/* ==========================================================================
   Talent Traders - Modern Whiteboard & Blackboard Styling
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  
  /* Brand colors */
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --accent: #06b6d4;
  
  /* UI Surface Theme (Default Topbars) */
  --ui-bg: rgba(255, 255, 255, 0.85);
  --ui-bg-solid: #ffffff;
  --ui-border: rgba(226, 232, 240, 0.9);
  --ui-border-focus: #3b82f6;
  --ui-text: #0f172a;
  --ui-text-muted: #64748b;
  --ui-shadow: 0 4px 20px -2px rgba(0, 0, 0, 0.08), 0 2px 6px -1px rgba(0, 0, 0, 0.04);
  --ui-shadow-lg: 0 12px 32px -4px rgba(0, 0, 0, 0.12), 0 4px 12px -2px rgba(0, 0, 0, 0.06);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-full: 9999px;
  --transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Dark UI mode for chrome when in Blackboard mode or dark preference */
body.mode-blackboard {
  --ui-bg: rgba(24, 24, 27, 0.88);
  --ui-bg-solid: #18181b;
  --ui-border: rgba(63, 63, 70, 0.7);
  --ui-border-focus: #38bdf8;
  --ui-text: #f4f4f5;
  --ui-text-muted: #a1a1aa;
  --ui-shadow: 0 4px 24px -2px rgba(0, 0, 0, 0.4);
  --ui-shadow-lg: 0 12px 36px -4px rgba(0, 0, 0, 0.6);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-font-smoothing: antialiased;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: var(--font-sans);
  color: var(--ui-text);
  background-color: #f1f5f9;
  user-select: none;
}

/* App Layout */
#app-container {
  position: relative;
  width: 100vw;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ==========================================================================
   Canvas Viewport & Layers
   ========================================================================== */

#canvas-container {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  touch-action: none;
}

#canvas-bg,
#canvas-main,
#canvas-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: block;
}

#canvas-bg {
  z-index: 1;
}

#canvas-main {
  z-index: 2;
  pointer-events: none;
}

#canvas-overlay {
  z-index: 3;
}

/* ==========================================================================
   Tool Cursors (High-Contrast Pen Symbol & Tools)
   ========================================================================== */

/* Pen Tool - Realistic High-Contrast Pen Symbol with tip at (2, 22) */
.cursor-pen,
#canvas-overlay.cursor-pen,
#canvas-container.cursor-pen #canvas-overlay {
  cursor: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='26' height='26' viewBox='0 0 24 24'%3E%3Cpath d='M18.5 2.5a2.121 2.121 0 0 1 3 3L7 19.5 2 22l2.5-5L18.5 2.5z' fill='%23ffffff' stroke='%23000000' stroke-width='2.6' stroke-linejoin='round'/%3E%3Cpath d='M18.5 2.5a2.121 2.121 0 0 1 3 3L7 19.5 2 22l2.5-5L18.5 2.5z' fill='%232563eb' stroke='%231d4ed8' stroke-width='0.8' stroke-linejoin='round'/%3E%3Cpath d='M15 6l3 3' stroke='%23ffffff' stroke-width='1.5'/%3E%3Cpath d='M5 16l3 3' stroke='%23ffffff' stroke-width='1.2'/%3E%3Cpolygon points='2,22 4.5,17 7,19.5' fill='%230f172a'/%3E%3Ccircle cx='2' cy='22' r='1.2' fill='%23000000'/%3E%3C/svg%3E") 2 22, crosshair !important;
}

/* Highlighter Cursor */
.cursor-highlighter,
#canvas-overlay.cursor-highlighter,
#canvas-container.cursor-highlighter #canvas-overlay {
  cursor: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='26' height='26' viewBox='0 0 24 24'%3E%3Cpath d='M19 3l4 4-11 11-5 1 1-5L19 3z' fill='%23ffffff' stroke='%23000000' stroke-width='2.6' stroke-linejoin='round'/%3E%3Cpath d='M19 3l4 4-11 11-5 1 1-5L19 3z' fill='%23eab308' stroke='%23ca8a04' stroke-width='0.8' stroke-linejoin='round'/%3E%3Cpath d='M6 15l4 4' stroke='%23ffffff' stroke-width='1.5'/%3E%3Ccircle cx='2' cy='22' r='1.5' fill='%23ca8a04'/%3E%3C/svg%3E") 2 22, crosshair !important;
}

