:root{color-scheme:dark;--bg:#11100f;--panel:#1b1916;--paper:#24211d;--raised:#2c2822;--ink:#f4ead8;--muted:#b8aa96;--line:#443b31;--gold:#c89b54;--amber:#e4b76c;--good:#71bd8c;--bad:#e07b70;--soft:#33291d;--shadow:0 16px 42px #0007}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(circle at 80% 0,#271e14 0,transparent 35%),var(--bg);color:var(--ink);font:16px/1.55 Inter,system-ui,sans-serif}.shell{min-height:100vh;display:grid;grid-template-columns:280px 1fr}aside{position:sticky;top:0;height:100vh;background:#171411;border-right:1px solid var(--line);padding:25px 18px;display:flex;flex-direction:column}.brand{padding:4px 10px 22px;border-bottom:1px solid var(--line)}.brand small,.eyebrow{color:var(--gold);letter-spacing:.14em;font-weight:800;font-size:.7rem}.brand h1,h1,h2,h3{font-family:Georgia,serif}.brand h1{font-size:1.25rem;line-height:1.25;margin:.35rem 0 0}nav{display:grid;gap:3px;padding-top:14px}nav a{color:#ddcfbb;text-decoration:none;padding:10px 12px;border-radius:9px}nav a:hover{background:var(--raised);color:#fff}aside footer{margin-top:auto;color:#82786a;font-size:.78rem;padding:14px 10px;border-top:1px solid var(--line)}main{min-width:0}header{position:sticky;top:0;z-index:4;background:#11100ee8;backdrop-filter:blur(10px);border-bottom:1px solid var(--line);padding:13px 30px;font-weight:700}.menu{display:none}.content{max-width:1180px;margin:auto;padding:38px 35px 90px}h1{font-size:clamp(2rem,4vw,3.3rem);line-height:1.12;margin:.25em 0}h2{font-size:1.5rem;margin:2rem 0 .7rem}h3{margin:1.3rem 0 .5rem}.muted,small{color:var(--muted)}a{color:var(--amber)}button,.button{font:inherit;border:1px solid var(--gold);background:var(--gold);color:#17110a;font-weight:800;border-radius:9px;padding:9px 14px;text-decoration:none;cursor:pointer;display:inline-block}.secondary{background:transparent;color:var(--ink);border-color:var(--line)}.danger{background:#8d3f38;border-color:#b85950;color:#fff}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:13px}.card,.question,.callout{background:linear-gradient(145deg,var(--paper),#201d19);border:1px solid var(--line);border-radius:14px;padding:18px;box-shadow:0 3px 16px #0002}.metric strong{display:block;font:700 1.8rem Georgia,serif;color:#fff}.metric span{color:var(--muted)}.hero{padding-bottom:22px}.recommended{border-left:4px solid var(--gold);background:var(--soft);padding:18px;border-radius:0 12px 12px 0}.module-card{display:block;color:var(--ink);text-decoration:none}.module-card:hover{border-color:var(--gold);transform:translateY(-1px)}.progress{height:8px;background:#100f0d;border-radius:9px;overflow:hidden}.progress i{display:block;height:100%;background:var(--gold)}.lesson{max-width:900px}.lesson table,table{width:100%;border-collapse:collapse;background:var(--panel)}th,td{padding:10px;border:1px solid var(--line);text-align:left;vertical-align:top}th{background:var(--soft);color:var(--amber)}.flash-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:14px}.flashcard{min-height:220px;perspective:900px;cursor:pointer}.flash-inner{display:grid;height:100%;min-height:220px;transform-style:preserve-3d;transition:.35s}.flashcard.flipped .flash-inner{transform:rotateY(180deg)}.flash-face{grid-area:1/1;backface-visibility:hidden;background:var(--paper);border:1px solid var(--line);border-radius:13px;padding:20px;display:flex;flex-direction:column;justify-content:center}.flash-back{transform:rotateY(180deg);background:var(--soft)}.flash-actions{display:flex;gap:6px;flex-wrap:wrap;margin-top:8px}.flash-actions button{font-size:.8rem;padding:6px 9px}.question{margin:14px 0}.options{display:grid;gap:8px}.option{display:flex;gap:10px;border:1px solid var(--line);padding:11px;border-radius:9px;cursor:pointer}.option:hover{background:var(--raised)}.option.correct{border-color:var(--good);background:#163121}.option.wrong{border-color:var(--bad);background:#3a1e1c}.result-good{color:var(--good)}.result-bad{color:var(--bad)}.timer{position:sticky;top:52px;z-index:3;background:#291d0d;border:1px