:root{color-scheme:light;--background:#f7f9f5;--foreground:#304943;--primary:#387d68;--border:#dce5dc;--card:#fffefa}
*{box-sizing:border-box}body{margin:0;background:var(--background);color:var(--foreground);font-family:'Segoe UI',Arial,sans-serif}a{color:inherit;text-decoration:none}button{font:inherit;cursor:pointer}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #387d68;outline-offset:5px}.site-header{background:#fffefa;border-bottom:1px solid var(--border)}.header-inner{max-width:1320px;min-height:88px;margin:auto;padding:15px 36px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:13px}.brand-icon{display:grid;place-items:center;width:46px;height:46px;border-radius:15px;background:#e7f0df;color:#48775b;font-size:28px;font-weight:800}.brand strong{display:block;font-size:23px;letter-spacing:-.7px}.brand small{display:block;color:#768779;font-size:11px;margin-top:4px}.header-note{color:#7d8c7b;font-size:13px}.portal{max-width:1320px;margin:auto;padding:30px 36px 24px}.welcome{display:flex;justify-content:space-between;align-items:center;gap:24px}.eyebrow{font-weight:750;font-size:10px;letter-spacing:1.8px;color:#789572}.welcome h1{font-size:34px;letter-spacing:-1px;margin:8px 0 10px;line-height:1.3}.welcome p{font-size:14px;color:#758570;margin:0;line-height:1.65}.stamp{border:1px solid #e8dfc0;background:#fff6da;border-radius:30px;color:#8e7849;padding:13px 17px;font-size:12px;white-space:nowrap}.grade-switch{display:flex;gap:12px;margin:26px 0 27px}.grade-link{display:flex;align-items:center;gap:15px;border:1px solid var(--border);border-radius:15px;padding:15px 20px;min-width:230px;background:#fffefa;color:#667e6d}.grade-link:hover{border-color:#8aac8a}.grade-link[aria-current=page]{background:var(--primary);color:white;border-color:var(--primary);box-shadow:0 4px 0 #e0e9dd}.grade-number{display:grid;place-items:center;border-radius:10px;background:#edf3e8;width:41px;height:41px;font-size:26px;font-weight:800;color:#678a6f}.grade-link[aria-current=page] .grade-number{background:#ffffff26;color:white}.grade-info b,.grade-info small{display:block}.grade-info b{font-size:18px}.grade-info small{font-size:11px;margin-top:3px;opacity:.85}.grade-arrow{margin-left:auto;font-size:20px}.section-heading{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:17px}.section-heading h2{font-size:21px;font-weight:750;letter-spacing:-.4px;margin:0}.section-heading>span{color:#758775;font-size:13px}.lesson-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:17px}.lesson-card{border:1px solid var(--border);border-radius:18px;background:var(--card);overflow:hidden;min-width:0;display:flex;flex-direction:column}.lesson-open{min-height:300px;box-shadow:0 3px 0 #e7edde;transition:transform .18s,box-shadow .18s,border-color .18s}.lesson-open:hover{transform:translateY(-4px);box-shadow:0 10px 25px #3e645016;border-color:#92b59f}.lesson-top{padding:19px 20px 16px;display:flex;align-items:center;justify-content:space-between;gap:12px;background:var(--tint,#eef2e8)}.lesson-number{font-size:32px;line-height:1.1;letter-spacing:-.8px;font-weight:850;color:var(--ink,#627b61)}.lesson-icon{font-size:28px;line-height:1;display:grid;place-items:center;width:43px;height:43px;background:#ffffff70;border-radius:13px}.lesson-body{padding:18px 20px;display:flex;flex-direction:column;flex:1}.lesson-title{font-size:20px;font-weight:750;line-height:1.42;letter-spacing:-.35px;margin:0 0 16px}.game-name{font-size:13px;color:#748772;line-height:1.6;margin:auto 0 15px}.play-row{display:flex;justify-content:space-between;align-items:center;font-size:13px;font-weight:750;color:#377c60;margin-top:auto}.play-arrow{font-size:21px;display:grid;place-items:center;width:29px;height:29px;border-radius:50%;background:#eaf3e5}.lesson-locked{background:#f1f4ed;border-color:#e0e6dc;min-height:211px}.lesson-locked .lesson-top{background:transparent;padding-bottom:8px}.lesson-locked .lesson-number{color:#83937e;font-size:30px}.lesson-locked .lesson-icon{font-size:17px;background:#e7eee0;width:31px;height:31px;opacity:.65}.lesson-locked .lesson-body{padding-top:10px}.lesson-locked .lesson-title{color:#778971;font-size:17px;font-weight:650}.locked-label{color:#84937d;font-size:11px;margin:auto 0 0;line-height:1.5}.variants{display:grid;gap:11px;margin:0 0 18px}.variant{font-size:15px;line-height:1.45;color:#75866d;margin:0}.variant b{color:#667d5d}.lock-note{text-align:center;font-size:12px;line-height:1.6;color:#819078;margin:24px 0}.portal-footer{border-top:1px solid #e0e7da;display:flex;justify-content:space-between;gap:16px;padding-top:20px;color:#809076;font-size:11px}.empty-note{padding:16px 20px;margin:0 0 20px;background:#eaf2e4;border:1px solid #dbe6d2;border-radius:14px;color:#66805a;line-height:1.6;font-size:14px}.help{margin-top:23px;color:#778a70;font-size:12px;line-height:1.7}.help summary{cursor:pointer;display:list-item}.help p{margin-bottom:0}.message-page{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:30px}.message-page h1{font-size:32px}.message-page a{padding:13px 20px;background:var(--primary);color:white;border-radius:12px}
@media(min-width:1600px){.portal,.header-inner{max-width:1470px}.lesson-open{min-height:310px}.lesson-number{font-size:36px}.lesson-title{font-size:23px}.lesson-locked .lesson-title{font-size:19px}.variant{font-size:17px}}
@media(max-width:1050px){.lesson-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.stamp{display:none}.lesson-open{min-height:270px}.lesson-locked{min-height:195px}.lesson-title{font-size:21px}.lesson-locked .lesson-title{font-size:18px}}
@media(max-width:570px){.header-inner{padding:15px 20px;min-height:78px}.brand strong{font-size:21px}.brand small{font-size:10px}.brand-icon{width:40px;height:42px}.header-note{display:none}.portal{padding:27px 20px 22px}.welcome h1{font-size:28px}.welcome p{font-size:13px}.grade-switch{gap:10px}.grade-link{min-width:0;flex:1;padding:13px;gap:10px}.grade-number{width:31px;height:35px;font-size:23px}.grade-info b{font-size:16px}.grade-info small{font-size:10px}.grade-arrow{display:none}.section-heading h2{font-size:19px}.section-heading>span{font-size:11px}.lesson-grid{gap:12px}.lesson-top{padding:16px 14px 13px}.lesson-number,.lesson-locked .lesson-number{font-size:29px}.lesson-icon{width:29px;height:33px;font-size:23px}.lesson-body{padding:15px 14px}.lesson-title{font-size:17px;line-height:1.45}.game-name{font-size:11px}.lesson-open{min-height:280px}.lesson-locked .lesson-title{font-size:15px}.lesson-locked .lesson-body{padding:10px 14px 15px}.lesson-locked .lesson-top{padding:16px 14px 8px}.lesson-locked .lesson-icon{width:25px;height:25px;font-size:14px}.variant{font-size:13px}.lesson-locked{min-height:188px}.play-row{font-size:12px}.portal-footer{flex-direction:column;gap:8px}.help{font-size:11px}.lock-note{font-size:11px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important}.lesson-open:hover{transform:none}}