min);
  border: 2px solid transparent;
  box-shadow: var(--shadow-sm);
}

.streaming-option:hover {
  background-color: var(--gray-100);
  border-color: var(--primary-color);
  box-shadow: var(--shadow-md);
}

.streaming-option:active {
  background-color: var(--gray-200);
  transform: scale(0.98);
}

.streaming-checkbox {
  width: 22px;
  height: 22px;
  cursor: pointer;
  flex-shrink: 0;
  accent-color: var(--primary-color);
}

.streaming-option-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.streaming-option-label {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-color);
  user-select: none;
}

.streaming-option-description {
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--gray-600);
  line-height: 1.3;
}

.streaming-frequency {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.streaming-slider {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 8px;
  border-radius: 4px;
  background: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color) 10%, var(--gray-300) 10%, var(--gray-300) 100%);
  outline: none;
  transition: background var(--transition-base);
  padding: 10px 0;
  cursor: pointer;
}

.streaming-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  border: 3px solid white;
  transition: transform var(--transition-fast);
}

.streaming-slider::-webkit-slider-thumb:active {
  transform: scale(1.2);
}

.streaming-slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  border: 3px solid white;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  transition: transform var(--transition-fast);
}

.streaming-slider::-moz-range-thumb:active {
  transform: scale(1.2);
}

.streaming-slider::-moz-range-track {
  background: transparent;
  border: none;
}

.streaming-freq-display {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm);
  background-color: var(--primary-light);
  border-radius: var(--border-radius-sm);
}

#streaming-freq-value {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.streaming-freq-unit {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.streaming-controls {
  display: flex;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.streaming-controls .btn {
  flex: 1;
}

.streaming-status {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  background-color: var(--gray-100);
  border-radius: var(--border-radius-sm);
}

.streaming-status-indicator {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background-color: var(--gray-400);
  transition: background-color var(--transition-base);
  flex-shrink: 0;
}

.streaming-status-indicator.active {
  background-color: var(--success-color);
  box-shadow: 0 0 10px rgba(40, 167, 69, 0.6);
  animation: pulse 1.5s infinite;
}

.streaming-status-text {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-base);
}

.streaming-status-text.active {
  color: var(--success-color);
  font-weight: 600;
}

.streaming-data-container {
  margin-bottom: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.streaming-data-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
}

.streaming-data-controls {
  display: flex;
  gap: var(--spacing-xs);
}

.streaming-data-display {
  background-color: var(--gray-900);
  color: var(--gray-300);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: var(--spacing-md);
  border-radius: var(--border-radius-sm);
  max-height: 400px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.streaming-message-card {
  background-color: rgba(255, 255, 255, 0.05);
  border-left: 3px solid var(--primary-color);
  padding: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  animation: messageSlideIn 0.2s ease-out;
}

@keyframes messageSlideIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.streaming-message-time {
  font-size: 0.7rem;
  color: var(--warning-color);
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
}

.streaming-message-content {
  color: var(--success-color);
  font-size: 0.75rem;
  white-space: pre-wrap;
  word-break: break-all;
  margin: 0;
}

.streaming-custom-cmd {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.streaming-custom-cmd .input {
  margin-bottom: var(--spacing-sm);
}

/* .streaming-cmd-response styles removed - custom commands now log to Log tab only */

/* Desktop: Vertical layout prioritizing chart prominence */
@media (min-width: 1024px) {
  #streaming-section .card {
    display: block;
  }

  /* Compact horizontal controls layout */
  #streaming-section .streaming-config {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md) var(--spacing-xl);
    align-items: flex-start;
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md);
    background-color: var(--gray-100);
    border-radius: var(--border-radius-sm);
  }

  /* Section headers + content groups */
  #streaming-section .streaming-config > h3 {
    width: 100%;
    margin-top: 0;
    margin-bottom: var(--spacing-sm);
  }

  #streaming-section .streaming-config > h3:not(:first-child) {
    margin-top: var(--spacing-md);
  }

  /* Streaming groups: side-by-side on desktop for better space utilization */
  #streaming-section .streaming-group {
    flex: 1;
    min-width: 300px;
    max-width: 600px;
  }

  /* Frequency slider: more compact */
  #streaming-section .streaming-frequency {
    width: 100%;
    max-width: 400px;
  }

