:root{--ink:#101828;--muted:#667085;--line:#e7e9ee;--paper:#fbfbfa;--white:#fff;--navy:#13243a;--navy2:#1c3553;--accent:#9b7a45;--soft:#f3f0ea;--green:#176b52;--red:#a73a48}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Inter,"Helvetica Neue",Arial,sans-serif;letter-spacing:-.01em}
nav{height:72px;border-bottom:1px solid var(--line);background:rgba(251,251,250,.96);position:sticky;top:0;z-index:20;backdrop-filter:blur(12px)}
.navin{max-width:1180px;height:100%;margin:auto;padding:0 24px;display:flex;align-items:center;justify-content:space-between}.brand{display:flex;align-items:center;gap:13px;cursor:pointer}.seal{width:36px;height:36px;border:1px solid #a68b61;border-radius:50%;display:grid;place-items:center;font-family:Georgia,serif;color:var(--navy);font-size:18px}.brandname{font-size:15px;font-weight:750;letter-spacing:.01em}.brandname small{display:block;font-size:9px;letter-spacing:.2em;color:var(--muted);font-weight:600;margin-top:3px}.navmeta{font-size:12px;color:var(--muted)}
.wrap{max-width:1180px;margin:auto;padding:0 24px}.hero{padding:78px 0 58px;border-bottom:1px solid var(--line);display:grid;grid-template-columns:1.5fr .5fr;gap:50px}.eyebrow{text-transform:uppercase;font-size:10px;letter-spacing:.22em;font-weight:800;color:var(--accent)}h1{font-family:Georgia,"Times New Roman",serif;font-size:58px;line-height:1.02;letter-spacing:-.035em;margin:16px 0 20px;font-weight:500;color:var(--navy)}.hero p{font-size:17px;line-height:1.7;color:#4c5667;max-width:670px}.hero-side{align-self:end;padding-bottom:7px}.hero-side .big{font-family:Georgia,serif;font-size:44px;color:var(--navy)}.hero-side p{font-size:12px;margin:3px 0 12px}.meter{height:3px;background:#e2e4e8}.meter i{height:100%;display:block;background:var(--accent);width:0}
.levelnav{display:flex;gap:8px;flex-wrap:wrap;padding:30px 0 14px}.pill{border:1px solid var(--line);background:white;padding:8px 13px;border-radius:999px;font-size:12px;cursor:pointer}.pill.active{background:var(--navy);color:white;border-color:var(--navy)}
.sectiontitle{display:flex;align-items:end;justify-content:space-between;padding:28px 0 14px}.sectiontitle h2{font-family:Georgia,serif;font-weight:500;color:var(--navy);font-size:30px;margin:0}.sectiontitle span{font-size:12px;color:var(--muted)}
.coursegrid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;padding-bottom:65px}.card{background:white;border:1px solid var(--line);padding:20px;display:flex;gap:16px;align-items:flex-start;cursor:pointer;transition:.16s;border-radius:3px}.card:hover{border-color:#aeb6c1;box-shadow:0 8px 24px #1018280a}.n{font-family:Georgia,serif;font-size:20px;color:var(--accent);min-width:30px}.copy{flex:1}.copy b{font-size:15px;font-weight:700}.copy small{display:block;color:var(--muted);font-size:12px;line-height:1.5;margin-top:5px}.badge{font-size:9px;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);white-space:nowrap}.badge.done{color:var(--green)}
.lesson{max-width:860px;margin:42px auto 80px}.back{border:0;background:none;padding:0;color:var(--muted);font-weight:650;cursor:pointer;margin-bottom:26px}.lessonhead{border-bottom:1px solid var(--line);padding-bottom:27px;margin-bottom:28px}.lessonhead h1{font-size:43px;margin:10px 0 9px}.lessonhead p{color:var(--muted);line-height:1.6}.panel{background:white;border:1px solid var(--line);padding:28px;margin-bottom:14px;border-radius:3px}.panel h3{font-family:Georgia,serif;color:var(--navy);font-size:24px;font-weight:500;margin:0 0 15px}.rule{background:var(--soft);padding:16px 18px;border-left:2px solid var(--accent);line-height:1.6;margin:15px 0}.example{padding:14px 0;color:#3f4a5a;line-height:1.7}.q{padding:22px 0;border-top:1px solid var(--line)}.q:first-of-type{border-top:0}.qtitle{font-weight:650;margin-bottom:12px}.options{display:grid;gap:7px}.opt,input{font:inherit;border:1px solid #d8dce3;background:white;padding:12px 13px;text-align:left;border-radius:3px}.opt{cursor:pointer}.opt:hover,.opt.selected{border-color:#718099;background:#f8f9fa}input{width:100%}.check{border:0;background:var(--navy);color:white;padding:11px 16px;margin-top:10px;font-weight:700;border-radius:3px;cursor:pointer}.feedback{display:none;margin-top:10px;padding:12px 14px;font-size:13px;line-height:1.55}.feedback.ok{display:block;background:#edf7f3;color:#135f49}.feedback.bad{display:block;background:#fff1f2;color:#92303e}.result{margin-top:18px;border-top:1px solid var(--line);padding-top:18px}.result strong{font-family:Georgia,serif;font-size:32px;color:var(--navy)}footer{border-top:1px solid var(--line);padding:28px 0 45px;color:var(--muted);font-size:11px;letter-spacing:.08em;text-align:center}
