:root {
  --bg: #fff8e7;
  --ink: #1a1a2e;
  --paper: #fffdf5;
  --accent: #ff5b6e;
  --accent2: #ffd23f;
  --accent3: #6cb4ff;
  --accent4: #b4d44e;
  --shadow: 0 4px 0 rgba(26,26,46,0.85);
  --shadow-sm: 0 2px 0 rgba(26,26,46,0.85);
  --shadow-lg: 6px 6px 0 rgba(26,26,46,0.85);

  --c-alkali: #ff6b9d;
  --c-alkaline: #ffa45e;
  --c-transition: #ffd23f;
  --c-postt: #b4d44e;
  --c-metalloid: #5fc9c3;
  --c-nonmetal: #6cb4ff;
  --c-halogen: #c285ff;
  --c-noble: #ff8fb3;
  --c-lanth: #ffb88c;
  --c-actin: #f78ca0;
  --c-unknown: #d4d4d4;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  background: var(--bg);
  color: var(--ink);
  font-family: 'Fredoka', sans-serif;
  overflow-x: hidden;
  min-height: 100vh;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: radial-gradient(circle, rgba(26,26,46,0.06) 1.5px, transparent 1.5px);
  background-size: 24px 24px;
  pointer-events: none;
  z-index: 0;
}

.wrap {
  position: relative;
  z-index: 1;
  max-width: 1400px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

/* Header */
header {
  text-align: center;
  margin-bottom: 24px;
}
header h1 {
  font-size: clamp(1.8rem, 5vw, 3.4rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  display: inline-block;
  transform: rotate(-2deg);
  background: var(--accent);
  color: white;
  padding: 12px 24px 16px;
  border-radius: 18px;
  border: 3px solid var(--ink);
  box-shadow: var(--shadow);
}
header h1 .emoji { display: inline-block; transform: rotate(8deg); }
header p {
  margin-top: 18px;
  font-size: 1.05rem;
  opacity: 0.75;
  font-weight: 500;
}

/* Mode tabs */
.mode-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin: 20px 0 24px;
  flex-wrap: wrap;
}
.mode-tab {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 10px 18px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 6px;
}
.mode-tab:hover { transform: translate(-1px, -1px); }
.mode-tab.active {
  background: var(--ink);
  color: var(--accent2);
}

/* Mode panels */
.panel { display: none; }
.panel.active { display: block; animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* Search */
.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}
.search-box {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow-sm);
  min-width: 240px;
}
.search-box input {
  border: none; outline: none;
  font-family: inherit; font-size: 1rem; font-weight: 500;
  color: var(--ink); background: transparent; width: 100%;
}
.search-box input::placeholder { color: rgba(26,26,46,0.4); }

/* Color-by bar */
.color-by-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.color-by-label {
  font-weight: 700;
  font-size: 0.9rem;
  white-space: nowrap;
}
.color-by-pills {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
}
.color-pill {
  background: white;
  border: 2.5px solid var(--ink);
  border-radius: 999px;
  padding: 5px 13px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.8rem;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease;
  color: var(--ink);
}
.color-pill:hover { transform: translate(-1px, -1px); }
.color-pill.active { background: var(--ink); color: var(--accent2); }

/* Color-by gradient legend */
.legend-gradient {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0;
}
.legend-gradient-bar {
  flex: 1;
  height: 16px;
  border-radius: 999px;
  border: 2px solid var(--ink);
}
.legend-gradient-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  font-weight: 600;
  opacity: 0.7;
  margin-top: 2px;
}

.filter-pills {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 22px;
}
.pill {
  background: white;
  border: 2.5px solid var(--ink);
  border-radius: 999px;
  padding: 6px 14px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.82rem;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease;
  color: var(--ink);
}
.pill:hover { transform: translate(-1px, -1px); }
.pill.active { background: var(--ink); color: var(--accent2); }

/* Table */
.table-scroll {
  overflow-x: auto;
  padding: 4px 20px;
  margin: 0 -20px;
}
.table-scroll::-webkit-scrollbar { height: 12px; }
.table-scroll::-webkit-scrollbar-track { background: rgba(26,26,46,0.08); border-radius: 8px; }
.table-scroll::-webkit-scrollbar-thumb { background: var(--ink); border-radius: 8px; }

