/* ===========================================================================
   Chemistry Lab — styles
   Dark "lab bench" theme with a category colour system.
   =========================================================================== */
:root {
  --bg: #0b0f1a;
  --bg-2: #111726;
  --panel: rgba(23, 31, 48, 0.72);
  --panel-solid: #171f30;
  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.18);
  --text: #e8edf7;
  --text-dim: #9aa6bd;
  --text-faint: #66728c;
  --accent: #5eead4;
  --accent-2: #818cf8;
  --danger: #fb7185;
  --warn: #fbbf24;
  --ok: #4ade80;
  --radius: 14px;
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.45);

  /* Category palette */
  --c-alkali: #f87171;
  --c-alkaline: #fb923c;
  --c-transition: #fbbf24;
  --c-posttransition: #4ade80;
  --c-metalloid: #2dd4bf;
  --c-diatomic: #38bdf8;
  --c-polyatomic: #818cf8;
  --c-noble: #c084fc;
  --c-lanthanide: #f472b6;
  --c-actinide: #fb7185;
  --c-unknown: #94a3b8;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background:
    radial-gradient(1200px 800px at 80% -10%, rgba(129, 140, 248, 0.10), transparent 60%),
    radial-gradient(1000px 700px at -10% 110%, rgba(94, 234, 212, 0.08), transparent 55%),
    var(--bg);
  color: var(--text);
  font: 15px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { margin: 0; font-weight: 700; }

#app { max-width: 1500px; margin: 0 auto; padding: 14px 16px 0; }

/* ---------- Top bar ---------- */
#topbar {
  display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  padding: 10px 14px; margin-bottom: 14px;
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); backdrop-filter: blur(8px);
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark { font-size: 30px; filter: drop-shadow(0 2px 8px rgba(94,234,212,.5)); }
.brand-text h1 { font-size: 19px; letter-spacing: .2px; }
.brand-text p { margin: 1px 0 0; font-size: 12px; color: var(--text-dim); }
.toolbar { display: flex; align-items: center; gap: 10px; margin-left: auto; flex-wrap: wrap; }
.search-wrap input {
  width: 240px; max-width: 46vw; padding: 8px 12px; color: var(--text);
  background: rgba(0,0,0,.25); border: 1px solid var(--line-strong);
  border-radius: 10px; outline: none; font-size: 13px;
}
.search-wrap input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(94,234,212,.15); }
.select-wrap { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--text-dim); }
.select-wrap select {
  background: rgba(0,0,0,.25); color: var(--text); border: 1px solid var(--line-strong);
  border-radius: 10px; padding: 7px 8px; font-size: 13px; outline: none;
}
.icon-btn {
  width: 36px; height: 36px; display: grid; place-items: center;
  background: rgba(0,0,0,.25); color: var(--text); border: 1px solid var(--line-strong);
  border-radius: 10px; cursor: pointer; font-size: 15px;
}
.icon-btn:hover { border-color: var(--accent); }
.icon-btn[aria-pressed="false"] { opacity: .5; }

/* ---------- Layout ---------- */
#layout { display: grid; grid-template-columns: minmax(0, 1fr) 372px; gap: 16px; align-items: start; }
@media (max-width: 1080px) { #layout { grid-template-columns: 1fr; } }

/* ---------- Periodic table ---------- */
#table-section {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 14px; overflow-x: auto;
}
#ptable {
  display: grid;
  grid-template-columns: repeat(18, minmax(34px, 1fr));
  grid-template-rows: repeat(7, auto) 10px repeat(2, auto);
  gap: 4px;
  min-width: 760px;
}
.cell {
  position: relative; aspect-ratio: 1 / 1; min-height: 34px;
  border-radius: 7px; border: 1px solid rgba(255,255,255,.14);
  background: var(--cell, #2a3550);
  color: #0b0f1a; cursor: pointer; user-select: none;
  display: flex; flex-direction: column; justify-content: center; align-items: center;
  padding: 2px; transition: transform .08s ease, box-shadow .12s ease, filter .12s ease;
  overflow: hidden;
}
.cell .num { position: absolute; top: 2px; left: 4px; font-size: 9px; font-weight: 600; opacity: .8; }
.cell .sym { font-size: clamp(12px, 1.5vw, 17px); font-weight: 800; line-height: 1; }
.cell .nm { font-size: 7.5px; line-height: 1; margin-top: 2px; opacity: .85; max-width: 100%;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.cell .ms { font-size: 6.5px; opacity: .7; }
.cell:hover { transform: translateY(-2px) scale(1.06); z-index: 5; box-shadow: 0 8px 22px rgba(0,0,0,.5); filter: brightness(1.08); }
.cell.selected { outline: 3px solid #fff; outline-offset: -1px; box-shadow: 0 0 0 3px rgba(94,234,212,.5), 0 0 22px rgba(94,234,212,.6); z-index: 4; }
.cell.dim { opacity: .18; filter: grayscale(.6); }
.cell.search-hit { box-shadow: 0 0 0 3px var(--accent), 0 0 18px rgba(94,234,212,.7); }