  /* Controls row */
  #streaming-section .streaming-controls {
    width: 100%;
    max-width: 500px;
  }

  /* Status indicator */
  #streaming-section .streaming-status {
    flex: 1;
    min-width: 250px;
  }

  /* Chart gets full width and prominence */
  #streaming-section .streaming-chart-section {
    margin-top: 0;
    margin-bottom: var(--spacing-xl);
  }
}

/* Chart Section */
.streaming-chart-section {
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background-color: var(--card-bg);
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
}

/* Dedicated Chart Tab - Full height optimization */
#chart-section {
  display: flex;
  flex-direction: column;
  /* CRITICAL: Force chart section to fill ALL app-main space */
  flex: 1 1 auto;
  align-self: stretch;
  height: 100%;
  min-height: 0;
  margin: 0 !important;
  padding: 0;
  padding-bottom: 60px; /* Reserve space for bottom navbar (60px tall) */
}

/* Chart Tab Empty State - Better vertical centering when chart disabled */
#chart-section .card:not(.chart-enabled) {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 50vh;
}

#chart-section .streaming-chart-header {
  width: 100%;
}

/* Empty state placeholder message */
.chart-empty-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-xl);
  text-align: center;
  color: var(--text-secondary);
  margin-top: var(--spacing-lg);
}

.chart-empty-placeholder-icon {
  font-size: 4rem;
  opacity: 0.3;
}

.chart-empty-placeholder-text {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.5;
}

#chart-section .card {
  display: flex;
  flex-direction: column;
  flex: 1;
  margin: 0;
  /* FIX: Zero padding to maximize chart space */
  padding: 0;
  overflow: hidden;
  /* Ensure card fills parent */
  min-height: 0;
}

#chart-section .streaming-chart-section {
  display: flex;
  flex-direction: column;
  flex: 1;
  margin: 0;
  padding: 0;
  border: none;
  background-color: transparent;
  /* CRITICAL: min-height: 0 allows flex children to shrink below content size */
  min-height: 0;
  overflow: hidden;
}

#chart-section .streaming-chart-content {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}

#chart-section #chart-container {
  flex: 1;
  min-height: 0;
  height: 100%;
}

/* Reduce spacing for chart header and info to maximize chart space */
#chart-section .streaming-chart-header {
  margin-bottom: 4px;
  padding: 4px 8px;
}

#chart-section .chart-info {
  margin-bottom: 4px;
  padding: 4px 8px;
}

#chart-section .card-title {
  margin-top: 4px;
  margin-bottom: 4px;
  padding: 0 8px;
}

/* Hide device and state sections when chart section is active */
#chart-section.active ~ #device-info-section,
#chart-section.active ~ #status-section {
  display: none !important;
}

/* Alternative: hide via JavaScript when showSection('chart') is called */
.chart-tab-active #device-info-section,
.chart-tab-active #status-section {
  display: none !important;
}

/* On desktop, remove extra margins since grid handles spacing */
@media (min-width: 1024px) {
  .streaming-chart-section {
    margin-top: 0;
    margin-bottom: 0;
  }
}

/* Landscape Orientation - Chart Tab Optimization */
@media screen and (orientation: landscape) and (max-height: 600px) {
  /* Mobile landscape: maximize chart space by compacting UI elements */
  #chart-section .card {
    padding: var(--spacing-xs);
  }

  #chart-section .card-title {
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xs);
  }

  #chart-section .streaming-chart-header {
    margin-bottom: var(--spacing-xs);
  }

  #chart-section .config-subtitle {
    font-size: 0.7rem;
    margin-top: var(--spacing-xs);
    margin-bottom: var(--spacing-xs);
  }

  #chart-section .chart-info {
    padding: var(--spacing-xs);
    margin-bottom: var(--spacing-xs);
  }

  #chart-section .chart-label {
    font-size: 0.7rem;
  }

  #chart-section .chart-current-value {
    font-size: 0.9rem;
  }

  #chart-section #chart-container {
    /* FIX: Remove fixed height override in landscape too */
    min-height: 180px;
  }

  /* Compact button spacing in landscape */
  #chart-section .chart-header-controls {
    gap: var(--spacing-xs);
  }

  #chart-section .btn-small {
    min-height: 28px;
    padding: 0 var(--spacing-xs);
    font-size: 0.7rem;
  }
}

