:root{--navy:#0a213d;--navy2:#0d3152;--mid:#174f78;--gold:#eab867;--goldlight:#f9ddaa;--mint:#4ecac8;--paper:#f5f7fb;--ink:#152f4e;--muted:#60758c;--border:#e2e9f0;--shadow:0 12px 42px rgba(17,43,73,.08)}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:86px}
body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.85 'Segoe UI',Tahoma,Arial,sans-serif;-webkit-font-smoothing:antialiased}
a{color:inherit}button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--gold);outline-offset:3px}
.container{width:min(1140px,calc(100% - 42px));margin-inline:auto}
.skip-link{position:absolute;top:-80px;z-index:1000;background:white;padding:10px}.skip-link:focus{top:5px}
.announcement{background:#061a32;color:#d9e6f3;text-align:center;font-size:12px;padding:6px 10px;letter-spacing:.15px}.announcement-icon{color:var(--gold)}.announcement-sep{color:var(--mint);padding:0 10px}
.site-header{background:#0c2747;color:white;position:sticky;top:0;z-index:100;box-shadow:0 6px 24px #041b3020;border-bottom:1px solid #ffffff17}.nav-wrap{min-height:80px;display:flex;align-items:center;justify-content:space-between;gap:18px}.brand{text-decoration:none;display:inline-flex;align-items:center;gap:12px;white-space:nowrap}.brand-logo{height:49px;width:49px;border:1px solid #ffffff45;background:linear-gradient(145deg,#173f65,#0b2749);color:#f6cc83;display:flex;align-items:center;justify-content:center;border-radius:15px;font-size:27px;font-weight:900;letter-spacing:-5px;box-shadow:inset 0 0 15px #ffffff08;padding-left:4px}.brand-logo span{font-size:20px;color:var(--mint);transform:translateY(2px)}.brand-words{display:flex;flex-direction:column;line-height:1.2;direction:ltr}.brand-words strong{font-size:21px;letter-spacing:-.4px}.brand-words small{color:#eac47e;font-size:9px;font-weight:800;letter-spacing:4.5px;margin-top:3px}.nav-links{display:flex;gap:31px;align-items:center}.nav-links a{text-decoration:none;color:#d7e5f1;font-weight:600;font-size:14px;transition:color .2s}.nav-links a:hover{color:var(--gold)}.nav-play{border-radius:100px;text-decoration:none;border:1px solid #eab86788;color:var(--goldlight);padding:10px 17px;display:inline-block;font-size:13px;font-weight:700}.nav-play:hover{background:#eab8671b}.nav-play span{margin-inline-start:5px}.menu-btn{display:none;background:transparent;border:1px solid #ffffff4a;color:white;border-radius:10px;font-size:21px;width:42px;height:42px;line-height:1}.mobile-nav{padding:8px 24px 20px;border-top:1px solid #ffffff1d}.mobile-nav a{display:block;color:white;text-decoration:none;padding:8px 4px}.mobile-nav[hidden]{display:none}
.hero{background:radial-gradient(ellipse at 7% 80%,#164e713e,transparent 40%),linear-gradient(123deg,#0b2848 0%,#0c3151 58%,#103755 100%);position:relative;overflow:hidden;color:white;padding:100px 0 104px}.hero:before{content:'';position:absolute;inset:0;background-image:radial-gradient(#acc9e1 1px,transparent 1px);background-size:38px 38px;opacity:.065;pointer-events:none}.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;align-items:center;gap:48px;position:relative}.eyebrow,.section-label{font-size:13px;color:#bc873e;font-weight:800;letter-spacing:.2px}.eyebrow{display:inline-flex;align-items:center;gap:10px;background:#ffffff0e;color:var(--goldlight);padding:6px 15px;border:1px solid #ffffff18;border-radius:100px}.live-dot{width:7px;height:7px;border-radius:100px;background:#65d1bf;box-shadow:0 0 0 4px #65d1bf1f}.hero h1{font-size:clamp(40px,5.05vw,70px);letter-spacing:-1.6px;line-height:1.34;margin:23px 0 18px;font-weight:900}.hero h1 span{color:var(--gold)}.hero-lead{color:#c4d7e7;line-height:2.05;font-size:16px;max-width:560px;margin:0 0 30px}.hero-lead b{color:#e6eff7}.hero-buttons{display:flex;gap:12px;flex-wrap:wrap}.btn{text-decoration:none;border:0;display:inline-flex;align-items:center;justify-content:center;gap:11px;padding:12px 