/* Bonding lab — Lewis builder, VSEPR, sorter, polarity, concepts, sprint */

.bonding-lab {
  --bl-accent: var(--chip-chemistry);
  --bl-accent2: #e8a83a;
  --bl-cool: #5ba8b0;
  --bl-muted: var(--color-text-muted);
  --bl-ok: var(--chip-biology);
  --bl-bad: #e07070;
  max-width: 920px;
  font-family: var(--font-body);
}

/* header */
.bonding-lab__header { margin-bottom: var(--space-6); }
.bonding-lab__eyebrow {
  font-size: var(--text-xs); font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--bl-accent); margin-bottom: var(--space-2);
}
.bonding-lab__title {
  font-family: var(--font-display); font-size: var(--text-lg); font-weight: 700;
  letter-spacing: -0.02em; line-height: 1.25; margin-bottom: var(--space-3);
}
.bonding-lab__intro {
  font-size: var(--text-sm); color: var(--bl-muted); line-height: 1.65; max-width: 58ch;
}

/* tabs */
.bonding-lab__tabs { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-bottom: var(--space-6); }
.bonding-lab__tab {
  font-family: var(--font-body); font-size: var(--text-xs); font-weight: 600;
  padding: 0.5rem 1rem; border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  background: oklch(from var(--color-text) l c h / 0.04);
  color: var(--bl-muted); cursor: pointer;
  transition: background var(--transition-interactive), color var(--transition-interactive),
              border-color var(--transition-interactive), box-shadow var(--transition-interactive);
}
.bonding-lab__tab:hover { color: var(--color-text); border-color: oklch(from var(--bl-accent) l c h / 0.45); }
.bonding-lab__tab[aria-selected="true"] {
  color: var(--color-bg); background: var(--bl-accent); border-color: var(--bl-accent);
  box-shadow: 0 0 20px oklch(from var(--bl-accent) l c h / 0.28);
}

/* panels */
.bonding-lab__panel { display: none; animation: bl-fade-in 0.4s cubic-bezier(0.16, 1, 0.3, 1) both; }
.bonding-lab__panel.is-active { display: block; }
@keyframes bl-fade-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: translateY(0); } }
@media (prefers-reduced-motion: reduce) { .bonding-lab__panel { animation: none; } }

.bonding-lab__section-label {
  font-size: var(--text-xs); font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.1em; color: var(--color-text-faint); margin-bottom: var(--space-4);
}

/* shared feedback */
.bonding-lab__feedback { font-size: var(--text-sm); font-weight: 600; min-height: 1.4em; margin-top: var(--space-3); }
.bonding-lab__feedback--ok { color: var(--bl-ok); }
.bonding-lab__feedback--bad { color: var(--bl-bad); }

/* shared btns */
.bonding-lab__btn-row { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-4); }
.bonding-lab__btn {
  font-family: var(--font-body); font-weight: 600; font-size: var(--text-sm);
  padding: 0.55rem 1.1rem; border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  background: oklch(from var(--color-text) l c h / 0.06);
  color: var(--color-text); cursor: pointer;
  transition: background var(--transition-interactive), border-color var(--transition-interactive);
}
.bonding-lab__btn:hover { border-color: oklch(from var(--bl-accent) l c h / 0.5); }
.bonding-lab__btn--primary {
  background: var(--bl-accent); border-color: var(--bl-accent); color: var(--color-bg);
}
.bonding-lab__btn--primary:hover { filter: brightness(1.08); }

/* ── Lewis Builder ─────────────────────────────── */

.bonding-lab__lewis-card {
  border-radius: var(--radius-xl); border: 1px solid var(--color-border);
  padding: var(--space-6); background: var(--color-surface);
}
.bonding-lab__lewis-head {
  display: flex; flex-wrap: wrap; align-items: baseline;
  justify-content: space-between; gap: var(--space-3); margin-bottom: var(--space-4);
}
.bonding-lab__lewis-formula {
  font-family: var(--font-mono); font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 600; color: var(--bl-accent);
}
.bonding-lab__lewis-counter {
  font-family: var(--font-mono); font-size: var(--text-sm); color: var(--bl-muted);
}
.bonding-lab__lewis-counter strong { color: var(--bl-accent); }
.bonding-lab__lewis-instr {
  font-size: var(--text-sm); color: var(--bl-muted); line-height: 1.55; margin-bottom: var(--space-3);
}

