.k28-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,260px),1fr));gap:16px;margin:20px 0}.k28-card{border:1px solid var(--line,#d6ddd5);border-radius:16px;padding:20px;min-width:0}.k28-character{display:inline-flex;flex-direction:column;align-items:center;gap:0}.k28-character small{font-size:1rem;font-weight:700}.k28-character>b{font-size:3rem;line-height:1.25}.k28-example{display:flex;flex-direction:column;align-items:flex-start;gap:6px;padding:12px 0;border-top:1px solid var(--line,#d6ddd5)}.k28-word{display:inline-flex;align-items:flex-end;gap:3px}.k28-word>span{display:flex;flex-direction:column;align-items:center}.k28-word small{font-size:.875rem;min-height:1.3em}.k28-word b{font-size:1.7rem;font-weight:500;line-height:1.25}.k28-reading{font-size:1rem}.k28-board{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin:20px 0}.k28-board h3{font-size:1rem}.k28-tile{display:flex;align-items:center;justify-content:center;gap:5px;width:100%;min-height:96px;margin:10px 0;padding:10px;border:2px solid #96aaa4;background:#fff;color:#173d37;border-radius:12px;font-size:1rem;overflow-wrap:anywhere}.k28-tile [lang=ja]{font-size:2rem}.k28-tile.selected{border-color:#176b57;background:#d8f2e8;box-shadow:0 0 0 2px #176b57}.k28-tile.done{background:#e2ebe6;border-style:dashed;color:#41645a;opacity:.72}.k28-tile:focus-visible{outline:3px solid #ca8d24;outline-offset:3px}.k28-tip-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,240px),1fr));gap:18px}.k28-tip-grid>div{padding:16px;background:#eff5f2;border-radius:12px;color:#173d37}.k28-tips ruby{font-size:1.4rem}.k28-tips rt{font-size:.875rem}@media(max-width:520px){.k28-board{gap:7px}.k28-tile{padding:6px;min-height:114px;font-size:.875rem}.k28-board h3{font-size:.875rem}.k28-card{padding:16px}}