.table {
  display: grid;
  grid-template-columns: repeat(18, minmax(58px, 1fr));
  grid-auto-rows: minmax(58px, 1fr);
  gap: 5px;
  min-width: 1100px;
}

.cell {
  border: 2.5px solid var(--ink);
  border-radius: 8px;
  padding: 4px 5px;
  cursor: pointer;
  position: relative;
  transition: transform 0.15s ease, box-shadow 0.15s ease, opacity 0.3s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  user-select: none;
}
.cell:hover {
  transform: translate(-2px, -2px) rotate(-1deg);
  box-shadow: 4px 4px 0 rgba(26,26,46,0.85);
  z-index: 5;
}
.cell.dimmed { opacity: 0.18; pointer-events: none; }
.cell.hidden { opacity: 0.05; pointer-events: none; filter: grayscale(1); }
.cell.compare-selected {
  box-shadow: 0 0 0 4px var(--accent), var(--shadow-sm);
  transform: scale(1.05);
}
.cell.quiz-target {
  animation: wiggle 0.6s ease infinite;
}
@keyframes wiggle {
  0%, 100% { transform: rotate(0deg); }
  25% { transform: rotate(-3deg); }
  75% { transform: rotate(3deg); }
}

.cell .num { font-family: 'Space Mono', monospace; font-size: 0.62rem; font-weight: 700; opacity: 0.8; line-height: 1; }
.cell .sym { font-size: 1.4rem; font-weight: 700; text-align: center; line-height: 1; letter-spacing: -0.02em; }
.cell .name { font-size: 0.65rem; text-align: center; line-height: 1; font-weight: 600; text-transform: uppercase; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: rgba(26,26,46,0.85); }
.cell .mass { font-family: 'Space Mono', monospace; font-size: 0.6rem; text-align: center; opacity: 0.85; line-height: 1; color: rgba(26,26,46,0.75); }

.cat-alkali { background: var(--c-alkali); }
.cat-alkaline { background: var(--c-alkaline); }
.cat-transition { background: var(--c-transition); }
.cat-post-transition { background: var(--c-postt); }
.cat-metalloid { background: var(--c-metalloid); }
.cat-nonmetal { background: var(--c-nonmetal); }
.cat-halogen { background: var(--c-halogen); }
.cat-noble { background: var(--c-noble); }
.cat-lanthanide { background: var(--c-lanth); }
.cat-actinide { background: var(--c-actin); }

.placeholder {
  border: 2px dashed rgba(26,26,46,0.15);
  border-radius: 8px;
  background: transparent;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.65rem; color: rgba(26,26,46,0.4); font-weight: 600; font-style: italic;
}

/* Modal */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(26,26,46,0.55);
  backdrop-filter: blur(4px);
  display: none; align-items: center; justify-content: center;
  padding: 20px; z-index: 100;
  animation: fadeIn 0.2s ease;
}
.modal-overlay.open { display: flex; }

.modal {
  background: var(--paper);
  border: 4px solid var(--ink);
  border-radius: 22px;
  box-shadow: var(--shadow-lg);
  max-width: 600px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
  animation: slideUp 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}
@keyframes slideUp {
  from { transform: translateY(40px) scale(0.9); opacity: 0; }
  to { transform: translateY(0) scale(1); opacity: 1; }
}

.modal-header {
  padding: 24px 24px 16px;
  border-bottom: 3px dashed rgba(26,26,46,0.2);
  display: flex; align-items: center; gap: 18px;
}
.modal-symbol {
  width: 90px; height: 90px;
  border: 3px solid var(--ink);
  border-radius: 14px;
  display: flex; flex-direction: column; justify-content: center; align-items: center;
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
}
.modal-symbol .num { font-family: 'Space Mono', monospace; font-size: 0.75rem; font-weight: 700; align-self: flex-start; margin-left: 8px; margin-top: 4px; }
.modal-symbol .sym { font-size: 2.6rem; font-weight: 700; line-height: 1; margin-top: -4px; }
.modal-info { flex: 1; }
.modal-info h2 { font-size: 2rem; font-weight: 700; line-height: 1; letter-spacing: -0.01em; }
.modal-info .category {
  margin-top: 8px;
  display: inline-block;
  background: var(--ink); color: var(--accent2);
  padding: 4px 12px; border-radius: 999px;
  font-size: 0.78rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.05em;
}

