:root {
  --bg-color: #0d1117;
  --panel-bg: #161b22;
  --text-color: #c9d1d9;
  --text-muted: #8b949e;
  --border-color: #30363d;
  --primary-color: #58a6ff;
  --success-color: #2ea043;
  --danger-color: #da3633;
  --warning-color: #d29922;
  
  --btn-bg: #21262d;
  --btn-hover: #30363d;
  --btn-border: rgba(240, 246, 252, 0.1);
}

body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  display: flex;
  justify-content: center;
  min-height: 100vh;
}

#root {
  width: 100%;
  max-width: 1200px;
  padding: 20px;
  box-sizing: border-box;
}

/* ====================== App Title ====================== */
.app-title {
  text-align: center;
  color: var(--primary-color);
  font-size: 1.5rem;
  margin: 0 0 16px 0;
}

/* ====================== Tab Bar ====================== */
.tab-bar {
  display: flex;
  gap: 4px;
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 10px 10px 0 0;
  padding: 4px 4px 0 4px;
}

.tab-btn {
  flex: 1;
  padding: 12px 20px;
  border: none;
  border-radius: 8px 8px 0 0;
  background-color: transparent;
  color: var(--text-muted);
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.tab-btn:hover {
  background-color: rgba(255,255,255,0.05);
  color: var(--text-color);
}

.tab-btn.active {
  background-color: var(--bg-color);
  color: var(--primary-color);
  border-bottom: 2px solid var(--primary-color);
}

.tab-content {
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  border-top: none;
  border-radius: 0 0 10px 10px;
  padding: 20px;
}

/* ====================== Tab Panel Layout ====================== */
.tab-panel {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.tab-main {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 16px;
  min-height: 300px;
}

@media (max-width: 768px) {
  .tab-main {
    grid-template-columns: 1fr;
  }
}

/* ====================== Device List ====================== */
.device-list {
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow: hidden;
}

.device-list-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border-color);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--primary-color);
}

.btn-add {
  padding: 4px 12px !important;
  font-size: 0.85rem !important;
  background: rgba(88, 166, 255, 0.12) !important;
  color: var(--primary-color) !important;
  border-color: rgba(88, 166, 255, 0.25) !important;
}
.btn-add:active {
  background: rgba(88, 166, 255, 0.3) !important;
}

.device-empty {
  padding: 20px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.device-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  cursor: pointer;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.1s;
}

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

.device-item:hover {
  background-color: rgba(255,255,255,0.03);
}

.device-item.selected {
  background-color: rgba(88, 166, 255, 0.1);
  border-left: 3px solid var(--primary-color);
}

.device-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.device-name {
  font-weight: 600;
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.device-detail {
  font-size: 0.78rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.device-actions {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}

.btn-icon {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 0.9rem;
  padding: 4px;
  border-radius: 4px;
  transition: background 0.1s;
}
.btn-icon:hover {
  background-color: rgba(255,255,255,0.08);
}

/* ====================== Device Status Dot ====================== */
.device-status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
  display: inline-block;
  margin-right: 6px;
  transition: background-color 0.3s ease;
}
.device-status-dot.online {
  background-color: var(--success-color);
  box-shadow: 0 0 6px var(--success-color);
  animation: statusPulse 2s ease-in-out infinite;
}
.device-status-dot.offline {
  background-color: var(--danger-color);
  box-shadow: 0 0 4px rgba(218, 54, 51, 0.4);
}
.device-status-dot.unknown {
  background-color: var(--text-muted);
  box-shadow: none;
}

@keyframes statusPulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 6px var(--success-color); }
  50% { opacity: 0.6; box-shadow: 0 0 2px var(--success-color); }
}

.btn-check-status {
  padding: 4px 10px !important;
  font-size: 0.8rem !important;
  background: rgba(46, 160, 67, 0.12) !important;
  color: var(--success-color) !important;
  border-color: rgba(46, 160, 67, 0.25) !important;
  margin-left: 6px;
}
.btn-check-status:active {
  background: rgba(46, 160, 67, 0.3) !important;
}
.btn-check-status:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ====================== Panel ====================== */
.panel {
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.panel h2 {
  margin-top: 0;
  margin-bottom: 16px;
  font-size: 1.15rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 10px;
  color: var(--primary-color);
}

.control-panel {
  min-height: 200px;
}

.device-info-bar {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  padding: 6px 10px;
  background: rgba(255,255,255,0.03);
  border-radius: 4px;
}

.empty-state {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 200px;
  color: var(--text-muted);
  font-size: 1rem;
}

/* ====================== Controls ====================== */
.controls-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 15px;
}

.btn {
  background-color: var(--btn-bg);
  color: var(--text-color);
  border: 1px solid var(--btn-border);
  border-radius: 6px;
  padding: 12px 16px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.1s ease;
  box-shadow: none;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

.btn:active {
  background-color: rgba(255, 255, 255, 0.2);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.4);
}

.btn-primary {
  background-color: var(--btn-bg);
  color: var(--text-color);
  border-color: var(--btn-border);
}
.btn-primary:active {
  background-color: rgba(255, 255, 255, 0.2);
  color: #fff;
}

/* ====================== Form ====================== */
.form-group {
  margin-bottom: 15px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 5px;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 8px 12px;
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-color);
  box-sizing: border-box;
  font-size: 0.95rem;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.3);
}

