/* Brain Power: the quiz board, mode cards, category picker, and clue card. Base colors and type come from base.css. */
:root { --board: #1C2321; --tile: #262E2B; --tile-ink: #F2C94C; --tile-done: #1F2523; --good: #2F7A4A; --good-bg: #E6F2EA; --bad-bg: #F8E6E4; --on-accent: #FFFFFF; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --board: #0E1110; --tile: #1F2624; --tile-done: #161A19; --good: #6CC08A; --good-bg: #1D2E23; --bad-bg: #33201E; --on-accent: #141817; }
}
:root[data-theme="dark"] { --board: #0E1110; --tile: #1F2624; --tile-done: #161A19; --good: #6CC08A; --good-bg: #1D2E23; --bad-bg: #33201E; --on-accent: #141817; }
* { box-sizing: border-box; }
[hidden] { display: none !important; }
.wrap { max-width: 64rem; margin: 0 auto; padding-left: max(20px, env(safe-area-inset-left, 0px)); padding-right: max(20px, env(safe-area-inset-right, 0px)); }
.bp-top .wrap { padding-block: 1.4rem 0; display: flex; justify-content: space-between; align-items: baseline; gap: 1rem; flex-wrap: wrap; }
.crumb { font-family: var(--mono); font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin: 0; }
.intro { padding-block: 2.5rem 1.5rem; display: grid; gap: .6rem; }
h1 { font-family: var(--display); font-weight: 300; font-size: clamp(2.1rem, 5.5vw, 3.3rem); letter-spacing: -.03em; line-height: 1.05; margin: 0 0 .3rem; text-wrap: balance; }
h1 em { font-style: normal; color: var(--scarlet); }
.lede { margin: 0; color: var(--soft); max-width: 72ch; }
button:focus-visible { outline: 2px solid var(--scarlet); outline-offset: 3px; }

/* modes */
.modes { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: .7rem; margin-top: .5rem; }
@media (max-width: 640px) { .modes { grid-template-columns: minmax(0, 1fr); } }
.mode { text-align: left; font: inherit; color: var(--ink); background: var(--card); border: 1px solid var(--rule); border-radius: 14px; padding: .9rem 1rem; cursor: pointer; display: grid; gap: .15rem; }
.mode b { font-family: var(--display); font-weight: 500; font-size: 1.15rem; }
.mode span { font-size: .85rem; color: var(--soft); }
.mode[aria-pressed="true"] { border-color: var(--scarlet); box-shadow: inset 0 0 0 1px var(--scarlet); }

/* picker */
.picker { margin-top: 1rem; }
.picker summary { cursor: pointer; font-size: .9rem; color: var(--soft); }
.picker .help { font-size: .85rem; color: var(--muted); margin: .6rem 0; }
.cats { display: flex; flex-wrap: wrap; gap: .45rem; }
.cat { font: 400 .85rem var(--body); border: 1px solid var(--rule); background: transparent; color: var(--soft); border-radius: 999px; padding: .35rem .8rem; cursor: pointer; }
.cat[data-s="know"] { border-color: var(--good); color: var(--good); background: var(--good-bg); }
.cat[data-s="learn"] { border-color: var(--scarlet); color: var(--scarlet); background: var(--bad-bg); }
.cat small { font-family: var(--mono); font-size: .6rem; letter-spacing: .06em; text-transform: uppercase; margin-left: .35rem; }

/* board */
.stage { margin-top: 1.6rem; padding-bottom: 4rem; }
.scorebar { display: flex; justify-content: space-between; align-items: baseline; gap: 1rem; flex-wrap: wrap; margin-bottom: .7rem; }
.scorebar .label { font-family: var(--mono); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.score { font-family: var(--display); font-weight: 500; font-size: 1.6rem; font-variant-numeric: tabular-nums; }
.score.neg { color: var(--scarlet); }
.board { background: var(--board); border-radius: 16px; padding: .5rem; display: grid; gap: .4rem; overflow-x: auto; }
.bhead, .brow { display: grid; gap: .4rem; }
.bhead div { color: #FCFCFA; font-family: var(--display); font-weight: 500; font-size: clamp(.7rem, 1.6vw, .95rem); text-transform: uppercase; letter-spacing: .04em; text-align: center; padding: .7rem .3rem; display: grid; place-items: center; min-height: 3.6rem; line-height: 1.15; border-bottom: 2px solid var(--lane); }
.tile { font-family: var(--display); font-weight: 700; font-size: clamp(1.1rem, 3vw, 1.8rem); color: var(--tile-ink); background: var(--tile); border: 0; border-radius: 8px; min-height: 4rem; cursor: pointer; font-variant-numeric: tabular-nums; }
.tile:hover:not(:disabled) { filter: brightness(1.25); }
.tile:disabled { background: var(--tile-done); cursor: default; font-size: 1.1rem; }
.tile.right { color: #6CC08A; }
.tile.wrong { color: #F0776D; }

/* clue */
.clue { border: 1px solid var(--rule); border-radius: 16px; background: var(--card); padding: clamp(1.2rem, 3vw, 2rem); display: grid; gap: 1.1rem; }
.clue .meta { display: flex; justify-content: space-between; gap: 1rem; font-family: var(--mono); font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.clue .meta b { color: var(--scarlet); font-weight: 400; }
.clue .q { font-family: var(--display); font-weight: 400; font-size: clamp(1.35rem, 3.2vw, 1.85rem); line-height: 1.25; letter-spacing: -.01em; margin: 0; text-wrap: balance; }
.opts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .6rem; }
@media (max-width: 520px) { .opts { grid-template-columns: minmax(0, 1fr); } }
.opt { font: 400 1rem var(--body); text-align: left; padding: .8rem 1rem; border-radius: 12px; border: 1px solid var(--rule); background: var(--bg); color: var(--ink); cursor: pointer; }
.opt:hover:not(:disabled) { border-color: var(--muted); }
.opt.right { background: var(--good-bg); border-color: var(--good); }
.opt.wrong { background: var(--bad-bg); border-color: var(--scarlet); }
.opt:disabled { cursor: default; }
.why { margin: 0; padding: .8rem 1rem; border-radius: 12px; background: var(--bg); border-left: 3px solid var(--lane); color: var(--soft); }
.why strong { color: var(--ink); font-weight: 500; }
.btn { font: 500 .95rem var(--body); border-radius: 999px; padding: .6rem 1.2rem; cursor: pointer; border: 1px solid var(--ink); background: transparent; color: var(--ink); justify-self: start; }
.btn.primary { background: var(--scarlet); border-color: var(--scarlet); color: var(--on-accent); }
.done { border: 1px solid var(--rule); border-radius: 16px; background: var(--card); padding: 1.6rem; display: grid; gap: .8rem; }
.done h2 { font-family: var(--display); font-weight: 300; font-size: 2rem; margin: 0; }
.done p { margin: 0; color: var(--soft); }
.bp-foot { border-top: 1px solid var(--rule); padding-block: 1.3rem 2.5rem; font-size: .82rem; color: var(--muted); }
.bp-foot p { margin: 0; max-width: 70ch; }
.bp-top nav { display: flex; align-items: center; gap: 1rem; font-size: .9rem; color: var(--soft); }