:root{
  --ink:#1b1d24;
  --ink-soft:#41454f;
  --paper:#f4f0e7;
  --paper-2:#ece6d8;
  --card:#fffdf8;
  --line:#ddd5c4;
  --accent:#c4711b;
  --accent-deep:#9c560f;
  --accent-soft:#f7e6cf;
  --ok:#2f7a5b;
  --ok-soft:#e0f0e7;
  --bad:#bb3a2c;
  --bad-soft:#f6e0dd;
  --warn:#9a6700;
  --warn-soft:#f5ecd0;
  --shadow:0 1px 2px rgba(27,29,36,.06),0 8px 30px rgba(27,29,36,.08);
  --shadow-sm:0 1px 3px rgba(27,29,36,.08),0 4px 14px rgba(27,29,36,.06);
  --shadow-btn:0 2px 8px rgba(196,113,27,.28);
  --radius:18px;
  --focus:0 0 0 3px rgba(196,113,27,.22);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Golos Text',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;
  background:var(--paper);
  color:var(--ink);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  background-image:radial-gradient(circle at 1px 1px, rgba(27,29,36,.04) 1px, transparent 0);
  background-size:22px 22px;
}
h1,h2,h3,.display{font-family:'Unbounded',sans-serif;line-height:1.15;letter-spacing:-.01em}
a{color:var(--accent-deep);text-decoration:none;transition:color .15s}
a:hover{color:var(--accent)}

.app{max-width:1180px;margin:0 auto;padding:0 16px}
.hidden{display:none!important}

/* ====== top bar ====== */
header.bar{
  position:sticky;top:0;z-index:40;
  background:rgba(244,240,231,.92);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
  box-shadow:0 1px 0 rgba(255,255,255,.5) inset;
}
.bar-inner{max-width:1180px;margin:0 auto;padding:12px 16px;display:flex;align-items:center;gap:12px}
.brand{display:flex;align-items:center;gap:10px;font-family:'Unbounded',sans-serif;font-weight:700;font-size:15px;letter-spacing:-.02em}
.brand .logo{width:32px;height:32px;flex:none;filter:drop-shadow(0 2px 4px rgba(196,113,27,.15))}
.bar-spacer{flex:1}
.bar-user{
  font-size:13px;color:var(--ink-soft);display:flex;align-items:center;gap:8px;
  background:var(--card);border:1px solid var(--line);border-radius:999px;padding:6px 14px 6px 10px;
  box-shadow:var(--shadow-sm);white-space:nowrap;
}
.bar-user b{color:var(--ink);font-weight:600}
.gloss-btn,.menu-toggle{
  display:inline-flex;align-items:center;gap:7px;background:var(--card);
  border:1.5px solid var(--line);border-radius:12px;padding:8px 13px;cursor:pointer;
  font-family:'Golos Text',sans-serif;font-size:13px;font-weight:600;color:var(--ink);
  transition:background .15s,border-color .15s,transform .12s,box-shadow .15s;
  box-shadow:var(--shadow-sm);
}
.gloss-btn:hover,.menu-toggle:hover{background:var(--paper-2);border-color:#cfc5b0;transform:translateY(-1px)}
.gloss-btn svg,.menu-toggle svg{width:17px;height:17px;display:block;flex:none}

.modal-overlay{position:fixed;inset:0;z-index:60;background:rgba(27,29,36,.52);backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;padding:20px;animation:fade .2s ease}
@keyframes fade{from{opacity:0}to{opacity:1}}
.modal{background:var(--card);border:1px solid var(--line);border-radius:22px;max-width:560px;width:100%;max-height:82vh;display:flex;flex-direction:column;box-shadow:var(--shadow);overflow:hidden}
.modal-head{display:flex;align-items:center;justify-content:space-between;padding:20px 24px;border-bottom:1px solid var(--line);background:linear-gradient(180deg,#fffdf8,var(--paper-2))}
.modal-head h3{font-size:18px}
.modal-close{background:var(--paper-2);border:none;width:36px;height:36px;border-radius:50%;cursor:pointer;font-size:15px;color:var(--ink-soft);transition:.15s}
.modal-close:hover{background:var(--line);color:var(--ink)}
.modal-body{padding:8px 24px 24px;overflow:auto}
.gloss-term{padding:16px 0;border-bottom:1px dashed var(--line)}
.gloss-term:last-child{border-bottom:none}
.gloss-term dt{font-family:'Unbounded',sans-serif;font-size:14px;font-weight:600;color:var(--accent-deep);margin-bottom:5px}
.gloss-term dd{margin:0;color:#2a2d35;font-size:14px;line-height:1.55}
.progress-wrap{height:6px;background:var(--paper-2);width:100%}
.progress-bar{height:100%;width:0;background:linear-gradient(90deg,var(--accent),#e8943a,var(--accent-deep));transition:width .45s cubic-bezier(.4,0,.2,1);box-shadow:0 0 12px rgba(196,113,27,.35)}