/* The big focused-element card lives in the empty top-left zone of the table */
#focus-card {
  grid-column: 3 / 13; grid-row: 1 / 4;
  border-radius: 12px; border: 1px solid var(--line-strong);
  background: linear-gradient(160deg, rgba(255,255,255,.05), rgba(0,0,0,.18));
  padding: 12px 16px; display: flex; gap: 16px; align-items: stretch; overflow: hidden;
}
#focus-card .fc-symbol {
  flex: 0 0 auto; width: 116px; border-radius: 12px; display: flex; flex-direction: column;
  justify-content: center; align-items: center; color: #0b0f1a; position: relative;
}
#focus-card .fc-symbol .fc-num { position: absolute; top: 6px; left: 10px; font-weight: 700; font-size: 13px; }
#focus-card .fc-symbol .fc-sym { font-size: 46px; font-weight: 800; line-height: 1; }
#focus-card .fc-symbol .fc-mass { font-size: 12px; opacity: .85; margin-top: 4px; }
#focus-card .fc-body { flex: 1 1 auto; min-width: 0; display: flex; flex-direction: column; }
#focus-card .fc-name { font-size: 22px; font-weight: 800; }
#focus-card .fc-cat { font-size: 12px; color: var(--text-dim); margin-bottom: 6px; text-transform: capitalize; }
#focus-card .fc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 4px 14px; font-size: 11.5px; }
#focus-card .fc-grid div { color: var(--text-dim); }
#focus-card .fc-grid b { color: var(--text); font-weight: 600; }
#focus-card .fc-hint { margin-top: auto; font-size: 11px; color: var(--accent); }
#focus-card.empty .fc-body { justify-content: center; color: var(--text-faint); }
@media (max-width: 720px) { #focus-card { grid-column: 1 / 19; grid-row: 1 / 2; } }

/* Lanthanide / actinide pointer cells */
.marker-cell {
  display: flex; align-items: center; justify-content: center; font-size: 9px;
  color: var(--text-faint); border: 1px dashed var(--line-strong); border-radius: 7px; aspect-ratio: 1/1;
}

/* ---------- Legend ---------- */
#legend { display: flex; flex-wrap: wrap; gap: 8px 14px; margin-top: 14px; }
.legend-item { display: flex; align-items: center; gap: 6px; font-size: 11.5px; color: var(--text-dim); cursor: default; }
.legend-swatch { width: 12px; height: 12px; border-radius: 3px; }

/* ---------- Lab ---------- */
#lab {
  position: sticky; top: 12px;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 14px; display: flex; flex-direction: column; gap: 12px;
}
.lab-head { display: flex; align-items: center; justify-content: space-between; }
.lab-head h2 { font-size: 16px; }
.ghost-btn { background: transparent; border: 1px solid var(--line-strong); color: var(--text-dim);
  border-radius: 8px; padding: 5px 10px; cursor: pointer; font-size: 12px; }
.ghost-btn:hover { color: var(--text); border-color: var(--danger); }

.cauldron {
  position: relative; border-radius: 14px; min-height: 188px;
  background: radial-gradient(120% 90% at 50% 0%, rgba(129,140,248,.12), transparent 60%), rgba(0,0,0,.30);
  border: 2px dashed var(--line-strong); overflow: hidden; transition: border-color .15s, box-shadow .15s;
}
.cauldron.dragover { border-color: var(--accent); box-shadow: inset 0 0 30px rgba(94,234,212,.25); }
.cauldron #fx { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }
.cauldron-hint {
  position: absolute; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 6px; color: var(--text-faint); text-align: center; font-size: 12px; pointer-events: none; padding: 10px;
}
.cauldron-hint .big { font-size: 30px; opacity: .5; }
.cauldron.has-items .cauldron-hint { display: none; }
.tray { position: absolute; inset: 0; display: flex; flex-wrap: wrap; gap: 6px; align-content: flex-start;
  padding: 10px; overflow: auto; }
.chip {
  display: inline-flex; align-items: center; gap: 5px; padding: 4px 6px 4px 8px;
  border-radius: 9px; font-size: 13px; font-weight: 700; color: #0b0f1a; cursor: default;
  box-shadow: 0 4px 12px rgba(0,0,0,.4); animation: pop .18s ease;
}
.chip .chip-count { font-size: 10px; background: rgba(0,0,0,.28); color: #fff; border-radius: 6px; padding: 1px 4px; }
.chip .chip-x { cursor: pointer; opacity: .7; font-weight: 800; }
.chip .chip-x:hover { opacity: 1; }
@keyframes pop { from { transform: scale(.6); opacity: 0; } to { transform: scale(1); opacity: 1; } }

