:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color-scheme:dark;--bg:#071019;--panel:#101b27;--panel2:#142231;--line:#26394b;--text:#edf4fb;--muted:#98aabd;--lime:#e7f35b;--cyan:#71d8ff;--good:#9ef01a;--bad:#ff8585}*{box-sizing:border-box}body{margin:0;background:radial-gradient(circle at 20% 0,#132437 0,transparent 28%),var(--bg);color:var(--text)}a{color:var(--cyan)}.site-header{display:flex;justify-content:space-between;align-items:center;padding:16px max(24px,calc((100vw - 1280px)/2));background:rgba(8,17,27,.92);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20;backdrop-filter:blur(12px)}.brand{display:flex;gap:12px;align-items:center;color:var(--text);text-decoration:none}.brand span:last-child{display:flex;flex-direction:column}.brand small{color:var(--muted);font-size:.72rem;letter-spacing:.08em;text-transform:uppercase}.brand-mark{display:grid;place-items:center;width:40px;height:40px;border-radius:11px;background:var(--lime);color:#10140a;font-weight:900}.user-chip{font-size:.9rem;color:var(--muted)}main{max-width:1280px;margin:0 auto;padding:34px 24px 70px}footer{text-align:center;color:#65798d;padding:24px;border-top:1px solid #132333}.hero{display:grid;grid-template-columns:1fr auto;gap:28px;align-items:end;padding:32px 0 38px}.hero h1,.course-header h1,.login-wrap h1{font-size:clamp(2.2rem,5vw,4.2rem);line-height:1.02;margin:.25rem 0 1rem;letter-spacing:-.045em}.hero p,.course-header p,.login-wrap>div>p{font-size:1.08rem;color:var(--muted);max-width:780px;line-height:1.65}.eyebrow{color:var(--lime);font-size:.73rem;letter-spacing:.17em;font-weight:900}.hero-stat{min-width:220px;background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:20px}.hero-stat strong{font-size:2rem}.hero-stat span{display:block;color:var(--muted);margin-top:4px}.progress{height:7px;background:#263342;border-radius:10px;margin-top:16px;overflow:hidden}.progress i{display:block;background:var(--lime);height:100%}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(275px,1fr));gap:18px}.card{background:linear-gradient(180deg,rgba(20,34,49,.96),rgba(14,26,38,.96));border:1px solid var(--line);border-radius:18px;padding:22px;box-shadow:0 18px 55px rgba(0,0,0,.14)}.module-card{display:flex;flex-direction:column;min-height:315px}.module-card h3{font-size:1.18rem;margin:.9rem 0 .5rem}.module-card p{color:var(--muted);line-height:1.5;flex:1}.module-top{display:flex;justify-content:space-between;align-items:center}.module-number{font-size:1.55rem;font-weight:900;color:#72869a}.badge,.pill{font-size:.72rem;padding:5px 9px;border-radius:999px;background:#1c3143;color:#bdd2e5}.module-meta{display:flex;gap:20px;border-top:1px solid var(--line);padding-top:14px;margin-top:10px;color:var(--muted);font-size:.85rem}.module-meta b{color:var(--text)}.status{border-radius:10px;padding:9px 11px;font-size:.82rem;font-weight:700;margin:12px 0}.status.passed{background:rgba(158,240,26,.12);color:#bdfb5d}.status.ready{background:rgba(113,216,255,.1);color:#a4e8ff}.status.danger{background:rgba(255,133,133,.12);color:#ffb2b2}.wide{display:block}.locked{opacity:.45}.button,button{display:inline-block;background:var(--lime);color:#0c1206;border:0;border-radius:10px;padding:11px 15px;font-weight:850;text-decoration:none;cursor:pointer;font:inherit;font-weight:800}.secondary-btn,.ghost-link{background:#243749;color:#eef5fb}.ghost{background:transparent;color:var(--cyan);border:1px solid #34506a}.full{width:100%;text-align:center;margin-top:9px}.back{display:inline-block;margin-bottom:20px;text-decoration:none}.course-header{padding:12px 0 28px;max-width:940px}.course-layout{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:22px}.lesson{display:grid;grid-template-columns:50px 1fr;gap:18px}.section-number{display:grid;place-items:center;width:42px;height:42px;border-radius:12px;background:#213547;color:var(--lime);font-size:1.3rem;font-weight:900}.lesson h2{margin:3px 0 10px}.checklist{padding:0;list-style:none}.checklist li{margin:10px 0;color:#cad7e3}.checklist li:before{content:'✓';color:var(--lime);font-weight:900;margin-right:10px}.tip-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:10px}.tip{background:#0b1621;border:1px