/* Scientific Calculator — SmarterSources */

.calc-wrapper {
  max-width: 420px;
  margin: 0 auto;
}

/* --- Style Selector (Accordion) --- */
.calc-style-selector {
  max-width: 420px;
  margin: 0 auto 12px;
}

.calc-style-header {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  border: 1px solid var(--color-border, #e2e8f0);
  border-radius: var(--radius-sm, 6px);
  background: var(--color-surface, #fff);
  font-family: var(--font-body);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--color-text-secondary, #64748b);
  cursor: pointer;
  transition: all 0.15s;
}

.calc-style-header:hover {
  border-color: var(--color-primary-subtle, #bac8ff);
  color: var(--color-text, #1e293b);
}

.calc-style-chevron {
  transition: transform 0.25s ease;
}

.calc-style-selector.open .calc-style-chevron {
  transform: rotate(180deg);
}

.calc-style-options {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin-top: 0;
  transition: max-height 0.3s ease, opacity 0.2s ease, margin-top 0.3s ease;
}

.calc-style-selector.open .calc-style-options {
  max-height: 80px;
  opacity: 1;
  margin-top: 10px;
}

.calc-style-btn {
  padding: 7px 14px;
  border: 2px solid var(--color-border, #e2e8f0);
  border-radius: 999px;
  background: var(--color-surface, #fff);
  font-family: var(--font-body);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--color-text-muted, #94a3b8);
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}

.calc-style-btn:hover {
  border-color: var(--color-primary-subtle, #bac8ff);
  color: var(--color-text, #1e293b);
}

.calc-style-btn.active {
  border-color: var(--color-primary, #3b5bdb);
  background: var(--color-primary-light, #edf2ff);
  color: var(--color-primary, #3b5bdb);
}

/* Theme-specific active colours */
.calc-style-btn[data-style="dark"].active { border-color: #334155; background: #f1f5f9; color: #1e293b; }
.calc-style-btn[data-style="retro"].active { border-color: #16a34a; background: #f0fdf4; color: #15803d; }
.calc-style-btn[data-style="pastel"].active { border-color: #ec4899; background: #fdf2f8; color: #db2777; }
.calc-style-btn[data-style="contrast"].active { border-color: #1e293b; background: #fefce8; color: #1e293b; }

/* --- Display --- */
.calc-display {
  background: #1e293b;
  border-radius: var(--radius-md, 10px) var(--radius-md, 10px) 0 0;
  padding: 20px 18px 16px;
  min-height: 110px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  position: relative;
  overflow: hidden;
  transition: background 0.3s;
}

.calc-mode-indicator {
  position: absolute;
  top: 10px;
  left: 14px;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #94a3b8;
  padding: 2px 8px;
  border: 1px solid #334155;
  border-radius: 4px;
  background: rgba(255,255,255,0.05);
  transition: color 0.3s, border-color 0.3s, background 0.3s;
}

.calc-memory-indicator {
  position: absolute;
  top: 10px;
  right: 14px;
  font-size: 0.7rem;
  font-weight: 700;
  color: #60a5fa;
  opacity: 0;
  transition: opacity 0.2s;
}

.calc-memory-indicator.visible {
  opacity: 1;
}

.calc-expr {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.88rem;
  color: #94a3b8;
  text-align: right;
  min-height: 1.2em;
  word-break: break-all;
  line-height: 1.4;
  margin-bottom: 6px;
  transition: color 0.3s;
}

.calc-result {
  font-family: 'JetBrains Mono', monospace;
  font-size: 2.2rem;
  font-weight: 500;
  color: #f1f5f9;
  text-align: right;
  word-break: break-all;
  line-height: 1.2;
  min-height: 1.2em;
  transition: color 0.3s;
}

.calc-result.error {
  color: #f87171;
  font-size: 1.1rem;
}

.calc-copy-btn {
  position: absolute;
  bottom: 14px;
  left: 14px;
  padding: 4px 10px;
  border: 1px solid #334155;
  border-radius: 4px;
  background: transparent;
  color: #64748b;
  font-size: 0.72rem;
  font-family: var(--font-body);
  cursor: pointer;
  transition: all 0.15s;
}

.calc-copy-btn:hover {
  border-color: #60a5fa;
  color: #60a5fa;
}

/* --- Button Grid --- */
.calc-buttons {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 2px;
  background: #334155;
  border-radius: 0 0 var(--radius-md, 10px) var(--radius-md, 10px);
  overflow: hidden;
  border: 2px solid #334155;
  border-top: none;
  transition: background 0.3s, border-color 0.3s;
}

.calc-btn {
  padding: 14px 4px;
  border: none;
  font-family: var(--font-body);
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.08s, color 0.15s;
  text-align: center;
  user-select: none;
  line-height: 1.2;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.calc-btn:active {
  transform: scale(0.94);
}

