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@media(max-width:600px){.container{width:min(100% - 24px,1160px)}.nav-wrap{height:66px}.brand{font-size:18px}.nav{gap:10px}.nav>a{font-size:12px}.nav-pill{padding:8px 10px}.hero{padding:48px 0 70px}.hero h1{font-size:47px}.lead{font-size:16px}.proof-row{grid-template-columns:1fr}.hero-photo,.photo-placeholder{height:420px;border-radius:24px}.section{padding:75px 0}.feature-grid,.reviews-grid,.materials-grid,.teacher-actions-grid{grid-template-columns:1fr}.portal-section{padding-bottom:75px}.portal{padding:30px 24px}.final-box{padding:36px 25px}.dashboard-page{padding-top:35px}.dashboard-head h1{font-size:36px}.student-avatar{display:none}.stats{gap:8px}.stats>div{padding:14px}.stats strong{font-size:22px}.task-head{display:block}.task-head time{display:block;margin-top:8px}.auth-card{padding:26px 20px}.footer-wrap{display:block}.footer-wrap>div+div{margin-top:12px}}
/* Unified teaching workspace */
:root{--bg:#f2f6f7;--ink:#142f34;--muted:#526b70;--green:#087e78;--green2:#05605c;--mint:#daf3eb;--line:#dce7e8;--dark:#113b40;--shadow:0 18px 48px #163a4012}body{font-size:16px}h1,h2,h3{overflow-wrap:anywhere}h1{line-height:1.13!important;letter-spacing:-.035em!important}p{overflow-wrap:anywhere}input,select,textarea,button{font:inherit}input,select,textarea{min-width:0;max-width:100%}textarea{min-height:110px}label,small,.nav>a,.button,.proof-row span{font-size:.875rem}.container{width:min(1240px,calc(100% - 48px))}.site-header{background:#ffffffed}.nav-wrap{gap:18px}.nav{gap:18px}.nav>a[href^='/#']{display:none}.hero{background:#eef7f7;padding:76px 0 90px}.hero-grid{gap:60px}.hero h1{font-size:clamp(2.8rem,5.6vw,4.9rem);line-height:1.09!important}.hero-photo{height:560px;object-position:50% 24%;border-radius:24px}.portrait-type{padding:48px;background:#103f44;color:#fff;border-radius:24px;min-height:520px;display:flex;flex-direction:column;justify-content:space-between}.portrait-type>span{letter-spacing:.15em;font-size:.875rem;color:#a9e7dc}.portrait-type>strong{font-size:clamp(3rem,5vw,5.1rem);line-height:1.12;letter-spacing:-.04em}.portrait-type p{color:#c3dedf}.floating-card{display:none}.button{min-height:44px;border-radius:10px}.button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #edb948;outline-offset:4px}.button:disabled{opacity:.6;cursor:wait}.button.tiny{font-size:.875rem}.section{padding:80px 0}.dashboard-page{padding-top:42px}.dashboard-head h1{font-size:clamp(2rem,4vw,3.1rem)}.dashboard-head{margin-bottom:20px}.workspace-nav{display:flex;gap:12px;flex-wrap:wrap;margin:20px 0}.workspace-nav a{padding:10px 16px;border:1px solid var(--line);border-radius:99px;background:white;text-decoration:none;font-weight:600;font-size:.875rem}.overview{display:grid;grid-template-columns:1.65fr 1fr;gap:24px;margin:24px 0}.overview .side-panel{margin:0}.big-number{font-size:3rem;line-height:1.4;display:block;color:var(--green)}.big-number small{font-size:1.3rem;color:var(--muted)}progress{width:100%;height:12px;accent-color:var(--green);border:none;border-radius:10px;overflow:hidden}progress::-webkit-progress-bar{background:#e5eded}progress::-webkit-progress-value{background:var(--green);border-radius:10px}.lesson-card{display:flex;align-items:flex-start;gap:22px;padding:22px 