:root{
  --bg:#0f1117; --bg2:#161a23; --bg3:#1e2430; --border:#2a3142;
  --text:#e8ecf4; --muted:#8b94a7; --accent:#6c8cff; --accent2:#8f6cff;
  --green:#3ecf8e; --red:#ff6b6b; --yellow:#ffd166; --orange:#ff9f43;
  --radius:14px;
}
/* ---------- Светлая тема ---------- */
body.light{
  --bg:#f4f6fb; --bg2:#ffffff; --bg3:#eef1f7; --border:#d8deea;
  --text:#1c2333; --muted:#5c6577; --accent:#4a6cf7; --accent2:#7b4af7;
  --green:#118a63; --red:#c93b3b; --yellow:#a87900; --orange:#d97a1f;
}
body.light pre{background:#f0f2f8}
body.light code{color:#2456c4}
body.light .flash-front{background:linear-gradient(135deg,#e8edff,#f0e8ff)}
body.light .streak-banner{background:linear-gradient(135deg,#fff7e6,#f3edff);border-color:#e6d9ae}
body.light .ai-tip{background:linear-gradient(135deg,#eef1ff,#f6efff);border-color:#c9d2f5}
body.light .cert{background:linear-gradient(135deg,#f6f8ff,#faf6ff)}
body.light .quiz-opt.correct{background:#e4f7ee}
body.light .quiz-opt.wrong{background:#fdecec}
body.light .task-input,body.light .prompt-text{background:#f7f8fc}
body.light .week-dots .dot.on{color:#fff}
body.light .logo span{color:#3a5bf0}

*{box-sizing:border-box;margin:0;padding:0}
body{background:var(--bg);color:var(--text);font-family:'Segoe UI',system-ui,sans-serif;line-height:1.55;transition:background .25s,color .25s}
button{font-family:inherit}
.icon-btn{background:var(--bg3);border:1px solid var(--border);border-radius:999px;padding:5px 10px;font-size:15px;cursor:pointer;line-height:1}
.icon-btn:hover{border-color:var(--accent)}

/* ---------- Top bar ---------- */
.topbar{display:flex;align-items:center;gap:14px;padding:10px 18px;background:var(--bg2);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:20}
.menu-btn{display:none;background:none;border:1px solid var(--border);color:var(--text);border-radius:8px;padding:4px 10px;font-size:18px;cursor:pointer}
.logo{font-weight:800;font-size:19px;cursor:pointer;letter-spacing:.3px}
.logo span{color:var(--accent)}
.stats{margin-left:auto;display:flex;gap:10px;min-width:0}
#userStat{min-width:0;max-width:210px;overflow:hidden}
.uname{display:inline-block;max-width:130px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;vertical-align:bottom}
.stat{background:var(--bg3);border:1px solid var(--border);padding:5px 12px;border-radius:999px;font-size:14px;white-space:nowrap}
.stat b{color:var(--yellow)}
.stat.level b{color:var(--accent)}
.streak-fire{animation:pulse 1.2s infinite}
@keyframes pulse{50%{transform:scale(1.15)}}

/* ---------- Layout ---------- */
.layout{display:flex;min-height:calc(100vh - 54px)}
.sidebar{width:290px;flex-shrink:0;background:var(--bg2);border-right:1px solid var(--border);padding:14px 10px;overflow-y:auto;height:calc(100vh - 54px);position:sticky;top:54px}
.nav-section{font-size:11px;text-transform:uppercase;letter-spacing:1.5px;color:var(--muted);margin:16px 8px 6px}
.nav-item{padding:9px 12px;border-radius:10px;cursor:pointer;font-size:14px;margin-bottom:2px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.nav-item:hover{background:var(--bg3)}
.nav-item.active{background:var(--bg3);outline:1px solid var(--accent);color:#fff}
.nav-item .prog{margin-left:auto;font-size:11px;color:var(--muted)}
.nav-item .done-mark{margin-left:auto;color:var(--green)}
.nav-hint{width:100%;font-size:11px;color:var(--muted);padding-left:24px}
.main{flex:1;padding:28px clamp(16px,4vw,48px);max-width:980px}

/* ---------- Cards & general ---------- */
.card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:22px;margin-bottom:16px}
h1{font-size:26px;margin-bottom:6px}
h2{font-size:20px;margin:18px 0 8px}
.sub{color:var(--muted);margin-bottom:18px}
.pill{display:inline-block;background:var(--bg3);border:1px solid var(--border);border-radius:999px;padding:3px 12px;font-size:12px;color:var(--muted);margin-right:6px}
.btn{background:linear-gradient(135deg,var(--accent),var(--accent2));border:none;color:#fff;padding:11px 22px;border-radius:10px;font-size:15px;font-weight:600;cursor:pointer;transition:.15s}
.btn:hover{filter:brightness(1.12)}
.btn.ghost{background:var(--bg3);border:1px solid var(--border)}
.btn.small{padding:7px 14px;font-size:13px}
.btn:disabled{opacity:.45;cursor:default}
.progressbar{height:9px;background:var(--bg3);border-radius:99px;overflow:hidden;margin:8px 0}
.progressbar i{display:block;height:100%;background:linear-gradient(90deg,var(--accent),var(--accent2));border-radius:99px;transition:width .4s}