/* Number buttons */
.calc-btn-num {
  background: #f8fafc;
  color: #1e293b;
}
.calc-btn-num:hover { background: #e2e8f0; }

/* Operator buttons */
.calc-btn-op {
  background: #dbeafe;
  color: #1e40af;
}
.calc-btn-op:hover { background: #bfdbfe; }

/* Scientific function buttons */
.calc-btn-fn {
  background: #e2e8f0;
  color: #475569;
  font-size: 0.78rem;
}
.calc-btn-fn:hover { background: #cbd5e1; }

/* Equals */
.calc-btn-eq {
  background: var(--color-primary, #3b5bdb);
  color: #fff;
  font-size: 1.1rem;
}
.calc-btn-eq:hover { background: var(--color-primary-hover, #364fc7); }

/* Clear / Delete */
.calc-btn-clear {
  background: #fef2f2;
  color: #dc2626;
  font-size: 0.82rem;
}
.calc-btn-clear:hover { background: #fecaca; }

/* Memory */
.calc-btn-mem {
  background: #f0f9ff;
  color: #0369a1;
  font-size: 0.76rem;
}
.calc-btn-mem:hover { background: #e0f2fe; }

/* Wide button */
.calc-btn-wide {
  grid-column: span 2;
}

/* ================================================================
   THEME: Dark
   ================================================================ */
.calc-wrapper[data-style="dark"] .calc-display {
  background: #0f0f0f;
}
.calc-wrapper[data-style="dark"] .calc-mode-indicator {
  color: #666;
  border-color: #333;
  background: rgba(255,255,255,0.03);
}
.calc-wrapper[data-style="dark"] .calc-expr { color: #777; }
.calc-wrapper[data-style="dark"] .calc-result { color: #e0e0e0; }
.calc-wrapper[data-style="dark"] .calc-copy-btn {
  border-color: #333;
  color: #555;
}
.calc-wrapper[data-style="dark"] .calc-copy-btn:hover {
  border-color: #888;
  color: #aaa;
}
.calc-wrapper[data-style="dark"] .calc-buttons {
  background: #1a1a1a;
  border-color: #1a1a1a;
}
.calc-wrapper[data-style="dark"] .calc-btn-num {
  background: #2a2a2a;
  color: #e0e0e0;
}
.calc-wrapper[data-style="dark"] .calc-btn-num:hover { background: #353535; }
.calc-wrapper[data-style="dark"] .calc-btn-op {
  background: #1e3a5f;
  color: #7cb3f0;
}
.calc-wrapper[data-style="dark"] .calc-btn-op:hover { background: #264a72; }
.calc-wrapper[data-style="dark"] .calc-btn-fn {
  background: #222;
  color: #999;
}
.calc-wrapper[data-style="dark"] .calc-btn-fn:hover { background: #2d2d2d; }
.calc-wrapper[data-style="dark"] .calc-btn-eq {
  background: #2563eb;
  color: #fff;
}
.calc-wrapper[data-style="dark"] .calc-btn-eq:hover { background: #1d4ed8; }
.calc-wrapper[data-style="dark"] .calc-btn-clear {
  background: #3a1a1a;
  color: #f87171;
}
.calc-wrapper[data-style="dark"] .calc-btn-clear:hover { background: #4a2020; }
.calc-wrapper[data-style="dark"] .calc-btn-mem {
  background: #1a2a3a;
  color: #60a5fa;
}
.calc-wrapper[data-style="dark"] .calc-btn-mem:hover { background: #223548; }
.calc-wrapper[data-style="dark"] .calc-memory-indicator { color: #60a5fa; }

