/* Chemistry Lab Styles */
.lab-layout {
  display: grid;
  grid-template-columns: 260px 1fr 280px;
  gap: var(--space-4);
  align-items: start;
}

@media (max-width: 1024px) {
  .lab-layout { grid-template-columns: 1fr; }
}

/* Elements Panel */
.elements-panel { max-height: 80vh; overflow-y: auto; }
.panel-title { font-size: 1rem; margin-bottom: var(--space-3); font-weight: 700; }
.element-search-box { margin-bottom: var(--space-3); }
.element-categories {
  display: flex; flex-wrap: wrap; gap: 4px; margin-bottom: var(--space-3);
}
.cat-btn {
  padding: 3px 10px; font-size: .7rem; border-radius: var(--radius-full);
  background: var(--color-surface-alt); border: 1px solid var(--color-border);
  color: var(--color-text); cursor: pointer; transition: all .2s;
}
.cat-btn.active, .cat-btn:hover {
  background: var(--color-primary); color: #fff; border-color: var(--color-primary);
}
.elements-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px;
}
.element-tile {
  padding: 8px 4px; text-align: center; border-radius: var(--radius-md);
  border: 2px solid var(--color-border); cursor: pointer; transition: all .2s;
  background: var(--color-surface); position: relative; overflow: hidden;
  user-select: none; -webkit-user-select: none;
}
.element-tile:hover {
  border-color: var(--color-primary); transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(99,102,241,.3);
}
.element-tile.selected {
  border-color: var(--color-accent); background: rgba(99,102,241,.15);
  box-shadow: 0 0 12px rgba(99,102,241,.4);
}
.element-tile.metals { border-left: 3px solid #f59e0b; }
.element-tile.nonmetals { border-left: 3px solid #22c55e; }
.element-tile.acids { border-left: 3px solid #ef4444; }
.element-tile.bases { border-left: 3px solid #3b82f6; }
.element-tile.compounds { border-left: 3px solid #a855f7; }
.el-symbol { font-size: 1.3rem; font-weight: 900; display: block; line-height: 1.2; }
.el-name { font-size: .55rem; color: var(--color-text-secondary); display: block; }

/* Mixing Area */
.mixing-area { text-align: center; }
.beaker-container {
  display: flex; justify-content: center; align-items: flex-end;
  height: 280px; margin: var(--space-4) 0;
}
.beaker {
  width: 180px; height: 240px; position: relative;
  border: 3px solid rgba(255,255,255,.25); border-top: none;
  border-radius: 0 0 20px 20px; background: rgba(255,255,255,.03);
  overflow: hidden; transition: border-color .3s;
}
.beaker::before {
  content: ''; position: absolute; top: -3px; left: -20px; right: -20px;
  height: 6px; background: rgba(255,255,255,.25); border-radius: 3px;
}
.beaker-liquid {
  position: absolute; bottom: 0; left: 0; right: 0; height: 0;
  background: linear-gradient(180deg, rgba(99,102,241,.4), rgba(99,102,241,.7));
  transition: all .8s cubic-bezier(.4,0,.2,1); border-radius: 0 0 17px 17px;
}
.beaker-liquid.heating {
  animation: boil 0.3s ease-in-out infinite alternate;
}
@keyframes boil {
  0% { transform: translateY(0); }
  100% { transform: translateY(-3px); }
}
.beaker-bubbles {
  position: absolute; bottom: 0; left: 0; right: 0; height: 100%;
  pointer-events: none; overflow: hidden;
}
.bubble {
  position: absolute; border-radius: 50%; background: rgba(255,255,255,.3);
  animation: bubbleUp 1.5s ease-in infinite;
}
@keyframes bubbleUp {
  0% { opacity: 0; transform: translateY(0) scale(0.5); }
  20% { opacity: 1; }
  100% { opacity: 0; transform: translateY(-200px) scale(1.2); }
}
.beaker-label {
  position: absolute; inset: 0; display: flex; align-items: center;
  justify-content: center; font-size: .8rem; color: var(--color-text-secondary);
  text-align: center; padding: 12px; pointer-events: none;
}
.beaker.has-elements .beaker-label { opacity: 0; }

.selected-elements {
  display: flex; flex-wrap: wrap; gap: 6px; justify-content: center;
  margin: var(--space-3) 0; min-height: 32px;
}
.element-chip {
  padding: 4px 12px; border-radius: var(--radius-full);
  background: var(--color-primary); color: #fff; font-size: .8rem;
  font-weight: 600; display: flex; align-items: center; gap: 4px;
  animation: chipIn .3s ease;
}
@keyframes chipIn {
  from { transform: scale(0); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}
.element-chip .remove-chip {
  cursor: pointer; opacity: .7; font-size: .7rem;
}
.element-chip .remove-chip:hover { opacity: 1; }

