:root{
  --bg:#F4F6F7; --surface:#FFFFFF; --surface2:#EDF1F3; --ink:#16232E; --muted:#5B6B77; --line:#DCE3E7;
  --accent:#0B666D; --accent-hover:#095257; --accent-ink:#FFFFFF; --accent-soft:#E3EEEF; --accent-soft-ink:#0B4C52;
  --amber:#A96A1E; --amber-soft:#F4E8D7; --green:#2F7D4F; --green-soft:#E1EFE6; --red:#B23A32; --red-soft:#F6E2E0;
  --shadow:0 1px 2px rgba(22,35,46,.06),0 4px 14px rgba(22,35,46,.05);
  --focus:#0B666D;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --bg:#0E161C; --surface:#16212A; --surface2:#1C2933; --ink:#E7EEF3; --muted:#92A3AF; --line:#27343E;
    --accent:#4FB3BA; --accent-hover:#6BC4CA; --accent-ink:#08272A; --accent-soft:#123239; --accent-soft-ink:#9BD4D8;
    --amber:#D9A05B; --amber-soft:#3A2E1B; --green:#6FBE93; --green-soft:#1C3327; --red:#E08078; --red-soft:#3B211F;
    --shadow:0 1px 2px rgba(0,0,0,.3),0 4px 14px rgba(0,0,0,.25);
    --focus:#4FB3BA;
  }
}
:root[data-theme="dark"]{
  --bg:#0E161C; --surface:#16212A; --surface2:#1C2933; --ink:#E7EEF3; --muted:#92A3AF; --line:#27343E;
  --accent:#4FB3BA; --accent-hover:#6BC4CA; --accent-ink:#08272A; --accent-soft:#123239; --accent-soft-ink:#9BD4D8;
  --amber:#D9A05B; --amber-soft:#3A2E1B; --green:#6FBE93; --green-soft:#1C3327; --red:#E08078; --red-soft:#3B211F;
  --shadow:0 1px 2px rgba(0,0,0,.3),0 4px 14px rgba(0,0,0,.25);
  --focus:#4FB3BA;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{background:var(--bg);color:var(--ink);font-family:"Source Sans 3",-apple-system,"Segoe UI",Roboto,sans-serif;font-size:16px;line-height:1.55;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4{font-family:"Archivo","Source Sans 3",sans-serif;text-wrap:balance;line-height:1.2;margin:0 0 .5em}
h1{font-size:1.7rem;font-weight:800;letter-spacing:-.01em}
h2{font-size:1.3rem;font-weight:700}
h3{font-size:1.05rem;font-weight:700}
p{margin:.4em 0 .8em}
a{color:var(--accent)}
button{font:inherit;cursor:pointer}
:focus-visible{outline:2px solid var(--focus);outline-offset:2px}
@media (prefers-reduced-motion: reduce){*,*::before,*::after{animation:none!important;transition:none!important}}

.app{display:flex;min-height:100vh}
.sidebar{width:250px;flex-shrink:0;background:var(--surface);border-right:1px solid var(--line);padding:20px 14px;display:flex;flex-direction:column;gap:4px;position:sticky;top:0;height:100vh;overflow-y:auto}
.brand{display:flex;align-items:center;gap:10px;padding:4px 8px 16px}
.brand-mark{width:38px;height:38px;border-radius:9px;background:var(--accent);color:var(--accent-ink);display:flex;align-items:center;justify-content:center;font-family:"Archivo";font-weight:800;font-size:.8rem;letter-spacing:-.02em}
.brand-name{font-family:"Archivo";font-weight:800;font-size:1.05rem;line-height:1.15}
.brand-sub{font-size:.72rem;color:var(--muted);font-family:"IBM Plex Mono",monospace}
.nav-label{font-family:"IBM Plex Mono",monospace;font-size:.68rem;text-transform:uppercase;letter-spacing:.09em;color:var(--muted);padding:14px 10px 6px}
.nav-item{display:flex;align-items:center;gap:10px;padding:9px 10px;border-radius:8px;border:none;background:none;color:var(--ink);text-align:left;width:100%;font-size:.95rem;text-decoration:none}
.nav-item:hover{background:var(--surface2)}
.nav-item.active{background:var(--accent-soft);color:var(--accent-soft-ink);font-weight:600}
.nav-item .ic{width:20px;text-align:center;flex-shrink:0}
.nav-progress{margin-top:auto;padding:12px 10px;border-top:1px solid var(--line);font-size:.8rem;color:var(--muted)}
.nav-progress .bar{margin-top:6px}