solid var(--gold);padding:10px 14px;border-radius:10px;font-weight:900}.navigator{display:flex;flex-wrap:wrap;gap:5px;margin:14px 0}.navigator a{display:grid;place-items:center;width:34px;height:34px;background:var(--paper);border:1px solid var(--line);border-radius:6px;text-decoration:none;color:var(--ink)}.navigator a.answered{background:#29422e;border-color:var(--good)}.notice{background:#25351f;border:1px solid #496641;padding:12px 15px;border-radius:9px;margin-bottom:18px}.pill{display:inline-block;border:1px solid var(--line);border-radius:20px;padding:3px 8px;color:var(--muted);font-size:.78rem}.bar{display:flex;height:8px;background:#3a1e1c;border-radius:8px;overflow:hidden}.bar i{background:var(--good)}form.inline{display:inline}.form-row{margin:12px 0}select,input[type=text]{background:var(--paper);color:var(--ink);border:1px solid var(--line);padding:9px;border-radius:8px}.actions{display:flex;gap:9px;align-items:center;flex-wrap:wrap;margin:18px 0}.review-note{border-top:1px solid var(--line);margin-top:12px;padding-top:12px}.trend-up{color:var(--good)}.trend-down{color:var(--bad)}@media(max-width:760px){.shell{display:block}aside{position:fixed;z-index:10;width:280px;transform:translateX(-100%);transition:.2s}aside.open{transform:none}.menu{display:inline-block;background:transparent;color:var(--ink);border:0;padding:0 15px 0 0}.content{padding:25px 16px 70px}header{padding:13px 16px}.grid,.flash-grid{grid-template-columns:1fr}table{font-size:.85rem}.table-wrap{overflow:auto}}
.module-grid{grid-template-columns:repeat(auto-fit,minmax(285px,1fr))}.module-card{display:flex;flex-direction:column;min-height:315px}.module-card h3{font-size:1.35rem;min-height:3.2em}.module-stats{display:grid;grid-template-columns:repeat(2,1fr);gap:7px 12px;color:var(--muted);font-size:.82rem}.module-stats strong{color:var(--ink)}.module-stats .know strong{color:var(--good)}.module-stats .learning strong{color:var(--amber)}.module-stats .again strong{color:var(--bad)}.confidence-bar{display:flex;height:9px;background:#100f0d;border-radius:9px;overflow:hidden;margin:12px 0 18px}.confidence-bar i{display:block;height:100%}.confidence-bar .know{background:var(--good)}.confidence-bar .learning{background:var(--amber)}.confidence-bar .again{background:var(--bad)}.quiz-summary{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;border-top:1px solid var(--line);padding-top:14px;margin-top:auto}.quiz-summary span{display:flex;flex-direction:column}.quiz-summary small{font-size:.7rem}.quiz-summary strong{font-size:1.1rem;color:var(--ink)}.module-overview{grid-template-columns:repeat(3,minmax(150px,1fr));margin-top:22px}.module-overview .card{padding:14px}.module-overview .metric strong{font-size:1.45rem}@media(max-width:760px){.module-grid,.module-overview{grid-template-columns:1fr}.module-card h3{min-height:0}}
/* Focused one-card Study Drill experience */
.study-card{max-width:780px;margin:1.5rem auto}.study-progress{max-width:780px;margin:0 auto;display:flex;justify-content:space-between;gap:1rem;color:var(--muted)}.drill-option{display:block;width:100%;text-align:left;margin:.65rem 0;background:var(--raised);color:var(--ink);border:1px solid var(--line);cursor:pointer}.drill-option:hover{border-color:var(--gold);transform:translateY(-1px)}.drill-builder .form-row{display:flex;flex-wrap:wrap;gap:12px;align-items:end}.drill-builder label{display:grid;gap:5px}.study-card .review-note{margin-top:1.25rem}
.review-filter{display:inline-flex;align-items:center;gap:8px;background:var(--soft);border:1px solid var(--line);border-radius:9px;padding:9px 12px;cursor:pointer;font-weight:700}.review-filter input{accent-color:var(--gold)}

