:root,[data-theme=academic]{color-scheme:light;--bg: #f3efe6;--surface: #fffdf8;--ink: #1c1915;--muted: #3f3a34;--line: #ddd4c4;--primary: #1a4332;--primary-hover: #123528;--primary-ink: #f7f4ee;--link: #1d6840;--danger: #8c2f2f;--danger-ink: #fffdf8;--warn: #6d4710;--warn-bg: #f6edd9;--accent: var(--primary);--accent-ink: var(--primary-ink);--space-1: .25rem;--space-2: .5rem;--space-3: .75rem;--space-4: 1rem;--space-5: 1.5rem;--space-6: 2.25rem;--shadow: none;--elevated-shadow: 0 16px 40px rgba(28, 25, 21, .1);--font-body: "Avenir Next", "Segoe UI", sans-serif;--font-heading: "Iowan Old Style", Palatino, "Palatino Linotype", Georgia, serif;--radius: 12px;--control-radius: 8px;--card-border: 1px solid var(--line);--card-pad: 1.05rem 1.15rem 1.15rem;--page-width: 960px;--page-gutter: 2.5rem;--page-y: 2.25rem;--page-bottom: 4.5rem;--stack: 1.5rem;--h1-size: 2.05rem;--h2-size: 1.25rem;--heading-weight: 600;--heading-spacing: -.02em;--button-weight: 600;--topbar: var(--surface);--topbar-border: 1px solid var(--line);--topbar-shadow: none;--later-bg: #f7f4ee;--field-bg: #fffdf8;--field-border: var(--line);--secondary-bg: transparent;--secondary-ink: var(--ink);--secondary-border: var(--line);--disabled-bg: #efeae2;--disabled-ink: #5c564f;--bar-height: .55rem;--radar-opacity: .18;--backdrop: rgba(28, 25, 21, .46);font-family:var(--font-body);line-height:1.5;color:var(--ink);background:var(--bg)}*{box-sizing:border-box}body{margin:0;min-height:100vh}h1,h2,h3,.brand{font-family:var(--font-heading);font-weight:var(--heading-weight);letter-spacing:var(--heading-spacing)}h1{font-size:var(--h1-size);margin:0}h2{font-size:var(--h2-size);margin:0}h3{font-size:1.15rem;margin:0}p{margin:0}a{color:var(--link)}a:hover{text-decoration:none}button,input,textarea{font:inherit}:focus-visible{outline:2px solid var(--primary);outline-offset:2px}.app{min-height:100vh}.topbar{display:flex;justify-content:space-between;align-items:center;gap:1rem;padding:.9rem 1.5rem;border-bottom:var(--topbar-border);background:var(--topbar);box-shadow:var(--topbar-shadow)}.brand{color:var(--ink);text-decoration:none;font-size:1.35rem}.topbar-user{display:flex;align-items:center;gap:.75rem;color:var(--muted)}.page{width:min(var(--page-width),calc(100% - var(--page-gutter)));margin:0 auto;padding:var(--page-y) 0 var(--page-bottom)}.page-head,.section-head{display:flex;justify-content:space-between;align-items:flex-start;gap:1rem;margin-bottom:1.25rem}.page-actions,.action-row,.modal-actions,.course-card-actions,.tree-actions{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem}.lead,.hint,.muted{color:var(--muted)}.lead{margin-top:.4rem;max-width:40rem}.eyebrow{margin:1rem 0 .2rem;color:var(--muted);font-size:.92rem}.back-link{margin-bottom:.8rem}.button{display:inline-flex;align-items:center;gap:.35rem;border:1px solid transparent;border-radius:var(--control-radius);padding:.5rem .9rem;background:var(--primary);color:var(--primary-ink);font-weight:var(--button-weight);cursor:pointer}.button:hover{background:var(--primary-hover)}.button:disabled{opacity:1;background:var(--disabled-bg);color:var(--disabled-ink);border-color:var(--line);cursor:not-allowed}.button-secondary{background:var(--secondary-bg);color:var(--secondary-ink);border-color:var(--secondary-border)}.button-secondary:hover{background:var(--disabled-bg)}.button-secondary:disabled{background:var(--disabled-bg);color:var(--disabled-ink);border-color:var(--line)}.button-danger{background:var(--danger);color:var(--danger-ink)}.button-danger:hover{background:var(--danger);filter:brightness(.92)}.button-danger:disabled{color:var(--danger);background:var(--disabled-bg);filter:none}.button-ghost{background:transparent;color:var(--link);border-color:transparent;padding-inline:.45rem;font-weight:500}.button-ghost:hover{background:transparent}.button-ghost.is-danger,.button-ghost.is-danger:hover{color:var(--danger);background:transparent;filter:none}.button-ghost:disabled{background:transparent;border-color:transparent}.course-list{display:grid;gap:.75rem}.course-card{display:flex;justify-content:space-between;gap:1rem;padding:var(--card-pad);background:var(--surface);border:var(--card-border);border-radius:var(--radius);box-shadow:var(--shadow)}.course-card