:root {
  --bg-canvas: #0a0c10;
  --bg-panel: #11141b;
  --bg-card: #12151d;
  --bg-elevated: #171b24;
  --bg-input: #0d1016;
  --border-subtle: #212631;
  --border-strong: #2d3443;
  --text-main: #ededef;
  --text-secondary: #9ba3b0;
  --text-muted: #6e7785;
  --primary: #2f6feb;
  --primary-hover: #3879f5;
  --success: #2da44e;
  --warning: #d29922;
  --danger: #cf222e;
  --radius-lg: 8px;
  --radius-md: 6px;
  --radius-sm: 4px;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-canvas);
  color: var(--text-main);
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

.hidden {
  display: none !important;
}

/* ================= MÀN HÌNH ĐĂNG NHẬP ================= */
.login-overlay {
  position: fixed;
  inset: 0;
  background-color: var(--bg-canvas);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 1000;
}

.login-card {
  width: 100%;
  max-width: 400px;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
}

.login-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-subtle);
}

.brand-mark {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-main);
}

.brand-mark svg {
  width: 20px;
  height: 20px;
}

.login-brand h1 {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.3px;
  color: var(--text-main);
}

.login-brand p {
  font-size: 12.5px;
  color: var(--text-muted);
  margin-top: 3px;
}

.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 12.5px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-group input,
.select-input,
.search-box input,
.terminal-input-row input,
.board-controls input,
#board-content {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 9px 12px;
  border-radius: var(--radius-md);
  font-size: 13.5px;
  font-family: inherit;
  transition: border-color 0.15s ease;
}

.form-group input:focus,
.select-input:focus,
.search-box input:focus,
.terminal-input-row input:focus,
.board-controls input:focus,
#board-content:focus {
  outline: none;
  border-color: var(--primary);
}

.login-error {
  background: rgba(207, 34, 46, 0.12);
  border: 1px solid rgba(207, 34, 46, 0.35);
  color: #ff8182;
  padding: 9px 12px;
  border-radius: var(--radius-sm);
  font-size: 12.5px;
  margin-bottom: 14px;
}

.login-footer {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
  text-align: center;
  font-size: 11.5px;
  color: var(--text-muted);
}

/* ================= NÚT BẤM ================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 7px 12px;
  border-radius: var(--radius-md);
  font-size: 13px;
  font-weight: 500;
  border: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease;
  text-decoration: none;
  color: var(--text-main);
  white-space: nowrap;
}

.btn:hover {
  background: #1f2532;
  border-color: var(--border-strong);
}

.btn:active {
  background: #141821;
}

.btn-block { width: 100%; }
.btn-lg { padding: 10px 16px; font-size: 13.5px; font-weight: 600; }
.btn-sm { padding: 5px 10px; font-size: 12px; border-radius: var(--radius-sm); }
.btn-xs { padding: 4px 8px; font-size: 11.5px; border-radius: var(--radius-sm); }

.btn-primary,
.btn-Broadcast,
.btn-accent {
  background: var(--primary);
  border-color: var(--primary);
  color: #ffffff;
}
.btn-primary:hover,
.btn-Broadcast:hover,
.btn-accent:hover {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
}

.btn-success {
  background: var(--bg-elevated);
  border-color: rgba(45, 164, 78, 0.45);
  color: #4ac26b;
}
.btn-success:hover {
  background: rgba(45, 164, 78, 0.14);
  border-color: #2da44e;
}

.btn-warning {
  background: var(--bg-elevated);
  border-color: rgba(210, 153, 34, 0.45);
  color: #e3b341;
}
.btn-warning:hover {
  background: rgba(210, 153, 34, 0.14);
  border-color: #d29922;
}

.btn-danger {
  background: var(--danger);
  border-color: var(--danger);
  color: #ffffff;
}
.btn-danger:hover {
  background: #b91c26;
  border-color: #b91c26;
}

.btn-danger-soft {
  background: var(--bg-elevated);
  border-color: rgba(207, 34, 46, 0.4);
  color: #ff8182;
}
.btn-danger-soft:hover {
  background: rgba(207, 34, 46, 0.14);
  border-color: #cf222e;
}

.btn-info,
.btn-secondary {
  background: var(--bg-elevated);
  border-color: var(--border-subtle);
  color: var(--text-main);
}

.btn-outline {
  background: transparent;
  border-color: var(--border-subtle);
  color: var(--text-secondary);
}
.btn-outline:hover {
  color: var(--text-main);
  background: var(--bg-elevated);
}