.streaming-chart-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
}

.streaming-chart-header h3 {
  margin: 0;
}

.chart-header-controls {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.streaming-chart-content {
  margin-top: var(--spacing-md);
}

.chart-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-sm);
  padding: var(--spacing-sm);
  background-color: var(--gray-100);
  border-radius: var(--border-radius-sm);
}

.chart-label {
  font-size: 0.875rem;
  font-weight: 600;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
}

.chart-label-left {
  color: #dc3545;
}

.chart-label-center {
  color: #28a745;
  align-items: center;
}

.chart-label-right {
  color: #007bff;
  align-items: flex-end;
}

.chart-current-value {
  font-size: 1.25rem;
  font-weight: 700;
  font-family: var(--font-mono);
  margin-top: 4px;
}

#chart-container {
  width: 100%;
  /* FIX: Remove fixed height, let flex: 1 from parent control size */
  flex: 1;
  min-height: 300px;
  border-radius: var(--border-radius-sm);
  overflow: hidden;
  background-color: white;
  border: 1px solid var(--border-color);
}

/* Desktop: maximize chart height (full viewport minus navbar/controls) */
@media (min-width: 1024px) {
  /* FIX: Remove fixed height override, keep flex: 1 from base rule */
  #chart-section #chart-container {
    /* FIX: Remove min-height override to allow full flex expansion */
    min-height: 400px;
  }
}

/* Large desktop: extra vertical space for data visualization */
@media (min-width: 1440px) {
  #chart-section #chart-container {
    /* FIX: Keep min-height reasonable, flex: 1 will expand as needed */
    min-height: 500px;
  }
}

/* uPlot overrides for mobile */
#chart-container .u-legend {
  font-size: 0.75rem;
}

#chart-container .u-series {
  font-weight: 500;
}

/* ============================================
   LOG SECTION
   ============================================ */
.log-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
}

.log-container {
  background-color: var(--gray-900);
  color: var(--gray-300);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: var(--spacing-md);
  border-radius: var(--border-radius-sm);
  max-height: 500px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;

  /* Allow text selection in log */
  -webkit-user-select: text;
  user-select: text;
}

.log-entry {
  padding: var(--spacing-xs) 0;
  border-bottom: 1px solid var(--gray-800);
  word-break: break-all;
}

.log-entry:last-child {
  border-bottom: none;
}

.log-entry.log-error {
  color: var(--danger-light);
}

.log-entry.log-warn {
  color: var(--warning-light);
}

.log-entry.log-info {
  color: var(--info-light);
}

/* Log custom command input */
.log-custom-cmd {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.log-custom-cmd .input {
  width: 100%;
}

.log-custom-cmd .btn {
  width: 100%;
}

/* Log setup commands row */
.log-setup-row {
  display: flex;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
  flex-wrap: wrap;
}

.log-mqtt-setup {
  flex: 0 0 auto;
  min-width: 150px;
}

.log-mqtt-setup .btn {
  width: 100%;
  white-space: nowrap;
}

/* Log configuration change fieldset - DANGEROUS STYLE */
.log-config-change {
  flex: 1 1 auto;
  min-width: 250px;
  border: 3px solid var(--danger-color);
  border-radius: var(--border-radius);
  padding: var(--spacing-sm) var(--spacing-md);
  margin: 0;
  background-color: var(--danger-light);
}

.log-config-change legend {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--danger-dark);
  padding: 0 var(--spacing-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.config-buttons {
  display: flex;
  gap: var(--spacing-sm);
}

.config-buttons .btn {
  flex: 1;
  white-space: nowrap;
  /* DANGER STYLE for config change buttons */
  background-color: var(--danger-color);
  color: white;
  border: 2px solid var(--danger-dark);
  font-weight: 600;
  box-shadow: 0 2px 4px rgba(220, 53, 69, 0.3);
  transition: all var(--transition-base);
}

.config-buttons .btn:hover {
  background-color: var(--danger-dark);
  box-shadow: 0 4px 8px rgba(220, 53, 69, 0.5);
}

.config-buttons .btn:active {
  transform: scale(0.98);
  box-shadow: 0 1px 2px rgba(220, 53, 69, 0.3);
}

