*,*:before,*:after{box-sizing:border-box}html,body{margin:0;width:100%;height:100%}body{font-family:Hiragino Sans,Noto Sans JP,Segoe UI,sans-serif;background:linear-gradient(180deg,#d9f0ff,#f7fcff);color:#10324d}#app{min-height:100%;display:grid;place-items:center;padding:16px}.home,.game{width:min(460px,100%);background:#fff;border-radius:24px;padding:20px 16px 24px;box-shadow:0 14px 30px #13446826}h1{margin:0;text-align:center;font-size:2.1rem;color:#005b91}.subtitle{margin:10px 0 22px;text-align:center;font-size:1.15rem;color:#2a6288}.difficulty-buttons{display:grid;gap:14px}.level-btn{display:flex;flex-direction:column;align-items:flex-start;justify-content:center;padding:10px 16px}.level-meta{font-size:.95rem;color:#2a6288}.main-btn,.small-btn,.tile{border:none;border-radius:16px;font-weight:700;cursor:pointer}.main-btn{min-height:64px;font-size:1.35rem;background:#ffe37a;color:#0f3b5d}.main-btn:active,.small-btn:active,.tile:active{transform:scale(.98)}.topbar{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:8px}.small-btn{min-height:44px;padding:0 12px;background:#c8ecff;color:#0f446c;font-size:1rem}.moves{margin:0;text-align:center;font-size:.95rem;color:#2d688f}.board-wrap{margin-top:16px}.board{display:grid;gap:8px}.board.size-3{grid-template-columns:repeat(3,1fr)}.board.size-4{grid-template-columns:repeat(4,1fr)}.board.size-5{grid-template-columns:repeat(5,1fr)}.tile{aspect-ratio:1 / 1;font-size:clamp(1.3rem,6vw,2rem);background:#fff4b5;color:#10476f;box-shadow:inset 0 -3px #00000014}.tile-blank{background:#e8f6ff;box-shadow:inset 0 0 0 2px #ccecff}.board.size-5 .tile{font-size:clamp(1rem,4.6vw,1.55rem)}.goal-card{margin-top:12px;padding:10px;background:#eef9ff;border-radius:14px}.goal-title{margin:0 0 8px;font-size:.95rem;color:#1f567f}.goal-grid{display:grid;gap:4px}.goal-grid.size-3{grid-template-columns:repeat(3,1fr)}.goal-grid.size-4{grid-template-columns:repeat(4,1fr)}.goal-grid.size-5{grid-template-columns:repeat(5,1fr)}.goal-cell{aspect-ratio:1 / 1;border-radius:8px;display:grid;place-items:center;font-size:clamp(.62rem,2.8vw,.86rem);font-weight:700;background:#fff0a8;color:#16496f}.goal-blank{background:#dff1ff}.clear-card{margin-top:16px;background:#e7fbe6;border-radius:18px;padding:14px 12px;text-align:center}.clear-title{margin:0;font-size:1.55rem;color:#1d7a22}.clear-subtitle{margin:4px 0 14px;font-size:1rem;color:#257f2b}