/* ================= HEADER & THỐNG KÊ ================= */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding: 12px 24px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 100;
}

.topbar-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-badge {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-main);
}

.logo-badge svg { width: 18px; height: 18px; }

.app-title {
  font-size: 15px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-main);
}

.app-env-tag {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  padding: 1px 7px;
  border-radius: var(--radius-sm);
}

.conn-pill {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.conn-pill::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  display: inline-block;
}

.conn-pill.online {
  background: rgba(45, 164, 78, 0.1);
  color: #4ac26b;
  border: 1px solid rgba(45, 164, 78, 0.3);
}
.conn-pill.online::before {
  background: #4ac26b;
}

.conn-pill.offline {
  background: rgba(207, 34, 46, 0.12);
  color: #ff8182;
  border: 1px solid rgba(207, 34, 46, 0.3);
}
.conn-pill.offline::before {
  background: #ff8182;
}

.app-subtitle {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 2px;
}

.stats-strip {
  display: flex;
  align-items: center;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.stat-item {
  padding: 6px 16px;
  display: flex;
  align-items: baseline;
  gap: 8px;
  border-right: 1px solid var(--border-subtle);
}

.stat-item:last-child {
  border-right: none;
}

.stat-label {
  font-size: 12px;
  color: var(--text-secondary);
}

.stat-val {
  font-size: 14px;
  font-weight: 600;
  font-family: 'JetBrains Mono', monospace;
  color: var(--text-main);
}

.stat-online .stat-val { color: #4ac26b; }
.stat-locked .stat-val { color: #e3b341; }
.stat-veyon .stat-val { color: var(--text-secondary); }

.topbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ================= BANNER TRÌNH CHIẾU ================= */
.broadcast-banner {
  background: rgba(207, 34, 46, 0.14);
  border-bottom: 1px solid rgba(207, 34, 46, 0.35);
  padding: 9px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
}

.broadcast-banner-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.pulse-red {
  width: 8px;
  height: 8px;
  background: #ff8182;
  border-radius: 50%;
}

/* ================= THANH CÔNG CỤ ĐIỀU KHIỂN ================= */
.control-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding: 10px 24px;
  background: var(--bg-canvas);
  border-bottom: 1px solid var(--border-subtle);
}

.selection-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.checkbox-wrap {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-secondary);
  cursor: pointer;
  user-select: none;
  background: var(--bg-panel);
  padding: 7px 11px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}

.checkbox-wrap strong {
  color: var(--text-main);
  font-weight: 600;
}

.checkbox-wrap input {
  width: 14px;
  height: 14px;
  accent-color: var(--primary);
}

.search-box input {
  width: 240px;
  padding: 7px 11px;
}

.select-input {
  width: auto;
  padding: 7px 11px;
}

.action-buttons {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.btn-cluster {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding-right: 8px;
  border-right: 1px solid var(--border-subtle);
}

.btn-cluster:last-child {
  padding-right: 0;
  border-right: none;
}

/* ================= LƯỚI MÁY HỌC SINH ================= */
.main-content {
  padding: 20px 24px 48px;
}

.machines-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
}

.machine-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: border-color 0.15s ease;
}

.machine-card:hover {
  border-color: var(--border-strong);
}

.machine-card.selected {
  border-color: rgba(47, 111, 235, 0.65);
}

.machine-card.is-locked {
  border-color: rgba(210, 153, 34, 0.65);
}

.machine-card.is-broadcast {
  border-color: var(--primary);
}

.machine-card.is-offline {
  opacity: 0.65;
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border-subtle);
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: 9px;
}

.card-check {
  width: 14px;
  height: 14px;
  accent-color: var(--primary);
  cursor: pointer;
}

.slot-badge {
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  color: var(--text-main);
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  min-width: 34px;
  text-align: center;
  cursor: pointer;
}

.machine-name {
  font-weight: 600;
  font-size: 13.5px;
  color: var(--text-main);
}

.machine-room {
  font-size: 11.5px;
  color: var(--text-muted);
  font-family: 'JetBrains Mono', monospace;
}

.status-pill {
  font-size: 11px;
  font-weight: 500;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
}