.close-btn {
  position: absolute; top: 14px; right: 14px;
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 2.5px solid var(--ink);
  background: var(--accent); color: white;
  font-size: 1.1rem; font-weight: 700;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  display: flex; align-items: center; justify-content: center;
  font-family: inherit;
}
.close-btn:hover { transform: rotate(90deg); transition: transform 0.2s ease; }

.modal-body { padding: 20px 24px 24px; }

/* Atom animation */
.atom-container {
  display: flex;
  justify-content: center;
  margin-bottom: 18px;
  background: linear-gradient(135deg, #1a1a2e 0%, #2d2d4e 100%);
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 16px;
  box-shadow: var(--shadow-sm);
}
.atom-svg { width: 100%; max-width: 280px; height: 200px; }
.nucleus { fill: var(--accent); }
.nucleus-text { fill: white; font-family: 'Fredoka', sans-serif; font-weight: 700; font-size: 14px; text-anchor: middle; dominant-baseline: central; }
.orbit { fill: none; stroke: rgba(255,255,255,0.2); stroke-width: 1; stroke-dasharray: 2 3; }
.electron { fill: var(--accent2); stroke: var(--ink); stroke-width: 1; }

.fun-fact {
  background: var(--accent2);
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 14px 16px;
  margin-bottom: 14px;
  box-shadow: var(--shadow-sm);
}
.fact-label {
  display: inline-block;
  background: var(--ink); color: var(--accent2);
  padding: 3px 10px; border-radius: 999px;
  font-size: 0.7rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.05em;
  margin-bottom: 6px;
}
.fun-fact p, .what-if p, .where p { font-size: 0.97rem; line-height: 1.45; font-weight: 500; }

.what-if {
  background: #ff8fb3;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 14px 16px;
  margin-bottom: 14px;
  box-shadow: var(--shadow-sm);
}
.where {
  background: var(--accent3);
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 14px 16px;
  margin-bottom: 14px;
  box-shadow: var(--shadow-sm);
  color: var(--ink);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-bottom: 14px;
}
.stat {
  background: white;
  border: 2.5px solid var(--ink);
  border-radius: 12px;
  padding: 10px 12px;
  box-shadow: var(--shadow-sm);
}
.stat .label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.05em; opacity: 0.7; font-weight: 600; margin-bottom: 2px; }
.stat .value { font-family: 'Space Mono', monospace; font-size: 1.05rem; font-weight: 700; }
.stat-full { grid-column: 1 / -1; }

.uses {
  background: white;
  border: 2.5px solid var(--ink);
  border-radius: 12px;
  padding: 14px 16px;
  box-shadow: var(--shadow-sm);
}
.uses h3 { font-size: 0.95rem; font-weight: 700; margin-bottom: 8px; }
.uses ul { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
.uses li {
  background: var(--bg); border: 2px solid var(--ink);
  padding: 4px 10px; border-radius: 999px;
  font-size: 0.82rem; font-weight: 500;
}

/* Legend */
.legend {
  margin-top: 28px;
  padding: 18px;
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  box-shadow: var(--shadow-sm);
}
.legend h3 { font-size: 0.95rem; font-weight: 700; margin-bottom: 12px; text-transform: uppercase; letter-spacing: 0.05em; }
.legend-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 8px; }
.legend-item { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; font-weight: 500; }
.legend-swatch { width: 22px; height: 22px; border: 2px solid var(--ink); border-radius: 6px; flex-shrink: 0; }

/* Compare mode */
.compare-banner {
  background: var(--accent3);
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 14px 18px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.compare-banner p { font-weight: 600; font-size: 0.95rem; }
.compare-slots {
  display: flex;
  gap: 8px;
  align-items: center;
}
.compare-slot {
  width: 50px; height: 50px;
  background: white;
  border: 2.5px solid var(--ink);
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 1.2rem;
  color: rgba(26,26,46,0.3);
  box-shadow: var(--shadow-sm);
}
.compare-slot.filled { color: var(--ink); }
.btn {
  background: var(--accent);
  color: white;
  border: 3px solid var(--ink);
  border-radius: 12px;
  padding: 8px 16px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease;
}
.btn:hover { transform: translate(-1px, -1px); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.btn.secondary { background: white; color: var(--ink); }
.btn.green { background: var(--accent4); color: var(--ink); }