/* ================================================================
   THEME: Retro (green LCD terminal)
   ================================================================ */
.calc-wrapper[data-style="retro"] .calc-display {
  background: #0a0a0a;
  border: 2px solid #1a3a1a;
  border-bottom: none;
}
.calc-wrapper[data-style="retro"] .calc-mode-indicator {
  color: #33cc33;
  border-color: #1a3a1a;
  background: transparent;
  font-family: 'JetBrains Mono', monospace;
}
.calc-wrapper[data-style="retro"] .calc-expr {
  color: #1a7a1a;
}
.calc-wrapper[data-style="retro"] .calc-result {
  color: #33ff33;
  text-shadow: 0 0 8px rgba(51, 255, 51, 0.3);
}
.calc-wrapper[data-style="retro"] .calc-result.error {
  color: #ff4444;
  text-shadow: 0 0 8px rgba(255, 68, 68, 0.3);
}
.calc-wrapper[data-style="retro"] .calc-copy-btn {
  border-color: #1a3a1a;
  color: #2a8a2a;
}
.calc-wrapper[data-style="retro"] .calc-copy-btn:hover {
  border-color: #33cc33;
  color: #33cc33;
}
.calc-wrapper[data-style="retro"] .calc-buttons {
  background: #111;
  border-color: #1a3a1a;
}
.calc-wrapper[data-style="retro"] .calc-btn-num {
  background: #1a1a1a;
  color: #33cc33;
  font-family: 'JetBrains Mono', monospace;
}
.calc-wrapper[data-style="retro"] .calc-btn-num:hover { background: #252525; }
.calc-wrapper[data-style="retro"] .calc-btn-op {
  background: #0d2a0d;
  color: #44dd44;
}
.calc-wrapper[data-style="retro"] .calc-btn-op:hover { background: #153515; }
.calc-wrapper[data-style="retro"] .calc-btn-fn {
  background: #151515;
  color: #22aa22;
}
.calc-wrapper[data-style="retro"] .calc-btn-fn:hover { background: #1e1e1e; }
.calc-wrapper[data-style="retro"] .calc-btn-eq {
  background: #1a6a1a;
  color: #ccffcc;
}
.calc-wrapper[data-style="retro"] .calc-btn-eq:hover { background: #228822; }
.calc-wrapper[data-style="retro"] .calc-btn-clear {
  background: #2a1111;
  color: #ff6666;
}
.calc-wrapper[data-style="retro"] .calc-btn-clear:hover { background: #3a1818; }
.calc-wrapper[data-style="retro"] .calc-btn-mem {
  background: #111a11;
  color: #55bb55;
}
.calc-wrapper[data-style="retro"] .calc-btn-mem:hover { background: #1a2a1a; }
.calc-wrapper[data-style="retro"] .calc-memory-indicator { color: #33ff33; }

/* ================================================================
   THEME: Pastel
   ================================================================ */
.calc-wrapper[data-style="pastel"] .calc-display {
  background: #fdf2f8;
  border: 2px solid #f9a8d4;
  border-bottom: none;
}
.calc-wrapper[data-style="pastel"] .calc-mode-indicator {
  color: #be185d;
  border-color: #f9a8d4;
  background: rgba(255,255,255,0.5);
}
.calc-wrapper[data-style="pastel"] .calc-expr {
  color: #9d7ab0;
}
.calc-wrapper[data-style="pastel"] .calc-result {
  color: #831843;
}
.calc-wrapper[data-style="pastel"] .calc-result.error {
  color: #e11d48;
}
.calc-wrapper[data-style="pastel"] .calc-copy-btn {
  border-color: #f9a8d4;
  color: #be185d;
}
.calc-wrapper[data-style="pastel"] .calc-copy-btn:hover {
  border-color: #ec4899;
  color: #ec4899;
}
.calc-wrapper[data-style="pastel"] .calc-buttons {
  background: #fbcfe8;
  border-color: #f9a8d4;
}
.calc-wrapper[data-style="pastel"] .calc-btn-num {
  background: #fff1f5;
  color: #4a1942;
}
.calc-wrapper[data-style="pastel"] .calc-btn-num:hover { background: #ffe4ee; }
.calc-wrapper[data-style="pastel"] .calc-btn-op {
  background: #e9d5ff;
  color: #6b21a8;
}
.calc-wrapper[data-style="pastel"] .calc-btn-op:hover { background: #d8b4fe; }
.calc-wrapper[data-style="pastel"] .calc-btn-fn {
  background: #fce7f3;
  color: #9d174d;
}
.calc-wrapper[data-style="pastel"] .calc-btn-fn:hover { background: #fbcfe8; }
.calc-wrapper[data-style="pastel"] .calc-btn-eq {
  background: #ec4899;
  color: #fff;
}
.calc-wrapper[data-style="pastel"] .calc-btn-eq:hover { background: #db2777; }
.calc-wrapper[data-style="pastel"] .calc-btn-clear {
  background: #fef3c7;
  color: #d97706;
}
.calc-wrapper[data-style="pastel"] .calc-btn-clear:hover { background: #fde68a; }
.calc-wrapper[data-style="pastel"] .calc-btn-mem {
  background: #dbeafe;
  color: #1d4ed8;
}
.calc-wrapper[data-style="pastel"] .calc-btn-mem:hover { background: #bfdbfe; }
.calc-wrapper[data-style="pastel"] .calc-memory-indicator { color: #ec4899; }