24px;border-radius:11px;font-weight:800;white-space:nowrap;transition:transform .2s,background .2s,box-shadow .2s;line-height:1.5}.btn:hover{transform:translateY(-2px)}.btn-gold{color:#162b43;background:linear-gradient(95deg,#f1c77a,#eab05d);box-shadow:0 6px 20px #bd80373a}.btn-ghost{color:#f1f6fb;background:#ffffff10;border:1px solid #ffffff47}.btn-ghost:hover{background:#ffffff1e}.btn-primary{background:#184d76;color:white}.hero-proof{display:flex;align-items:center;gap:15px;color:#adc3d3;font-size:12px;margin-top:38px}.proof-avatars{direction:ltr;display:inline-flex;padding-right:8px}.proof-avatars i{font-style:normal;background:#1f526c;border:2px solid #0e2c49;border-radius:50%;width:34px;height:34px;display:grid;place-items:center;margin-right:-10px;color:#f3d49a;font-size:17px;font-weight:800}.proof-avatars i:nth-child(2){background:#26566c;color:#bbf3e4}.proof-avatars i:nth-child(3){background:#54637d;color:#fff}
.hero-visual{height:385px;position:relative;display:flex;align-items:center;justify-content:center;isolation:isolate}.orb{position:absolute;border-radius:50%;filter:blur(3px)}.orb-one{width:335px;height:335px;background:#2777a21b;border:1px solid #ffffff15;inset:8px 35px auto auto}.orb-two{width:220px;height:220px;border:1px solid #f1c27718;inset:95px auto auto 8px}.math-panel{position:relative;z-index:2;width:min(390px,90%);border-radius:22px;background:linear-gradient(145deg,#143b5f,#091f39);border:1px solid #ffffff3a;box-shadow:0 25px 65px #0414257a;transform:rotate(-3deg);overflow:hidden;padding:21px 21px 18px}.panel-top,.panel-bottom{display:flex;justify-content:space-between;align-items:center;direction:ltr}.panel-top span{display:flex;gap:6px}.panel-dot{display:block;width:7px;height:7px;background:#d8c0a4;border-radius:50%;opacity:.75}.panel-dot:nth-child(2){background:#6cc2c6}.panel-dot:nth-child(3){background:#f2c46d}.panel-top em,.panel-bottom{font-size:9px;letter-spacing:1.4px;font-style:normal;color:#91b4c9}.panel-formula{font:24px/1.5 Georgia,serif;direction:ltr;text-align:center;color:#f2d19a;margin-top:18px;white-space:nowrap}.graph{width:100%;height:180px}.panel-bottom{border-top:1px solid #ffffff18;padding-top:13px}.panel-bottom strong{color:#eac179}.float-card{position:absolute;z-index:3;background:#fff;box-shadow:0 18px 40px #06192d45;border-radius:14px;color:#15314d;padding:12px 16px;display:flex;align-items:center;gap:10px;white-space:nowrap}.float-card span{border-radius:10px;background:#edf8f5;display:grid;place-items:center;width:37px;height:37px;font-weight:bold;color:#229d89}.float-card strong{font-size:12px}.float-card small{display:block;color:#8a9caf;font-size:9px}.float-a{right:0;top:28px;transform:rotate(7deg)}.float-b{left:0;bottom:24px;transform:rotate(5deg)}
.trust-bar{background:#fff;border-bottom:1px solid var(--border)}.trust-grid{display:grid;grid-template-columns:repeat(4,1fr);padding:27px 0}.trust-grid>div{text-align:center;display:flex;flex-direction:column;gap:0;border-inline-start:1px solid var(--border)}.trust-grid>div:last-child{border:0}.trust-grid strong{font:900 30px/1.4 Arial,sans-serif;color:#163d63;direction:ltr}.trust-grid span{font-size:12px;color:var(--muted);font-weight:600}
.section{padding:82px 0}.section-intro{text-align:center;margin-bottom:35px}.section-intro h2,.library-heading h2,.app-banner h2{font-weight:900;font-size:clamp(26px,3vw,38px);line-height:1.55;margin:7px 0 8px;letter-spacing:-.7px}.section-intro p,.library-heading p{margin:0;color:#6b7e92}.benefits-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.benefit{background:white;border:1px solid #e7edf4;border-radius:20px;padding:32px 28px;box-shadow:0 3px 20px #14243e05}.benefit-icon{width:62px;height:62px;display:grid;place-items:center;font:900 29px Georgia,serif;border-radius:16px;margin-bottom:21px;direction:ltr}.icon-blue{background:#e4f2ff;color:#275b8e}.icon-gold{background:#fff3dd;color:#a97928}.icon-mint{background:#e1f7ee;color:#14866e}.benefit h3{margin:0 0 7px;font-size:20px}.benefit p{margin:0;color:var(--muted);font-size:14px;line-height:2}