@media (max-width: 768px) {
  .log-setup-row {
    flex-direction: column;
  }

  .log-mqtt-setup,
  .log-config-change {
    width: 100%;
  }
}

/* ============================================
   BOTTOM NAVIGATION
   ============================================ */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;

  display: flex;
  justify-content: space-around;

  height: var(--bottom-nav-height);
  padding-bottom: var(--safe-area-bottom);

  background-color: var(--card-bg);
  border-top: 1px solid var(--border-color);
  box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);

  z-index: 90;
}

.bottom-nav.hidden {
  display: none;
}

.nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);

  background: none;
  border: none;
  cursor: pointer;

  color: var(--text-secondary);
  transition: color var(--transition-base);

  /* Remove tap highlight */
  -webkit-tap-highlight-color: transparent;

  /* Touch target sizing */
  min-height: var(--touch-target-min);
  padding: var(--spacing-sm) 0;
}

.nav-item:active {
  background-color: var(--gray-100);
}

.nav-item.active {
  color: var(--primary-color);
}

.nav-icon {
  font-size: 1.5rem;
  line-height: 1;
}

.nav-label {
  font-size: 0.75rem;
  font-weight: 500;
}

/* ============================================
   INSTALL PROMPT
   ============================================ */
.install-prompt {
  position: fixed;
  bottom: calc(var(--bottom-nav-height) + var(--safe-area-bottom));
  left: var(--spacing-md);
  right: var(--spacing-md);

  background-color: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
  padding: var(--spacing-md);

  z-index: 80;

  animation: slideUp 0.3s ease-out;
}

.install-prompt.hidden {
  display: none;
}

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

.install-content p {
  margin-bottom: var(--spacing-md);
  color: var(--text-color);
}

/* ============================================
   LOADING OVERLAY
   ============================================ */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;

  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-md);

  background-color: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);

  z-index: 200;
}

.loading-overlay.hidden {
  display: none;
}

/* Global loading: higher z-index, darker background, blocks EVERYTHING */
.loading-overlay.global-loading {
  z-index: 999;
  background-color: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--gray-500);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

/* Larger spinner for global loading */
.loading-overlay.global-loading .spinner {
  width: 64px;
  height: 64px;
  border-width: 6px;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-text {
  color: white;
  font-size: 1rem;
  font-weight: 500;
  text-align: center;
  padding: 0 var(--spacing-md);
  max-width: 80%;
}

/* Larger, more prominent text for global loading */
.loading-overlay.global-loading .loading-text {
  font-size: 1.125rem;
  font-weight: 600;
}

/* ============================================
   TOAST NOTIFICATIONS
   ============================================ */
.toast-container {
  position: fixed;
  top: calc(var(--safe-area-top) + var(--spacing-md));
  left: var(--spacing-md);
  right: var(--spacing-md);

  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);

  z-index: 300;
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);

  padding: var(--spacing-md);
  background-color: var(--card-bg);
  border-radius: var(--border-radius-sm);
  box-shadow: var(--shadow-lg);

  border-left: 4px solid var(--gray-500);

  pointer-events: auto;

  animation: toastSlideIn 0.3s ease-out;
}

@keyframes toastSlideIn {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

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

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

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

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

.toast-message {
  flex: 1;
  font-size: 0.875rem;
  color: var(--text-color);
}

.toast-close {
  background: none;
  border: none;
  font-size: 1.25rem;
  line-height: 1;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0;
  min-width: auto;
  min-height: auto;
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.hidden {
  display: none !important;
}

.text-center {
  text-align: center;
}

.text-mono {
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }

/* ============================================
   SKELETON LOADING STATES
   ============================================ */
.skeleton {
  background: linear-gradient(90deg, var(--gray-200) 25%, var(--gray-300) 50%, var(--gray-200) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--border-radius-sm);
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-text {
  height: 1rem;
  margin-bottom: var(--spacing-sm);
}

.skeleton-card {
  height: 120px;
}

/* ============================================
   RESPONSIVE - TABLET & DESKTOP
   ============================================ */

/* Tablet (768px - 1024px): 3-4 columns */
@media (min-width: 768px) {
  .app-main {
    width: 100%; /* CRITICAL: Force expansion to available width */
    max-width: 1200px; /* Increased from 1024px to use more screen space */
    margin-left: auto;
    margin-right: auto;
    padding: var(--spacing-lg);
    padding-bottom: calc(var(--bottom-nav-height) + var(--spacing-lg));
  }

