/* Wspólny wygląd kursów (C#, React): nagłówek, spis treści, karty lekcji, kod, ocena zrozumienia.
   Style komponentów treści konkretnego kursu: course-csharp.css, course-react.css. */

body.course{
  /* aliasy – treść lekcji korzysta z tych nazw */
  --text:var(--ink); --text-muted:var(--muted); --text-faint:#94a3b8;
  --border:var(--line); --border-strong:#c7d2de;
  --surface:#fff; --surface-alt:#eef2f6;
  --accent:var(--navy); --accent-strong:var(--navy2); --accent-soft:#e7ecf2; --accent-contrast:#fff;
  --good:#047857; --good-bg:#ecfdf5; --bad:#be123c; --bad-bg:#fff1f2;
  --shadow:0 1px 3px rgba(15,23,42,.06);
  --font-mono:ui-monospace,SFMono-Regular,Consolas,monospace;
  --code-bg:#2b376b; --code-head:#33408c; --code-text:#e2e8f0; --code-comment:#a9b4d9;
  --code-string:#fbbf24; --code-keyword:#8fa4e0; --code-type:#5fc9c0;
  --exercise-bg:#fff7e6; --exercise-border:#e8a63d; --exercise-accent:#a66b0a; --bg-sunken:#eef2f6;
  --lv1:#e11d48; --lv2:#f59e0b; --lv3:#10b981; --lv4:#0d9488;
  line-height:1.65;
}

/* ---------------------------------------------------------------- nagłówek (w granatowym pasie strony) */
.course-hero .lead{max-width:640px}
.course-hero h1{font-size:clamp(34px,5vw,56px)}
.course-progress{margin-top:26px;max-width:640px}
.cp-bar{display:flex;height:10px;overflow:hidden;border-radius:999px;background:rgba(255,255,255,.14)}
.cp-bar i{display:block;height:100%;transition:width .3s ease}
.cp-bar i.l1{background:var(--lv1)} .cp-bar i.l2{background:var(--lv2)} .cp-bar i.l3{background:var(--lv3)} .cp-bar i.l4{background:var(--lv4)}
.cp-legend{display:flex;flex-wrap:wrap;gap:6px 16px;margin:10px 0 0;color:#cbd5e1;font-size:13px}
.cp-legend span::before{content:"";display:inline-block;width:9px;height:9px;margin-right:6px;border-radius:50%;background:currentColor;vertical-align:baseline}
.cp-legend .l1::before{color:var(--lv1)} .cp-legend .l2::before{color:var(--lv2)} .cp-legend .l3::before{color:var(--lv3)} .cp-legend .l4::before{color:var(--lv4)} .cp-legend .l0::before{color:#64748b}
.cp-actions{display:flex;flex-wrap:wrap;align-items:center;gap:12px;margin-top:16px}
.cp-btn{display:inline-flex;align-items:center;min-height:42px;padding-block:8px;line-height:1.3;border:1px solid var(--accent-light);border-radius:11px;background:transparent;color:#fff;padding:0 18px;font:700 14px inherit;text-decoration:none;cursor:pointer}
.cp-btn:hover{background:rgba(255,255,255,.1)}
.cp-btn.primary{border-color:transparent;background:#fff;color:var(--navy)}
.cp-btn.primary:hover{background:var(--accent-light)}
.cp-hint{color:#94a3b8;font-size:13px}

