:root{--gold:#ffc400;--ink:#111;--gray:#f5f5f5;--white:#fff;--line:#deded9;color:var(--ink);font-family:"Inter","Segoe UI",sans-serif;line-height:1.55}
*{box-sizing:border-box}body{margin:0}img{display:block;max-width:100%}button,a,input,summary{-webkit-tap-highlight-color:transparent}a{color:inherit;text-decoration:none}button,summary{cursor:pointer}button{font:inherit}a:focus-visible,button:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid #ac6700;outline-offset:4px}p{margin:0 0 1rem}h1,h2,h3{margin:0 0 1rem;line-height:1.07;letter-spacing:-.04em;text-wrap:balance}h2{font-size:clamp(2rem,4.4vw,3.5rem)}h3{font-size:1.45rem}ul{margin:0;padding:0;list-style:none}.wrap{width:min(1140px,calc(100% - 48px));margin:auto}.section{padding-block:clamp(3rem,8vw,6.5rem)}.split{display:grid;grid-template-columns:1fr 1fr;gap:clamp(2rem,6vw,5rem);align-items:center}.muted{background:var(--gray)}
header{background:var(--ink);color:white;border-bottom:1px solid #333}nav,footer .wrap{min-height:72px;display:flex;align-items:center;justify-content:space-between;gap:16px}nav>div{display:flex;gap:27px;font-size:.88rem;color:#ddd}.brand{font-weight:800;letter-spacing:-.045em;white-space:nowrap}.brand b{display:inline-grid;place-items:center;background:var(--gold);color:var(--ink);width:29px;height:29px;border-radius:6px;margin-right:.35rem}.brand span{color:var(--gold)}.navcta{border:1px solid #676767;border-radius:6px;padding:.55rem .9rem;font-weight:700;font-size:.8rem;white-space:nowrap}
.hero{background:var(--ink);color:white;overflow:hidden}.hero .wrap{min-height:630px;padding-block:65px;grid-template-columns:1.13fr .87fr}.tag{font-size:.75rem;font-weight:850;letter-spacing:.15em;margin-bottom:1rem}.hero .tag,.offer .tag{color:var(--gold)}h1{font-size:clamp(2.55rem,5.9vw,5.25rem);font-weight:900;letter-spacing:-.065em}em{color:var(--gold);font-style:normal}.intro{font-size:1.08rem;color:#ddd;max-width:52ch}.button{display:inline-flex;align-items:center;justify-content:center;gap:.55rem;padding:1rem 1.2rem;background:var(--gold);color:var(--ink);border:0;border-radius:7px;font-weight:850;line-height:1.3;text-align:center}.button:hover{background:#ffda57}.note{color:#ccc;font-size:.82rem;margin:1rem 0 0}.note span{margin-inline:.3rem}.stage{isolation:isolate;position:relative;display:grid;place-items:center;min-height:440px;perspective:1000px}.stage:before{content:"";position:absolute;inset:3%;z-index:-1;background:radial-gradient(ellipse,#ffc4003d,transparent 68%)}.stage:after{content:"";position:absolute;inset:4% 2%;z-index:-2;border:1px solid #ffc40030;border-radius:50%;transform:rotate(-22deg)}.symbol{position:absolute;color:#ffc400a8;font:700 1.35rem monospace}.first{top:12%;left:4%}.second{bottom:7%;right:0}.book{width:min(65%,300px);position:relative;transform:rotateY(-18deg) rotateZ(-7deg);box-shadow:0 24px 42px #000c;border-radius:4px 1px 1px 4px}.book img{width:100%;border-radius:inherit}.book:after{content:"";position:absolute;left:100%;top:2px;bottom:3px;width:16px;background:repeating-linear-gradient(90deg,#b6b1a3 0 1px,#e8e4d8 1px 3px);transform:skewY(-16deg);transform-origin:left top}.ribbon{background:var(--gold);font-weight:800;text-align:center;padding:.8rem 0}.checklist li{display:flex;gap:.75rem;padding:.68rem 0;border-bottom:1px solid var(--line)}.checklist li:before{content:"✓";font-weight:900;color:#795900}.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem;margin-top:2rem}.cards article,.quiz{padding:clamp(1.2rem,3vw,2rem);background:white;border:1px solid var(--line);border-radius:12px}.cards .tag{margin-top:1.2rem}.cards p:last-child,.teacher p:last-child{margin-bottom:0}.math{display:inline-block;background:var(--gold);border-radius:7px;padding:.38rem .65rem;font:700 1.15rem monospace}
