:root{--ink:#233f38;--muted:#708077;--paper:#f6f7ef;--green:#26785b;--line:#dce3d7;--water:#bce4e8}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Hiragino Kaku Gothic ProN","Yu Gothic",sans-serif;font-size:14px;line-height:1.7}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;color:inherit;cursor:pointer}button:disabled{cursor:default}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #dd9b26;outline-offset:5px}a{color:inherit;text-decoration:none}[hidden]{display:none!important}.site-header{max-width:1200px;margin:auto;padding:28px 36px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;font-size:18px;font-weight:800;line-height:1.4}.brand small{display:block;font-size:9px;letter-spacing:1.7px;margin-top:4px}.brand-mark{background:var(--green);color:white;border-radius:13px;width:42px;height:42px;text-align:center;font-size:35px;line-height:35px}.header-note{font-size:12px;color:var(--muted)}main{max-width:1200px;margin:auto;padding:0 36px}.hero{display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:38px;padding:60px 0 66px}.eyebrow{font-size:10px;font-weight:800;letter-spacing:2.3px;color:var(--green);margin:0 0 15px}.hero h1{font-size:clamp(32px,3.6vw,47px);letter-spacing:.015em;line-height:1.55;margin:0 0 21px;font-weight:800}.hero h1 span{color:var(--green)}.intro{font-size:14px;line-height:2;color:#63766b;margin-bottom:26px}.primary{border:0;border-radius:10px;background:var(--green);color:#fff;padding:14px 25px;font-weight:700;display:inline-flex;justify-content:center;align-items:center;gap:34px;box-shadow:0 4px 0 #1a5d4520;min-height:48px}.primary:hover:not(:disabled){background:#1b6249}.primary:disabled{opacity:.55}.hero-tags{display:flex;gap:19px;margin-top:24px;color:#7c887e;font-size:10px}.hero-art{height:345px;position:relative;overflow:hidden;border-radius:47% 45% 43% 39%;background:#e6efdc;isolation:isolate}.art-river{position:absolute;background:#acdce0;left:30%;width:43%;height:130%;top:-15%;transform:rotate(17deg);border-left:9px solid #d1e6d7;border-right:9px solid #d1e6d7}.art-island{position:absolute;z-index:1;display:grid;text-align:center;gap:10px;font-size:34px;top:83px}.art-island>span:first-child{font-size:67px}.left-island{left:7%;transform:rotate(-5deg)}.right-island{right:5%}.art-boat{position:absolute;left:39%;top:47%;z-index:3;transform:rotate(-7deg);font-size:33px;white-space:nowrap}.art-boat div{height:25px;background:#bc7d43;border-radius:6px 6px 45px 45px;border-top:7px solid #e5b971;box-shadow:0 8px 0 #559da52b}.art-cloud{position:absolute;font-size:56px;color:#fff;opacity:.8;z-index:2}.cloud-one{top:12px;left:15%}.cloud-two{right:17%;top:28px;font-size:38px}.art-caption{position:absolute;bottom:30px;left:50%;transform:translateX(-50%) rotate(-4deg);background:#fffaf0;border-radius:8px;padding:9px 16px;font-size:11px;white-space:nowrap;box-shadow:0 3px 8px #233f380a}.ripple{position:absolute;color:#f3ffff;font-size:50px}.r1{top:55px;left:51%}.r2{bottom:54px;left:28%}.section-heading{display:flex;align-items:center;justify-content:space-between;margin-bottom:25px}.section-heading h2{font-size:23px;margin:0}.section-heading .eyebrow{margin-bottom:7px}.section-heading>span{font-size:11px;color:var(--muted)}.level-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.level-card{text-align:left;border:1px solid var(--line);border-radius:15px;background:#fffefa;padding:22px;transition:transform .18s,box-shadow .18s}.level-card:hover{transform:translateY(-4px);box-shadow:0 8px 25px #2343380d;border-color:#97b9a1}.card-top{display:flex;justify-content:space-between;align-items:center;gap:8px}.level-number{font-size:10px;font-weight:800;letter-spacing:1.7px}.stars{color:#bc8b37;font-size:13px;letter-spacing:2px}.card-icons{font-size:35px;letter-spacing:8px;margin:22px 0 15px;height:60px;background:#f0f3e7;border-radius:10px;text-align:center;line-height:60px}.card-1 .card-icons{background:#eaf2e9}.card-2 .card-icons{background:#f6eee1}.card-3 .card-icons{background:#eaf0f3}.card-4 .card-icons{background:#f2ebdf}.level-card h3{font-size:18px;margin:0 0 6px}.level-card>p{font-size:11px;color:var(--muted);margin:0;min-height:38px}.card-bottom{border-top:1px solid #e8ece3;margin-top:16px;padding-top:13px;display:flex;align-items:center;justify-content:space-between;font-size:10px;color:var(--green);font-weight:600}.card-bottom b{font-size:19px}.how-to{margin:42px 0 55px;padding:25px 28px;background:#ebeee3;border-radius:13px}.how-to h2{font-size:15px;margin:0 0 15px}.how-to>div{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.how-to p{display:flex;align-items:center;gap:13px;margin:0;font-size:11px;color:var(--muted)}.how-to b{font-size:23px;color:#8ea18d;font-weight:500}.how-to strong{display:block;color:var(--ink);font-size:12px;margin-bottom:3px}footer{max-width:1128px;margin:0 auto;padding:23px 0;border-top:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;color:#829082;font-size:10px}footer>span{letter-spacing:1.3px;font-weight:700}footer p{margin:0}.game-top{display:flex;justify-content:space-between;align-items:center;margin-top:28px}.text-button{background:none;border:0;padding:10px 0;color:var(--green)}.game-heading{display:flex;justify-content:space-between;align-items:center;margin-top:20px}.game-heading h1{font-size:29px;margin:0}.game-heading .eyebrow{margin-bottom:4px}.move-counter{background:white;border:1px solid var(--line);border-radius:13px;padding:8px 24px;display:flex;gap:10px;align-items:baseline}.move-counter strong{font-size:32px}.game-instruction{color:var(--muted);font-size:12px;margin:20px 0}.board{height:420px;position:relative;border-radius:22px;overflow:hidden;background:var(--water);border:1px solid #a8c9b7}.river-pattern{position:absolute;inset:0;background:repeating-linear-gradient(173deg,transparent 0px,transparent 38px,#ffffff38 40px,transparent 43px,transparent 75px)}.bank{position:absolute;top:0;bottom:0;width:36%;padding:19px;background:#e3edcc;z-index:1}.left-bank{left:0;border-right:9px solid #ccdeb6;border-radius:0 45% 35% 0 / 0 12% 20% 0}.right-bank{right:0;border-left:9px solid #ccdeb6;border-radius:45% 0 0 35% / 12% 0 0 20%}.bank h2{font-size:16px;margin:0 0 18px;display:flex;gap:10px;align-items:center}.bank h2 span{font-size:9px;letter-spacing:1.4px;color:#83987a}.characters{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px;align-content:start}.character{background:#fffef8;border:2px solid #fffef8;border-radius:12px;min-height:75px;min-width:0;padding:7px 3px;position:relative;box-shadow:0 3px 0 #48654517;transition:transform .15s,border-color .15s}.character:not(:disabled):hover{transform:translateY(-3px);border-color:#479776}.character:disabled{opacity:.63}.emoji{display:block;font-size:29px;line-height:1.25}.character-name{display:block;font-size:10px;font-weight:700;white-space:nowrap}.character