/* Eraser Cursor */
.cursor-eraser,
#canvas-overlay.cursor-eraser,
#canvas-container.cursor-eraser #canvas-overlay {
  cursor: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='26' height='26' viewBox='0 0 24 24'%3E%3Crect x='4' y='5' width='16' height='13' rx='3' transform='rotate(-20 12 12)' fill='%23ffffff' stroke='%23000000' stroke-width='2.5'/%3E%3Crect x='4' y='5' width='16' height='13' rx='3' transform='rotate(-20 12 12)' fill='%23f43f5e' stroke='%23e11d48' stroke-width='0.8'/%3E%3Cpath d='M7 14l9-3.5' stroke='%23ffffff' stroke-width='2'/%3E%3C/svg%3E") 8 16, crosshair !important;
}

.cursor-grab,
#canvas-overlay.cursor-grab,
#canvas-container.cursor-grab #canvas-overlay {
  cursor: grab !important;
}

.cursor-grabbing,
#canvas-overlay.cursor-grabbing,
#canvas-container.cursor-grabbing #canvas-overlay {
  cursor: grabbing !important;
}

.cursor-crosshair,
#canvas-overlay.cursor-crosshair,
#canvas-container.cursor-crosshair #canvas-overlay {
  cursor: crosshair !important;
}

.cursor-text,
#canvas-overlay.cursor-text,
#canvas-container.cursor-text #canvas-overlay {
  cursor: text !important;
}

/* ==========================================================================
   Top Header & Navigation Bar
   ========================================================================== */

.top-navbar {
  position: absolute;
  top: 14px;
  left: 18px;
  right: 18px;
  height: 54px;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  background: var(--ui-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--ui-shadow);
  transition: var(--transition);
}

.nav-left, .nav-center, .nav-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Brand */
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 16px;
  color: var(--ui-text);
}

.brand-icon {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: linear-gradient(135deg, #2563eb, #06b6d4);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
}

.board-title-input {
  background: transparent;
  border: 1px solid transparent;
  color: var(--ui-text);
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  outline: none;
  max-width: 160px;
  transition: var(--transition);
}

.board-title-input:hover,
.board-title-input:focus {
  background: rgba(125, 125, 125, 0.1);
  border-color: var(--ui-border);
}

.save-indicator {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  color: var(--ui-text-muted);
  padding: 3px 8px;
  background: rgba(125, 125, 125, 0.08);
  border-radius: var(--radius-full);
}

.save-indicator.synced .indicator-dot {
  background-color: #10b981;
}

.save-indicator.saving .indicator-dot {
  background-color: #f59e0b;
  animation: pulse 1s infinite alternate;
}

.indicator-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: #10b981;
}

/* ==========================================================================
   PRIMARY FEATURE: Whiteboard / Blackboard Toggle Button
   ========================================================================== */

.canvas-mode-toggle-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 14px;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(6, 182, 212, 0.08));
  border: 1.5px solid var(--ui-border);
  border-radius: var(--radius-full);
  color: var(--ui-text);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  outline: none;
}

.canvas-mode-toggle-btn:hover {
  transform: translateY(-1px);
  border-color: var(--primary);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.2);
}

.canvas-mode-toggle-btn:active {
  transform: translateY(0);
}

/* Switch pill visual */
.mode-switch-track {
  width: 44px;
  height: 22px;
  background: #cbd5e1;
  border-radius: 12px;
  position: relative;
  transition: background 0.3s ease;
  display: flex;
  align-items: center;
  padding: 2px;
}

body.mode-blackboard .mode-switch-track {
  background: #000000;
  border: 1px solid #3f3f46;
}

.mode-switch-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #ffffff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), background 0.3s;
  font-size: 10px;
}

body.mode-blackboard .mode-switch-thumb {
  transform: translateX(22px);
  background: #18181b;
  color: #ffffff;
}

.mode-btn-label {
  display: flex;
  align-items: center;
  gap: 6px;
  letter-spacing: -0.01em;
}