/* Thermometer */
.thermo { background: rgba(0,0,0,.2); border: 1px solid var(--line); border-radius: 12px; padding: 10px 12px; }
.thermo-row { display: flex; align-items: center; justify-content: space-between; }
.thermo-label { font-size: 13px; font-weight: 600; }
.thermo-readout { font-size: 12px; color: var(--accent); font-variant-numeric: tabular-nums; }
#temp { width: 100%; margin: 8px 0 6px; accent-color: var(--accent); }
input[type=range]#temp {
  -webkit-appearance: none; height: 6px; border-radius: 6px;
  background: linear-gradient(90deg, #38bdf8, #5eead4 30%, #fbbf24 70%, #fb7185);
}
input[type=range]#temp::-webkit-slider-thumb {
  -webkit-appearance: none; width: 18px; height: 18px; border-radius: 50%;
  background: #fff; border: 2px solid #0b0f1a; cursor: pointer; box-shadow: 0 2px 8px rgba(0,0,0,.5);
}
.thermo-quick { gap: 4px; flex-wrap: wrap; justify-content: flex-start; margin-top: 4px; }
.chip-btn { background: rgba(255,255,255,.06); border: 1px solid var(--line); color: var(--text-dim);
  border-radius: 7px; padding: 4px 7px; font-size: 11px; cursor: pointer; }
.chip-btn:hover { color: var(--text); border-color: var(--accent); }
.state-readout { margin-top: 8px; font-size: 11.5px; color: var(--text-dim); min-height: 16px; }
.state-readout b { color: var(--text); }

/* Reagents */
.reagents { display: flex; gap: 8px; }
.reagent-btn { flex: 1; background: rgba(255,255,255,.05); border: 1px solid var(--line-strong);
  color: var(--text); border-radius: 10px; padding: 9px 6px; cursor: pointer; font-size: 12px; transition: .12s; }
.reagent-btn:hover { border-color: var(--accent); background: rgba(94,234,212,.1); }
.reagent-btn.active { border-color: var(--accent); background: rgba(94,234,212,.18); box-shadow: 0 0 0 2px rgba(94,234,212,.2); }

/* Mix button */
.mix-btn {
  background: linear-gradient(120deg, var(--accent), var(--accent-2)); color: #061018; font-weight: 800;
  border: none; border-radius: 12px; padding: 13px; font-size: 15px; cursor: pointer; letter-spacing: .3px;
  box-shadow: 0 8px 24px rgba(94,234,212,.25); transition: transform .08s, filter .12s;
}
.mix-btn:hover:not(:disabled) { filter: brightness(1.06); }
.mix-btn:active:not(:disabled) { transform: translateY(1px); }
.mix-btn:disabled { opacity: .4; cursor: not-allowed; box-shadow: none; }

/* Result card */
.result:empty { display: none; }
.result {
  border-radius: 12px; border: 1px solid var(--line-strong); padding: 12px 14px; background: rgba(0,0,0,.25);
  animation: rise .25s ease;
}
@keyframes rise { from { transform: translateY(8px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
.result .r-head { display: flex; align-items: center; gap: 8px; margin-bottom: 4px; }
.result .r-emoji { font-size: 22px; }
.result .r-title { font-size: 15px; font-weight: 800; }
.result .r-eq { font-size: 13px; font-family: ui-monospace, "SF Mono", Menlo, monospace; color: var(--accent);
  background: rgba(94,234,212,.08); border-radius: 7px; padding: 5px 8px; margin: 6px 0; overflow-x: auto; white-space: nowrap; }
.result .r-eq sub { font-size: .8em; }
.result .r-desc { font-size: 12.5px; color: var(--text-dim); }
.result .r-desc b { color: var(--text); }
.result .r-fact { font-size: 11.5px; color: var(--text-faint); margin-top: 6px; border-top: 1px solid var(--line); padding-top: 6px; }
.hazard { display: flex; align-items: center; gap: 6px; margin-top: 8px; font-size: 11px; color: var(--text-dim); }
.hazard-bar { flex: 1; height: 6px; border-radius: 6px; background: rgba(255,255,255,.08); overflow: hidden; }
.hazard-fill { height: 100%; border-radius: 6px; background: linear-gradient(90deg, var(--ok), var(--warn), var(--danger)); }
.tag { display: inline-block; font-size: 10px; font-weight: 700; padding: 2px 7px; border-radius: 20px; margin: 4px 4px 0 0; }