.topbar{display:none;position:sticky;top:0;z-index:40;background:var(--surface);border-bottom:1px solid var(--line);padding:10px 14px;align-items:center;gap:12px}
.topbar .brand{padding:0}
.menu-btn{background:none;border:1px solid var(--line);border-radius:8px;padding:6px 12px;color:var(--ink);font-size:1.05rem}
.main{flex:1;min-width:0;padding:28px clamp(16px,4vw,44px) 64px;max-width:980px}
.overlay{display:none;position:fixed;inset:0;background:rgba(10,18,24,.45);z-index:49}

@media (max-width:900px){
  .sidebar{position:fixed;left:0;top:0;z-index:50;transform:translateX(-102%);transition:transform .2s ease;box-shadow:var(--shadow)}
  .sidebar.open{transform:none}
  .overlay.show{display:block}
  .topbar{display:flex}
  .main{padding:20px 14px 64px}
}

.eyebrow{font-family:"IBM Plex Mono",monospace;font-size:.72rem;text-transform:uppercase;letter-spacing:.1em;color:var(--accent);margin-bottom:6px}
.lead{color:var(--muted);max-width:62ch}
.card{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px 20px;box-shadow:var(--shadow)}
.grid{display:grid;gap:14px}
.grid.cols2{grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}
.grid.cols3{grid-template-columns:repeat(auto-fit,minmax(200px,1fr))}
.row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.spacer{height:18px}

.btn{display:inline-flex;align-items:center;gap:8px;border-radius:9px;padding:9px 16px;border:1px solid var(--line);background:var(--surface);color:var(--ink);font-weight:600;font-size:.93rem;text-decoration:none}
.btn:hover{background:var(--surface2)}
.btn-primary{background:var(--accent);border-color:var(--accent);color:var(--accent-ink)}
.btn-primary:hover{background:var(--accent-hover);border-color:var(--accent-hover)}
.btn-ghost{border-color:transparent;background:none;color:var(--accent)}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.btn-sm{padding:6px 12px;font-size:.85rem}

.pill{display:inline-flex;align-items:center;border-radius:99px;padding:2px 10px;font-size:.72rem;font-weight:600;letter-spacing:.03em;font-family:"IBM Plex Mono",monospace}
.pill-muss{background:var(--accent-soft);color:var(--accent-soft-ink)}
.pill-soll{background:var(--amber-soft);color:var(--amber)}
.pill-neu{background:var(--red-soft);color:var(--red)}
.pill-ok{background:var(--green-soft);color:var(--green)}
.pill-cat{background:var(--surface2);color:var(--muted);font-family:"Source Sans 3",sans-serif;font-weight:600}
.mono{font-family:"IBM Plex Mono",monospace}
.num{font-variant-numeric:tabular-nums;font-family:"IBM Plex Mono",monospace}

.bar{height:8px;border-radius:99px;background:var(--surface2);overflow:hidden}
.bar>span{display:block;height:100%;border-radius:99px;background:var(--accent);transition:width .3s ease}
.bar.green>span{background:var(--green)}
.bar.amber>span{background:var(--amber)}

.stat{padding:14px 16px}
.stat .v{font-family:"Archivo";font-weight:800;font-size:1.7rem;line-height:1.1;font-variant-numeric:tabular-nums}
.stat .l{font-size:.8rem;color:var(--muted);margin-top:2px}