0;border-bottom:1px solid var(--line)}.lesson-card h3{margin:8px 0}.lesson-card p{margin:6px 0;color:var(--muted)}.lesson-date{background:var(--mint);color:var(--green2);padding:12px;border-radius:12px;text-align:center;min-width:78px}.lesson-date b{display:block;font-size:2rem;line-height:1.2}.lesson-date span{font-size:.875rem}.lesson-edit{padding:12px 0 24px}.dash-title{display:flex;gap:16px;align-items:center;justify-content:space-between}.dash-title>a{font-size:.875rem}.task-card,.side-panel,.panel{border:1px solid var(--line);box-shadow:0 4px 18px #163a4005;border-radius:16px}.task-head time{font-size:.875rem}.status{font-size:.875rem}.status-assigned{background:#fff0d4;color:#75501a}.status-submitted{background:#e2f0ff;color:#24527b}.status-checked{background:#daf3eb;color:#135b49}.task-card p,.teacher-task p,.teacher-comment{white-space:pre-wrap}.attachment{padding:12px 16px;background:#e7f4f3;border-radius:8px;font-weight:600}.notice{position:static;transform:none;margin:16px auto;max-width:calc(100% - 48px);width:fit-content;background:#145c52}.stats>div{box-shadow:none}.dashboard-grid>*{min-width:0}.faq{max-width:820px}.faq details{border-bottom:1px solid var(--line);padding:20px 0}.faq summary{font-size:1.125rem;cursor:pointer}.demo-label{font-size:.875rem;color:#c3dedf}.mobile-menu{display:none}.consent{display:block!important;font-size:.875rem}.consent input{width:auto;display:inline-block;vertical-align:middle}.footer-wrap a{font-size:.875rem}.panel>h1{margin-top:0}.page>.panel{padding:36px}.auth-card h1{font-size:2rem}.table-wrap{overflow:auto}.table-wrap th,.table-wrap td{font-size:.875rem}.review-form{min-width:0}.teacher-actions-grid{align-items:start}
@media(max-width:850px){.nav{display:none}.mobile-menu{display:block}.mobile-menu>summary{cursor:pointer;border:1px solid var(--line);padding:8px 14px;border-radius:8px}.mobile-menu nav{position:absolute;right:16px;top:65px;display:flex;flex-direction:column;background:white;border:1px solid var(--line);padding:16px;box-shadow:var(--shadow);border-radius:12px;gap:15px;min-width:220px}.mobile-menu nav a{padding:5px}.overview{grid-template-columns:1fr}.hero-grid{grid-template-columns:1fr}.portrait-type{min-height:300px}.hero-visual{max-width:100%;width:100%}.hero-photo{height:450px}.teacher-actions-grid{grid-template-columns:1fr}.dashboard-grid{grid-template-columns:1fr}.hero{padding:44px 0}.hero-grid{gap:32px}.section{padding:50px 0}}
@media(max-width:540px){.container{width:calc(100% - 28px)}.page>.panel{padding:20px}.hero h1{font-size:2.7rem}.hero-photo{height:390px}.portrait-type{padding:30px}.lesson-card{gap:12px}.lesson-date{min-width:66px;padding:10px}.task-head{display:block}.task-head time{display:block;margin-top:10px}.stats{grid-template-columns:repeat(2,1fr)}.overview{gap:16px}.side-panel{padding:20px}.dashboard-head .student-avatar{display:none}.nav-wrap{height:68px}.dashboard-page{padding-top:28px}.proof-row{gap:12px}.proof-row strong{font-size:1rem}.proof-row span{font-size:.875rem}.teacher-task{display:block}.auth-card{padding:24px}.hero-actions .button{width:100%}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
.demo-banner{background:#fff0d4;color:#614914;text-align:center;padding:8px 16px;font-size:.875rem;font-weight:600}
/* Chemistry studio */