i{position:absolute;top:-5px;right:-3px;font:700 9px sans-serif;border-radius:50%;background:#dfae56;color:#422d14;width:17px;height:17px;line-height:17px}.group-A{border-color:#e7bc6b}.group-B{border-color:#8dbcd3}.group-C{border-color:#c39ecd}.group-B i{background:#8dbcd3}.group-C i{background:#c39ecd}.group-missionary{border-bottom-color:#8dbcd3}.group-cannibal{border-bottom-color:#e7bc6b}.empty-bank{grid-column:1/-1;font-size:11px;color:#829274;margin-top:20px}.boat{position:absolute;z-index:2;width:155px;left:calc(36% - 48px);bottom:47px;transition:left .65s ease-in-out;filter:drop-shadow(0 8px 0 #3d839017)}.boat[data-side="1"]{left:calc(64% - 107px)}.boat.no-motion{transition:none}.passengers{display:flex;gap:6px;padding:0 8px;align-items:end;height:80px}.passengers .character{width:66px;min-height:68px;border-color:#eecb84}.empty-seat{border:2px dashed #f1ffff99;border-radius:10px;width:66px;height:60px;text-align:center;line-height:56px;color:#fff;font-size:24px}.boat-hull{height:31px;background:#b77c43;border-radius:5px 5px 55px 55px;border-top:7px solid #dfb376;text-align:center;color:#fff6e8;font-size:10px;line-height:19px}.boat-location{display:block;position:absolute;top:118px;width:100%;text-align:center;font-size:10px;font-weight:600;color:#416f74}.play-controls{display:flex;justify-content:center;gap:14px;margin-top:22px}.secondary{background:transparent;border:1px solid #bcc9b7;border-radius:10px;padding:10px 20px;min-height:48px}.message{min-height:48px;margin:15px 0;text-align:center;padding:11px 16px;background:#e9f0e4;border-radius:10px;font-size:13px}.message.error{background:#fff0df;color:#925021}.rules{border:1px solid var(--line);border-radius:12px;padding:18px 23px;margin:23px 0 42px;background:#fffefa}.rules summary{cursor:pointer;font-weight:700}.rules ul{padding-left:22px;line-height:2.1;font-size:13px}.rule-note{font-size:11px;color:var(--muted);border-top:1px solid var(--line);padding-top:12px}.success{text-align:center;background:#e5eedb;border:1px solid #bccfab;border-radius:18px;padding:25px;margin:22px 0}.success h2{margin:4px 0}.success p{font-size:13px}.success-icon{font-size:38px}@media(min-width:1000px){.card-3,.card-4{grid-column:auto}.level-grid{grid-template-columns:repeat(6,1fr)}.level-card{grid-column:span 2}.card-3,.card-4{grid-column:span 3}.card-3 .card-icons,.card-4 .card-icons{letter-spacing:20px}}@media(max-width:760px){.site-header{padding:20px 22px}main{padding:0 22px}.hero{gap:16px;padding:38px 0 44px}.hero h1{font-size:30px}.hero-art{height:280px}.art-island{font-size:25px}.art-island>span:first-child{font-size:47px}.art-boat{font-size:24px;left:34%}.hero-tags{flex-direction:column;gap:3px}.level-grid{grid-template-columns:repeat(2,1fr)}.section-heading>span{display:none}.bank{padding:16px 12px;width:35%}.characters{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.board{height:490px}.boat{width:136px;left:calc(35% - 43px);bottom:36px}.boat[data-side="1"]{left:calc(65% - 93px)}.passengers{gap:4px;padding:0 4px}.bank h2{gap:5px}.how-to>div{gap:12px}.how-to p{align-items:start}footer{margin:0 22px}.character-name{font-size:10px}}