.req{border:1px solid var(--line);border-radius:11px;padding:14px 16px;background:var(--surface);margin-bottom:12px}
.req-head{display:flex;gap:10px;align-items:baseline;flex-wrap:wrap;margin-bottom:6px}
.req-id{font-family:"IBM Plex Mono",monospace;font-size:.78rem;font-weight:600;color:var(--accent);white-space:nowrap}
.req-title{font-family:"Archivo";font-weight:700;font-size:.98rem;flex:1;min-width:200px}
.req-text{margin:4px 0 0;font-size:.94rem}
.req-hint{margin-top:8px;padding:8px 12px;border-left:3px solid var(--accent-soft);background:var(--surface2);border-radius:0 8px 8px 0;font-size:.87rem;color:var(--muted)}
.req-hint b{color:var(--ink)}

.lesson-body{max-width:70ch}
.lesson-body table{border-collapse:collapse;width:100%;font-size:.9rem;margin:10px 0}
.lesson-body th,.lesson-body td{border:1px solid var(--line);padding:7px 10px;text-align:left;vertical-align:top}
.lesson-body th{background:var(--surface2);font-family:"Archivo";font-weight:700;font-size:.82rem}
.lesson-body ul,.lesson-body ol{padding-left:22px;margin:.4em 0 .9em}
.lesson-body li{margin-bottom:4px}
.table-wrap{overflow-x:auto}
.callout{border:1px solid var(--line);border-left:4px solid var(--accent);border-radius:0 10px 10px 0;background:var(--surface);padding:12px 16px;margin:14px 0;font-size:.93rem}
.callout.warn{border-left-color:var(--amber)}
.callout .callout-t{font-family:"Archivo";font-weight:700;font-size:.85rem;margin-bottom:3px}
.merk{background:var(--accent-soft);color:var(--accent-soft-ink);border-radius:10px;padding:12px 16px;margin:14px 0;font-size:.93rem}
.merk b{font-family:"Archivo"}

.quiz-q{font-family:"Archivo";font-weight:700;font-size:1.08rem;margin-bottom:14px}
.opt{display:flex;gap:12px;align-items:flex-start;width:100%;text-align:left;background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:12px 14px;margin-bottom:9px;color:var(--ink);font-size:.95rem}
.opt:hover{border-color:var(--accent)}
.opt .marker{flex-shrink:0;width:26px;height:26px;border-radius:7px;border:1.5px solid var(--line);display:flex;align-items:center;justify-content:center;font-family:"IBM Plex Mono",monospace;font-size:.78rem;font-weight:600}
.opt.sel{border-color:var(--accent);background:var(--accent-soft)}
.opt.sel .marker{border-color:var(--accent);background:var(--accent);color:var(--accent-ink)}
.opt.correct{border-color:var(--green);background:var(--green-soft)}
.opt.correct .marker{border-color:var(--green);background:var(--green);color:#fff}
.opt.wrong{border-color:var(--red);background:var(--red-soft)}
.opt.wrong .marker{border-color:var(--red);background:var(--red);color:#fff}
.opt[disabled]{cursor:default}
.expl{border-radius:10px;padding:12px 16px;margin:10px 0;font-size:.92rem}
.expl.ok{background:var(--green-soft);border:1px solid var(--green)}
.expl.no{background:var(--red-soft);border:1px solid var(--red)}
.expl .ref{display:block;margin-top:6px;font-family:"IBM Plex Mono",monospace;font-size:.75rem;color:var(--muted)}

.flashcard{perspective:1200px;max-width:560px;margin:0 auto}
.fc-inner{position:relative;min-height:250px;transform-style:preserve-3d;transition:transform .45s ease;cursor:pointer}
.fc-inner.flipped{transform:rotateY(180deg)}
.fc-face{position:absolute;inset:0;backface-visibility:hidden;border-radius:14px;border:1px solid var(--line);background:var(--surface);box-shadow:var(--shadow);padding:26px;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center}
.fc-face.back{transform:rotateY(180deg);background:var(--surface)}
.fc-face .fc-label{position:absolute;top:14px;left:16px;font-family:"IBM Plex Mono",monospace;font-size:.7rem;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.fc-face .fc-mod{position:absolute;top:14px;right:16px}
.fc-q{font-family:"Archivo";font-weight:700;font-size:1.12rem}
.fc-a{font-size:.98rem;max-width:46ch}