  .sensor-grid {
    /* Tablet: 3-4 columns */
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
  }

  .sensor-card {
    padding: 14px;
    min-height: 110px;
  }

  .sensor-name {
    font-size: 0.875rem;
  }

  .sensor-value {
    font-size: 1.6rem;
  }

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

  .bottom-nav {
    max-width: 1200px; /* Match .app-main width */
    left: 50%;
    transform: translateX(-50%);
  }

  .install-prompt {
    max-width: 400px;
    left: 50%;
    transform: translateX(-50%);
  }
}

/* Desktop (1024px+): 4-6 columns */
@media (min-width: 1024px) {
  .sensor-grid {
    /* Desktop: 5 columns (increased from 4) */
    grid-template-columns: repeat(5, 1fr);
    gap: 16px;
  }

  .sensor-card {
    padding: 16px;
    min-height: 120px;
  }

  .sensor-name {
    font-size: 0.9rem;
  }

  .sensor-value {
    font-size: 1.75rem;
  }
}

/* Large Desktop (1440px+): More comfortable spacing */
@media (min-width: 1440px) {
  .app-main {
    width: 100%; /* CRITICAL: Force expansion to available width */
    max-width: 1600px; /* Increased from 1280px to utilize wide screens */
    margin-left: auto;
    margin-right: auto;
  }

  .sensor-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); /* Reduced min-width from 160px to allow more columns */
    gap: 20px;
  }

  .bottom-nav {
    max-width: 1600px; /* Match .app-main width */
  }
}

/* Extra Large Desktop (1920px+): Maximum utilization for ultra-wide displays */
@media (min-width: 1920px) {
  .app-main {
    width: 100%; /* CRITICAL: Force expansion to available width */
    max-width: 1800px; /* Allow even more space on ultra-wide displays */
    margin-left: auto;
    margin-right: auto;
  }

  .sensor-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 24px; /* Increased gap for better visual spacing */
  }

  .bottom-nav {
    max-width: 1800px;
  }
}

/* ============================================
   PLATFORM-SPECIFIC FIXES
   ============================================ */

/* iOS Safari - Prevent zoom on input focus */
@supports (-webkit-touch-callout: none) {
  input[type="text"],
  input[type="password"],
  textarea {
    font-size: 16px; /* Prevents auto-zoom on iOS */
  }
}

/* iOS Safari - Fix 100vh with address bar */
@supports (-webkit-appearance: none) {
  body {
    min-height: 100vh;
    min-height: -webkit-fill-available;
  }
}

/* Android Chrome - System bars handling */
@supports (padding: max(0px)) {
  .app-header {
    padding-top: max(var(--safe-area-top), var(--spacing-md));
  }

  .bottom-nav {
    padding-bottom: max(var(--safe-area-bottom), var(--spacing-sm));
  }
}

/* ============================================
   FAN CARD (ALLMAND ONLY)
   ============================================ */
.fan-card {
  margin-top: var(--spacing-md);
  background-color: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: all var(--transition-base);
}

.fan-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md);
  background-color: var(--gray-100);
  border-bottom: 2px solid var(--border-color);
  cursor: pointer;
  -webkit-user-select: none;
  user-select: none;
}

.fan-header:active {
  background-color: var(--gray-200);
}

.fan-header .card-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  color: var(--gray-800);
}

.btn-collapse {
  background: none;
  border: none;
  font-size: 1.25rem;
  line-height: 1;
  color: var(--text-secondary);
  cursor: pointer;
  padding: var(--spacing-xs);
  min-width: var(--touch-target-min);
  min-height: var(--touch-target-min);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-fast), color var(--transition-base);
  -webkit-tap-highlight-color: transparent;
}

.btn-collapse:active {
  transform: scale(0.95);
}

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

.fan-content {
  padding: var(--spacing-md);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.fan-content.hidden {
  display: none;
}

.fan-speeds {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-md);
}

.fan-metric {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
  padding: var(--spacing-md);
  background-color: var(--gray-100);
  border-radius: var(--border-radius-sm);
  border-left: 4px solid var(--primary-color);
}