/* molecule canvas area */
.bonding-lab__mol-display {
  position: relative; width: 100%; border-radius: var(--radius-xl);
  border: 1px solid var(--color-border); background: var(--color-surface);
  overflow: hidden; margin-bottom: var(--space-4); min-height: 220px;
}

/* atom circles */
.bonding-lab__atom {
  position: absolute; transform: translate(-50%, -50%);
  width: 52px; height: 52px; border-radius: 50%;
  background: oklch(from var(--atom-color, #888) l c h / 0.2);
  border: 2px solid oklch(from var(--atom-color, #888) l c h / 0.55);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  cursor: pointer; z-index: 2;
  transition: box-shadow var(--transition-interactive), transform var(--transition-interactive);
}
.bonding-lab__atom:hover {
  box-shadow: 0 0 16px oklch(from var(--bl-accent) l c h / 0.35);
  transform: translate(-50%, -50%) scale(1.08);
}
.bonding-lab__atom-label {
  font-family: var(--font-mono); font-size: 0.95rem; font-weight: 600;
  color: var(--color-text); pointer-events: none;
}
.bonding-lab__lone-count {
  font-size: 0.6rem; font-weight: 700; color: var(--bl-accent2);
  background: oklch(from var(--bl-accent2) l c h / 0.18);
  padding: 1px 5px; border-radius: var(--radius-full);
  position: absolute; top: -8px; right: -10px;
}

/* bond clickable regions */
.bonding-lab__bond-region {
  position: absolute; transform: translate(-50%, -50%);
  width: 60px; height: 30px; cursor: pointer; z-index: 1;
  display: flex; align-items: center; justify-content: center;
  border-radius: var(--radius-md);
  transition: background var(--transition-interactive);
}
.bonding-lab__bond-region:hover {
  background: oklch(from var(--bl-accent) l c h / 0.1);
}
.bonding-lab__bond-line {
  width: 40px; height: 2.5px; background: var(--bl-accent);
  border-radius: 2px; position: absolute;
}
.bonding-lab__bond-label {
  font-family: var(--font-mono); font-size: 1.1rem; font-weight: 700;
  color: var(--bl-accent); pointer-events: none;
}

/* ── VSEPR Shapes ──────────────────────────────── */

.bonding-lab__vsepr-card {
  border-radius: var(--radius-xl); border: 1px solid var(--color-border);
  padding: var(--space-6); background: var(--color-surface);
}
.bonding-lab__vsepr-mol {
  font-family: var(--font-mono); font-size: clamp(1.2rem, 3vw, 1.6rem);
  font-weight: 600; color: var(--bl-accent); margin-bottom: var(--space-2);
}
.bonding-lab__vsepr-name {
  font-family: var(--font-body); font-size: var(--text-sm);
  font-weight: 400; color: var(--bl-muted); margin-left: var(--space-2);
}
.bonding-lab__vsepr-info {
  font-size: var(--text-sm); color: var(--bl-muted); margin-bottom: var(--space-5);
}
.bonding-lab__vsepr-shapes {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: var(--space-3); margin-bottom: var(--space-4);
}
.bonding-lab__shape-btn {
  display: flex; flex-direction: column; align-items: center; gap: var(--space-2);
  padding: var(--space-4); border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: oklch(from var(--color-text) l c h / 0.03);
  cursor: pointer; font-family: var(--font-body); font-size: var(--text-sm);
  color: var(--color-text); text-align: center;
  transition: border-color var(--transition-interactive), background var(--transition-interactive);
}
.bonding-lab__shape-btn:hover:not(:disabled) {
  border-color: oklch(from var(--bl-accent) l c h / 0.5);
  background: oklch(from var(--bl-accent) l c h / 0.06);
}
.bonding-lab__shape-btn:disabled { cursor: default; opacity: 0.88; }
.bonding-lab__shape-btn--correct {
  border-color: var(--bl-ok); background: oklch(from var(--bl-ok) l c h / 0.1);
}
.bonding-lab__shape-btn--wrong {
  border-color: var(--bl-bad); background: oklch(from var(--bl-bad) l c h / 0.08);
}