solid #26394b;border-radius:12px;padding:14px}.tip strong,.tip span{display:block}.tip span{color:var(--muted);margin-top:5px;line-height:1.45}.worked{background:#0a1520;border-left:3px solid var(--cyan);border-radius:8px;padding:15px;margin:12px 0}.worked .problem{font-size:1.1rem;font-weight:900;margin-bottom:7px}.worked-answer{color:var(--lime);margin-top:6px;font-weight:800}.sample{border-top:1px solid var(--line);padding:12px 0}.sample summary{cursor:pointer;font-weight:800}.sample p{color:var(--muted)}.sticky{position:sticky;top:94px}.course-sidebar p{color:var(--muted);line-height:1.55}.no-retake{margin-top:12px;padding:12px;border-radius:10px;background:#0b1621;color:#9fb0c1;font-size:.85rem}.quiz-shell{max-width:760px;margin:25px auto}.quiz-progress{display:flex;justify-content:space-between;color:var(--muted);padding:0 3px 12px}.quiz-card{padding:32px}.quiz-card h1{font-size:2rem;margin:12px 0 20px}.hint{padding:13px;background:#192838;border-left:4px solid var(--lime);margin:12px 0;border-radius:6px}.feedback{display:flex;flex-direction:column;gap:5px;padding:14px 18px;border-radius:12px;margin-bottom:12px}.good-box{background:rgba(158,240,26,.12);border:1px solid rgba(158,240,26,.25)}.bad-box{background:rgba(255,133,133,.12);border:1px solid rgba(255,133,133,.25)}input{box-sizing:border-box;width:100%;margin:8px 0;padding:13px;border-radius:9px;border:1px solid #344b60;background:#09131d;color:white;font:inherit}label{font-size:.82rem;color:var(--muted)}.tiny{font-size:.75rem}.muted{color:var(--muted)}.flash{padding:12px 16px;background:#24384d;border-radius:10px;margin-bottom:16px}.result-layout{display:grid;grid-template-columns:minmax(280px,.7fr) 1.3fr;gap:20px}.result-card .score{font-size:5rem;font-weight:950;color:var(--lime);letter-spacing:-.06em}.wrong-item{display:flex;flex-direction:column;gap:4px;padding:13px 0;border-bottom:1px solid var(--line)}.wrong-item span{color:#c4d0db}.wrong-item small{color:var(--muted)}.parent-hero{align-items:center}.button-stack{display:flex;gap:8px}.admin-grid{display:grid;grid-template-columns:2fr 1fr;gap:18px;margin-bottom:20px}.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:8px}.student-panel{margin:22px 0;padding:26px}.student-heading{display:flex;justify-content:space-between;gap:20px;align-items:start}.student-heading h2{margin:5px 0;font-size:1.7rem}.student-heading small{font-size:.85rem;color:var(--muted);font-weight:500}.metric-strip{display:flex;gap:12px}.metric-strip div{min-width:82px;background:#0b1621;border:1px solid #26394b;border-radius:12px;padding:10px;text-align:center}.metric-strip strong,.metric-strip span{display:block}.metric-strip strong{font-size:1.2rem}.metric-strip span{font-size:.7rem;color:var(--muted)}.admin-details{margin:16px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:10px 0}.admin-details summary{cursor:pointer;font-weight:800}.split{display:grid;grid-template-columns:1fr 1fr;gap:15px;padding-top:12px}.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse}th,td{text-align:left;padding:11px 9px;border-bottom:1px solid #26394b}th{color:#a5b6c7;font-size:.77rem;text-transform:uppercase;letter-spacing:.05em}.pill.ok{background:rgba(158,240,26,.12);color:#c4fb72}.pill.warn{background:rgba(255,190,75,.12);color:#ffd184}.analytics-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px;margin:22px 0}.mini-list>div{display:flex;justify-content:space-between;gap:10px;border-bottom:1px solid var(--line);padding:9px 0}.mini-list span{color:var(--muted)}.wrong-table{border:1px solid var(--line);border-radius:12px;overflow:hidden}.wrong-row{display:grid;grid-template-columns:2fr .7fr .7fr auto;gap:15px;padding:12px 14px;border-bottom:1px solid var(--line);align-items:center}.wrong-row:last-child{border:0}.wrong-row small,.wrong-row b{display:block}.wrong-row small{color:var(--muted);margin-top:3px}.label{font-size:.65rem;color:var(--muted);text-transform:uppercase;display:block}.flags span{display:inline-block;font-size:.68rem;background:#23384a;padding:5px 7px;border-radius:7px;margin:2px}.flags .flag-red{background:rgba(255,133,133,.15);color:#ffb2b2}.login-wrap{display:grid;grid-template-columns:1.3fr .7fr;gap:60px;align-items:center;min-height:70vh}.login-card{max-width:430px}.button-row{display:flex;gap:8px}.narrow{max-width:620px;margin:30px auto}@media(max-width:850px){.course-layout,.result-layout,.admin-grid,.login-wrap{grid-template-columns:1fr}.hero{grid-template-columns:1fr}.course-sidebar .sticky{position:static}.student-heading{flex-direction:column}.metric-strip{flex-wrap:wrap}.wrong-row{grid-template-columns:1fr 1fr}.analytics-grid{grid-template-columns:1fr}.button-stack{flex-direction:column}}@media(max-width:520px){main{padding:22px 14px 60px}.site-header{padding:12px 14px}.lesson{grid-template-columns:1fr}.section-number{width:34px;height:34px}.wrong-row{grid-template-columns:1fr}.metric-strip{display:grid;grid-template-columns:1fr 1fr;width:100%}.metric-strip div{min-width:0}}

/* v5 course chapters + platform admin */
.chapter{margin-bottom:18px}.chapter-label{font-size:.7rem;letter-spacing:.16em;font-weight:900;color:var(--cyan)}.lesson-prose{font-size:1.02rem;line-height:1.78;color:#c8d6e3;max-width:850px}.mental-model{margin:18px 0;padding:16px 18px;border-radius:12px;background:linear-gradient(135deg,rgba(231,243,91,.1),rgba(113,216,255,.07));border:1px solid rgba(231,243,91,.22)}.mental-model b,.mental-model span{display:block}.mental-model b{color:var(--lime);margin-bottom:5px}.reason-list{display:grid;gap:10px}.reason{display:grid;grid-template-columns:34px 1fr;gap:12px;align-items:start;padding:13px;border:1px solid var(--line);background:#0b1621;border-radius:12px}.reason>span{display:grid;place-items:center;width:30px;height:30px;border-radius:9px;background:#20374a;color:var(--lime);font-weight:900}.reason p{margin:3px 0;color:#c8d6e3;line-height:1.55}.mistake-list{list-style:none;padding:0}.mistake-list li{padding:12px 14px 12px 42px;margin:8px 0;border-radius:10px;background:rgba(255,133,133,.06);border:1px solid rgba(255,133,133,.14);position:relative;color:#d7e2eb}.mistake-list li:before{content:'!';position:absolute;left:14px;top:10px;color:#ff9e9e;font-weight:950;font-size:1.1rem}.strategy-flow{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:10px}.strategy-flow>div{padding:14px;background:#0b1621;border:1px solid var(--line);border-radius:12px}.strategy-flow b{display:grid;place-items:center;width:28px;height:28px;border-radius:8px;background:var(--lime);color:#0c1206;margin-bottom:8px}.strategy-flow span{color:#c3d1de;line-height:1.45}.course-nav .flow-item{display:grid;grid-template-columns:28px 1fr;gap:9px;align-items:start;margin:10px 0;color:#c4d1dd}.course-nav .flow-item b{display:grid;place-items:center;width:26px;height:26px;border-radius:8px;background:#203547;color:var(--lime)}
.admin-hero{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;padding:28px 0}.admin-hero.compact{align-items:center}.admin-hero h1{font-size:clamp(2.2rem,5vw,4rem);letter-spacing:-.045em;margin:.25rem 0 .7rem}.admin-hero p{color:var(--muted);font-size:1.05rem;max-width:720px}.stats{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:12px;margin:0 0 20px}.stat{background:linear-gradient(180deg,#142334,#0f1c29);border:1px solid var(--line);border-radius:16px;padding:17px;color:var(--text);box-shadow:0 14px 40px rgba(0,0,0,.14)}.stat span{display:block;color:var(--muted);font-size:.75rem;text-transform:uppercase;letter-spacing:.06em}.stat b{display:block;font-size:1.75rem;margin-top:5px}.stat.accent{border-color:rgba(231,243,91,.4);background:linear-gradient(180deg,rgba(231,243,91,.12),#101c28)}.panel{border-radius:18px;padding:22px;margin-bottom:18px}.dark-panel{background:linear-gradient(180deg,rgba(20,34,49,.98),rgba(14,26,38,.98));border:1px solid var(--line);color:var(--text)}.panel-head{display:flex;justify-content:space-between;gap:20px;align-items:end;margin-bottom:16px}.panel-head h2{margin:.25rem 0 0}.panel-head p{max-width:520px;color:var(--muted);margin:0}.admin-form{grid-template-columns:repeat(3,1fr);align-items:end}.