.timerbar{position:sticky;top:0;z-index:30;background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:10px 16px;display:flex;align-items:center;gap:14px;margin-bottom:16px;box-shadow:var(--shadow)}
.timerbar .time{font-family:"IBM Plex Mono",monospace;font-weight:600;font-size:1.05rem}
.timerbar .time.low{color:var(--red)}
.qnav{display:flex;flex-wrap:wrap;gap:6px;margin:12px 0}
.qnav button{width:34px;height:34px;border-radius:8px;border:1px solid var(--line);background:var(--surface);font-family:"IBM Plex Mono",monospace;font-size:.78rem;color:var(--ink)}
.qnav button.answered{background:var(--accent-soft);border-color:var(--accent);color:var(--accent-soft-ink)}
.qnav button.current{outline:2px solid var(--accent)}
.qnav button.flagged{border-color:var(--amber);box-shadow:inset 0 0 0 1px var(--amber)}

.ring-wrap{display:flex;align-items:center;gap:16px}
.ring{transform:rotate(-90deg)}
.ring .bgc{stroke:var(--surface2);fill:none}
.ring .fgc{stroke:var(--accent);fill:none;stroke-linecap:round;transition:stroke-dashoffset .4s ease}
.ring-val{font-family:"Archivo";font-weight:800;font-size:1.25rem}

.mod-tile{display:block;text-decoration:none;color:var(--ink)}
.mod-tile .card{height:100%;transition:border-color .15s}
.mod-tile:hover .card{border-color:var(--accent)}
.mod-num{font-family:"IBM Plex Mono",monospace;font-size:.72rem;color:var(--muted)}

.list-item{display:flex;align-items:center;gap:12px;padding:12px 14px;border:1px solid var(--line);border-radius:10px;background:var(--surface);margin-bottom:9px;text-decoration:none;color:var(--ink)}
.list-item:hover{border-color:var(--accent)}
.check{width:24px;height:24px;border-radius:99px;border:1.5px solid var(--line);flex-shrink:0;display:flex;align-items:center;justify-content:center;font-size:.75rem}
.check.done{background:var(--green);border-color:var(--green);color:#fff}
.crumb{font-size:.85rem;color:var(--muted);margin-bottom:14px}
.crumb a{color:var(--muted);text-decoration:none}
.crumb a:hover{color:var(--accent)}
textarea.io{width:100%;min-height:120px;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--ink);font-family:"IBM Plex Mono",monospace;font-size:.78rem;padding:10px}
.footer-note{margin-top:40px;font-size:.78rem;color:var(--muted);border-top:1px solid var(--line);padding-top:14px;max-width:70ch}
.hidden{display:none!important}

/* ---------- Login & Benutzerverwaltung (Server-Version) ---------- */
.qr-box{display:inline-block;background:#fff;padding:10px;border-radius:10px;border:1px solid var(--line);line-height:0}
.qr-box svg{display:block;max-width:100%;height:auto}
.code-input{font-family:"IBM Plex Mono",monospace;font-size:1.3rem!important;letter-spacing:.25em;text-align:center}
.rc-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 18px;font-family:"IBM Plex Mono",monospace;font-size:1rem;margin:10px 0}
.login-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:20px;background:var(--bg)}
.login-card{width:100%;max-width:400px;padding:30px 28px}
.login-card .brand{padding:0 0 18px}
.login-card label{display:block;font-size:.85rem;font-weight:600;margin:12px 0 4px}
.login-card input{width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:9px;background:var(--surface);color:var(--ink);font:inherit;box-sizing:border-box}
.login-card input:focus{outline:2px solid var(--focus);outline-offset:1px}
.login-err{margin-top:12px;padding:10px 12px;border-radius:9px;background:var(--red-soft);border:1px solid var(--red);font-size:.88rem;display:none}
.login-err.show{display:block}
.userbox{border-top:1px solid var(--line);padding:12px 10px 4px;margin-top:8px}
.userbox-name{font-weight:600;font-size:.92rem}
.userbox-sync{font-size:.7rem;color:var(--muted);margin:2px 0 8px;min-height:1em}
.userbox-actions{display:flex;gap:6px;flex-wrap:wrap}
.admin-table{width:100%;border-collapse:collapse;font-size:.88rem}
.admin-table th,.admin-table td{border-bottom:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:middle}
.admin-table th{font-family:"Archivo";font-size:.78rem}
.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:10px;align-items:end}
.form-grid label{font-size:.8rem;font-weight:600;display:block;margin-bottom:3px}
.form-grid input,.form-grid select{width:100%;padding:8px 10px;border:1px solid var(--line);border-radius:8px;background:var(--surface);color:var(--ink);font:inherit;box-sizing:border-box}