@media(max-width:520px){.header-note{display:none}.brand{font-size:16px}.hero{grid-template-columns:1fr;padding-top:30px;gap:26px}.hero h1{font-size:36px}.hero-copy{position:relative}.intro{font-size:13px}.hero-tags{flex-direction:row;gap:15px;font-size:9px}.hero-art{height:240px;border-radius:24px}.art-island{top:35px;font-size:29px}.art-island>span:first-child{font-size:53px}.art-boat{font-size:30px;top:43%;left:40%}.art-caption{bottom:15px}.section-heading h2{font-size:21px}.level-grid{gap:12px}.level-card{padding:15px 12px}.card-top{flex-wrap:wrap;gap:4px}.level-number{font-size:9px}.stars{font-size:11px;letter-spacing:1px}.card-icons{font-size:25px;letter-spacing:1px;margin:16px 0 12px}.level-card h3{font-size:14px}.level-card>p{font-size:10px;min-height:51px}.card-bottom{font-size:9px}.card-4{grid-column:1/-1}.card-4>p{min-height:0}.how-to{padding:22px}.how-to>div{grid-template-columns:1fr;gap:18px}.how-to p{gap:18px}.game-heading h1{font-size:23px}.move-counter{padding:5px 14px}.move-counter strong{font-size:28px}.game-instruction{font-size:11px}.board{height:520px;margin:0 -10px;border-radius:16px}.bank{width:36%;padding:13px 7px;border-width:5px}.bank h2{font-size:13px;display:block;margin-bottom:15px}.bank h2 span{display:block;font-size:8px}.characters{gap:6px}.character{border-radius:9px;min-height:72px;padding:8px 0}.emoji{font-size:25px}.character-name{font-size:9px;letter-spacing:-.4px}.boat{width:126px;bottom:33px;left:calc(36% - 52px)}.boat[data-side="1"]{left:calc(64% - 74px)}.passengers .character{width:58px}.empty-seat{width:58px}.empty-bank{font-size:10px}.rules{padding:15px}.rules ul{font-size:12px}.message{font-size:12px}.play-controls{gap:10px}.play-controls .primary{gap:20px}footer{display:block;text-align:center;font-size:9px}footer p{margin-top:7px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}
.character-name{white-space:normal;overflow-wrap:anywhere}
/* Mode selection and warnings overlay the board without shifting its layout. */
.mode-badge{font-size:11px;color:var(--green);background:#e5eddc;border-radius:20px;padding:4px 10px;margin-left:auto;margin-right:15px;white-space:nowrap}.game-dialog{border:1px solid var(--line);border-radius:22px;background:var(--paper);color:var(--ink);width:min(460px,calc(100% - 32px));max-height:calc(100dvh - 32px);overflow:auto;padding:30px;text-align:center;box-shadow:0 20px 80px #18372c40}.game-dialog::backdrop{background:#16362e99}.game-dialog h2{font-size:25px;margin:0 0 12px}.mode-options{display:grid;gap:12px;margin:20px 0}.mode-option{border:2px solid #c8d8bc;border-radius:13px;background:#fffefa;text-align:left;padding:17px;min-height:80px}.mode-option:hover{border-color:var(--green);background:#edf3e6}.mode-option strong{display:block;font-size:18px;margin-bottom:6px}.mode-option span{display:block;font-size:13px;line-height:1.8}.dialog-note{font-size:12px;color:#63766b;line-height:1.8}.warning-dialog{border:3px solid #d9a253;background:#fffaf0}.warning-icon{font-size:48px;line-height:1.3;color:#a96316}.warning-dialog h2{font-size:24px;margin-top:12px}.warning-dialog #error-reason{font-size:20px;line-height:1.8;font-weight:700;margin:20px 0 26px;overflow-wrap:anywhere}.game-over h2{font-size:36px;letter-spacing:2px;color:#9e4533}.dialog-actions{display:grid;gap:12px}.game-dialog button{max-width:100%}@media(max-width:520px){.game-dialog{padding:24px 18px}.game-top{flex-wrap:wrap;gap:6px}.mode-badge{font-size:10px;margin-right:5px}.warning-dialog #error-reason{font-size:19px}.game-over h2{font-size:30px}}