/* ================================================================
   THEME: High Contrast
   ================================================================ */
.calc-wrapper[data-style="contrast"] .calc-display {
  background: #000;
  border: 3px solid #fff;
  border-bottom: none;
}
.calc-wrapper[data-style="contrast"] .calc-mode-indicator {
  color: #ffff00;
  border-color: #ffff00;
  background: transparent;
  font-weight: 800;
}
.calc-wrapper[data-style="contrast"] .calc-expr {
  color: #cccccc;
}
.calc-wrapper[data-style="contrast"] .calc-result {
  color: #ffffff;
  font-weight: 700;
}
.calc-wrapper[data-style="contrast"] .calc-result.error {
  color: #ff0000;
}
.calc-wrapper[data-style="contrast"] .calc-copy-btn {
  border-color: #fff;
  color: #fff;
  font-weight: 700;
}
.calc-wrapper[data-style="contrast"] .calc-copy-btn:hover {
  border-color: #ffff00;
  color: #ffff00;
}
.calc-wrapper[data-style="contrast"] .calc-buttons {
  background: #fff;
  border: 3px solid #fff;
  border-top: none;
}
.calc-wrapper[data-style="contrast"] .calc-btn-num {
  background: #fff;
  color: #000;
  font-weight: 800;
  font-size: 1rem;
}
.calc-wrapper[data-style="contrast"] .calc-btn-num:hover { background: #e0e0e0; }
.calc-wrapper[data-style="contrast"] .calc-btn-op {
  background: #ffff00;
  color: #000;
  font-weight: 800;
}
.calc-wrapper[data-style="contrast"] .calc-btn-op:hover { background: #e6e600; }
.calc-wrapper[data-style="contrast"] .calc-btn-fn {
  background: #ddd;
  color: #000;
  font-weight: 700;
}
.calc-wrapper[data-style="contrast"] .calc-btn-fn:hover { background: #c0c0c0; }
.calc-wrapper[data-style="contrast"] .calc-btn-eq {
  background: #0000ff;
  color: #fff;
  font-weight: 800;
  font-size: 1.2rem;
}
.calc-wrapper[data-style="contrast"] .calc-btn-eq:hover { background: #0000cc; }
.calc-wrapper[data-style="contrast"] .calc-btn-clear {
  background: #ff0000;
  color: #fff;
  font-weight: 800;
}
.calc-wrapper[data-style="contrast"] .calc-btn-clear:hover { background: #cc0000; }
.calc-wrapper[data-style="contrast"] .calc-btn-mem {
  background: #e0e0ff;
  color: #000;
  font-weight: 700;
}
.calc-wrapper[data-style="contrast"] .calc-btn-mem:hover { background: #c0c0ff; }
.calc-wrapper[data-style="contrast"] .calc-memory-indicator { color: #ffff00; }

/* --- History --- */
.calc-history {
  margin-top: 24px;
}

.calc-history-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  padding: 10px 0;
}

.calc-history-header h3 {
  margin: 0;
  font-size: 0.95rem;
  color: var(--color-text);
}

.calc-history-toggle {
  font-size: 0.8rem;
  color: var(--color-text-muted, #94a3b8);
  border: none;
  background: none;
  cursor: pointer;
  padding: 4px 8px;
  font-family: var(--font-body);
}

.calc-history-list {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.calc-history-list.visible {
  max-height: 600px;
  overflow-y: auto;
}

.calc-history-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border-light, #f1f5f9);
  cursor: pointer;
  transition: background 0.1s;
  border-radius: 4px;
  padding-left: 6px;
  padding-right: 6px;
}

.calc-history-item:hover {
  background: var(--color-primary-light, #edf2ff);
}

.calc-history-expr {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.8rem;
  color: var(--color-text-secondary, #64748b);
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.calc-history-result {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-text, #1e293b);
  margin-left: 12px;
  white-space: nowrap;
}

.calc-history-clear {
  padding: 6px 12px;
  border: 1px solid var(--color-border, #e2e8f0);
  border-radius: var(--radius-sm, 6px);
  background: var(--color-bg, #fff);
  font-family: var(--font-body);
  font-size: 0.78rem;
  color: var(--color-text-muted, #94a3b8);
  cursor: pointer;
  margin-top: 8px;
  transition: all 0.15s;
}

.calc-history-clear:hover {
  border-color: #fca5a5;
  color: #dc2626;
  background: #fef2f2;
}

/* Toast */
.calc-toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  padding: 10px 20px;
  background: #1e293b;
  color: #fff;
  border-radius: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  opacity: 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
  z-index: 9999;
  pointer-events: none;
}

.calc-toast.visible {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* --- Responsive --- */
@media (max-width: 480px) {
  .calc-wrapper {
    max-width: 100%;
  }
  .calc-btn {
    padding: 12px 2px;
    font-size: 0.82rem;
    min-height: 44px;
  }
  .calc-btn-fn {
    font-size: 0.72rem;
  }
  .calc-result {
    font-size: 1.8rem;
  }
  .calc-style-selector {
    max-width: 100%;
  }
  .calc-style-options {
    gap: 6px;
  }
  .calc-style-btn {
    padding: 5px 10px;
    font-size: 0.72rem;
  }
}