/* Thermodynamics panel + energy diagram */
.thermo-block { margin: 10px 0; padding: 9px 11px; border-radius: 10px; background: rgba(94,234,212,.05); border: 1px solid var(--line); }
.thermo-block .dp-section-title { margin: 0 0 6px; }
.energy-svg { width: 100%; height: auto; display: block; margin-bottom: 8px; }
.es-lbl { fill: var(--text-dim); font-size: 9px; font-family: inherit; }
.es-lbl.dim { fill: var(--text-faint); }
.thermo-line { font-size: 12px; color: var(--text-dim); margin: 2px 0; font-variant-numeric: tabular-nums; }
.thermo-line b { color: var(--text); }
.thermo-line sub { font-size: .78em; }
.thermo-cross { font-size: 11px; color: var(--text-faint); margin-top: 5px; }
.thermo-cross b { color: var(--accent); }
.exo { color: #fb923c; font-weight: 600; }
.endo { color: #38bdf8; font-weight: 600; }
.spont { color: var(--ok); font-weight: 600; }
.nonspont { color: var(--danger); font-weight: 600; }
.r-hint { margin-top: 9px; font-size: 12.5px; color: var(--text); background: rgba(129,140,248,.12); border: 1px solid rgba(129,140,248,.35); border-radius: 9px; padding: 8px 11px; }
.r-hint b { color: var(--accent-2); }

/* Discoveries */
.discoveries h3 { font-size: 13px; color: var(--text-dim); display: flex; align-items: center; gap: 6px; }
.discoveries #disc-count { background: rgba(94,234,212,.15); color: var(--accent); border-radius: 20px; padding: 1px 8px; font-size: 11px; }
#disc-list { list-style: none; margin: 8px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 6px; }
#disc-list li { font-size: 11px; background: rgba(255,255,255,.05); border: 1px solid var(--line); border-radius: 7px;
  padding: 4px 8px; color: var(--text-dim); }
#disc-list li b { color: var(--text); }
#disc-list:empty::after { content: "Mix elements to discover compounds…"; color: var(--text-faint); font-size: 11px; }

/* ---------- Footer ---------- */
#footer { margin: 18px 4px 24px; font-size: 11px; color: var(--text-faint); display: flex; flex-direction: column; gap: 3px; }
.footer-warn { color: #8a7a5a; }

/* ---------- Modal (3D explorer) ---------- */
.modal { position: fixed; inset: 0; z-index: 100; display: none; }
.modal.open { display: block; }
.modal-backdrop { position: absolute; inset: 0; background: rgba(4,7,14,.7); backdrop-filter: blur(4px); }
.modal-card {
  position: absolute; inset: 3% 4%; max-width: 1180px; margin: auto; height: 92%;
  background: var(--panel-solid); border: 1px solid var(--line-strong); border-radius: 18px;
  box-shadow: var(--shadow); overflow: hidden;
}
.modal-close { position: absolute; top: 12px; right: 14px; z-index: 6; width: 34px; height: 34px; border-radius: 9px;
  background: rgba(0,0,0,.35); border: 1px solid var(--line-strong); color: var(--text); cursor: pointer; font-size: 14px; }
.modal-close:hover { border-color: var(--danger); }
.modal-nav { position: absolute; top: 50%; transform: translateY(-50%); z-index: 6; width: 38px; height: 54px;
  background: rgba(0,0,0,.35); border: 1px solid var(--line-strong); color: var(--text); cursor: pointer;
  font-size: 24px; border-radius: 10px; }
.modal-nav.prev { left: 10px; } .modal-nav.next { right: 10px; }
.modal-nav:hover { border-color: var(--accent); }
.modal-grid { display: grid; grid-template-columns: 1.15fr 1fr; height: 100%; }
@media (max-width: 860px) { .modal-grid { grid-template-columns: 1fr; grid-template-rows: 1fr 1fr; }
  .modal-card { inset: 2%; height: 96%; } }
.atom-pane { position: relative; background: radial-gradient(120% 120% at 50% 30%, #0e1730, #060912); }
.atom-canvas { position: absolute; inset: 0; }
.atom-canvas canvas { display: block; }
.atom-controls { position: absolute; left: 12px; bottom: 12px; display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.mini-btn { background: rgba(0,0,0,.4); border: 1px solid var(--line-strong); color: var(--text);
  border-radius: 8px; padding: 6px 10px; font-size: 12px; cursor: pointer; }
.mini-btn[aria-pressed="true"] { border-color: var(--accent); color: var(--accent); }
.atom-hint { font-size: 11px; color: var(--text-faint); }
.atom-badges { position: absolute; left: 12px; top: 12px; display: flex; flex-direction: column; gap: 4px; }