.levels-section{background:#ecf1f7}.levels-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:17px}.level-card{position:relative;text-align:right;background:#fff;border:1px solid #e1e9f0;box-shadow:0 4px 16px #1c375a08;border-radius:17px;padding:23px 22px 28px;min-height:195px;overflow:hidden;display:flex;flex-direction:column;align-items:flex-start;transition:transform .2s,box-shadow .2s,border .2s}.level-card:hover{transform:translateY(-5px);box-shadow:0 13px 28px #173f621c;border-color:#c5d9ea}.level-number{font:900 34px/1.15 Arial,sans-serif;color:#cf9e51;direction:ltr;margin-bottom:23px}.level-name{font-size:17px;font-weight:800;color:#193b5c}.level-sub{color:#75899b;font-size:11px;direction:ltr}.level-arrow{position:absolute;left:19px;bottom:17px;color:#89a3ba;font-size:18px}
.library-section{background:#f7f9fc}.library-heading{display:flex;justify-content:space-between;gap:22px;align-items:center;margin-bottom:28px}.library-heading p{max-width:600px}.library-heading-badge{background:#eef6fc;border:1px solid #d8eaf6;border-radius:12px;color:#1a5780;padding:13px 19px;white-space:nowrap;font-size:17px;font-weight:800;display:flex;align-items:center;gap:10px}.library-heading-badge span{font-size:14px}.library-shell{background:white;border:1px solid #e4eaf0;padding:25px;border-radius:19px;box-shadow:var(--shadow)}.filter-search{position:relative}.filter-search span{position:absolute;right:18px;top:3px;font-size:36px;color:#8195a9;line-height:1.5;pointer-events:none}.filter-search input{display:block;width:100%;padding:15px 58px 15px 18px;border:1px solid #dbe4ec;background:#f8fafc;border-radius:12px;color:var(--ink);font-size:15px}.filter-search input::placeholder{color:#9caaba}.filter-row{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:17px}.filter-row label{display:flex;flex-direction:column;gap:6px;font-size:12px;color:#5a6e80;font-weight:700}.filter-row select{padding:10px 13px;border:1px solid #dbe4ec;background:#fdfefe;border-radius:10px;color:#203e5c;width:100%;font-size:14px}.filter-bottom{display:flex;justify-content:space-between;gap:15px;align-items:center;margin-top:22px;flex-wrap:wrap}.quick-filters{display:flex;gap:8px;flex-wrap:wrap}.chip{padding:7px 16px;border-radius:50px;border:1px solid #dce5ed;background:#fff;color:#64788b;font-size:13px;font-weight:800;transition:all .2s}.chip:hover{color:#143e65;border-color:#b6cbdc}.chip.active{background:#163f62;border-color:#163f62;color:#fff}.favorites-filter{background:#fff;border:1px solid #e1e8ef;border-radius:9px;padding:7px 13px;font-size:13px;font-weight:800;color:#536f87}.favorites-filter span{font-size:12px;background:#f0f3f7;border-radius:50px;padding:2px 7px;margin-inline-start:4px}.favorites-filter.is-active{background:#fff6ef;border-color:#eac69d;color:#a66c2b}.results-top{display:flex;justify-content:space-between;align-items:center;margin:28px 0 14px;gap:20px}.results-top p{font-size:14px;color:#516980;font-weight:700;margin:0}.reset-filter{border:0;background:transparent;color:#3c719b;font-size:13px;font-weight:800;text-decoration:underline;text-underline-offset:4px}.results-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:17px}.pdf-card{background:white;border:1px solid #e4eaf0;border-radius:16px;padding:19px 19px 16px;display:flex;flex-direction:column;min-height:255px;transition:transform .2s,box-shadow .2s}.pdf-card:hover{transform:translateY(-3px);box-shadow:0 12px 26px #0a24401c}.pdf-top{display:flex;justify-content:space-between;align-items:center;gap:8px}.pdf-symbol{width:43px;height:43px;border-radius:12px;display:grid;place-items:center;font:900 