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:10px}.form-grid label,.stack-form label{display:block;color:var(--muted);font-size:.77rem}.form-grid input,.form-grid select,.stack-form input,.stack-form select,.stack-form textarea{margin-top:5px;width:100%;padding:11px 12px;border-radius:9px;border:1px solid #344b60;background:#09131d;color:var(--text);font:inherit}.stack-form{display:grid;gap:11px}.split-fields{display:grid;grid-template-columns:1fr 1fr;gap:10px}.checkbox-row{display:flex!important;align-items:center;gap:9px}.checkbox-row input{width:auto!important;margin:0!important}.client-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(270px,1fr));gap:12px}.client-card,.student-admin-card{display:block;text-decoration:none;color:var(--text);padding:16px;border:1px solid var(--line);border-radius:14px;background:#0b1621}.client-card:hover{border-color:#4d6a83;transform:translateY(-1px)}.client-title{display:flex;justify-content:space-between;align-items:start;gap:10px}.client-title b,.client-title span{display:block}.client-title>div>span{color:var(--muted);font-size:.8rem;margin-top:4px}.status-dot{display:inline-block;padding:5px 9px;border-radius:999px;font-size:.68rem;font-weight:850;text-transform:uppercase;letter-spacing:.04em;background:#233446;color:#b9cadd}.status-active{background:rgba(158,240,26,.13);color:#c5fb70}.status-restricted{background:rgba(255,197,72,.13);color:#ffd476}.status-suspended{background:rgba(255,133,133,.14);color:#ffb0b0}.status-archived{background:#25303b;color:#9aabba}.status-dot.large{font-size:.8rem;padding:8px 13px}.client-metrics{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-top:15px}.client-metrics.four{grid-template-columns:repeat(4,1fr)}.client-metrics>div{padding:9px;border-radius:9px;background:#101f2d}.client-metrics span,.client-metrics b{display:block}.client-metrics span{font-size:.67rem;text-transform:uppercase;color:var(--muted)}.client-metrics b{margin-top:3px}.admin-two-col{display:grid;grid-template-columns:1fr 1fr;gap:18px}.mini-list>div{display:flex;justify-content:space-between;gap:18px;padding:10px 0;border-bottom:1px solid var(--line)}.mini-list span{color:#c5d2de}.mini-list b{font-size:.82rem;text-align:right}.audit{display:flex;justify-content:space-between;gap:18px;padding:11px 0;border-bottom:1px solid var(--line)}.audit b,.audit span{display:block}.audit span,.audit small{color:var(--muted)}.manage-user{border-top:1px solid var(--line);padding:13px 0}.manage-user summary{cursor:pointer;display:flex;justify-content:space-between;gap:15px}.manage-user summary div span{display:block;color:var(--muted);font-size:.8rem;margin-top:3px}.manage-user form{margin-top:14px}.student-admin-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(310px,1fr));gap:12px}.student-admin-card .manage-user{margin-top:12px}.student-admin-card .manage-user summary{color:var(--cyan);font-weight:800}select{color-scheme:dark}.button.ghost{background:transparent;border:1px solid #35516a;color:var(--cyan)}
@media(max-width:900px){.stats{grid-template-columns:repeat(2,1fr)}.admin-form,.admin-two-col{grid-template-columns:1fr}.client-metrics.four{grid-template-columns:1fr 1fr}.panel-head,.admin-hero{align-items:start;flex-direction:column}}@media(max-width:520px){.stats{grid-template-columns:1fr 1fr}.split-fields{grid-template-columns:1fr}}

/* v6 analytics + production polish */
main{padding-top:96px}.admin-hero{scroll-margin-top:100px}.admin-stats{grid-template-columns:repeat(6,minmax(0,1fr))}.metric-link{display:flex;justify-content:space-between;gap:18px;padding:10px 0;border-bottom:1px solid var(--line);text-decoration:none;color:inherit}.metric-link:hover span{color:var(--lime)}.metric-link span{color:#c5d2de}.metric-link b{font-size:.82rem;text-align:right}.student-link{color:var(--cyan);text-decoration:none}.student-link:hover{color:var(--lime)}.trend-list>div{display:grid;grid-template-columns:1.3fr 2fr 55px;gap:12px;align-items:center;padding:8px 0}.progress{height:10px;border-radius:999px;background:#09131d;overflow:hidden;border:1px solid var(--line)}.progress i{display:block;height:100%;background:linear-gradient(90deg,var(--cyan),var(--lime))}@media(max-width:1050px){.admin-stats{grid-template-columns:repeat(3,1fr)}}@media(max-width:650px){main{padding-top:82px}.admin-stats{grid-template-columns:repeat(2,1fr)}.trend-list>div{grid-template-columns:1fr}.metric-link{flex-direction:column;gap:4px}.metric-link b{text-align:left}}