/* ====== buttons ====== */
.btn{
  font-family:'Golos Text',sans-serif;font-weight:600;font-size:15px;line-height:1.2;
  border:none;border-radius:999px;padding:13px 26px;cursor:pointer;
  background:var(--ink);color:#fff;
  transition:transform .12s ease,box-shadow .15s ease,background .2s ease,opacity .2s;
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  text-decoration:none;white-space:nowrap;
}
.btn:hover{transform:translateY(-1px);color:#fff}
.btn:active{transform:translateY(0)}
.btn:focus-visible{outline:none;box-shadow:var(--focus)}
.btn:disabled{opacity:.45;cursor:not-allowed;transform:none;box-shadow:none}
.btn.accent{background:linear-gradient(180deg,#d47a22,var(--accent));box-shadow:var(--shadow-btn)}
.btn.accent:hover{background:linear-gradient(180deg,var(--accent),var(--accent-deep));box-shadow:0 4px 14px rgba(196,113,27,.35)}
.btn.ghost{background:var(--card);color:var(--ink);border:1.5px solid var(--line);box-shadow:var(--shadow-sm)}
.btn.ghost:hover{background:var(--paper-2);border-color:#cfc5b0;color:var(--ink)}
.btn.sm{padding:9px 18px;font-size:14px}
.btn-block{width:100%}

/* ====== start screen ====== */
.start{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:48px 16px}
.start-card{
  background:var(--card);border:1px solid var(--line);border-radius:28px;
  max-width:520px;width:100%;padding:48px 42px;box-shadow:var(--shadow);position:relative;overflow:hidden;
}
.start-card.wide{max-width:640px}
.start-card::before{content:"";position:absolute;top:-70px;right:-70px;width:200px;height:200px;border-radius:50%;background:radial-gradient(circle,var(--accent-soft),transparent 70%);opacity:.85}
.start-card::after{content:"";position:absolute;bottom:-40px;left:-40px;width:120px;height:120px;border-radius:50%;background:var(--ok-soft);opacity:.35}
.start-shield{width:68px;height:68px;position:relative;z-index:1;filter:drop-shadow(0 4px 12px rgba(196,113,27,.2))}
.start h1{font-size:clamp(24px,5vw,32px);margin:22px 0 12px;position:relative;z-index:1}
.start h2{font-size:clamp(20px,4vw,26px);margin-bottom:12px;position:relative;z-index:1}
.start p.lead{color:var(--ink-soft);margin-bottom:28px;position:relative;z-index:1;font-size:16px}
.field{margin-bottom:18px;position:relative;z-index:1}
.field label{display:block;font-size:13px;font-weight:600;margin-bottom:8px;color:var(--ink-soft);letter-spacing:.01em}
.field input,.field select,.field textarea{
  width:100%;padding:14px 16px;border:1.5px solid var(--line);border-radius:14px;
  font-family:'Golos Text',sans-serif;font-size:16px;background:var(--paper);
  transition:border-color .2s,box-shadow .2s,background .2s;
}
.field input:hover,.field select:hover,.field textarea:hover{background:#f9f6ef}
.field input:focus,.field select:focus,.field textarea:focus{outline:none;border-color:var(--accent);box-shadow:var(--focus);background:var(--card)}
.start .note{font-size:12px;color:var(--ink-soft);margin-top:16px;background:var(--paper-2);padding:12px 14px;border-radius:12px;line-height:1.5;position:relative;z-index:1;border:1px solid var(--line)}

/* dashboard stats */
.dash-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:14px;margin:24px 0;position:relative;z-index:1}
.dash-stat{background:var(--paper);border:1px solid var(--line);border-radius:16px;padding:16px 18px;text-align:center}
.dash-stat b{display:block;font-family:'Unbounded',sans-serif;font-size:28px;font-weight:700;color:var(--ink);line-height:1.1;margin-bottom:4px}
.dash-stat span{font-size:12px;color:var(--ink-soft);font-weight:600;text-transform:uppercase;letter-spacing:.04em}
.dash-progress{position:relative;z-index:1;margin:8px 0 4px;height:10px;background:var(--paper-2);border-radius:999px;overflow:hidden;border:1px solid var(--line)}
.dash-progress-fill{height:100%;background:linear-gradient(90deg,var(--accent),var(--accent-deep));border-radius:999px;transition:width .5s ease}
.dash-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:28px;position:relative;z-index:1}