.premium-hero{background:radial-gradient(ellipse at 90% 15%,#d4ede7 0,transparent 52%),linear-gradient(125deg,#f8fbfc,#edf5f5);border-bottom:1px solid #cadfdf;padding:90px 0 110px;overflow:hidden}.premium-hero .eyebrow{letter-spacing:.16em;font-size:.875rem;color:#286661}.premium-hero h1{font-weight:650;letter-spacing:-.055em!important;margin:25px 0}.premium-hero h1 span{font-family:Georgia,'Times New Roman',serif;font-style:italic;font-weight:400;color:#08766d}.premium-hero .lead{max-width:540px;line-height:1.75}.premium-hero .hero-grid{gap:64px;grid-template-columns:1.15fr 1fr;align-items:center}.premium-hero .hero-visual{position:relative;padding:25px 0 35px}.premium-hero .portrait-type{background:linear-gradient(145deg,#103f44,#062e32);border:1px solid #31716f;box-shadow:0 26px 65px #0d47432a;border-radius:120px 24px 24px 24px;padding:65px 40px 100px;min-height:500px}.premium-hero .portrait-type strong{font-family:Georgia,serif;font-weight:400;font-size:clamp(3rem,4.8vw,4.7rem)}.premium-hero .portrait-type>span{font-size:.875rem}.premium-hero .hero-photo{border-radius:120px 24px 24px 24px;box-shadow:0 26px 65px #0d47432a;width:100%}.chem-equation{position:absolute;top:0;right:16px;background:#fff;border:1px solid #c6deda;padding:12px 22px;border-radius:12px;color:#125953;font:italic 1.2rem Georgia,serif;box-shadow:0 8px 24px #174a4612}.element-strip{position:absolute;bottom:0;right:24px;display:flex;gap:10px}.element-strip>div{display:grid;background:#f9fdfb;border:1px solid #accfc6;border-radius:12px;padding:10px 16px;min-width:88px;box-shadow:0 8px 20px #153d3d15;color:#184d46}.element-strip small{font-size:.75rem}.element-strip b{font-size:2rem;line-height:1.2;font-weight:500}.element-strip span{font-size:.75rem}.premium-hero .proof-row{border-top:1px solid #bcd5d1;padding-top:25px;margin-top:36px}.premium-hero .button{border-radius:12px;padding:15px 20px;box-shadow:0 6px 16px #126c6412}.premium-hero .telegram-button{background:#fff;border:1px solid #8bb7ad;color:#195c54;box-shadow:none}.feature-grid>article{border-top:3px solid #238878;box-shadow:0 12px 28px #19494308}.feature-num{font-family:Georgia,serif;font-size:2rem;color:#08766d}.file-field{border:1px dashed #78a99e;padding:16px;border-radius:12px;background:#f1f9f6}.file-field input{background:white;padding:10px;font-size:.875rem}.file-field small{font-weight:400;color:#48665e;line-height:1.5}.file-field input::file-selector-button{border:0;border-radius:7px;background:#d7eee6;color:#194c42;padding:8px 10px;margin-right:10px;cursor:pointer}.attachment a{overflow-wrap:anywhere}.material-card>div{min-width:0;width:100%}.material-card a{display:inline-block;margin-top:8px}.stack-form label,.compact-form label{font-size:.875rem}
@media(max-width:900px){.premium-hero .hero-grid{grid-template-columns:1fr;gap:30px}.premium-hero{padding:50px 0 65px}.premium-hero .hero-visual{max-width:560px;margin:auto}.premium-hero .portrait-type{min-height:430px}.premium-hero .hero-photo{height:480px}.premium-hero h1{font-size:clamp(2.6rem,7vw,4.6rem)}}
@media(max-width:540px){.premium-hero .portrait-type{border-top-left-radius:70px;padding:50px 28px 95px;min-height:400px}.premium-hero .hero-photo{height:410px;border-top-left-radius:70px}.element-strip{right:12px;gap:7px}.element-strip>div{min-width:75px;padding:9px 12px}.chem-equation{font-size:1rem;padding:10px 16px}.premium-hero .proof-row{grid-template-columns:1fr}.premium-hero .hero-actions{gap:10px}}