/* ---------- Dashboard ---------- */
.dash-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:14px;margin-bottom:20px}
.dash-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:18px;text-align:center}
.dash-card .big{font-size:32px;font-weight:800;margin:4px 0}
.dash-card .lbl{color:var(--muted);font-size:13px}
.module-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(270px,1fr));gap:14px}
.level-head{font-size:15px;font-weight:700;color:var(--accent);margin:20px 0 10px;padding-bottom:6px;border-bottom:1px solid var(--border)}
.mod-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:18px;cursor:pointer;transition:.15s;position:relative}
.mod-card:hover{border-color:var(--accent);transform:translateY(-2px)}
.mod-card .icon{font-size:28px}
.mod-card h3{font-size:15px;margin:8px 0 2px}
.mod-card .en{font-size:12px;color:var(--muted);font-style:italic}
.mod-card .badge-done{position:absolute;top:12px;right:12px;color:var(--green);font-size:18px}
.streak-banner{display:flex;align-items:center;gap:16px;background:linear-gradient(135deg,#2b1e0e,#1e1a2e);border:1px solid #4a3d1e;border-radius:var(--radius);padding:16px 22px;margin-bottom:20px}
.streak-banner .fire{font-size:38px}
.week-dots{display:flex;gap:6px;margin-top:6px}
.week-dots .dot{width:22px;height:22px;border-radius:50%;background:var(--bg3);border:1px solid var(--border);font-size:11px;display:flex;align-items:center;justify-content:center;color:var(--muted)}
.week-dots .dot.on{background:var(--orange);color:#000;border-color:var(--orange);font-weight:700}

/* ---------- Module view / tabs ---------- */
.tabs{display:flex;gap:8px;margin-bottom:18px;flex-wrap:wrap}
.tab{padding:9px 18px;border-radius:10px;background:var(--bg3);border:1px solid var(--border);cursor:pointer;font-size:14px;color:var(--muted)}
.tab.active{color:#fff;border-color:var(--accent);background:var(--bg2)}
.lesson-sec{margin-bottom:14px}
.lesson-sec h2{color:var(--accent);font-size:18px}
.lesson-sec ul{padding-left:22px;margin:6px 0}
.lesson-sec li{margin-bottom:4px}
.lesson-sec b{color:#fff}
.example{background:var(--bg3);border-left:3px solid var(--green);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.example::before{content:"💡 Пример: ";font-weight:700;color:var(--green)}
.warn{background:var(--bg3);border-left:3px solid var(--red);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.warn::before{content:"⚠️ ";font-weight:700}
.ai-tip{background:linear-gradient(135deg,#171d33,#1d1730);border:1px solid #35407a;border-radius:10px;padding:12px 16px;margin:10px 0;font-size:14px}
.ai-tip::before{content:"🤖 Где помогает ИИ: ";font-weight:700;color:var(--accent)}
pre{background:#0c0e14;border:1px solid var(--border);border-radius:8px;padding:12px;overflow-x:auto;font-size:13px;margin:8px 0}
code{font-family:Consolas,monospace;color:#9ecbff;font-size:.93em}
table.t{border-collapse:collapse;width:100%;margin:8px 0;font-size:14px}
table.t th,table.t td{border:1px solid var(--border);padding:7px 10px;text-align:left}
table.t th{background:var(--bg3)}

/* ---------- Flashcards ---------- */
.flash-wrap{perspective:1200px;max-width:560px;margin:0 auto}
.flashcard{position:relative;height:290px;transform-style:preserve-3d;transition:transform .5s;cursor:pointer}
.flashcard.flipped{transform:rotateY(180deg)}
.flash-face{position:absolute;inset:0;backface-visibility:hidden;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:28px;border-radius:var(--radius);border:1px solid var(--border)}
.flash-front{background:linear-gradient(135deg,#1a2036,#201a36);font-size:20px;font-weight:700}
.flash-back{background:var(--bg2);transform:rotateY(180deg);font-size:16px}
.flash-controls{display:flex;gap:10px;justify-content:center;margin-top:18px;flex-wrap:wrap}
.flash-count{text-align:center;color:var(--muted);margin-top:10px;font-size:13px}
.flash-hint{text-align:center;color:var(--muted);font-size:12px;margin-top:6px}