/* Atom HTML annotation labels (projected from 3D) */
.atom-label { position: absolute; transform: translate(-50%, -50%); pointer-events: none;
  font-size: 11px; color: #dfe8ff; white-space: nowrap; text-shadow: 0 1px 4px #000;
  background: rgba(8,12,22,.55); border: 1px solid rgba(255,255,255,.15); border-radius: 6px; padding: 1px 6px; }
.atom-label.valence { color: #fde68a; border-color: rgba(251,191,36,.5); }
.atom-label.nucleus { color: #fca5a5; border-color: rgba(248,113,113,.5); }

.data-pane { overflow-y: auto; padding: 20px 22px; }
.dp-title { display: flex; align-items: baseline; gap: 10px; }
.dp-title h2 { font-size: 26px; }
.dp-title .dp-sym { font-size: 14px; color: var(--text-dim); }
.dp-cat { font-size: 12px; text-transform: capitalize; margin: 2px 0 14px; }
.dp-cat .dot { display: inline-block; width: 9px; height: 9px; border-radius: 3px; margin-right: 6px; vertical-align: middle; }
.dp-summary { font-size: 13px; color: var(--text-dim); line-height: 1.55; margin-bottom: 14px; }
.dp-section-title { font-size: 11px; text-transform: uppercase; letter-spacing: .8px; color: var(--text-faint); margin: 16px 0 8px; }
.dp-props { display: grid; grid-template-columns: 1fr 1fr; gap: 6px 14px; }
.dp-prop { font-size: 12.5px; display: flex; justify-content: space-between; gap: 10px; border-bottom: 1px dotted var(--line); padding-bottom: 4px; }
.dp-prop span { color: var(--text-dim); } .dp-prop b { color: var(--text); font-weight: 600; text-align: right; }
.dp-config { font-family: ui-monospace, Menlo, monospace; font-size: 12px; color: var(--accent);
  background: rgba(94,234,212,.07); border-radius: 8px; padding: 8px 10px; word-break: break-word; }
.dp-image { margin-top: 8px; }
.dp-image img { width: 100%; border-radius: 10px; border: 1px solid var(--line); display: block; background: #000; }
.dp-image figcaption { font-size: 10.5px; color: var(--text-faint); margin-top: 4px; }
.dp-shells-svg { width: 100%; height: auto; }
.dp-add { margin-top: 16px; display: flex; gap: 8px; }
.dp-add button { flex: 1; border-radius: 10px; padding: 10px; border: 1px solid var(--line-strong);
  background: rgba(255,255,255,.05); color: var(--text); cursor: pointer; font-size: 13px; font-weight: 600; }
.dp-add button:hover { border-color: var(--accent); background: rgba(94,234,212,.1); }

/* Help */
.help-card { position: absolute; inset: 6% 8%; max-width: 620px; margin: auto; height: max-content; max-height: 88%;
  overflow: auto; background: var(--panel-solid); border: 1px solid var(--line-strong); border-radius: 18px;
  padding: 26px 28px; box-shadow: var(--shadow); }
.help-card h2 { font-size: 20px; margin-bottom: 14px; }
.help-list { margin: 0; padding-left: 20px; display: flex; flex-direction: column; gap: 9px; font-size: 13.5px; color: var(--text-dim); }
.help-list b { color: var(--text); }
.help-foot { margin-top: 16px; font-size: 12.5px; color: var(--accent); }

/* Screen-flash for explosions */
#flash { position: fixed; inset: 0; background: #fff; opacity: 0; pointer-events: none; z-index: 200; }
.shake { animation: shake .5s; }
@keyframes shake {
  0%,100% { transform: translate(0,0); } 10% { transform: translate(-6px, 4px); }
  30% { transform: translate(8px, -4px); } 50% { transform: translate(-7px, -3px); }
  70% { transform: translate(6px, 5px); } 90% { transform: translate(-4px, 2px); }
}

/* Scrollbars */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,.12); border-radius: 8px; }
::-webkit-scrollbar-track { background: transparent; }