fieldset{margin:0 0 1rem;padding:0;border:0;min-width:0}legend{font-size:1.25rem;font-weight:800;line-height:1.25;padding:0}.source{font-size:.78rem;color:#555;margin:.5rem 0 1rem}.quiz label{display:flex;align-items:center;gap:.55rem;border:1px solid var(--line);padding:.65rem;margin:.45rem 0;border-radius:6px;cursor:pointer}.quiz label:has(:checked){border-color:#a67700;background:#fff7d7}.quiz input{accent-color:#795900}.feedback:not(:empty){margin:1rem 0 0;background:#fff3bf;padding:.8rem;border-radius:6px}.preview{background:#fff3bf}.controls{display:flex;gap:1rem;align-items:center;margin-top:1.25rem}.controls button{background:white;border:1px solid #111;border-radius:6px;min-width:45px;min-height:45px}.paper{perspective:950px;display:grid;place-items:center}.paper img{width:min(calc(100% - 12px), 350px);height:auto;box-shadow:10px 10px 0 #111,0 14px 40px #0002}.teacher{display:grid;grid-template-columns:auto 1fr;align-items:center;gap:clamp(1.5rem,5vw,4rem)}.portrait{width:clamp(90px,18vw,200px);aspect-ratio:1;display:grid;place-items:center;background:var(--gold);border-radius:14px;font-size:clamp(2.4rem,7vw,5.5rem);font-weight:900;letter-spacing:-.07em}.offer{display:grid;grid-template-columns:1.2fr .8fr;gap:2rem;border-radius:16px;background:var(--ink);color:white;padding:clamp(1.5rem,6vw,4rem);align-items:center}.offer p:last-child{margin-bottom:0;color:#ddd}.price{display:block;font-size:clamp(2.6rem,6vw,4.5rem);line-height:1.1;margin-bottom:.25rem;letter-spacing:-.065em}.offer button{width:100%}#checkout{font-size:.86rem;margin-top:.7rem}.faq{max-width:820px}.faq h2{margin-bottom:1.5rem}details{border-bottom:1px solid var(--line)}summary{padding:1rem .1rem;font-weight:750}details p{padding:0 .1rem;color:#444}footer{background:var(--ink);color:white;font-size:.85rem}
@media(max-width:740px){.wrap{width:calc(100% - 32px)}nav>div{display:none}.split,.hero .wrap,.cards,.offer{grid-template-columns:1fr}.hero .wrap{min-height:auto;padding-block:3rem 2rem;gap:1rem}.stage{min-height:340px}.book{width:min(60%,230px)}.hero .button{width:100%}.teacher{grid-template-columns:1fr}.cards{margin-top:1.3rem}footer .wrap{align-items:flex-start;justify-content:center;flex-direction:column;padding-block:1.2rem;gap:.3rem}}
.skip{position:absolute;top:8px;left:8px;z-index:10;background:var(--gold);padding:.7rem 1rem;transform:translateY(-150%)}.skip:focus{transform:none}
.bundle{display:table;padding:.4rem .65rem;border:1px solid #ffc40070;border-radius:5px;color:var(--gold);font-size:.77rem;font-weight:850;letter-spacing:.09em}.purchase [data-price]{white-space:nowrap}.stage .book{position:absolute;right:4%;bottom:4%;width:36%;max-width:175px;z-index:2}.stage .book img{height:auto}.laptop{width:89%;margin-right:7%;margin-bottom:8%;position:relative;transform:rotateY(9deg) rotateZ(-4deg)}.screen{display:grid;align-content:center;gap:.55rem;aspect-ratio:16/10;padding:8%;border:8px solid #414141;border-radius:13px 13px 5px 5px;background:linear-gradient(135deg,#2b281c,#111 70%);box-shadow:0 18px 30px #0008}.screen small{font-weight:800;letter-spacing:.13em;color:var(--gold);font-size:clamp(.55rem,1.3vw,.78rem)}.screen strong{font-size:clamp(1.6rem,4vw,3rem);line-height:.95;letter-spacing:-.055em}.screen-logic{color:var(--gold);font:700 clamp(.72rem,1.8vw,1.13rem) monospace}.screen-logic span{margin-inline:.25rem}.laptop:after{content:"";position:absolute;top:100%;left:-6%;width:112%;height:12px;border-radius:2px 2px 50% 50%;background:linear-gradient(#e0e0e0,#575757)}
.quiz-stack{display:grid;gap:1rem}.quiz label.right{background:#e7f4eb;border-color:#377648}.quiz label.wrong{background:#fff0ea;border-color:#a54631}.quiz .feedback:empty{margin:0}.portrait{object-fit:cover;height:auto}.video-frame{aspect-ratio:16/9;background:#111;color:#fff;border-radius:12px;display:grid;place-content:center;justify-items:center;gap:.7rem;overflow:hidden}.video-frame span:first-child{color:#ffc400;font-size:2rem}.video-frame:has(video){display:block}.video-frame video{display:block;width:100%;height:100%}.offer .purchase{width:100%}.offer-items li{padding-block:.25rem}.offer-items li::before{content:"✓";color:var(--gold);margin-right:.6rem}.paper img{border-radius:3px}
@media(max-width:740px){.stage{min-height:clamp(245px,75vw,365px)}.stage .book{right:8%;bottom:6%}.hero .button{flex-wrap:wrap}.portrait{width:min(48vw,180px)}}

.payment-term{display:block;margin-bottom:1rem;color:#ddd}