/* ==========================================================================
   SHARED UI COMPONENTS: BASIC CALC, PROGRAMMER, KNOWLEDGE HUB DRAWER
   ========================================================================== */

/* 1. Basic Commercial Desktop Calculator */
.basic-calc-container {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem 1rem;
}

.basic-calc-chassis {
  width: 100%;
  max-width: 360px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.basic-display-box {
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  min-height: 85px;
  justify-content: space-between;
}

.basic-history-line {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  min-height: 1.2rem;
}

.basic-memory-flag {
  font-size: 0.7rem;
  font-weight: 800;
  color: var(--accent-primary);
  align-self: flex-start;
}

.basic-main-line {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.1;
  word-break: break-all;
}

.basic-keypad-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.basic-btn {
  height: 52px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-surface);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 1.15rem;
  font-weight: 600;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all var(--transition-fast);
  user-select: none;
  position: relative;
}

.basic-btn:hover {
  background-color: var(--bg-subtle);
  border-color: var(--border-hover);
  transform: translateY(-1.5px);
  box-shadow: 0 4px 10px -2px rgba(0, 0, 0, 0.08);
}

.basic-btn:active {
  transform: translateY(1px) scale(0.96);
  box-shadow: none;
}

.basic-btn.op-btn {
  background-color: var(--accent-light);
  color: var(--accent-primary);
  border-color: var(--accent-border);
  font-weight: 700;
}

.basic-btn.op-btn:hover {
  background-color: var(--accent-primary);
  color: #ffffff;
  box-shadow: 0 4px 12px -2px var(--accent-glow);
}

.basic-btn.equal-btn {
  background: linear-gradient(135deg, var(--accent-primary) 0%, #4338ca 100%);
  color: #ffffff;
  border-color: var(--accent-primary);
  font-weight: 800;
  box-shadow: 0 4px 12px -2px var(--accent-glow);
}

.basic-btn.equal-btn:hover {
  background: linear-gradient(135deg, var(--accent-hover) 0%, var(--accent-primary) 100%);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px -2px var(--accent-glow);
}

.basic-btn.clear-btn {
  color: #ef4444;
}

.basic-btn.clear-btn:hover {
  background-color: rgba(239, 68, 68, 0.1);
  border-color: rgba(239, 68, 68, 0.3);
}

/* 2. Programmer 64-Bit Bitboard & Hex/Dec/Oct/Bin */
.programmer-container {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.prog-display-panel {
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.prog-base-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.9rem;
}

.prog-base-label {
  width: 45px;
  font-weight: 800;
  color: var(--text-muted);
  font-size: 0.75rem;
}

.prog-base-val {
  font-weight: 700;
  color: var(--text-primary);
  word-break: break-all;
  flex: 1;
}

/* 64-Bit Interactive Bitboard */
.bitboard-wrapper {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.bitboard-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
}

.bitboard-grid {
  display: grid;
  grid-template-columns: repeat(16, 1fr);
  gap: 4px;
}

@media (max-width: 768px) {
  .bitboard-grid {
    grid-template-columns: repeat(8, 1fr);
  }
}

.bit-cell {
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  height: 38px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  user-select: none;
  position: relative;
}

.bit-cell:hover {
  border-color: var(--accent-primary);
  transform: scale(1.15);
  box-shadow: 0 0 10px var(--accent-light);
  z-index: 2;
}

.bit-cell.bit-1 {
  background-color: var(--accent-light);
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  font-weight: 800;
  box-shadow: 0 0 8px -2px var(--accent-glow);
}

.bit-val {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1;
}

.bit-index {
  font-size: 0.55rem;
  color: var(--text-muted);
  line-height: 1;
  margin-top: 2px;
}

/* 3. Educational Knowledge Hub & Formula Drawer */
.knowledge-drawer-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(8px);
  z-index: 100;
  display: none;
  justify-content: flex-end;
}

.knowledge-drawer-overlay.open {
  display: flex;
}

.knowledge-drawer {
  width: 100%;
  max-width: 520px;
  height: 100%;
  background-color: var(--bg-surface);
  border-left: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  box-shadow: -10px 0 25px rgba(0, 0, 0, 0.15);
  animation: slideInRight 0.25s ease-out;
}

@keyframes slideInRight {
  from { transform: translateX(100%); }
  to { transform: translateX(0); }
}

.drawer-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.drawer-title {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-primary);
}

.drawer-close-btn {
  background: transparent;
  border: none;
  font-size: 1.35rem;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
}
.drawer-close-btn:hover { color: var(--text-primary); }

.drawer-content {
  padding: 1.5rem;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.info-section {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.info-section-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-primary);
}

.info-text {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.formula-card {
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-primary);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.formula-name {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-muted);
}