.form-group select {
  appearance: auto;
}

.form-row {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 10px;
}

@media (max-width: 600px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

/* ====================== Modal ====================== */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  animation: fadeIn 0.15s ease;
}

.modal-content {
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 24px;
  width: 90%;
  max-width: 500px;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: 0 8px 24px rgba(0,0,0,0.5);
}

.modal-content h3 {
  margin: 0 0 16px 0;
  font-size: 1.2rem;
  color: var(--primary-color);
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 20px;
}

/* ====================== Command Feedback ====================== */
.command-feedback {
  margin-top: 12px;
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 500;
  text-align: center;
  animation: fadeIn 0.2s ease;
}

.command-feedback.sending {
  background-color: rgba(88, 166, 255, 0.15);
  color: var(--primary-color);
  border: 1px solid rgba(88, 166, 255, 0.3);
}

.command-feedback.success {
  background-color: rgba(46, 160, 67, 0.15);
  color: var(--success-color);
  border: 1px solid rgba(46, 160, 67, 0.3);
}

.command-feedback.error {
  background-color: rgba(218, 54, 51, 0.15);
  color: var(--danger-color);
  border: 1px solid rgba(218, 54, 51, 0.3);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ====================== Log Table ====================== */
.log-container {
  max-height: 400px;
  overflow-y: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

th, td {
  padding: 10px;
  border-bottom: 1px solid var(--border-color);
}

th {
  color: var(--text-muted);
  font-size: 0.85rem;
  text-transform: uppercase;
  background-color: var(--bg-color);
  position: sticky;
  top: 0;
}

/* ====================== Text Display Controls ====================== */
.td-params {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
  margin-bottom: 16px;
}

.td-actions {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-top: 4px;
}

.btn-td {
  padding: 12px 8px;
  font-size: 0.95rem;
  font-weight: 700;
  border-radius: 8px;
  transition: all 0.15s ease;
}

.btn-td:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-interrupt {
  background: rgba(245, 158, 11, 0.15);
  color: #f59e0b;
  border-color: rgba(245, 158, 11, 0.3);
}
.btn-interrupt:active:not(:disabled) {
  background: rgba(245, 158, 11, 0.35);
}

.btn-fixed {
  background: rgba(6, 182, 212, 0.15);
  color: #06b6d4;
  border-color: rgba(6, 182, 212, 0.3);
}
.btn-fixed:active:not(:disabled) {
  background: rgba(6, 182, 212, 0.35);
}

.btn-marquee {
  background: rgba(34, 197, 94, 0.15);
  color: #22c55e;
  border-color: rgba(34, 197, 94, 0.3);
}
.btn-marquee:active:not(:disabled) {
  background: rgba(34, 197, 94, 0.35);
}

.btn-reset {
  background: rgba(139, 148, 158, 0.15);
  color: #8b949e;
  border-color: rgba(139, 148, 158, 0.3);
}
.btn-reset:active {
  background: rgba(139, 148, 158, 0.35);
}

/* ====================== Log Toolbar ====================== */
.log-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
  gap: 12px;
}

.filter-input {
  flex: 0 1 300px;
  padding: 8px 12px;
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-color);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.15s;
}

.filter-input:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.2);
}

.log-info {
  font-size: 0.82rem;
  color: var(--text-muted);
  white-space: nowrap;
}

/* ====================== Sortable Table Headers ====================== */
th.sortable {
  cursor: pointer;
  user-select: none;
  transition: color 0.1s;
}

th.sortable:hover {
  color: var(--primary-color);
}

.sort-arrow {
  font-size: 0.7rem;
  margin-left: 2px;
}

/* ====================== Pagination ====================== */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border-color);
}

.page-btn {
  background-color: var(--btn-bg);
  color: var(--text-color);
  border: 1px solid var(--btn-border);
  border-radius: 4px;
  padding: 4px 10px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 600;
  transition: all 0.1s;
}

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

.page-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.page-info {
  font-size: 0.85rem;
  color: var(--text-muted);
  min-width: 100px;
  text-align: center;
}

/* ====================== MQTT Tab ====================== */
.mqtt-top-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

@media (max-width: 768px) {
  .mqtt-top-grid {
    grid-template-columns: 1fr;
  }
}

.mqtt-settings-panel,
.mqtt-status-panel {
  min-height: 200px;
}

/* MQTT Status Display */
.mqtt-status-display {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  padding: 12px 16px;
  background: rgba(255,255,255,0.03);
  border-radius: 8px;
}

.mqtt-status-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  flex-shrink: 0;
  box-shadow: 0 0 8px currentColor;
}

.mqtt-status-text {
  font-size: 1.1rem;
  font-weight: 600;
}

.mqtt-status-info {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  padding: 4px 8px;
}

.mqtt-status-error {
  font-size: 0.85rem;
  color: var(--danger-color);
  margin-bottom: 8px;
  padding: 4px 8px;
  background: rgba(218, 54, 51, 0.08);
  border-radius: 4px;
}

.mqtt-connect-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 12px;
}

/* MQTT Test Panel */
.mqtt-test-panel h3 {
  margin: 0 0 12px 0;
  font-size: 0.95rem;
  color: var(--text-color);
}

.mqtt-test-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

@media (max-width: 900px) {
  .mqtt-test-grid {
    grid-template-columns: 1fr;
  }
}

.mqtt-test-section {
  padding: 16px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-color);
  border-radius: 8px;
}