/* ---------- Endspurt: Pool-Umschalter, Freies Abrufen, Lücken- und Spickzettel ---------- */
.seg{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;background:var(--surface2);border:1px solid var(--line);border-radius:12px;padding:5px;margin:16px 0 6px;max-width:640px}
.seg button{border:1px solid transparent;background:none;border-radius:9px;padding:8px 10px;text-align:left;color:var(--ink);cursor:pointer;display:flex;flex-direction:column;gap:1px}
.seg button b{font-family:"Archivo";font-size:.92rem}
.seg button span{font-size:.74rem;color:var(--muted)}
.seg button.on{background:var(--surface);border-color:var(--accent);box-shadow:var(--shadow)}
.seg button:focus-visible{outline:2px solid var(--accent);outline-offset:1px}
.ab-hints{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:10px}
.ab-text{width:100%;min-height:340px;border:1px solid var(--line);border-radius:12px;background:var(--surface);color:var(--ink);font:inherit;font-size:1rem;line-height:1.6;padding:14px 16px;box-sizing:border-box;resize:vertical}
.ab-text:focus{outline:2px solid var(--accent);outline-offset:1px}
.ab-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.3fr);gap:20px;align-items:start}
.ab-notes{white-space:pre-wrap;background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:14px 16px;font-size:.93rem;position:sticky;top:12px;max-height:80vh;overflow:auto}
.ab-item{display:flex;gap:10px;align-items:flex-start;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:var(--surface);margin-bottom:8px;cursor:pointer;font-size:.92rem}
.ab-item input{margin-top:4px;width:18px;height:18px;flex-shrink:0;accent-color:var(--green)}
.ab-item:has(input:checked){border-color:var(--green);background:var(--green-soft)}
@media (max-width:760px){.ab-grid{grid-template-columns:1fr}.ab-notes{position:static;max-height:none}.seg{grid-template-columns:1fr}}
h2.cs-part{margin-top:34px;padding-bottom:6px;border-bottom:2px solid var(--accent)}
.cheat .cs-sec{margin-bottom:22px}
@media print{
  .sidebar,.topbar,.overlay,.no-print,.footer-note{display:none!important}
  .app{display:block}.main{padding:0;max-width:none}
  body{background:#fff;color:#000;font-size:11pt}
  .req,.cs-sec{break-inside:avoid}.card,.req{box-shadow:none}
  h2{break-after:avoid}
}

/* ---------- Darstellung: Auto / Hell / Dunkel ---------- */
:root{color-scheme:light dark}
:root[data-theme="light"]{color-scheme:light}
:root[data-theme="dark"]{color-scheme:dark}
.theme-sw{display:grid;grid-template-columns:repeat(3,1fr);gap:3px;background:var(--surface2);border:1px solid var(--line);border-radius:9px;padding:3px;margin:4px 10px 6px}
.theme-sw button{border:1px solid transparent;background:none;border-radius:7px;padding:5px 2px;font-size:.76rem;color:var(--muted);cursor:pointer;white-space:nowrap}
.theme-sw button:hover{color:var(--ink)}
.theme-sw button.on{background:var(--surface);border-color:var(--line);color:var(--ink);font-weight:600;box-shadow:var(--shadow)}
.theme-sw button:focus-visible{outline:2px solid var(--accent);outline-offset:1px}