p{margin-top:.35rem;color:var(--muted);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.panel{margin-top:var(--stack);padding:var(--card-pad);background:var(--surface);border:var(--card-border);border-radius:var(--radius);box-shadow:var(--shadow)}.later-section{background:var(--later-bg)}.later{color:var(--warn);background:var(--warn-bg);border-radius:999px;padding:.1rem .5rem;font-size:.82rem}.later-list{list-style:none;margin:var(--space-3) 0 0;padding:0;display:grid;gap:.55rem}.quiz-availability{display:grid;gap:.35rem;justify-items:start}.quiz-availability .hint{margin:0}.material-list{list-style:none;margin:var(--space-4) 0 0;padding:0;display:grid;gap:var(--space-3)}.material{display:grid;gap:var(--space-1);padding-top:var(--space-3);border-top:1px solid var(--line)}.material-name{font-weight:600}.material-meta{color:var(--muted);font-size:.92rem}.status-badge{display:inline-flex;align-items:center;border-radius:999px;padding:.05rem .5rem;font-size:.78rem;font-weight:600;background:var(--disabled-bg);color:var(--muted);border:1px solid var(--line)}.status-badge.status-processing{background:var(--warn-bg);color:var(--warn);border-color:transparent}.status-badge.status-ready{background:var(--surface);color:var(--primary);border-color:var(--primary)}.status-badge.status-failed{background:var(--surface);color:var(--danger);border-color:var(--danger)}.material-file{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}.source-citation{display:grid;gap:var(--space-1)}.source-view{display:grid;gap:var(--space-4)}.source-layout{display:grid;gap:var(--space-4);align-items:start}@media(min-width:800px){.source-layout{grid-template-columns:minmax(16rem,22rem) minmax(0,1fr)}}.source-passage{background:var(--warn-bg);border-radius:.6rem;padding:var(--space-3)}.source-passage h2{font-size:1rem}.source-text{white-space:pre-wrap;overflow:auto;max-height:70vh;margin:0;background:var(--surface);border:1px solid var(--line);border-radius:.6rem;padding:var(--space-3)}.source-passage mark,.source-text mark{background:#ffe08a;color:inherit}.pdf-view{display:grid;gap:var(--space-3)}.source-canvas{width:100%;height:auto;background:#fff;border:1px solid var(--line);border-radius:.4rem}.tree,.tree ul,.child-list{list-style:none;margin:0;padding:0}.tree ul{margin-left:.7rem;padding-left:.8rem;border-left:1px solid var(--line)}.tree-row{display:flex;align-items:center;gap:.35rem;padding:.25rem 0}.tree-name{font-weight:600}.tree-actions{margin-left:auto}.chevron,.chevron-spacer{width:1.6rem;height:1.6rem;flex:none}.chevron{border:none;background:transparent;color:var(--muted);cursor:pointer;border-radius:6px}.child-list{display:grid;gap:.35rem;margin-top:.6rem}.progress-empty,.leaf-progress,.mastery-bars{display:grid;gap:.45rem;margin-top:.8rem}.mastery-bars{list-style:none;margin:.8rem 0 0;padding:0}.mastery-bar-label{display:flex;justify-content:space-between;gap:1rem;font-weight:600}.mastery-track{height:var(--bar-height);border-radius:999px;background:var(--line);overflow:hidden}.mastery-fill{height:100%;background:var(--primary)}.mastery-score{font-size:1.35rem}.topic-progress{display:grid;gap:.75rem;margin:1rem 0 0;padding:0;list-style:none}.topic-progress li{display:grid;gap:.15rem}.leaf-progress{margin-top:.8rem;gap:1.15rem}.leaf-mastery{display:grid;gap:.35rem;max-width:28rem}.leaf-mastery .quiz-label{margin:0}.leaf-mastery .mastery-score{margin:0;font-size:2.5rem;line-height:1;font-weight:600}.leaf-heading{margin:0;font-weight:600}.concept-performance{display:grid;gap:.4rem}.concept-performance .progress-empty{margin-top:.15rem}.concept-performance .mastery-bars{margin-top:.2rem}.concept-values{list-style:none;margin:.15rem 0 0;padding:0;display:grid;gap:.35rem}.concept-values li{display:flex;justify-content:space-between;gap:1rem;align-items:baseline}.mastery-explain summary{width:fit-content;cursor:pointer;color:var(--primary)}.mastery-explain p,.mastery-explain li{color:var(--muted)}.mastery-explain ul{margin:.35rem 0 0;padding-left:1.1rem}.difficulty-rows,.recent-evidence{list-style:none;margin:.45rem 0 0;padding:0;display:grid;gap:.55rem}.difficulty-row{display:grid;grid-template-columns:5.5rem 3.4rem 3.2rem minmax(5rem,1fr);align-items:center;gap:.65rem}.recent-evidence li{display:flex;gap:.85rem;align-items:baseline}.evidence-mark{width:1rem;font-weight:700}.radar{margin:.15rem 0 0}.radar-plot{overflow:visible;padding:.15rem clamp(.5rem,4vw,1rem) .25rem}.radar svg{width:min(100%,32rem);height:auto;display:block;margin:0 auto;overflow:visible}.radar-ring,.radar-axis{fill:none;stroke:var(--line);stroke-width:1}.radar-area{fill:var(--primary);fill-opacity:var(--radar-opacity);stroke:var(--primary);stroke-width:2}.radar-point{fill:var(--primary)}.radar-label{fill:var(--ink);font-size:13px;font-family:var(--font-body)}.mastery-table{width:100%;border-collapse:collapse;margin-top:.5rem}.mastery-table caption{text-align:left;font-weight:600;margin-bottom:.35rem}.mastery-table th,.mastery-table td{text-align:left;padding:.35rem .4rem;border-bottom:1px solid var(--line)}.mastery-table td:last-child{text-align:right;color:var(--muted)}.crumbs{display:flex;flex-wrap:wrap;gap:.35rem;list-style:none;margin:0 0 .5rem;padding:0;color:var(--muted)}.crumbs li{display:flex;gap:.35rem}.crumbs [aria-current=page]{color:var(--ink)}.state{padding:2rem 0;color:var(--muted)}.state h1,.state h2{color:var(--ink);margin-bottom:.4rem}.state-error p{margin-bottom:.8rem}.auth-page{min-height:100vh;display:grid;place-items:center;padding:1.5rem}.auth-card{width:min(26rem,100%);display:grid;gap:.85rem;padding:1.5rem;background:var(--surface);border:var(--card-border);border-radius:var(--radius);box-shadow:var(--elevated-shadow)}.auth-card .button{width:100%}.auth-cta{margin:0;font-size:1.05rem;font-weight:600;color:var(--ink)}.auth-cta a{color:var(--link)}.auth-switch{color:var(--muted)}.auth-switch .link-button{border:0;padding:0;background:none;color:var(--link);cursor:pointer;font:inherit}.auth-switch .link-button:disabled{color:var(--muted);cursor:default}.form-notice{color:var(--muted)}.verified-email{display:grid;gap:.3rem;color:var(--ink)}.verified-email span{font-size:.92rem}.field{display:grid;gap:.3rem}.field label{font-size:.92rem}.field input,.field textarea{width:100%;padding:.55rem .65rem;border:1px solid var(--field-border);border-radius:var(--control-radius);background:var(--field-bg);color:var(--ink)}.field-error,.form-error{color:var(--danger)}.banner{margin:.75rem 1.5rem 0}.modal{border:none;padding:0;background:transparent;max-width:calc(100% - 2rem)}.modal::backdrop{background:var(--backdrop)}.modal-card{width:min(32rem,100%);padding:1.2rem;background:var(--surface);border-radius:var(--radius);box-shadow:var(--elevated-shadow)}.modal-head{display:flex;justify-content:space-between;align-items:center;gap:1rem;margin-bottom:.8rem}.modal-card form{display:grid;gap:.8rem}.modal-actions{justify-content:flex-end}.icon-button{border:none;background:transparent;color:var(--muted);cursor:pointer}@media(max-width:700px){.page-head,.course-card,.topbar{flex-direction:column;align-items:stretch}.tree-row{flex-wrap:wrap}.tree-actions{margin-left:1.9rem}}[data-theme=saas]{--bg: #f4f6f8;--surface: #ffffff;--ink: #12151c;--muted: #4b5565;--line: #e4e7ee;--accent: #1d4ed8;--accent-ink: #ffffff;--primary: #1d4ed8;--primary-hover: #1e40af;--primary-ink: #ffffff;--link: #1d4ed8;--danger: #b42318;--warn: #92400e;--warn-bg: #fef3c7;--shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 8px 20px rgba(16, 24, 40, .05);--elevated-shadow: 0 16px 40px rgba(16, 24, 40, .12);--font-body: "Segoe UI", "Helvetica Neue", "Avenir Next", sans-serif;--font-heading: "Segoe UI", "Helvetica Neue", "Avenir Next", sans-serif;--radius: 8px;--control-radius: 6px;--card-pad: .85rem 1rem;--page-width: 1040px;--page-y: 1.5rem;--stack: 1rem;--h1-size: 1.6rem;--h2-size: 1.05rem;--heading-weight: 600;--heading-spacing: -.015em;--topbar: #ffffff;--topbar-border: 1px solid var(--line);--topbar-shadow: 0 1px 0 rgba(16, 24, 40, .04);--later-bg: #ffffff;--field-bg: #ffffff;--secondary-bg: #ffffff;--secondary-ink: var(--ink);--secondary-border: #cfd5e0;--disabled-bg: #f3f5f8;--bar-height: .4rem;--radar-opacity: .14;--backdrop: rgba(16, 24, 40, .45)}[data-theme=minimal]{--bg: #fafafa;--surface: #ffffff;--ink: #1a1a1a;--muted: #5c5c5c;--line: #ececec;--accent: #1c1c1c;--accent-ink: #fafafa;--primary: #1c1c1c;--primary-hover: #000000;--primary-ink: #fafafa;--link: #1c1c1c;--danger: #8f2d2d;--warn: #6b5e48;--warn-bg: transparent;--shadow: none;--elevated-shadow: none;--font-body: "Helvetica Neue", "Segoe UI", sans-serif;--font-heading: "Helvetica Neue", "Segoe UI", sans-serif;--radius: 0;--control-radius: 0;--card-border: none;--card-pad: .25rem 0 1.5rem;--page-width: 720px;--page-gutter: 4rem;--page-y: 4rem;--stack: 2.75rem;--h1-size: 2.75rem;--h2-size: 1.35rem;--heading-weight: 500;--heading-spacing: -.03em;--button-weight: 500;--topbar: transparent;--topbar-border: none;--topbar-shadow: none;--later-bg: transparent;--field-bg: transparent;--field-border: #d4d4d4;--secondary-bg: transparent;--secondary-ink: var(--ink);--secondary-border: var(--ink);--disabled-bg: transparent;--bar-height: 2px;--radar-opacity: .08;--backdrop: rgba(0, 0, 0, .35)}[data-theme=friendly]{--bg: #f4f7fb;--surface: #ffffff;--ink: #1b2430;--muted: #3e4c5e;--line: #d5deea;--accent: #0f6e6b;--accent-ink: #f4fffd;--primary: #0f6e6b;--primary-hover: #0b5552;--primary-ink: #f4fffd;--link: #0f6e6b;--danger: #9f2d3a;--warn: #8a5a12;--warn-bg: #fff4df;--shadow: 0 8px 22px rgba(27, 45, 70, .07);--elevated-shadow: 0 16px 36px rgba(27, 45, 70, .12);--font-body: "Avenir Next", "Trebuchet MS", "Segoe UI", sans-serif;--font-heading: "Avenir Next", "Trebuchet MS", "Segoe UI", sans-serif;--radius: 14px;--control-radius: 10px;--card-pad: 1.15rem 1.2rem 1.25rem;--page-y: 1.75rem;--stack: 1.15rem;--h1-size: 2.1rem;--h2-size: 1.2rem;--heading-weight: 700;--topbar: #ffffff;--topbar-border: none;--topbar-shadow: 0 1px 0 var(--line);--later-bg: #ffffff;--field-bg: #ffffff;--secondary-bg: #ffffff;--secondary-ink: var(--accent);--secondary-border: #b7ddd9;--disabled-bg: #f7f9fc;--bar-height: .85rem;--radar-opacity: .28;--tone-materials: #e7f3ec;--tone-quiz: #e7eefb;--tone-revision: #f8f0e4;--tone-flashcards: #f3eaf6;--tone-practice: #e5f4f2;--tone-progress: #ffffff}.section-icon{display:none}[data-theme=friendly] .section-icon{display:inline-block;width:1.05rem;height:1.05rem;margin-right:.4rem;vertical-align:-.15em;flex:none}[data-theme=friendly] .tone-materials{background:var(--tone-materials)}[data-theme=friendly] .tone-progress{background:var(--tone-progress);border-top:3px solid var(--accent)}[data-theme=friendly] .tone-quiz{background:var(--tone-quiz)}[data-theme=friendly] .tone-revision{background:var(--tone-revision)}[data-theme=friendly] .tone-flashcards{background:var(--tone-flashcards)}[data-theme=friendly] .tone-practice{background:var(--tone-practice)}[data-theme=friendly] .later-list .action-row{border-radius:var(--radius);padding:.45rem .6rem}[data-theme=friendly] .later-list .button:disabled,[data-theme=friendly] .tone-materials .button:disabled{background:transparent;border-color:transparent;color:var(--ink)}[data-theme=minimal] .later{background:transparent;padding:0;border-radius:0}[data-theme=minimal] .panel,[data-theme=minimal] .course-card{border-bottom:1px solid var(--line)}[data-theme=minimal] .auth-card{border:1px solid var(--line);padding:2rem .25rem}[data-theme=minimal] .topbar{padding-top:1.5rem}[data-theme=saas] .brand{font-size:1.05rem;letter-spacing:-.02em}[data-theme=saas] .button{letter-spacing:0}[data-theme=saas] .course-list{gap:.55rem}.design-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(14rem,1fr));gap:1rem;margin-top:1.5rem}.design-card p{margin-top:.4rem;color:var(--muted)}.design-card .page-actions{margin-top:.9rem}html.theme-lab{--page-bottom: 6.5rem}.theme-switcher{position:fixed;z-index:30;left:50%;bottom:1rem;transform:translate(-50%);display:flex;align-items:center;gap:.15rem;max-width:calc(100% - 1.5rem);padding:.3rem;background:var(--surface);color:var(--ink);border:1px solid var(--line);border-radius:999px;box-shadow:var(--elevated-shadow)}.theme-switcher button,.theme-switcher a{border:0;background:transparent;color:var(--ink);text-decoration:none;border-radius:999px;padding:.35rem .7rem;font:inherit;font-size:.85rem;cursor:pointer}.theme-switcher a{border-left:1px solid var(--line);border-radius:0 999px 999px 0}.theme-switcher button.is-active{background:var(--accent);color:var(--accent-ink)}.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.quiz-take{display:grid;gap:1.25rem;max-width:42rem}.quiz-meta{display:flex;justify-content:space-between;gap:1rem;margin-top:.75rem;color:var(--muted)}.quiz-prompt{font-family:var(--font-body);font-size:1.2rem;font-weight:600;letter-spacing:0;line-height:1.45}.quiz-progress{height:.45rem;margin-top:.7rem;background:var(--line);border-radius:999px;overflow:hidden}.quiz-progress>span{display:block;height:100%;background:var(--primary)}.choice-list{display:grid;gap:.6rem;margin:0;padding:0;border:0}.choice-card{display:flex;align-items:flex-start;gap:.75rem;padding:.85rem 1rem;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);cursor:pointer}.choice-card.is-selected{border-color:var(--primary);background:#e7f0ea;box-shadow:inset 3px 0 0 var(--primary)}.choice-card.is-correct{border-color:#1d6840;background:#e7f0ea;box-shadow:inset 3px 0 #1d6840}.choice-card.is-incorrect{border-color:var(--danger);background:#f8ecec;box-shadow:inset 3px 0 0 var(--danger)}.choice-mark{margin-left:auto;color:var(--ink);font-size:.85rem;font-weight:600;white-space:nowrap}.choice-card.is-correct .choice-mark{color:#14532d}.choice-card.is-incorrect .choice-mark{color:var(--danger)}.choice-card input{accent-color:var(--primary);margin-top:.25rem}.choice-card.is-correct input{accent-color:#1d6840}.choice-card.is-incorrect input{accent-color:var(--danger)}.choice-list:disabled .choice-card{cursor:default}.feedback-correct,.feedback-incorrect{display:grid;gap:.45rem;padding:.9rem 1rem;border-radius:var(--radius)}.feedback-correct{background:#e7f0ea;border:1px solid var(--primary)}.feedback-incorrect{background:#f8ecec;border:1px solid var(--danger)}.quiz-label{font-weight:600}.quiz-score{font-family:var(--font-heading);font-size:1.8rem}.quiz-source{display:flex;flex-wrap:wrap;gap:.35rem .75rem}.topic-results{list-style:none;margin:.75rem 0 0;padding:0;display:grid;gap:.45rem}.topic-results li{display:flex;justify-content:space-between;gap:1rem;padding:.55rem 0;border-bottom:1px solid var(--line)}