.compare-result {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 20px;
}
.compare-card {
  background: var(--paper);
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 18px;
  box-shadow: var(--shadow-sm);
}
.compare-card .big-sym {
  font-size: 3rem; font-weight: 700; line-height: 1; text-align: center;
  padding: 16px; border-radius: 12px; border: 3px solid var(--ink);
  box-shadow: var(--shadow-sm); margin-bottom: 12px;
}
.compare-card h3 { font-size: 1.3rem; font-weight: 700; text-align: center; margin-bottom: 10px; }
.compare-card .row {
  display: flex; justify-content: space-between;
  padding: 6px 0; border-bottom: 2px dashed rgba(26,26,46,0.15);
  font-size: 0.88rem;
}
.compare-card .row:last-child { border-bottom: none; }
.compare-card .row .k { font-weight: 600; opacity: 0.7; }
.compare-card .row .v { font-weight: 700; font-family: 'Space Mono', monospace; }

/* History timeline */
.timeline-container {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}
.timeline-year {
  font-family: 'Space Mono', monospace;
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  color: var(--accent);
  margin-bottom: 8px;
  line-height: 1;
}
.timeline-info {
  text-align: center;
  font-weight: 500;
  margin-bottom: 16px;
  font-size: 0.95rem;
  min-height: 2.8em;
}
.timeline-info strong { color: var(--ink); font-weight: 700; }
.timeline-slider {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 12px;
  background: var(--bg);
  border: 2.5px solid var(--ink);
  border-radius: 999px;
  outline: none;
  box-shadow: var(--shadow-sm);
}
.timeline-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 28px; height: 28px;
  background: var(--accent);
  border: 3px solid var(--ink);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
}
.timeline-slider::-moz-range-thumb {
  width: 28px; height: 28px;
  background: var(--accent);
  border: 3px solid var(--ink);
  border-radius: 50%;
  cursor: pointer;
}
.timeline-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 8px;
  font-family: 'Space Mono', monospace;
  font-size: 0.75rem;
  opacity: 0.6;
  font-weight: 700;
}

/* Quiz */
.quiz-container {
  max-width: 700px;
  margin: 0 auto;
}
.quiz-header {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 16px 20px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.quiz-stat { display: flex; flex-direction: column; align-items: center; }
.quiz-stat .label { font-size: 0.7rem; text-transform: uppercase; opacity: 0.7; font-weight: 600; }
.quiz-stat .value { font-family: 'Space Mono', monospace; font-size: 1.6rem; font-weight: 700; line-height: 1; }
.quiz-stat .value.streak { color: var(--accent); }
.quiz-stat .value.score { color: var(--accent4); filter: brightness(0.7); }

.quiz-card {
  background: var(--paper);
  border: 4px solid var(--ink);
  border-radius: 20px;
  padding: 28px 24px;
  box-shadow: var(--shadow-lg);
  text-align: center;
}
.quiz-question {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 24px;
  line-height: 1.3;
}
.quiz-question strong { color: var(--accent); font-weight: 700; }
.quiz-options {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}
.quiz-option {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 16px 12px;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease, background 0.2s ease;
  font-family: inherit;
  font-weight: 600;
  font-size: 1rem;
  color: var(--ink);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}
.quiz-option:hover:not(:disabled) { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 rgba(26,26,46,0.85); }
.quiz-option .opt-sym { font-size: 1.6rem; font-weight: 700; }
.quiz-option .opt-name { font-size: 0.85rem; opacity: 0.8; }
.quiz-option.correct { background: var(--accent4); animation: pop 0.4s ease; }
.quiz-option.wrong { background: #ff8fb3; animation: shake 0.4s ease; }
@keyframes pop { 0% { transform: scale(1); } 50% { transform: scale(1.1); } 100% { transform: scale(1); } }
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}
.quiz-option:disabled { cursor: default; }

