/* ==========================================================================
   Project OmniCalc - Calculator Engines & Interactive Tool Styles
   Desmos-Grade Keypad, Glassmorphism Displays & Interactive Components
   ========================================================================== */

/* Main Calculator Container */
.calculator-app-card {
  background-color: var(--bg-elevated);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  max-width: 580px;
  margin: 0 auto 2.5rem;
  transition: all var(--transition-normal);
  position: relative;
}

/* Calculator Top Bar & Mode Toggles */
.calc-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.25rem 0.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

.mode-toggle-group {
  display: inline-flex;
  align-items: center;
  background-color: var(--bg-tertiary);
  padding: 3px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
}

.mode-pill {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 6px;
  color: var(--text-muted);
  transition: all var(--transition-fast);
}

.mode-pill.active {
  background-color: var(--bg-secondary);
  color: var(--accent-primary);
  box-shadow: var(--shadow-sm);
}

.calc-action-btns {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.calc-btn-sm {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 5px 9px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
}

.calc-btn-sm:hover {
  color: var(--text-primary);
  border-color: var(--accent-primary);
}

.calc-btn-sm.active {
  background-color: var(--accent-primary-light);
  color: var(--accent-primary);
  border-color: var(--accent-primary);
}

/* Screen / Display Area */
.calc-screen {
  padding: 1.25rem 1.5rem;
  background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
  border-bottom: 1px solid var(--border-color);
  text-align: right;
  min-height: 120px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  position: relative;
}

.calc-expression-wrap {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  color: var(--text-muted);
  min-height: 1.75rem;
  word-break: break-all;
  overflow-x: auto;
  white-space: nowrap;
  scrollbar-width: none;
  margin-bottom: 0.5rem;
  letter-spacing: 0.02em;
}

.calc-expression-wrap::-webkit-scrollbar {
  display: none;
}

.calc-result-wrap {
  display: flex;
  align-items: baseline;
  justify-content: flex-end;
  gap: 0.5rem;
}

.calc-equals-symbol {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  color: var(--accent-primary);
  opacity: 0.8;
}

.calc-result-text {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.1;
  word-break: break-all;
  overflow-x: auto;
  white-space: nowrap;
  scrollbar-width: none;
  transition: font-size 0.15s ease;
  user-select: all;
}

.calc-result-text::-webkit-scrollbar {
  display: none;
}

/* Quick Copy Trigger */
.copy-badge-btn {
  position: absolute;
  top: 10px;
  right: 14px;
  opacity: 0;
  transform: translateY(-4px);
  font-size: 0.7rem;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
}

.calc-screen:hover .copy-badge-btn {
  opacity: 1;
  transform: translateY(0);
}

.copy-badge-btn:hover {
  background: var(--accent-primary);
  color: #fff;
  border-color: var(--accent-primary);
}

/* Keypad Section */
.calc-keypad {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.keypad-row {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.6rem;
}

/* Keypad Buttons */
.k-btn {
  height: 52px;
  border-radius: var(--radius-md);
  font-size: 1.15rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.12s cubic-bezier(0.4, 0, 0.2, 1);
  user-select: none;
  border: 1px solid transparent;
  box-shadow: var(--shadow-sm);
}

.k-btn:active {
  transform: scale(0.94);
  box-shadow: none;
}

/* Key Types */
.k-num {
  background-color: var(--key-num-bg);
  color: var(--key-num-text);
  border-color: var(--border-color);
  font-weight: 600;
}
.k-num:hover {
  background-color: var(--key-num-hover);
  border-color: var(--accent-primary);
}

.k-fn {
  background-color: var(--key-fn-bg);
  color: var(--key-fn-text);
  font-size: 0.95rem;
  font-family: var(--font-sans);
}
.k-fn:hover {
  background-color: var(--key-fn-hover);
  color: var(--text-primary);
}

.k-op {
  background-color: var(--key-op-bg);
  color: var(--key-op-text);
  font-size: 1.35rem;
}
.k-op:hover {
  background-color: var(--key-op-hover);
}

.k-equal {
  background-color: var(--key-equal-bg);
  color: var(--key-equal-text);
  font-size: 1.5rem;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.35);
}
.k-equal:hover {
  background-color: var(--key-equal-hover);
  box-shadow: 0 6px 16px rgba(79, 70, 229, 0.45);
}

.k-danger {
  background-color: var(--key-danger-bg);
  color: var(--key-danger-text);
  font-weight: 700;
}
.k-danger:hover {
  filter: brightness(0.95);
}

/* History Side Panel Drawer */
.history-drawer {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 100%;
  max-width: 320px;
  background-color: var(--bg-secondary);
  border-left: 1px solid var(--border-color);
  box-shadow: -8px 0 24px rgba(0, 0, 0, 0.2);
  z-index: 20;
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform var(--transition-normal);
}

.history-drawer.open {
  transform: translateX(0);
}

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

.history-header h4 {
  font-size: 0.95rem;
  font-weight: 700;
}

.history-list {
  flex: 1;
  overflow-y: auto;
  padding: 0.75rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.history-item {
  padding: 0.75rem;
  border-radius: var(--radius-md);
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: right;
}

.history-item:hover {
  border-color: var(--accent-primary);
  background-color: var(--bg-primary);
}

.history-exp {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
  word-break: break-all;
}

.history-res {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.history-empty {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
  margin: 3rem auto;
}

/* ==========================================================================
   Specialized Calculators (Percent, Units, Fraction)
   ========================================================================== */
.specialized-card {
  max-width: 820px;
  margin: 0 auto 3rem;
  background-color: var(--bg-elevated);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  padding: 2rem;
}

.spec-calc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.calc-box-item {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.calc-box-item:hover {
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-md);
}

.calc-box-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-primary);
}

.calc-input-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.c-input {
  flex: 1;
  min-width: 90px;
  height: 44px;
  padding: 0 0.85rem;
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 600;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  outline: none;
  transition: all var(--transition-fast);
}

.c-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px var(--accent-primary-light);
  background-color: var(--bg-secondary);
}

.c-select {
  height: 44px;
  padding: 0 1rem;
  font-size: 0.95rem;
  font-weight: 600;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  outline: none;
  cursor: pointer;
}

.c-select:focus {
  border-color: var(--accent-primary);
}

.calc-output-box {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem;
  text-align: right;
  margin-top: auto;
}

.calc-output-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
}

.calc-output-value {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent-primary);
  word-break: break-all;
}

/* Fraction Calculator Specifics */
.fraction-ui-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin: 1.5rem 0;
  flex-wrap: wrap;
}

.fraction-box {
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 90px;
}

.fraction-divider {
  height: 3px;
  background-color: var(--text-primary);
  border-radius: 2px;
}

.fraction-op-select {
  font-size: 1.4rem;
  font-weight: 800;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  color: var(--accent-primary);
}

/* Unit Converter Converter Row */
.unit-converter-wrap {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.unit-row {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 0.75rem;
  align-items: center;
}

.unit-swap-btn {
  align-self: center;
  margin: -0.5rem auto;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-fast);
}

.unit-swap-btn:hover {
  transform: rotate(180deg);
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

@media (max-width: 580px) {
  .calc-screen {
    min-height: 100px;
    padding: 1rem;
  }
  .calc-result-text {
    font-size: 2rem;
  }
  .calc-keypad {
    padding: 0.75rem;
    gap: 0.5rem;
  }
  .keypad-row {
    gap: 0.4rem;
  }
  .k-btn {
    height: 48px;
    font-size: 1rem;
  }
  .specialized-card {
    padding: 1.25rem;
  }
  .spec-calc-grid {
    grid-template-columns: 1fr;
  }
}