.bonding-lab__shape-icon {
  width: 48px; height: 48px; display: block;
  background: oklch(from var(--bl-accent) l c h / 0.12);
  border-radius: var(--radius-md); position: relative;
}
.bonding-lab__shape-icon::after {
  content: ''; position: absolute; inset: 6px;
  border: 2px solid oklch(from var(--bl-accent) l c h / 0.4);
  border-radius: 2px;
}
.bonding-lab__shape-icon[data-shape="linear"]::after { border-radius: 0; height: 2px; top: 50%; }
.bonding-lab__shape-icon[data-shape="bent"]::after { border-radius: 0 0 8px 8px; border-top: none; height: 50%; top: 25%; }
.bonding-lab__shape-icon[data-shape="tetrahedral"]::after { clip-path: polygon(50% 5%, 10% 95%, 90% 95%); }
.bonding-lab__shape-icon[data-shape="trigonal-pyramidal"]::after { clip-path: polygon(50% 15%, 15% 85%, 85% 85%); }
.bonding-lab__shape-icon[data-shape="octahedral"]::after { clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%); }

/* ── Polarity Check ────────────────────────────── */

.bonding-lab__polarity-card {
  border-radius: var(--radius-xl); border: 1px solid var(--color-border);
  padding: var(--space-6); background: var(--color-surface);
}
.bonding-lab__polarity-mol {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: var(--space-3) var(--space-5);
  margin-bottom: var(--space-5);
}
.bonding-lab__polarity-name {
  font-family: var(--font-mono); font-size: clamp(1.25rem, 3vw, 1.6rem);
  font-weight: 600; color: var(--bl-accent);
}
.bonding-lab__polarity-shape,
.bonding-lab__polarity-dipoles {
  font-size: var(--text-sm); color: var(--bl-muted);
  padding: 0.3rem 0.7rem; border-radius: var(--radius-full);
  background: oklch(from var(--color-text) l c h / 0.05);
  border: 1px solid var(--color-border);
}
.bonding-lab__polarity-btns {
  display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-3); margin-bottom: var(--space-4);
}
@media (max-width: 480px) { .bonding-lab__polarity-btns { grid-template-columns: 1fr; } }
.bonding-lab__polar-btn {
  font-family: var(--font-body); font-size: var(--text-sm); font-weight: 600;
  padding: var(--space-5); border-radius: var(--radius-md);
  border: 2px solid var(--color-border); background: oklch(from var(--color-text) l c h / 0.03);
  color: var(--color-text); cursor: pointer; text-align: center;
  transition: border-color var(--transition-interactive), background var(--transition-interactive);
}
.bonding-lab__polar-btn:hover:not(:disabled) {
  border-color: oklch(from var(--bl-accent) l c h / 0.5);
  background: oklch(from var(--bl-accent) l c h / 0.06);
}
.bonding-lab__polar-btn:disabled { cursor: default; opacity: 0.88; }
.bonding-lab__polar-btn--correct {
  border-color: var(--bl-ok); background: oklch(from var(--bl-ok) l c h / 0.1);
}
.bonding-lab__polar-btn--wrong {
  border-color: var(--bl-bad); background: oklch(from var(--bl-bad) l c h / 0.08);
}
.bonding-lab__polarity-reveal {
  margin-top: var(--space-4); padding: var(--space-4);
  border-radius: var(--radius-md);
  background: oklch(from var(--bl-cool) l c h / 0.08);
  border: 1px solid oklch(from var(--bl-cool) l c h / 0.2);
}
.bonding-lab__polarity-why {
  font-size: var(--text-sm); color: var(--bl-muted); line-height: 1.6;
}