23px Georgia,serif}.kind-lesson{background:#e8f2fd;color:#215e90}.kind-exercise{background:#fdf1e1;color:#ab7428}.kind-exam{background:#eaf7ee;color:#24815b}.kind-test{background:#f7eafd;color:#7847ad}.pdf-type{font-size:11px;padding:4px 12px;border:1px solid #e7eef5;border-radius:50px;color:#6a7d91;background:#fafbfd}.pdf-title{font-size:16px;font-weight:800;line-height:1.72;color:#1d3d5f;margin:18px 0 9px;overflow-wrap:anywhere;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.pdf-meta{font-size:11px;color:#78899a;display:flex;gap:7px;align-items:center;flex-wrap:wrap;margin:0 0 18px}.pdf-actions{display:flex;gap:10px;margin-top:auto;padding-top:13px;border-top:1px solid #f0f2f5}.file-open{display:flex;align-items:center;justify-content:center;flex:1;text-decoration:none;background:#eef5fa;color:#1a5078;font-size:13px;font-weight:800;border-radius:9px;padding:8px}.file-open:hover{background:#dcebf6}.fav-btn{border:1px solid #e4eaf0;border-radius:9px;width:39px;min-width:39px;background:#fff;color:#b27251;font-size:20px}.fav-btn[aria-pressed='true']{color:#db6579;background:#fff5f6;border-color:#f4d8df}.pagination-wrap{display:flex;justify-content:center;margin-top:28px}.btn-more{background:#143f63;color:#fff;padding-inline:34px}.empty-state{text-align:center;background:white;border-radius:15px;padding:48px 20px;border:1px dashed #d3dfe8}.empty-state>span{display:block;color:#86a3bc;font-size:65px;line-height:1}.empty-state h3{margin:8px 0}.empty-state p{color:#657f94}.empty-state[hidden],#loadMore[hidden]{display:none}.small-print{font-size:12px;line-height:2;color:#7b8b9b;margin:20px 0 0}
.app-section{background:#f7f9fc;padding-top:30px}.app-banner{background:linear-gradient(117deg,#0e2d4c,#0a213c);border-radius:25px;color:white;min-height:345px;padding:50px 70px;overflow:hidden;display:grid;grid-template-columns:1.4fr .6fr;align-items:center;position:relative}.app-banner:before{content:'∑';position:absolute;top:-170px;left:170px;font:900 420px Georgia,serif;color:#ffffff06;pointer-events:none}.app-banner .section-label{color:#f0c87a}.app-banner h2{font-size:39px}.app-banner p{max-width:500px;color:#bbd0e1;margin:0 0 24px}.app-illustration{display:flex;justify-content:center;align-self:stretch;align-items:center}.phone{width:177px;height:300px;border:7px solid #3b5973;border-radius:27px;background:#06172a;padding:6px;box-shadow:14px 20px 60px #020d1f99;transform:rotate(-9deg);position:relative}.phone-notch{height:13px;width:66px;background:#06172a;border-radius:0 0 13px 13px;position:absolute;top:7px;left:50%;transform:translateX(-50%);z-index:1}.phone-screen{height:100%;background:linear-gradient(135deg,#11355a,#145a88);border-radius:17px;text-align:center;padding:31px 13px}.screen-logo{width:54px;height:54px;border-radius:16px;margin:auto;background:#123d69;display:grid;place-items:center;color:#f3c77b;font-size:25px;font-weight:900;letter-spacing:-5px}.screen-logo span{color:#51d0d5;font-size:16px}.screen-title{font:800 16px Arial,sans-serif;margin:13px auto 0;direction:ltr}.screen-subtitle{font:600 7px Arial,sans-serif;letter-spacing:2px;color:#dac89a;direction:ltr}.screen-line{width:42px;height:3px;border-radius:5px;background:#e3b76a;margin:16px auto}.screen-pill{font:15px Georgia,serif;background:#ffffff13;border:1px solid #ffffff27;border-radius:8px;padding:11px 1px;direction:ltr}.screen-grid{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-top:16px}.screen-grid i{height:18px;background:#ffffff1e;border-radius:7px}