.fan-metric-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.fan-metric-value {
  font-size: 1.5rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--text-color);
}

.fan-status {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  background-color: var(--gray-50);
  border-radius: var(--border-radius-sm);
}

.fan-status-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.fan-status-value {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--text-color);
}

.fan-alarms {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  background-color: var(--danger-light);
  border-radius: var(--border-radius-sm);
  border-left: 4px solid var(--danger-color);
  margin-top: var(--spacing-sm);
}

.fan-alarms-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--danger-dark);
}

.fan-alarms-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.fan-alarm-item {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--danger-dark);
  padding: 0.25rem 0.5rem;
  background-color: rgba(255, 255, 255, 0.5);
  border-radius: var(--border-radius-sm);
}

/* Fan Speed Slider Control */
.fan-speed-control {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  background-color: var(--gray-50);
  border-radius: var(--border-radius-sm);
  margin-top: var(--spacing-sm);
}

.fan-speed-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-xs);
}

.fan-speed-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.fan-speed-value {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  color: var(--primary-color);
}

.fan-speed-slider {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 8px;
  border-radius: 4px;
  background: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color) 0%, var(--gray-300) 0%, var(--gray-300) 100%);
  outline: none;
  transition: background var(--transition-base);
  padding: 10px 0;
  cursor: pointer;
}

.fan-speed-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  border: 3px solid white;
  transition: transform var(--transition-fast);
}

.fan-speed-slider::-webkit-slider-thumb:active {
  transform: scale(1.2);
}

.fan-speed-slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  border: 3px solid white;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  transition: transform var(--transition-fast);
}

.fan-speed-slider::-moz-range-thumb:active {
  transform: scale(1.2);
}

.fan-speed-slider::-moz-range-track {
  background: transparent;
  border: none;
}

#fan-speed-send-btn {
  width: 100%;
  margin-top: var(--spacing-xs);
}

/* Fan Alarm History */
.fan-alarm-history {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  background-color: var(--warning-light);
  border-radius: var(--border-radius-sm);
  border-left: 4px solid var(--warning-color);
  margin-top: var(--spacing-sm);
  max-height: 300px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.fan-alarm-history-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-xs);
}

.fan-alarm-history-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.fan-alarm-history-item {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--warning-dark);
  padding: 0.5rem;
  background-color: rgba(255, 255, 255, 0.7);
  border-radius: var(--border-radius-sm);
  border-left: 3px solid var(--warning-color);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.fan-alarm-history-timestamp {
  font-size: 0.7rem;
  color: var(--text-secondary);
  font-weight: 600;
}

.fan-alarm-history-codes {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
}

.fan-alarm-history-code {
  font-size: 0.7rem;
  color: var(--danger-dark);
}

/* Badge Styles (for status indicators) */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background-color: var(--gray-300);
  color: var(--gray-800);
  transition: all var(--transition-base);
}

.badge-success {
  background-color: var(--success-light);
  color: var(--success-dark);
  border: 1px solid var(--success-color);
}

.badge-danger {
  background-color: var(--danger-light);
  color: var(--danger-dark);
  border: 1px solid var(--danger-color);
  animation: badgePulse 1.5s infinite;
}

@keyframes badgePulse {
  0%, 100% {
    box-shadow: 0 0 0 rgba(220, 53, 69, 0.4);
  }
  50% {
    box-shadow: 0 0 8px rgba(220, 53, 69, 0.6);
  }
}

.badge-warning {
  background-color: var(--warning-light);
  color: var(--warning-dark);
  border: 1px solid var(--warning-color);
}

.badge-secondary {
  background-color: var(--secondary-light);
  color: var(--secondary-dark);
  border: 1px solid var(--secondary-color);
}

/* Responsive: Single column on narrow screens */
@media (max-width: 480px) {
  .fan-speeds {
    grid-template-columns: 1fr;
  }
}

/* Desktop: More comfortable spacing */
@media (min-width: 768px) {
  .fan-content {
    padding: var(--spacing-lg);
  }

  .fan-metric-value {
    font-size: 1.75rem;
  }
}

/* ============================================
   PRINT STYLES (for debugging)
   ============================================ */
@media print {
  .bottom-nav,
  .install-prompt,
  .loading-overlay,
  .toast-container {
    display: none !important;
  }
}