/* Brain Teaser quiz (products/miscellaneous/brain-teaser). Uses the site's palette. */
#brain-teaser-app { margin: 1.5rem 0 3rem; scroll-margin-top: 1rem; }
.bt-card { background: #fdfbf6; border: 1px solid #ddd6c9; border-radius: 8px; padding: 1.25rem 1.5rem; }
.bt-muted { color: #6b6155; font-size: 0.95rem; }
.bt-list li { margin: 0.4rem 0; }
.bt-btn { padding: 0.55rem 1.4rem; font: inherit; font-weight: bold; color: #f9f6f0; background: #9a7b4f; border: none; border-radius: 5px; cursor: pointer; margin-top: 0.75rem; }
.bt-btn:hover { background: #7d6340; }
.bt-btn:focus-visible, .bt-choice:focus-visible { outline: 3px solid #332e28; outline-offset: 2px; }
.bt-ghost { background: transparent; color: #7d6340; border: 1px solid #c9b99a; }
.bt-ghost:hover { background: #f1ebdf; }
.bt-head { display: flex; justify-content: space-between; font-size: 0.9rem; color: #6b6155; }
.bt-cat { font-weight: bold; color: #7d6340; }
.bt-progress { height: 4px; background: #ece5d8; border-radius: 2px; margin: 0.4rem 0 1rem; }
.bt-progress div { height: 100%; background: #9a7b4f; border-radius: 2px; }
.bt-prompt { font-size: 1.08rem; margin-bottom: 1rem; }
.bt-visual { text-align: center; margin: 0.5rem 0 1rem; }
.bt-visual svg { max-width: 100%; height: auto; }
.bt-choices { display: grid; grid-template-columns: 1fr; gap: 0.5rem; }
.bt-choices-visual { grid-template-columns: repeat(auto-fit, minmax(110px, 1fr)); }
.bt-choice { display: flex; align-items: center; gap: 0.7rem; text-align: left; font: inherit; color: inherit; background: #fff; border: 1px solid #c9b99a; border-radius: 6px; padding: 0.6rem 0.8rem; cursor: pointer; }
.bt-choices-visual .bt-choice { flex-direction: column; justify-content: center; }
.bt-choice svg { max-width: 100%; height: auto; }
.bt-choice:hover:not(:disabled) { background: #f6f0e4; }
.bt-choice:disabled { cursor: default; opacity: 0.85; }
.bt-key { flex: none; width: 1.6rem; height: 1.6rem; border-radius: 50%; background: #ece5d8; display: inline-flex; align-items: center; justify-content: center; font-size: 0.8rem; font-weight: bold; }
.bt-right { border: 2px solid #4f6b3a; background: #eef4e8; opacity: 1 !important; }
.bt-wrong { border: 2px solid #8a3b2e; background: #f8e9e6; }
.bt-explain { margin-top: 1rem; padding: 0.8rem 1rem; border-radius: 6px; border-left: 4px solid #c9b99a; background: #f6f0e4; }
.bt-explain.ok { border-left-color: #4f6b3a; } .bt-explain.no { border-left-color: #8a3b2e; }
.bt-verdict { font-weight: bold; margin: 0 0 0.4rem; }
.bt-level { font-weight: normal; color: #6b6155; font-size: 0.9rem; }
.bt-io { display: flex; flex-wrap: wrap; gap: 0.6rem 1.4rem; margin: 0.6rem 0; font-size: 1.05rem; }
.bt-study { min-height: 7rem; display: flex; flex-direction: column; justify-content: center; align-items: center; text-align: center; }
.bt-blank { color: #c9b99a; font-size: 2rem; }
.bt-big { font-size: 1.9rem; letter-spacing: 0.04em; font-weight: bold; margin: 0.5rem 0; }
.bt-step { color: #6b6155; font-size: 0.9rem; }
.bt-timer { height: 6px; background: #ece5d8; border-radius: 3px; overflow: hidden; margin: 1rem 0 0.5rem; }
.bt-timer div { height: 100%; width: 100%; background: #9a7b4f; }
.bt-lex { border-collapse: collapse; margin: 0.5rem auto; } .bt-lex td { padding: 0.2rem 0.9rem; border-bottom: 1px solid #ece5d8; text-align: left; }
.bt-trial { min-height: 6rem; display: flex; justify-content: center; align-items: center; margin: 1rem 0; border-radius: 6px; transition: background 0.15s; }
.bt-flash-no { background: #f8e9e6; }
.bt-pair { display: flex; flex-direction: column; gap: 0.4rem; font-size: 1.9rem; letter-spacing: 0.15em; text-align: center; }
.bt-yn { display: flex; gap: 1rem; justify-content: center; }
.bt-yn .bt-btn { min-width: 8rem; }
kbd { font-family: inherit; font-size: 0.75em; border: 1px solid currentColor; border-radius: 3px; padding: 0 0.3em; opacity: 0.8; }
.bt-cell { fill: #9a7b4f; stroke: #332e28; stroke-width: 1; }
.bt-face { fill: #fdfbf6; stroke: #332e28; stroke-width: 1.5; }
.bt-sym { font-size: 22px; fill: #332e28; }
.bt-frame { fill: #fff; stroke: #c9b99a; } .bt-missing { fill: #f6f0e4; stroke: #9a7b4f; stroke-dasharray: 4 3; } .bt-q { font-size: 26px; fill: #9a7b4f; font-weight: bold; }
.bt-matrix-cell { background: #fff; }
.bt-kicker { text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.8rem; color: #9a7b4f; margin: 0; }
.bt-results h2 { margin: 0.2rem 0 0.4rem; }
.bt-table { width: 100%; border-collapse: collapse; margin: 1rem 0; font-size: 0.95rem; }
.bt-table th, .bt-table td { text-align: left; padding: 0.45rem 0.4rem; border-bottom: 1px solid #ece5d8; vertical-align: middle; }
.bt-pill { display: inline-block; padding: 0.05rem 0.45rem; border-radius: 10px; font-size: 0.8rem; font-weight: bold; }
.bt-pill.ok { background: #eef4e8; color: #4f6b3a; } .bt-pill.no { background: #f8e9e6; color: #8a3b2e; }
.bt-lr { min-width: 9rem; }
.bt-meter { display: inline-block; width: 5rem; height: 6px; background: #ece5d8; border-radius: 3px; vertical-align: middle; margin-right: 0.4rem; }
.bt-meter div { height: 100%; background: #9a7b4f; border-radius: 3px; }
.bt-band { font-size: 0.85rem; font-weight: bold; color: #7d6340; }
.bt-lr-m { display: none; }
@media (max-width: 600px) {
  .bt-card { padding: 1rem; } .bt-big { font-size: 1.5rem; } .bt-pair { font-size: 1.5rem; }
  .bt-table th:nth-child(3), .bt-table td:nth-child(3) { display: none; }
  .bt-lr-m { display: block; margin-top: 0.25rem; font-size: 0.85rem; }
}
.bt-choices-sym .bt-choice > span:last-child { font-size: 1.9rem; line-height: 1.2; }
.bt-study ul, .bt-study ol { display: inline-block; text-align: left; margin: 0.5rem auto; }