/* ====== main layout ====== */
.layout{display:grid;grid-template-columns:272px 1fr;gap:32px;padding:32px 0 80px}
nav.toc{
  position:sticky;top:88px;align-self:start;
  padding:8px;background:var(--card);border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow-sm);
}
nav.toc ol{list-style:none;padding:4px}
nav.toc li{margin:3px 0}
nav.toc button{
  width:100%;text-align:left;border:none;background:transparent;cursor:pointer;
  font-family:'Golos Text',sans-serif;font-size:14px;color:var(--ink-soft);
  padding:11px 13px;border-radius:12px;display:flex;align-items:center;gap:10px;
  transition:background .15s,color .15s,transform .12s,box-shadow .15s;
}
nav.toc button:hover{background:var(--paper-2);color:var(--ink)}
nav.toc button.active{
  background:var(--ink);color:#fff;font-weight:600;
  box-shadow:0 4px 14px rgba(27,29,36,.18);transform:translateX(2px);
}
nav.toc button.active .dot{background:var(--accent);box-shadow:0 0 0 2px rgba(255,255,255,.25)}
nav.toc button.done .dot{background:var(--ok)}
nav.toc button.locked{opacity:.38;cursor:not-allowed;pointer-events:none}
.dot{width:9px;height:9px;border-radius:50%;background:var(--line);flex:none;transition:background .2s}
.toc-label{font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:var(--ink-soft);font-weight:700;padding:14px 13px 8px;margin-top:4px;border-top:1px dashed var(--line)}
.toc-label:first-child{border-top:none;margin-top:0;padding-top:8px}
.toc-num{font-size:11px;opacity:.55;font-variant-numeric:tabular-nums;margin-left:auto}

main.content{min-width:0}

.section{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:40px;box-shadow:var(--shadow);animation:rise .4s ease;
}
@keyframes rise{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:none}}
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;font-size:11px;font-weight:700;
  text-transform:uppercase;letter-spacing:.1em;color:var(--accent-deep);
  background:linear-gradient(135deg,var(--accent-soft),#fff8ef);padding:7px 14px;
  border-radius:999px;margin-bottom:18px;border:1px solid rgba(196,113,27,.15);
}
.section h2{font-size:clamp(22px,4vw,30px);margin-bottom:10px}
.section .sub{color:var(--ink-soft);font-size:15px;margin-bottom:24px;line-height:1.55}
.section h3{font-size:18px;margin:28px 0 10px;display:flex;align-items:center;gap:10px}
.section h3 .h3bar{width:4px;height:20px;background:linear-gradient(180deg,var(--accent),var(--accent-deep));border-radius:3px;flex:none}
.section p{margin:12px 0;color:#2a2d35}
.section ul{margin:12px 0 12px 4px;padding-left:20px}
.section li{margin:7px 0}
.section img,.section figure img{max-width:100%;height:auto;border-radius:14px;border:1px solid var(--line);display:block;margin:12px 0}
.section figure{margin:20px 0;text-align:center}
.section figure figcaption{font-size:13px;color:var(--ink-soft);margin-top:8px}
.callout{background:var(--accent-soft);border-left:4px solid var(--accent);border-radius:0 14px 14px 0;padding:16px 20px;margin:22px 0;font-size:15px;line-height:1.55}
.callout b{color:var(--accent-deep)}
.callout.danger{background:var(--bad-soft);border-left-color:var(--bad)}
.callout.danger b{color:var(--bad)}
.checklist{list-style:none;padding:0;margin:16px 0}
.checklist li{display:flex;gap:11px;align-items:flex-start;padding:10px 0;border-bottom:1px dashed var(--line)}
.checklist li:last-child{border-bottom:none}
.check-ic{width:20px;height:20px;flex:none;color:var(--ok);margin-top:2px}
.example{background:var(--paper);border:1px solid var(--line);border-radius:14px;padding:18px 20px;margin:16px 0}
.example .ex-tag{font-family:'Unbounded',sans-serif;font-size:13px;color:var(--accent-deep);margin-bottom:6px}
.hero-ic{width:80px;height:80px;margin-bottom:6px}