@media(max-width:760px){.hero{grid-template-columns:1fr;padding:52px 0 40px}.hero-side{padding:0}h1{font-size:43px}.coursegrid{grid-template-columns:1fr}.navmeta{display:none}.wrap{padding:0 17px}.panel{padding:20px}.lessonhead h1{font-size:36px}}

/* Premium layer */
.utility{display:flex;gap:7px;align-items:center}.iconbtn{border:1px solid var(--line);background:white;height:34px;padding:0 11px;border-radius:999px;cursor:pointer;font-size:11px;color:var(--ink)}
.dashboard{padding:34px 0 6px}.welcome{display:grid;grid-template-columns:1.35fr .65fr;gap:12px}.dashmain,.dashside{background:white;border:1px solid var(--line);padding:27px;border-radius:3px}.dashmain h2{font-family:Georgia,serif;color:var(--navy);font-size:30px;font-weight:500;margin:7px 0}.dashmain p{color:var(--muted);line-height:1.6}.continue{display:inline-block;border:0;background:var(--navy);color:white;padding:12px 17px;font-weight:700;border-radius:3px;cursor:pointer;margin-top:6px}.stats{display:grid;grid-template-columns:1fr 1fr;gap:8px}.stat{background:var(--paper);border:1px solid var(--line);padding:14px}.stat b{font-family:Georgia,serif;font-size:25px;color:var(--navy);display:block}.stat small{color:var(--muted);font-size:10px;text-transform:uppercase;letter-spacing:.1em}
.method{margin:34px 0 8px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:29px 0;display:grid;grid-template-columns:.7fr 1.3fr;gap:35px}.method h3{font-family:Georgia,serif;color:var(--navy);font-size:27px;font-weight:500;margin:5px 0}.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.step{padding:13px;border-left:1px solid var(--line)}.step b{display:block;font-size:12px}.step span{font-size:11px;color:var(--muted);line-height:1.5}
.modal{position:fixed;inset:0;background:#0c1420a8;z-index:100;display:none;align-items:center;justify-content:center;padding:20px}.modal.show{display:flex}.modalbox{background:var(--paper);width:min(680px,100%);max-height:90vh;overflow:auto;padding:31px;border-radius:4px;box-shadow:0 25px 70px #0004}.modalbox h2{font-family:Georgia,serif;color:var(--navy);font-size:31px;font-weight:500;margin:7px 0 10px}.modalbox p{color:var(--muted);line-height:1.6}.close{float:right;border:0;background:none;font-size:22px;cursor:pointer}.field{margin:18px 0}.field label{display:block;font-size:11px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;margin-bottom:7px}.field input{background:white}.placement-q{padding:16px 0;border-top:1px solid var(--line)}.placement-q b{display:block;margin-bottom:9px}.cert{border:1px solid #b89c6c;background:#fff;padding:35px;text-align:center;margin-top:20px}.cert .seal{margin:0 auto 15px;width:52px;height:52px}.cert h2{font-size:34px;margin:7px}.cert p{margin:6px}.mistakeitem{padding:14px 0;border-bottom:1px solid var(--line)}.mistakeitem b{display:block;margin-bottom:5px}.mistakeitem small{color:var(--muted)}
.phasebar{display:flex;gap:7px;margin:16px 0 0}.phase{font-size:10px;letter-spacing:.08em;text-transform:uppercase;padding:7px 10px;border:1px solid var(--line);color:var(--muted)}.phase.on{background:var(--navy);color:white;border-color:var(--navy)}
body.dark{--paper:#0f141b;--white:#151c25;--ink:#edf0f4;--muted:#9ba6b5;--line:#2a3441;--navy:#e8edf3;--navy2:#dfe7ef;--soft:#1c2530;--accent:#c3a56f;background:var(--paper);color:var(--ink)}body.dark nav{background:#0f141bf2}body.dark .card,body.dark .panel,body.dark .dashmain,body.dark .dashside,body.dark .modalbox,body.dark .iconbtn,body.dark input,body.dark .opt{background:#151c25;color:var(--ink)}body.dark .continue,body.dark .check,body.dark .pill.active{background:#dce4ed;color:#111820}body.dark .hero p,body.dark .example{color:#aeb8c5}body.dark .stat{background:#10171f}body.dark .cert{background:#151c25}
@media(max-width:760px){.welcome,.method{grid-template-columns:1fr}.steps{grid-template-columns:1fr 1fr}.dashboard{padding-top:22px}.utility .hideMob{display:none}}
/* Lesson depth v3 */
.lessonintro{margin-bottom:16px}.learn-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:14px}.learnbox{border:1px solid var(--line);padding:18px;background:var(--white)}.learnbox h4{margin:0 0 9px;color:var(--navy);font-size:13px;text-transform:uppercase;letter-spacing:.07em}.learnbox p,.learnbox li{font-size:14px;line-height:1.65;color:var(--muted)}.learnbox ul{padding-left:18px;margin:8px 0}.formula{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;background:var(--soft);padding:12px 14px;margin:8px 0;font-size:13px;line-height:1.6}.warning{border-left:3px solid var(--accent);padding:11px 14px;background:var(--soft);font-size:14px;line-height:1.6}.goodbad{display:grid;gap:7px}.goodbad div{font-size:14px;line-height:1.5}.lesson-note{font-size:13px;color:var(--muted);margin-top:8px}.phasebar{margin-bottom:16px}@media(max-width:760px){.learn-grid{grid-template-columns:1fr}}