/* Account and administration forms */
.auth-card{max-width:480px;padding:28px}.auth-card label,.card>label{display:grid;gap:6px;margin-bottom:16px}.auth-card .actions{margin-bottom:0}.card input:not([type]),.card input[type="text"],.card input[type="email"],.card input[type="password"],.card select{display:block;width:100%;min-width:0;background:var(--paper);color:var(--ink);border:1px solid var(--line);padding:10px 11px;border-radius:8px;font:inherit}.card input:focus,.card select:focus{outline:2px solid color-mix(in srgb,var(--gold) 65%,transparent);outline-offset:1px;border-color:var(--gold)}.card .form-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px;align-items:end}.card .form-row label{display:grid;gap:6px;min-width:0}.link-button{border:0;background:transparent;color:var(--amber);padding:5px 0;font-weight:700}.link-button:hover{color:var(--ink)}

@media(max-width:760px){.auth-card{max-width:none;padding:22px}.card .form-row{grid-template-columns:1fr}}

/* Per-user appearance themes */
:root[data-theme="oak"]{--bg:#100c0a;--panel:#19120f;--paper:#211814;--raised:#2b1f19;--ink:#eee6dc;--muted:#9b8b7c;--line:#3b2b23;--gold:#c47a43;--amber:#78947a;--soft:#2c2019;--theme-ambient:#3a2519;--theme-sidebar:#15100d;--theme-header:#100c0ae8;--theme-card-end:#18110e}
:root[data-theme="oxblood"]{--bg:#100b0c;--panel:#1b1113;--paper:#241619;--raised:#301c20;--ink:#eee5df;--muted:#998489;--line:#40272c;--gold:#c29a58;--amber:#b95860;--soft:#301b20;--theme-ambient:#40191f;--theme-sidebar:#160d0f;--theme-header:#100b0ce8;--theme-card-end:#190f11}
:root[data-theme="forest"]{--bg:#0b100d;--panel:#111a15;--paper:#17221b;--raised:#203027;--ink:#e8ece5;--muted:#8f9c92;--line:#293c30;--gold:#c5864e;--amber:#6f9a7c;--soft:#1d2c22;--theme-ambient:#193426;--theme-sidebar:#0e1511;--theme-header:#0b100de8;--theme-card-end:#101812}
:root[data-theme="graphite"]{--bg:#0e0e0f;--panel:#171719;--paper:#202023;--raised:#29292d;--ink:#eeeeec;--muted:#929095;--line:#3a3a3f;--gold:#d56f3e;--amber:#aaa49c;--soft:#27272a;--theme-ambient:#34231d;--theme-sidebar:#131314;--theme-header:#0e0e0fe8;--theme-card-end:#18181a}

body{background:radial-gradient(circle at 80% 0,var(--theme-ambient) 0,transparent 35%),var(--bg)}
aside{background:var(--theme-sidebar)}
header{background:var(--theme-header)}
.card,.question,.callout{background:linear-gradient(145deg,var(--paper),var(--theme-card-end))}

/* Profile and user-management settings */
.profile-form{max-width:720px}
.user-list{display:grid;gap:12px}
.user-accordion{padding:0;overflow:hidden}
.user-accordion>summary{display:flex;justify-content:space-between;align-items:center;gap:18px;padding:18px;cursor:pointer;list-style:none}
.user-accordion>summary::-webkit-details-marker{display:none}
.user-accordion>summary::after{content:"+";flex:0 0 auto;color:var(--gold);font-size:1.3rem;font-weight:700;line-height:1}
.user-accordion[open]>summary::after{content:"−"}
.user-accordion>summary:hover{background:var(--raised)}
.user-accordion>summary:focus-visible{outline:2px solid var(--gold);outline-offset:-2px}
.user-identity{display:grid;min-width:0}
.user-identity small{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.user-meta{display:flex;gap:7px;align-items:center;margin-left:auto}
.user-settings{padding:18px;border-top:1px solid var(--line)}
.user-settings .actions{margin-bottom:0}
.user-settings>form+form{margin-top:12px;padding-top:16px;border-top:1px solid var(--line)}

@media(max-width:760px){.user-accordion>summary{align-items:flex-start}.user-meta{display:none}.user-settings{padding:15px}}