.mix-controls {
  display: flex; gap: var(--space-2); justify-content: center; flex-wrap: wrap;
}
.btn-lg { padding: 12px 28px; font-size: 1.1rem; }

/* Reaction Result */
.reaction-result { animation: resultIn .5s ease; }
@keyframes resultIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
.result-header {
  display: flex; align-items: center; justify-content: space-between; margin-bottom: var(--space-3);
}
.reaction-type-badge {
  padding: 4px 14px; border-radius: var(--radius-full); font-size: .75rem;
  font-weight: 700; text-transform: uppercase; letter-spacing: 1px;
}
.badge-exothermic { background: rgba(239,68,68,.2); color: #ef4444; }
.badge-endothermic { background: rgba(59,130,246,.2); color: #3b82f6; }
.badge-neutral { background: rgba(168,85,247,.2); color: #a855f7; }

.result-equation {
  font-family: 'Courier New', monospace; font-size: 1.2rem; text-align: center;
  padding: var(--space-4); background: var(--color-surface-alt);
  border-radius: var(--radius-md); margin-bottom: var(--space-4);
  border: 1px solid var(--color-border); font-weight: 700;
  color: var(--color-primary);
}

.result-details {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-3);
}
@media (max-width: 640px) {
  .result-details { grid-template-columns: 1fr; }
}
.detail-card {
  padding: var(--space-3); background: var(--color-surface-alt);
  border-radius: var(--radius-md); border: 1px solid var(--color-border);
}
.detail-card h4 { font-size: .85rem; margin-bottom: var(--space-2); }
.detail-card p { font-size: .8rem; color: var(--color-text-secondary); margin: 0; }

.safety-info {
  margin-top: var(--space-3); padding: var(--space-3);
  background: rgba(239,68,68,.1); border-radius: var(--radius-md);
  border: 1px solid rgba(239,68,68,.3); font-size: .8rem;
}

/* Info Panel */
.info-panel { max-height: 80vh; overflow-y: auto; }
.tabs { display: flex; gap: 4px; margin-bottom: var(--space-3); }
.tab-btn {
  flex: 1; padding: 6px 8px; font-size: .75rem; border-radius: var(--radius-md);
  background: var(--color-surface-alt); border: 1px solid var(--color-border);
  color: var(--color-text); cursor: pointer; transition: all .2s;
}
.tab-btn.active { background: var(--color-primary); color: #fff; border-color: var(--color-primary); }
.tab-content.hidden { display: none; }

.history-item {
  padding: var(--space-2); border-bottom: 1px solid var(--color-border);
  font-size: .8rem; cursor: pointer; transition: background .2s;
}
.history-item:hover { background: var(--color-surface-alt); }
.history-eq { font-family: monospace; font-weight: 600; color: var(--color-primary); }
.history-time { font-size: .65rem; color: var(--color-text-secondary); }

/* Element Info Card */
.info-card { text-align: center; }
.info-symbol { font-size: 3rem; font-weight: 900; color: var(--color-primary); }
.info-name { font-size: 1.2rem; font-weight: 700; margin: var(--space-2) 0; }
.info-props { text-align: left; }
.info-prop {
  display: flex; justify-content: space-between; padding: 4px 0;
  border-bottom: 1px solid var(--color-border); font-size: .8rem;
}

/* Quiz */
.quiz-options { display: flex; flex-direction: column; gap: 6px; }
.quiz-opt {
  padding: 10px; border: 1px solid var(--color-border); border-radius: var(--radius-md);
  background: var(--color-surface-alt); cursor: pointer; transition: all .2s;
  text-align: left; font-size: .85rem; color: var(--color-text);
}
.quiz-opt:hover { border-color: var(--color-primary); }
.quiz-opt.correct { border-color: #22c55e; background: rgba(34,197,94,.15); }
.quiz-opt.wrong { border-color: #ef4444; background: rgba(239,68,68,.15); }

/* Stats Bar */
.stats-bar {
  display: flex; justify-content: space-around; text-align: center;
}
.stat-item { display: flex; flex-direction: column; }
.stat-num { font-size: 1.6rem; font-weight: 900; background: linear-gradient(135deg, var(--color-primary), var(--color-accent)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.stat-lbl { font-size: .7rem; color: var(--color-text-secondary); text-transform: uppercase; letter-spacing: 1px; }

/* Reaction Animation */
.reaction-flash {
  animation: flashReaction .6s ease;
}
@keyframes flashReaction {
  0% { box-shadow: 0 0 0 rgba(255,255,255,0); }
  50% { box-shadow: 0 0 40px rgba(255,200,50,.6), inset 0 0 30px rgba(255,200,50,.3); }
  100% { box-shadow: 0 0 0 rgba(255,255,255,0); }
}

.hidden { display: none !important; }