.quiz-feedback {
  margin-top: 18px;
  padding: 14px;
  border-radius: 12px;
  border: 3px solid var(--ink);
  background: var(--bg);
  box-shadow: var(--shadow-sm);
  font-weight: 500;
  display: none;
}
.quiz-feedback.show { display: block; animation: fadeIn 0.3s ease; }
.quiz-feedback.correct { background: var(--accent4); }
.quiz-feedback.wrong { background: #ffd0db; }

.quiz-actions { margin-top: 16px; display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }

footer { text-align: center; margin-top: 30px; font-size: 0.85rem; opacity: 0.6; font-weight: 500; }
.footer-dedication { font-size: 0.95rem; font-style: italic; margin-bottom: 4px; }
footer a { color: inherit; text-decoration: none; }
footer a:hover { text-decoration: underline; }

/* Molecule mode */
.molecule-lab {
  max-width: 800px;
  margin: 0 auto;
}

.mol-result {
  background: var(--accent4);
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px 24px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
  text-align: center;
  display: none;
  animation: slideUp 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.mol-result.show { display: block; }
.mol-result .mol-emoji { font-size: 3rem; display: block; margin-bottom: 6px; }
.mol-result .mol-name { font-size: 1.5rem; font-weight: 700; }
.mol-result .mol-formula-display {
  font-family: 'Space Mono', monospace;
  font-size: 1rem;
  font-weight: 700;
  opacity: 0.7;
  margin-top: 2px;
}
.mol-result .mol-fact {
  font-size: 0.95rem;
  font-weight: 500;
  margin-top: 10px;
  line-height: 1.4;
}

.mol-bench-area {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
}
.mol-bench-area h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.mol-bench {
  min-height: 180px;
  border: 3px dashed rgba(26,26,46,0.2);
  border-radius: 14px;
  padding: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  align-content: center;
  justify-content: center;
  transition: border-color 0.3s, background 0.3s, box-shadow 0.3s;
  background-image: radial-gradient(circle, rgba(26,26,46,0.03) 1px, transparent 1px);
  background-size: 16px 16px;
}
.mol-bench.drag-active {
  border-color: var(--accent3);
  animation: benchPulse 1.2s ease infinite;
}
@keyframes benchPulse {
  0%, 100% { box-shadow: inset 0 0 0 0 rgba(108,180,255,0); }
  50% { box-shadow: inset 0 0 12px 2px rgba(108,180,255,0.15); }
}
.mol-bench.drag-over {
  border-color: var(--accent);
  background-color: rgba(255,91,110,0.06);
  animation: none;
  box-shadow: inset 0 0 16px 2px rgba(255,91,110,0.12);
}
.pal-el.dragging {
  opacity: 0.4;
  transform: scale(0.95);
  box-shadow: none;
}
.mol-bench.empty::after {
  content: 'Drag elements here to build a molecule!';
  color: rgba(26,26,46,0.3);
  font-weight: 500;
  font-size: 0.95rem;
}

.bench-atom {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  border: 3px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.3rem;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease;
  animation: dropIn 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  user-select: none;
}
@keyframes dropIn {
  from { transform: scale(0) rotate(-180deg); }
  to { transform: scale(1) rotate(0); }
}
.bench-atom:hover { transform: scale(1.12); }
.bench-atom::after {
  content: '\2715';
  position: absolute;
  top: -6px;
  right: -6px;
  width: 18px;
  height: 18px;
  background: var(--accent);
  color: white;
  border-radius: 50%;
  font-size: 0.55rem;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.15s;
  border: 2px solid var(--ink);
  font-weight: 700;
}
.bench-atom:hover::after { opacity: 1; }
.bench-atom.matched {
  animation: pop 0.5s ease;
  box-shadow: 0 0 0 4px var(--accent4), var(--shadow-sm);
}

.mol-formula {
  text-align: center;
  font-family: 'Space Mono', monospace;
  font-size: 1.2rem;
  font-weight: 700;
  margin-top: 12px;
  min-height: 1.5em;
  color: var(--ink);
}

.mol-actions {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 12px;
}

.mol-palette-area {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
}
.mol-palette-area h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
}
.mol-palette {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(68px, 1fr));
  gap: 8px;
}