.mode-status-badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.12);
  color: var(--primary);
  transition: var(--transition);
}

body.mode-blackboard .mode-status-badge {
  background: rgba(56, 189, 248, 0.2);
  color: #38bdf8;
}

.kbd-badge {
  font-size: 10px;
  font-family: inherit;
  font-weight: 600;
  padding: 1px 5px;
  border-radius: 4px;
  background: rgba(125, 125, 125, 0.15);
  color: var(--ui-text-muted);
}

/* ==========================================================================
   Tool Buttons & Action Controls
   ========================================================================== */

.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  background: transparent;
  color: var(--ui-text);
  cursor: pointer;
  transition: var(--transition);
}

.btn-icon:hover {
  background: rgba(125, 125, 125, 0.12);
  border-color: var(--ui-border);
}

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

.btn-icon.active {
  background: rgba(37, 99, 235, 0.15);
  color: var(--primary);
  border-color: rgba(37, 99, 235, 0.3);
}

body.mode-blackboard .btn-icon.active {
  background: rgba(56, 189, 248, 0.2);
  color: #38bdf8;
  border-color: rgba(56, 189, 248, 0.4);
}

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

/* Export Button with Dropdown */
.dropdown-container {
  position: relative;
}

.btn-export {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--primary);
  color: #ffffff;
  border: none;
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.btn-export:hover {
  background: var(--primary-hover);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 200px;
  background: var(--ui-bg-solid);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-md);
  box-shadow: var(--ui-shadow-lg);
  padding: 6px;
  display: none;
  flex-direction: column;
  gap: 4px;
  z-index: 50;
  backdrop-filter: blur(20px);
}

.dropdown-menu.show {
  display: flex;
}

.dropdown-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  color: var(--ui-text);
  font-size: 13px;
  font-weight: 500;
  border: none;
  background: transparent;
  cursor: pointer;
  text-align: left;
  width: 100%;
  transition: var(--transition);
}

.dropdown-item:hover {
  background: rgba(125, 125, 125, 0.12);
}

.dropdown-item .item-desc {
  font-size: 11px;
  color: var(--ui-text-muted);
  display: block;
}

/* ==========================================================================
   Floating Tool Palette (Left or Center)
   ========================================================================== */

.floating-tools-bar {
  position: absolute;
  top: 80px;
  left: 18px;
  z-index: 10;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 8px;
  background: var(--ui-bg);
  backdrop-filter: blur(16px);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--ui-shadow);
  transition: var(--transition);
}

.tool-separator {
  height: 1px;
  background: var(--ui-border);
  margin: 4px 2px;
}

/* Tooltip */
[data-tooltip] {
  position: relative;
}

[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  left: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%) scale(0.95);
  background: #0f172a;
  color: #ffffff;
  font-size: 11px;
  font-weight: 500;
  white-space: nowrap;
  padding: 4px 8px;
  border-radius: 4px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s, transform 0.15s;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  z-index: 99;
}

body.mode-blackboard [data-tooltip]::after {
  background: #27272a;
  border: 1px solid #3f3f46;
}

[data-tooltip]:hover::after {
  opacity: 1;
  transform: translateY(-50%) scale(1);
}

/* Shape Button Chevron Indicator */
.shape-btn-with-chevron {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.shape-chevron-indicator {
  position: absolute;
  right: 2px;
  bottom: 1px;
  font-size: 9px;
  line-height: 1;
  color: var(--ui-text-muted);
  pointer-events: none;
  opacity: 0.85;
}

/* Tool selector popup for shapes (Positioned directly beside floating toolbar) */
.shapes-popup {
  position: absolute;
  left: 76px;
  top: 195px;
  background: var(--ui-bg-solid);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--ui-shadow-lg);
  padding: 12px;
  display: none;
  flex-direction: column;
  gap: 10px;
  z-index: 100;
  width: 270px;
  animation: modalPop 0.15s cubic-bezier(0.16, 1, 0.3, 1);
}

.shapes-popup.show {
  display: flex;
}

.shapes-popup-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--ui-border);
}

.shapes-popup-title {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--ui-text-muted);
}

.shapes-close-btn {
  background: transparent;
  border: none;
  color: var(--ui-text-muted);
  font-size: 12px;
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
}