/* ---------- Quiz ---------- */
.quiz-q{font-size:18px;font-weight:700;margin-bottom:16px}
.quiz-opts{display:flex;flex-direction:column;gap:10px}
.quiz-opt{background:var(--bg3);border:1px solid var(--border);border-radius:10px;padding:13px 16px;cursor:pointer;text-align:left;font-size:15px;color:var(--text);transition:.12s}
.quiz-opt:hover{border-color:var(--accent)}
.quiz-opt.correct{border-color:var(--green);background:#12291f}
.quiz-opt.wrong{border-color:var(--red);background:#2b1517}
.quiz-opt:disabled{cursor:default}
.explain{margin-top:14px;padding:12px 16px;border-radius:10px;background:var(--bg3);border-left:3px solid var(--accent);font-size:14px}
.quiz-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;color:var(--muted);font-size:14px}
.timer{font-weight:800;font-size:18px;color:var(--yellow)}
.timer.low{color:var(--red);animation:pulse .6s infinite}
.result-emoji{font-size:52px;text-align:center}
.result-score{font-size:34px;font-weight:800;text-align:center;margin:8px 0}
.result-msg{text-align:center;color:var(--muted);margin-bottom:18px}
.xp-pop{position:fixed;top:64px;right:24px;background:var(--bg3);border:1px solid var(--yellow);color:var(--yellow);padding:8px 16px;border-radius:99px;font-weight:700;z-index:50;animation:xpfly 1.6s forwards}
@keyframes xpfly{0%{opacity:0;transform:translateY(10px)}15%{opacity:1;transform:translateY(0)}80%{opacity:1}100%{opacity:0;transform:translateY(-18px)}}

/* ---------- Badges ---------- */
.badge-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:14px}
.badge-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:18px;text-align:center}
.badge-card.locked{opacity:.35;filter:grayscale(1)}
.badge-card .icon{font-size:36px}
.badge-card h4{margin:6px 0 4px;font-size:14px}
.badge-card p{font-size:12px;color:var(--muted)}

/* ---------- Практика ---------- */
.task-input{width:100%;background:#0c0e14;border:1px solid var(--border);border-radius:10px;color:var(--text);padding:12px 14px;font-size:14px;font-family:inherit;resize:vertical}
.task-input:focus{outline:none;border-color:var(--accent)}
.crit-list{list-style:none;padding-left:0;margin:8px 0}
.crit-list li{margin-bottom:4px;font-size:14px}

/* ---------- Промпт-библиотека ---------- */
.prompt-item{padding:16px 20px;margin-bottom:10px}
.prompt-text{margin-top:8px;background:#0c0e14;border:1px solid var(--border);border-radius:8px;padding:10px 14px;font-size:13px;color:var(--muted);font-family:Consolas,monospace;white-space:pre-wrap}

/* ---------- Сертификат ---------- */
.cert{background:linear-gradient(135deg,#1a2036,#241a36);border:2px solid var(--accent);border-radius:18px;padding:10px;max-width:700px}
.cert-inner{border:1px dashed var(--border);border-radius:12px;padding:36px 28px;text-align:center}
.cert-title{font-size:30px;font-weight:800;letter-spacing:6px;margin:8px 0;background:linear-gradient(90deg,var(--accent),var(--accent2));-webkit-background-clip:text;background-clip:text;color:transparent}
.cert-sub{color:var(--muted);font-size:14px;margin:6px 0}
.cert-name{font-size:26px;font-weight:800;margin:8px 0;border-bottom:1px solid var(--border);display:inline-block;padding:0 24px 4px}
.cert-course{font-size:17px;font-weight:700;margin:10px 0}
.cert-details{font-size:13px;color:var(--muted);margin-top:10px}
@media print{
  body{background:#fff;color:#000}
  .topbar,.sidebar,.no-print,h1{display:none!important}
  .main{padding:0;max-width:100%}
  .cert{border-color:#444;background:#fff;margin:40px auto}
  .cert-title{color:#1a2036;-webkit-text-fill-color:#1a2036}
  .cert-sub,.cert-details{color:#555}
  .cert-name,.cert-course{color:#000}
}