/* Academy workspace */
.academy-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:20px;margin:24px 0}.academy-nav{flex-wrap:wrap;gap:10px}.academy-nav a{border:1px solid #d0e3df;border-radius:30px;padding:10px 16px;background:#fff}.metric{background:#e9f4f1;border:1px solid #d1e6df;border-radius:22px;padding:24px}.metric span{display:block;color:#47675f}.metric strong{display:block;font-size:38px;line-height:1.3;margin-top:14px;font-variant-numeric:tabular-nums}.question-editor{padding:16px;border:1px solid #d4e5e0;border-radius:14px;margin:12px 0}.question-editor label{display:block;margin-top:12px}.quiz-option{display:flex;align-items:center;gap:12px;padding:12px;border:1px solid #d5e7df;border-radius:12px;margin:8px 0;cursor:pointer}.quiz-option input{width:auto}.quiz-timer{position:sticky;top:12px;background:#153f37;color:#fff;padding:16px;border-radius:12px;z-index:3}.grade-history{display:flex;gap:14px;overflow:auto;padding:12px 0}.grade-point{min-width:155px;max-width:180px;background:#edf5f2;border-radius:16px;padding:18px;display:flex;flex-direction:column;gap:10px}.grade-point strong{font-size:32px}.grade-point small{color:#537065}.knowledge-filter{display:flex;align-items:end;flex-wrap:wrap;gap:16px;margin:20px 0}.knowledge-filter label{flex:1;min-width:150px}.table-scroll,.periodic-scroll{overflow-x:auto;margin:24px 0}table{width:100%;border-collapse:collapse}td,th{text-align:left;padding:14px;border-bottom:1px solid #d9e6df}.preserve{white-space:pre-wrap}.periodic-table{display:grid;grid-template-columns:repeat(18,minmax(57px,1fr));grid-template-rows:repeat(9,76px);gap:4px;min-width:1120px}.element-tile{background:#e6f4ed;border:1px solid #bfd8cf;border-radius:7px;cursor:pointer;color:#163e33;padding:5px;text-align:left}.element-tile:hover,.element-tile:focus-visible{background:#153f37;color:white;outline:2px solid #b79b63}.element-tile b{display:block;font-size:23px}.element-tile span{display:block;font-size:8px;overflow:hidden}.element-tile small{font-size:10px}.element-tile[hidden]{visibility:hidden;display:block}.period-8,.period-9{background:#f4eddf}.task-card fieldset,fieldset.task-card{min-width:0}summary{cursor:pointer}legend{font-weight:700}.compact-form textarea{min-height:100px}@media(max-width:600px){.academy-grid{grid-template-columns:1fr}.metric strong{font-size:32px}.academy-nav a{font-size:13px}.panel{overflow-wrap:anywhere}.knowledge-filter{display:grid;grid-template-columns:1fr}.question-editor{padding:10px}}
.period-1{grid-row:1}
.period-2{grid-row:2}
.period-3{grid-row:3}
.period-4{grid-row:4}
.period-5{grid-row:5}
.period-6{grid-row:6}
.period-7{grid-row:7}
.period-8{grid-row:8}
.period-9{grid-row:9}
.group-1{grid-column:1}
.group-2{grid-column:2}
.group-3{grid-column:3}
.group-4{grid-column:4}
.group-5{grid-column:5}
.group-6{grid-column:6}
.group-7{grid-column:7}
.group-8{grid-column:8}
.group-9{grid-column:9}
.group-10{grid-column:10}
.group-11{grid-column:11}
.group-12{grid-column:12}
.group-13{grid-column:13}
.group-14{grid-column:14}
.group-15{grid-column:15}
.group-16{grid-column:16}
.group-17{grid-column:17}
.group-18{grid-column:18}