.pal-el {
  border: 2.5px solid var(--ink);
  border-radius: 10px;
  padding: 8px 4px;
  text-align: center;
  cursor: grab;
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease;
  user-select: none;
  touch-action: none;
}
.pal-el:hover {
  transform: translate(-2px, -2px);
  box-shadow: 4px 4px 0 rgba(26,26,46,0.85);
}
.pal-el:active { cursor: grabbing; }
.pal-el .pal-sym { font-size: 1.4rem; font-weight: 700; line-height: 1; }
.pal-el .pal-name {
  font-size: 0.6rem;
  font-weight: 500;
  text-transform: uppercase;
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.drag-ghost {
  position: fixed;
  width: 54px;
  height: 54px;
  border-radius: 50%;
  border: 3px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.3rem;
  font-family: 'Fredoka', sans-serif;
  pointer-events: none;
  z-index: 1000;
  opacity: 0.9;
  box-shadow: var(--shadow-lg);
  transform: translate(-50%, -50%) scale(1.1);
}

.mol-recipes-area {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  box-shadow: var(--shadow-sm);
}
.mol-recipes-area h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.mol-progress {
  background: var(--ink);
  color: var(--accent2);
  padding: 2px 10px;
  border-radius: 999px;
  font-size: 0.75rem;
}
.mol-recipes {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
  max-height: 320px;
  overflow-y: auto;
  padding-right: 4px;
}
.mol-recipes::-webkit-scrollbar { width: 8px; }
.mol-recipes::-webkit-scrollbar-track { background: rgba(26,26,46,0.06); border-radius: 8px; }
.mol-recipes::-webkit-scrollbar-thumb { background: var(--ink); border-radius: 8px; }
.recipe-item {
  border: 2.5px solid var(--ink);
  border-radius: 10px;
  padding: 10px 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg);
  opacity: 0.55;
  transition: opacity 0.3s, background 0.3s;
  box-shadow: var(--shadow-sm);
}
.recipe-item.discovered {
  opacity: 1;
  background: var(--accent2);
}
.recipe-item .recipe-emoji { font-size: 1.3rem; flex-shrink: 0; }
.recipe-item .recipe-info { flex: 1; min-width: 0; }
.recipe-item .recipe-formula {
  font-family: 'Space Mono', monospace;
  font-size: 0.8rem;
  font-weight: 700;
}
.recipe-item .recipe-name { font-size: 0.78rem; font-weight: 500; }

/* Race mode */
.race-hud {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 16px 20px;
  margin-bottom: 18px;
  box-shadow: var(--shadow-sm);
  display: flex;
  justify-content: space-around;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.race-stat { display: flex; flex-direction: column; align-items: center; }
.race-stat .label { font-size: 0.7rem; text-transform: uppercase; opacity: 0.7; font-weight: 600; }
.race-stat .value { font-family: 'Space Mono', monospace; font-size: 1.6rem; font-weight: 700; line-height: 1; }

.race-prompt {
  text-align: center;
  margin-bottom: 18px;
  min-height: 80px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.race-target {
  font-size: 2rem;
  font-weight: 700;
  animation: fadeIn 0.25s ease;
}
.race-target .race-label {
  font-size: 0.9rem;
  font-weight: 600;
  opacity: 0.6;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  display: block;
  margin-bottom: 4px;
}
.race-start-btn {
  font-size: 1.2rem;
  padding: 14px 32px;
}
.race-result {
  animation: slideUp 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  text-align: center;
}
.race-result .race-emoji { font-size: 3rem; display: block; margin-bottom: 4px; }
.race-result .race-time { font-family: 'Space Mono', monospace; font-size: 1.8rem; font-weight: 700; color: var(--accent); }
.race-result .race-avg { font-size: 1rem; font-weight: 600; margin-top: 4px; opacity: 0.7; }
.race-result .race-new-best { color: var(--accent4); filter: brightness(0.7); font-weight: 700; opacity: 1; }

/* Difficulty picker */
.race-diff-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  max-width: 420px;
  margin: 0 auto;
}
.race-diff-card {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 16px;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  font-family: inherit;
  color: var(--ink);
}
.race-diff-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow);
}
.race-diff-emoji { font-size: 2rem; }
.race-diff-name { font-size: 1.1rem; font-weight: 700; }
.race-diff-desc { font-size: 0.78rem; opacity: 0.65; font-weight: 500; text-align: center; }