/* ---------- Учебные блоки (методика для новичков) ---------- */
.newwords{display:flex;flex-wrap:wrap;gap:8px;margin:10px 0}
.newwords span{background:var(--bg3);border:1px solid var(--accent);border-radius:999px;padding:4px 13px;font-size:13px}
.ministory{background:var(--bg3);border-left:3px solid var(--yellow);border-radius:8px;padding:12px 16px;margin:10px 0;font-size:14.5px}
.ministory::before{content:"📖 История: ";font-weight:700;color:var(--yellow)}
.analogy{background:var(--bg3);border-left:3px solid var(--accent2);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.analogy::before{content:"🧩 Аналогия: ";font-weight:700;color:var(--accent2)}
.why{background:var(--bg3);border-left:3px solid var(--orange);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.why::before{content:"🎯 Зачем тебе это: ";font-weight:700;color:var(--orange)}
.memo{background:var(--bg3);border-left:3px solid var(--green);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.memo::before{content:"🧠 Запомни: ";font-weight:700;color:var(--green)}
.fact{background:var(--bg3);border-left:3px solid var(--yellow);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.fact::before{content:"💡 Интересный факт: ";font-weight:700;color:var(--yellow)}
.tldr{background:var(--bg3);border:1px dashed var(--accent);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14.5px}
.tldr::before{content:"⚡ Если совсем коротко: ";font-weight:700;color:var(--accent)}
.nextup{color:var(--muted);font-size:14px;margin-top:10px}
.nextup::before{content:"➡️ Что дальше: ";font-weight:700;color:var(--text)}
.mist{margin:8px 0;font-size:14px}
.mist .m-think{color:var(--red)}
.mist .m-real{color:var(--green)}
.selfcheck details{background:var(--bg3);border:1px solid var(--border);border-radius:8px;padding:10px 14px;margin-bottom:8px}
.selfcheck summary{font-weight:600;cursor:pointer}
.selfcheck details p{margin-top:8px;color:var(--muted);font-size:14px}
.homework{background:var(--bg3);border-left:3px solid var(--accent);border-radius:8px;padding:10px 14px;margin:8px 0;font-size:14px}
.homework::before{content:"🏠 Практика без компьютера: ";font-weight:700;color:var(--accent)}

/* ---------- Аккаунты / доступ ---------- */
.auth-backdrop{position:fixed;inset:0;background:rgba(8,10,16,.88);backdrop-filter:blur(6px);z-index:100;display:flex;align-items:center;justify-content:center;padding:16px}
body.light .auth-backdrop{background:rgba(240,243,250,.92)}
.auth-box{background:var(--bg2);border:1px solid var(--border);border-radius:18px;padding:28px;width:100%;max-width:400px;box-shadow:0 20px 60px rgba(0,0,0,.4)}
.auth-err{color:var(--red);font-size:13px;min-height:18px;margin-bottom:8px}
.auth-divider{text-align:center;color:var(--muted);font-size:12px;margin:12px 0}
.locked-card{opacity:.65}
.locked-card:hover{opacity:1}

/* ---------- Responsive ---------- */
@media (max-width:860px){
  .menu-btn{display:block}
  .sidebar{position:fixed;left:-300px;top:54px;z-index:30;transition:left .25s;box-shadow:8px 0 30px rgba(0,0,0,.5);width:min(290px,85vw)}
  .sidebar.open{left:0}
  .stats{gap:6px}.stat{font-size:12px;padding:4px 8px}
}
@media (max-width:640px){
  .topbar{padding:8px 10px;gap:8px}
  .logo{font-size:15px;white-space:nowrap}
  .stats{gap:4px;flex-wrap:nowrap;overflow:hidden}
  .stat{font-size:11px;padding:3px 7px;white-space:nowrap}
  #levelStat{display:none}                        /* уровень виден в профиле */
  #userStat b{max-width:72px;overflow:hidden;text-overflow:ellipsis;display:inline-block;vertical-align:bottom}
  .icon-btn{padding:4px 7px;font-size:13px}
  .main{padding:16px 12px}
  h1{font-size:21px}
  h2{font-size:17px}
  .card{padding:16px 14px}
  .quiz-q{font-size:16px}
  .quiz-opt{padding:12px 12px;font-size:14px}
  .streak-banner{flex-wrap:wrap;padding:14px 16px;gap:10px}
  .streak-banner .fire{font-size:30px}
  .dash-grid{grid-template-columns:repeat(2,1fr);gap:10px}
  .dash-card{padding:12px}
  .dash-card .big{font-size:24px}
  .module-grid{grid-template-columns:1fr}
  .lesson-sec{overflow-x:auto}                    /* таблицы в уроках скроллятся, а не ломают вёрстку */
  table.t{font-size:12.5px}
  table.t th,table.t td{padding:5px 7px}
  pre{font-size:11.5px;padding:10px}
  .flashcard{height:320px}
  .flash-face{padding:18px;font-size:15px}
  .flash-front{font-size:17px}
  .btn{padding:10px 16px;font-size:14px}
  .tabs{gap:6px}
  .tab{padding:8px 12px;font-size:13px}
  .cert-inner{padding:24px 12px}
  .cert-title{font-size:22px;letter-spacing:3px}
  .cert-name{font-size:20px;padding:0 10px 4px}
  .auth-box{padding:20px 16px}
  .week-dots .dot{width:19px;height:19px;font-size:10px}
  .badge-grid{grid-template-columns:repeat(2,1fr);gap:10px}
  .xp-pop{top:52px;right:10px;font-size:13px}
}