.shapes-close-btn:hover {
  background: rgba(125, 125, 125, 0.15);
  color: var(--ui-text);
}

.shapes-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 6px;
}

.shape-card {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  background: rgba(125, 125, 125, 0.05);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  color: var(--ui-text);
  font-family: inherit;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  text-align: left;
  transition: var(--transition);
}

.shape-card:hover {
  background: rgba(125, 125, 125, 0.12);
  border-color: var(--ui-border);
  transform: translateY(-1px);
}

.shape-card.active {
  background: rgba(37, 99, 235, 0.12);
  border-color: var(--primary);
  color: var(--primary);
  font-weight: 600;
}

body.mode-blackboard .shape-card.active {
  background: rgba(56, 189, 248, 0.18);
  border-color: #38bdf8;
  color: #38bdf8;
}

.shape-card-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.shape-card-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ==========================================================================
   Context Properties Bar (Colors, Width, Stroke Style)
   ========================================================================== */

.context-properties-bar {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 8px 16px;
  background: var(--ui-bg);
  backdrop-filter: blur(16px);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-full);
  box-shadow: var(--ui-shadow);
  transition: var(--transition);
}

.prop-section {
  display: flex;
  align-items: center;
  gap: 8px;
}

.prop-separator {
  width: 1px;
  height: 20px;
  background: var(--ui-border);
}

/* Color Swatches */
.color-swatches {
  display: flex;
  align-items: center;
  gap: 6px;
}

.color-swatch {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.15s, border-color 0.15s;
  position: relative;
  outline: none;
}

.color-swatch:hover {
  transform: scale(1.15);
}

.color-swatch.active {
  border-color: var(--primary);
  transform: scale(1.15);
  box-shadow: 0 0 0 2px var(--ui-bg-solid), 0 2px 6px rgba(0, 0, 0, 0.2);
}

body.mode-blackboard .color-swatch.active {
  border-color: #38bdf8;
  box-shadow: 0 0 0 2px #18181b, 0 2px 8px rgba(255, 255, 255, 0.2);
}

/* Custom Color Input */
.custom-color-wrapper {
  position: relative;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  overflow: hidden;
  border: 2px dashed var(--ui-border);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
}

.custom-color-input {
  position: absolute;
  top: -10px;
  left: -10px;
  width: 44px;
  height: 44px;
  opacity: 0;
  cursor: pointer;
}

/* Width Selectors */
.stroke-widths {
  display: flex;
  align-items: center;
  gap: 6px;
}

.width-btn {
  width: 28px;
  height: 28px;
  border-radius: 6px;
  border: 1px solid transparent;
  background: transparent;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--ui-text);
  transition: var(--transition);
}

.width-btn:hover {
  background: rgba(125, 125, 125, 0.12);
}

.width-btn.active {
  background: rgba(37, 99, 235, 0.15);
  border-color: var(--primary);
}

body.mode-blackboard .width-btn.active {
  background: rgba(56, 189, 248, 0.2);
  border-color: #38bdf8;
}

.width-dot {
  background: currentColor;
  border-radius: 50%;
}

/* Zoom Controls (Bottom Right) */
.zoom-controls {
  position: absolute;
  bottom: 24px;
  right: 18px;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 6px;
  background: var(--ui-bg);
  backdrop-filter: blur(16px);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-full);
  box-shadow: var(--ui-shadow);
}

.zoom-level-text {
  font-size: 12px;
  font-weight: 600;
  padding: 0 6px;
  min-width: 46px;
  text-align: center;
  cursor: pointer;
}

/* ==========================================================================
   Text Floating Input & Sticky Notes
   ========================================================================== */

.canvas-floating-input {
  position: absolute;
  background: transparent;
  border: 1px dashed var(--primary);
  border-radius: 4px;
  padding: 4px 8px;
  outline: none;
  font-family: var(--font-sans);
  resize: both;
  min-width: 140px;
  min-height: 40px;
  z-index: 20;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* ==========================================================================
   Modals & Toasts
   ========================================================================== */

.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 100;
  display: none;
  align-items: center;
  justify-content: center;
}