/* Custom config */
.race-custom-config {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  margin-top: 14px;
  box-shadow: var(--shadow-sm);
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
  animation: fadeIn 0.3s ease;
}
.race-custom-config h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 12px;
  text-align: center;
}
.race-custom-cats {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
  margin-bottom: 14px;
}
.race-cat-check {
  cursor: pointer;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 5px 12px;
  border-radius: 999px;
  border: 2.5px solid var(--ink);
  box-shadow: var(--shadow-sm);
  transition: opacity 0.2s, transform 0.12s;
  user-select: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.race-cat-check:hover { transform: translate(-1px, -1px); }
.race-cat-check input { display: none; }
.race-cat-check.unchecked {
  opacity: 0.3;
  box-shadow: none;
}
.race-custom-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 10px 0;
  font-size: 0.88rem;
  font-weight: 500;
  justify-content: center;
  flex-wrap: wrap;
}
.race-custom-row label {
  display: flex;
  align-items: center;
  gap: 6px;
}
.race-custom-row input[type="range"] { width: 120px; }
.race-custom-row input[type="checkbox"] { width: 18px; height: 18px; cursor: pointer; accent-color: var(--accent); }

.cell.race-correct {
  animation: pop 0.4s ease;
  box-shadow: 0 0 0 4px var(--accent4), var(--shadow-sm);
}
.cell.race-wrong {
  animation: shake 0.4s ease;
}

/* Hint animations */
.cell.race-hint-cat {
  box-shadow: 0 0 0 3px var(--accent3), 0 0 12px rgba(108,180,255,0.4);
  animation: hintPulse 1s ease infinite;
}
.cell.race-hint-row {
  box-shadow: 0 0 0 4px var(--accent2), 0 0 16px rgba(255,210,63,0.5);
  animation: hintPulse 0.7s ease infinite;
}
@keyframes hintPulse {
  0%, 100% { filter: brightness(1); }
  50% { filter: brightness(1.18); }
}

/* Inside You (Body) */
.body-container {
  max-width: 1000px;
  margin: 0 auto;
}
.body-overview {
  text-align: center;
  margin-bottom: 24px;
}
.body-overview h2 {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 6px;
}
.body-subtitle {
  font-size: 1rem;
  font-weight: 500;
  opacity: 0.7;
  margin-bottom: 18px;
}
.body-comp-bar {
  display: flex;
  height: 32px;
  border-radius: 999px;
  border: 3px solid var(--ink);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  margin: 0 auto 10px;
  max-width: 700px;
}
.body-comp-seg {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
  overflow: hidden;
  transition: opacity 0.2s;
  cursor: pointer;
  position: relative;
}
.body-comp-seg:hover { opacity: 0.8; }
.body-comp-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  justify-content: center;
  font-size: 0.78rem;
  font-weight: 500;
  max-width: 700px;
  margin: 0 auto;
}
.body-comp-legend-item {
  display: flex;
  align-items: center;
  gap: 5px;
}
.body-comp-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  border: 2px solid var(--ink);
  flex-shrink: 0;
}

/* Body systems card grid */
.body-systems-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 24px;
}
.body-system-card {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 18px 16px;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 6px;
  user-select: none;
  position: relative;
  overflow: hidden;
}
.body-system-card::before {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0.12;
  border-radius: 13px;
  transition: opacity 0.2s;
}
.body-system-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 4px 4px 0 rgba(26,26,46,0.85);
}
.body-system-card:hover::before { opacity: 0.2; }
.body-system-card.active {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent), var(--shadow-sm);
  transform: scale(1.03);
}
.body-system-card.active::before { opacity: 0.25; }
.body-system-emoji {
  font-size: 2.6rem;
  line-height: 1;
  filter: drop-shadow(1px 1px 0 rgba(26,26,46,0.15));
}
.body-system-name {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.1;
}
.body-system-hint {
  font-size: 0.72rem;
  font-weight: 500;
  opacity: 0.55;
  line-height: 1.3;
}
.body-system-elements {
  display: flex;
  gap: 4px;
  margin-top: 4px;
  flex-wrap: wrap;
  justify-content: center;
}
.body-system-el-pip {
  width: 24px;
  height: 24px;
  border-radius: 6px;
  border: 2px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.6rem;
  line-height: 1;
}