.status-pill.online {
  background: rgba(45, 164, 78, 0.1);
  border-color: rgba(45, 164, 78, 0.3);
  color: #4ac26b;
}
.status-pill.locked {
  background: rgba(210, 153, 34, 0.12);
  border-color: rgba(210, 153, 34, 0.35);
  color: #e3b341;
}
.status-pill.broadcast {
  background: rgba(47, 111, 235, 0.14);
  border-color: rgba(47, 111, 235, 0.4);
  color: #79c0ff;
}
.status-pill.offline {
  background: var(--bg-elevated);
  border-color: var(--border-subtle);
  color: var(--text-muted);
}

.screen-box {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #07090d;
  overflow: hidden;
  cursor: pointer;
}

.screen-box img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.screen-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 12px;
  gap: 4px;
}

.card-meta {
  padding: 8px 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 11px;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-input);
}

.meta-chip {
  color: var(--text-secondary);
  font-family: 'JetBrains Mono', monospace;
}

.meta-chip + .meta-chip::before {
  content: "·";
  margin-right: 6px;
  color: var(--border-strong);
}

.card-actions {
  padding: 8px 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 6px;
  background: var(--bg-card);
}

/* ================= EMPTY STATE ================= */
.empty-state {
  max-width: 560px;
  margin: 56px auto;
  text-align: center;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
}

.empty-state h2 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 22px;
}

.empty-actions {
  display: flex;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
}

/* ================= MODALS ================= */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(5, 7, 10, 0.78);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 500;
}

.modal-box {
  width: 100%;
  max-width: 480px;
  background: var(--bg-panel);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  max-height: 92vh;
  display: flex;
  flex-direction: column;
}

.modal-box.modal-lg { max-width: 800px; }
.modal-box.modal-xl { max-width: 1100px; }

.modal-header {
  padding: 14px 20px;
  background: var(--bg-input);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-header h3 {
  font-size: 15px;
  font-weight: 600;
}

.modal-sub {
  font-size: 12px;
  color: var(--text-muted);
  display: block;
  margin-top: 2px;
}

.modal-close {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 16px;
  cursor: pointer;
}

.modal-close:hover {
  color: var(--text-main);
}

.modal-body {
  padding: 18px 20px;
  overflow-y: auto;
}

.modal-footer, .modal-footer-inline {
  padding: 12px 20px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.modal-footer-inline {
  padding: 12px 0 0;
  margin-top: 12px;
}

/* Broadcast Studio Tabs */
.tabs-bar {
  display: flex;
  gap: 6px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 10px;
  flex-wrap: wrap;
}

.tab-btn {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  padding: 7px 12px;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-weight: 500;
  font-size: 12.5px;
}

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

.tab-hint {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.board-controls {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
}

.canvas-preview-wrap {
  margin-top: 12px;
  background: #000;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  aspect-ratio: 16 / 9;
  max-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.canvas-preview-wrap canvas {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.alert-box {
  background: rgba(210, 153, 34, 0.1);
  border: 1px solid rgba(210, 153, 34, 0.35);
  padding: 12px 14px;
  border-radius: var(--radius-md);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 12.5px;
}

.live-view-body {
  background: #05070a;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 460px;
}

.live-view-body img {
  width: 100%;
  max-height: 75vh;
  object-fit: contain;
}

.live-view-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}

/* Installer Modal */
.installer-card {
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 14px;
}

.installer-card.highlight {
  border-color: rgba(47, 111, 235, 0.5);
}

.installer-card h4 {
  margin-bottom: 6px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-main);
}

.installer-card p {
  font-size: 12.5px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.installer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

@media (max-width: 680px) {
  .installer-grid {
    grid-template-columns: 1fr;
  }
}

.installer-col {
  background: var(--bg-panel);
  padding: 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}

.os-label {
  display: block;
  font-size: 12px;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.installer-buttons {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.code-copy-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  background: var(--bg-canvas);
  border: 1px solid var(--border-subtle);
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  font-family: 'JetBrains Mono', monospace;
  font-size: 11.5px;
  color: var(--text-main);
  margin-bottom: 8px;
  overflow-x: auto;
}

/* Terminal Modal */
.terminal-input-row {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
}

.quick-cmds {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.terminal-output {
  background: #06080b;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 12px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: var(--text-main);
  min-height: 220px;
  max-height: 360px;
  overflow-y: auto;
  white-space: pre-wrap;
}

/* Toast */
.toast-container {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 2000;
}

.toast {
  background: var(--bg-panel);
  border: 1px solid var(--border-strong);
  border-left: 3px solid var(--primary);
  color: var(--text-main);
  padding: 10px 14px;
  border-radius: var(--radius-md);
  font-size: 13px;
  font-weight: 500;
}