.quiz{margin-top:34px;border-top:2px solid var(--line);padding-top:30px}
.quiz-head{display:flex;align-items:center;gap:10px;margin-bottom:6px}
.quiz-head h3{margin:0;font-size:19px}
.quiz-sub{color:var(--ink-soft);font-size:14px;margin-bottom:20px}
.q{background:var(--paper);border:1px solid var(--line);border-radius:14px;padding:20px 22px;margin-bottom:16px;box-shadow:var(--shadow-sm)}
.q-text{font-weight:600;margin-bottom:14px;display:flex;gap:10px;line-height:1.45}
.q-text .qn{color:var(--accent-deep);font-family:'Unbounded',sans-serif;font-size:14px;flex:none}
.opt{
  display:flex;align-items:center;gap:12px;padding:13px 15px;border:1.5px solid var(--line);
  border-radius:12px;margin:8px 0;cursor:pointer;transition:.15s;background:var(--card);
}
.opt:hover{border-color:var(--accent);background:#fffefb;transform:translateX(2px)}
.opt input{accent-color:var(--accent);width:18px;height:18px;flex:none}
.opt.correct{border-color:var(--ok);background:var(--ok-soft)}
.opt.wrong{border-color:var(--bad);background:var(--bad-soft)}
.opt.locked{cursor:default;pointer-events:none;transform:none}
.opt .mark{margin-left:auto;font-weight:700;font-size:13px}
.opt.correct .mark{color:var(--ok)}
.opt.wrong .mark{color:var(--bad)}
.quiz-actions{display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin-top:8px}
.quiz-result{font-weight:600;font-size:15px;padding:10px 14px;border-radius:12px}
.quiz-result.pass{color:var(--ok);background:var(--ok-soft)}
.quiz-result.fail{color:var(--bad);background:var(--bad-soft)}

.pager{display:flex;justify-content:space-between;gap:12px;margin-top:28px;padding-top:8px}

.result-card{text-align:center;padding:20px 0}
.result-badge{width:110px;height:110px;margin:0 auto 18px}
.score-big{font-family:'Unbounded',sans-serif;font-size:54px;font-weight:900;line-height:1}
.score-label{font-size:15px;color:var(--ink-soft);margin-top:4px}
.verdict{display:inline-block;font-family:'Unbounded',sans-serif;font-weight:700;font-size:20px;padding:10px 26px;border-radius:999px;margin:18px 0}
.verdict.pass{background:var(--ok-soft);color:var(--ok)}
.verdict.fail{background:var(--bad-soft);color:var(--bad)}
.result-code{background:var(--ink);color:#f4f0e7;font-family:ui-monospace,Menlo,monospace;font-size:13px;word-break:break-all;padding:16px;border-radius:12px;margin:18px 0;text-align:left;line-height:1.7}
.result-meta{display:flex;justify-content:center;gap:30px;flex-wrap:wrap;margin:16px 0;color:var(--ink-soft);font-size:14px}
.result-meta b{display:block;color:var(--ink);font-size:18px;font-family:'Unbounded',sans-serif}

.menu-toggle .mt-label{display:inline}
.layout.nav-closed{grid-template-columns:1fr}
.layout.nav-closed nav.toc{display:none}
.bar-actions{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.bar-actions form{margin:0}
@media(max-width:860px){
  .layout{grid-template-columns:1fr!important;gap:0;padding-top:16px}
  nav.toc{position:fixed;inset:60px 0 auto 0;top:60px;background:var(--card);border-bottom:1px solid var(--line);padding:14px 16px;z-index:30;box-shadow:var(--shadow);max-width:100%;border-radius:0 0 16px 16px;overflow:visible}
  .menu-toggle .mt-label{display:none}
  .gloss-label{display:none}
  .bar-user{display:none}
  .section{padding:26px 20px;border-radius:16px}
  .start-card{padding:36px 24px}
  .bar-actions .btn-long{display:none}
}
@media(max-width:480px){
  .pager{flex-direction:column}
  .pager .btn{width:100%;justify-content:center}
  .result-meta{gap:18px}
  .dash-actions .btn{flex:1;min-width:calc(50% - 6px)}
}
.limits-bar{background:linear-gradient(180deg,var(--paper-2),var(--paper));border-bottom:1px solid var(--line);padding:10px 16px;font-size:13px;color:var(--ink-soft);display:flex;flex-wrap:wrap;gap:18px;justify-content:center}
.limits-bar b{color:var(--ink);font-weight:600}
.limits-bar.hidden{display:none!important}

.form-grid{display:grid;gap:16px}
.form-grid .field{margin-bottom:0}