.modal-backdrop.active {
  display: flex;
}

.modal-window {
  background: var(--ui-bg-solid);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--ui-shadow-lg);
  width: 90%;
  max-width: 440px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  color: var(--ui-text);
  animation: modalPop 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalPop {
  from { opacity: 0; transform: scale(0.94); }
  to { opacity: 1; transform: scale(1); }
}

.modal-title {
  font-size: 18px;
  font-weight: 700;
}

.modal-desc {
  font-size: 14px;
  color: var(--ui-text-muted);
  line-height: 1.5;
}

.modal-textarea {
  width: 100%;
  min-height: 120px;
  background: rgba(125, 125, 125, 0.08);
  border: 1px solid var(--ui-border);
  border-radius: var(--radius-sm);
  padding: 10px;
  font-family: inherit;
  font-size: 14px;
  color: var(--ui-text);
  outline: none;
}

.modal-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
}

.btn-secondary {
  padding: 8px 16px;
  background: transparent;
  border: 1px solid var(--ui-border);
  color: var(--ui-text);
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary:hover {
  background: rgba(125, 125, 125, 0.1);
}

.btn-primary {
  padding: 8px 16px;
  background: var(--primary);
  border: none;
  color: #ffffff;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: var(--transition);
}

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

.btn-danger {
  padding: 8px 16px;
  background: #ef4444;
  border: none;
  color: #ffffff;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: var(--transition);
}

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

/* Toast Notifications */
#toast-container {
  position: fixed;
  top: 78px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  background: #0f172a;
  color: #f8fafc;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 500;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
  animation: toastIn 0.3s cubic-bezier(0.16, 1, 0.3, 1), toastOut 0.3s 2.7s forwards;
}

body.mode-blackboard .toast {
  background: #27272a;
  border: 1px solid #3f3f46;
}

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

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

@keyframes pulse {
  0% { opacity: 0.4; }
  100% { opacity: 1; }
}

/* ==========================================================================
   User Profile Badge & Authentication Modals
   ========================================================================== */

.btn-user-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  border: 1px solid var(--ui-border);
  background: rgba(125, 125, 125, 0.08);
  color: var(--ui-text);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.btn-user-badge:hover {
  background: rgba(125, 125, 125, 0.15);
  border-color: var(--primary);
}

.user-avatar-circle {
  font-size: 13px;
}

/* Fullscreen Lock Screen Modal */
.lock-screen-modal {
  z-index: 99999 !important;
  backdrop-filter: blur(24px) saturate(140%) !important;
  -webkit-backdrop-filter: blur(24px) saturate(140%) !important;
  background: rgba(15, 23, 42, 0.75) !important;
}

body.mode-blackboard .lock-screen-modal {
  background: rgba(0, 0, 0, 0.85) !important;
}

.auth-modal-window {
  max-width: 390px;
  width: 90%;
  padding: 30px;
  text-align: center;
  border-radius: 18px;
  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.4);
}

.auth-header {
  margin-bottom: 20px;
}

.auth-title {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--ui-text);
}

.auth-subtitle {
  font-size: 13px;
  color: var(--ui-text-muted);
  line-height: 1.45;
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 14px;
  text-align: left;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--ui-text-muted);
}

.form-input {
  width: 100%;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--ui-border);
  background: rgba(125, 125, 125, 0.08);
  color: var(--ui-text);
  font-family: inherit;
  font-size: 14px;
  outline: none;
  transition: var(--transition);
}

.form-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
  background: var(--ui-bg-solid);
}

.form-row-checkbox {
  display: flex;
  align-items: center;
  font-size: 13px;
}

.checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  color: var(--ui-text-muted);
  user-select: none;
}

.btn-auth-submit {
  width: 100%;
  padding: 11px;
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--radius-md);
  margin-top: 4px;
}

.auth-error-banner {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: rgba(239, 68, 68, 0.15);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: #ef4444;
  font-size: 12px;
  font-weight: 500;
  margin-bottom: 12px;
  text-align: center;
}

.auth-success-banner {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #10b981;
  font-size: 12px;
  font-weight: 500;
  margin-bottom: 12px;
  text-align: center;
}

.auth-footer-hint {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--ui-border);
  font-size: 12px;
  color: var(--ui-text-muted);
  line-height: 1.4;
}