/* Body detail panel */
.body-detail {
  margin-bottom: 28px;
}
.body-detail-card {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 18px;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  animation: slideUp 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.body-detail-header {
  padding: 20px 24px;
  border-bottom: 3px dashed rgba(26,26,46,0.15);
  display: flex;
  align-items: center;
  gap: 14px;
}
.body-detail-header .body-detail-emoji { font-size: 2.4rem; }
.body-detail-header-text h3 { font-size: 1.5rem; font-weight: 700; }
.body-detail-header-text p { font-size: 0.92rem; font-weight: 500; opacity: 0.7; margin-top: 3px; line-height: 1.4; }
.body-detail-elements {
  padding: 20px 24px;
}
.body-detail-elements h4 {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  opacity: 0.6;
  margin-bottom: 12px;
}
.body-el-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.body-el-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border-radius: 12px;
  border: 2.5px solid var(--ink);
  box-shadow: var(--shadow-sm);
  transition: transform 0.12s;
}
.body-el-row:hover { transform: translate(-1px, -1px); }
.body-el-sym {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  border: 2.5px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.2rem;
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
}
.body-el-info { flex: 1; min-width: 0; }
.body-el-name { font-weight: 700; font-size: 0.95rem; }
.body-el-role { font-size: 0.82rem; font-weight: 500; opacity: 0.7; line-height: 1.3; margin-top: 2px; }
.body-el-bar-wrap {
  width: 60px;
  height: 10px;
  background: var(--bg);
  border: 2px solid var(--ink);
  border-radius: 999px;
  overflow: hidden;
  flex-shrink: 0;
}
.body-el-bar {
  height: 100%;
  border-radius: 999px;
  transition: width 0.5s ease;
}

/* Fun facts */
.body-fun-facts {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 16px;
  padding: 20px;
  box-shadow: var(--shadow-sm);
}
.body-fun-facts h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 14px;
  text-align: center;
}
.body-facts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 10px;
}
.body-fact-card {
  background: var(--bg);
  border: 2.5px solid var(--ink);
  border-radius: 12px;
  padding: 14px 16px;
  box-shadow: var(--shadow-sm);
}
.body-fact-card .body-fact-emoji { font-size: 1.3rem; display: block; margin-bottom: 4px; }
.body-fact-card p { font-size: 0.85rem; font-weight: 500; line-height: 1.4; }

@media (max-width: 600px) {
  .body-systems-grid { grid-template-columns: repeat(2, 1fr); }
}

/* Glossary */
.glossary-container {
  max-width: 900px;
  margin: 0 auto;
}
.glossary-search-box {
  background: white;
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 20px;
  max-width: 360px;
  margin-left: auto;
  margin-right: auto;
}
.glossary-search-box input {
  border: none; outline: none;
  font-family: inherit; font-size: 1rem; font-weight: 500;
  color: var(--ink); background: transparent; width: 100%;
}
.glossary-search-box input::placeholder { color: rgba(26,26,46,0.4); }
.glossary-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
}
.glossary-card {
  background: var(--paper);
  border: 3px solid var(--ink);
  border-radius: 14px;
  padding: 16px 18px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.glossary-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow);
}
.glossary-card .glossary-term {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.glossary-card .glossary-term .glossary-emoji { font-size: 1.2rem; }
.glossary-card .glossary-def {
  font-size: 0.9rem;
  font-weight: 500;
  line-height: 1.45;
  color: rgba(26,26,46,0.8);
}
.glossary-card .glossary-example {
  margin-top: 8px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent);
  font-style: italic;
}
.glossary-card.hidden { display: none; }

@media (max-width: 600px) {
  .modal-header { flex-direction: column; text-align: center; }
  .stats-grid, .compare-result, .quiz-options { grid-template-columns: 1fr; }
  .mol-palette { grid-template-columns: repeat(auto-fill, minmax(56px, 1fr)); }
  .mol-recipes { grid-template-columns: 1fr; }
  .race-diff-grid { grid-template-columns: 1fr; max-width: 260px; }
}