.site-footer{background:#071e36;color:#abc0d1;padding:56px 0 0}.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1.1fr;gap:60px}.footer-grid p{max-width:360px;font-size:13px;line-height:2.2;color:#98b1c4}.footer-grid h3{color:#f5f8fc;margin:0 0 12px;font-size:15px}.footer-grid a:not(.brand){display:block;color:#abc0d1;text-decoration:none;font-size:13px;margin:10px 0}.footer-grid a:hover{color:var(--gold)}.footer-bottom{margin-top:37px;border-top:1px solid #ffffff1c;padding:18px 0;display:flex;justify-content:space-between;gap:20px;color:#7d9db7;font-size:12px}.simple-footer{text-align:center;padding:20px}.legal-nav{background:#0c2747;color:white;padding:17px 0}.legal-nav .container{display:flex;justify-content:space-between;align-items:center;gap:20px}.back-link{font-size:14px;text-decoration:none;color:var(--goldlight)}.legal-page{min-height:65vh;padding:75px 0}.legal-content{background:white;border-radius:20px;padding:50px 56px;max-width:850px;box-shadow:var(--shadow)}.legal-content h1{font-size:36px;margin:7px 0 35px}.legal-content h2{font-size:20px;margin:34px 0 12px;color:#16476e}.legal-content p{line-height:2.2;color:#50687e}
@media(max-width:1000px){.nav-links{gap:17px}.hero-grid{gap:10px}.hero h1{font-size:49px}.float-a{right:-6px}.float-b{left:-6px}.results-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.levels-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:750px){.container{width:min(100% - 30px,680px)}.nav-wrap{min-height:68px}.nav-links{display:none}.nav-play{padding:8px 11px;font-size:12px}.menu-btn{display:inline-grid;place-items:center}.nav-actions{display:flex;gap:8px;align-items:center}.brand-logo{width:43px;height:43px}.brand-words strong{font-size:18px}.hero{padding:64px 0 50px}.hero-grid{grid-template-columns:1fr}.hero h1{font-size:clamp(39px,9vw,61px)}.hero-visual{height:310px;max-width:500px;width:100%;margin:20px auto 0}.math-panel{width:min(390px,84%)}.float-a{right:2px}.float-b{left:5px}.trust-grid{grid-template-columns:repeat(2,1fr);gap:0}.trust-grid>div{padding:12px 0}.trust-grid>div:nth-child(even){border:0}.trust-grid>div:nth-child(-n+2){border-bottom:1px solid var(--border)}.section{padding:55px 0}.benefits-grid{grid-template-columns:1fr}.benefit{padding:25px}.benefit-icon{margin-bottom:12px}.library-heading{align-items:flex-start}.library-heading-badge{display:none}.app-banner{grid-template-columns:1fr 160px;padding:30px 30px}.app-banner h2{font-size:29px}.phone{transform:rotate(-7deg) scale(.76)}.footer-grid{grid-template-columns:1fr 1fr;gap:25px}.footer-grid>div:first-child{grid-column:1/-1}.legal-content{padding:28px 20px}}
@media(max-width:530px){.announcement{font-size:10px}.hero h1{letter-spacing:-1px;font-size:43px}.hero-lead{font-size:14px}.hero-visual{height:255px}.math-panel{padding:16px;width:80%}.panel-formula{font-size:19px}.graph{height:125px}.float-card{padding:9px}.float-card span{height:26px;width:26px;font-size:11px}.float-card strong{font-size:10px}.float-a{top:12px;right:-4px}.float-b{bottom:0;left:-4px}.section-intro p{font-size:13px}.levels-grid{grid-template-columns:repeat(2,1fr);gap:10px}.level-card{padding:18px 14px;min-height:168px}.level-name{font-size:14px}.level-sub{font-size:10px}.level-number{font-size:28px;margin-bottom:18px}.library-shell{padding:16px}.filter-row{grid-template-columns:1fr 1fr}.filter-row label:nth-child(3){grid-column:1/-1}.results-grid{grid-template-columns:1fr}.pdf-card{min-height:220px}.quick-filters{gap:6px}.chip{padding:6px 11px;font-size:11px}.results-top p{font-size:12px}.app-banner{grid-template-columns:1fr;min-height:auto;text-align:center;padding:35px 20px}.app-banner p{font-size:13px}.app-banner .app-illustration{display:none}.footer-grid{grid-template-columns:1fr}.footer-grid>div:first-child{grid-column:auto}.footer-bottom{flex-direction:column;gap:5px}.nav-play{font-size:11px}.brand-words strong{font-size:16px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}

/* Accessibility: anchored sections remain visible under sticky header */
:where(#main,#benefits,#levels,#library,#about){scroll-margin-top:100px}
:focus-visible{outline:3px solid #2ba3c5;outline-offset:3px}