/* ---------------------------------------------------------------- układ: spis treści + treść */
.course-layout{display:grid;grid-template-columns:292px minmax(0,1fr);gap:32px;align-items:start;padding-block:36px 90px}
.course-main{min-width:0}
.course-toc{position:sticky;top:16px;max-height:calc(100vh - 32px);overflow-y:auto;border:1px solid var(--line);border-radius:18px;background:#fff;padding:18px 14px;box-shadow:var(--shadow);scrollbar-width:thin}
.toc-title{margin:0 8px 12px;font-size:14px;font-weight:800}
.toc-part{margin-bottom:14px}
.toc-part-head{display:flex;align-items:center;gap:8px;margin:0 8px 6px;color:var(--part-color,var(--muted));font:700 11px ui-monospace,monospace;letter-spacing:.08em;text-transform:uppercase}
.toc-part-head .count{margin-left:auto;color:var(--muted);font-weight:600;letter-spacing:0}
.toc-list{list-style:none;margin:0;padding:0;display:grid;gap:1px}
.toc-list a{display:flex;align-items:center;gap:9px;border-radius:9px;padding:6px 8px;color:#475569;text-decoration:none;font-size:13.5px;line-height:1.35;transition:background .15s}
.toc-list a:hover{background:#f1f5f9;color:var(--ink)}
.toc-list a.active{background:var(--navy);color:#fff}
.toc-list a.is-task{font-weight:700}
.toc-list a .t{flex:1;min-width:0}
.toc-list a .flag{flex:none;color:#d97706;font-size:12px}
.toc-list a.active .flag{color:#fcd34d}
.lv-dot{flex:none;width:14px;height:14px;border-radius:50%;background:conic-gradient(var(--c,#cbd5e1) calc(var(--p,0) * 1%),#e2e8f0 0);box-shadow:inset 0 0 0 1.5px rgba(15,23,42,.12)}
.lv-dot.l1{--c:var(--lv1);--p:25} .lv-dot.l2{--c:var(--lv2);--p:50} .lv-dot.l3{--c:var(--lv3);--p:75} .lv-dot.l4{--c:var(--lv4);--p:100}
.toc-list a.active .lv-dot{box-shadow:inset 0 0 0 1.5px rgba(255,255,255,.55)}
.toc-extra{border-top:1px solid var(--line);padding-top:10px}
.toc-legend{margin:12px 8px 0;color:var(--muted);font-size:11.5px;line-height:1.5}

.course-toc-mobile{display:none;margin-bottom:20px;border:1px solid var(--line);border-radius:14px;background:#fff;box-shadow:var(--shadow)}
.course-toc-mobile summary{display:flex;justify-content:space-between;padding:14px 16px;font-weight:700;cursor:pointer;list-style:none}
.course-toc-mobile summary::-webkit-details-marker{display:none}
.course-toc-mobile>[data-toc]{max-height:60vh;overflow-y:auto;padding:0 10px 14px}

/* ---------------------------------------------------------------- treść */
.intro-card{margin-bottom:28px;border:1px solid var(--line);border-radius:18px;background:#fff;padding:24px clamp(18px,4vw,34px);box-shadow:var(--shadow)}

.intro-card>:last-child{margin-bottom:0}

.course-main pre,.course-main .code-panel,.course-main table{max-width:100%}

/* nagłówek części: ten sam wygląd w obu kursach */
section.part-intro,.part-divider{position:relative;margin:48px 0 22px;border:0;border-bottom:2px solid var(--part-color,var(--line));border-radius:0;background:none;padding:0 0 14px;overflow:visible}
section.part-intro:first-of-type,.part-divider:first-of-type{margin-top:8px}
section.part-intro .part-label,.part-divider .part-label{display:inline-flex;align-items:center;margin:0 0 8px;border-radius:999px;background:color-mix(in srgb,var(--part-color) 13%,#fff);padding:3px 12px;color:var(--part-color);font:700 11.5px ui-monospace,monospace;letter-spacing:.08em;text-transform:uppercase}
section.part-intro h2,.part-divider h2{margin:0;font-size:clamp(22px,2.8vw,30px);font-weight:800;letter-spacing:-.02em;line-height:1.2}
section.part-intro p,.part-divider p:not(.part-label){margin:8px 0 0;color:var(--muted)}
.part-divider .part-index{display:none}

/* karta lekcji */
article.lesson,section.lesson:not(.task){position:relative;margin-bottom:22px;scroll-margin-top:16px;border:1px solid var(--line);border-radius:18px;background:#fff;padding:clamp(20px,4vw,34px);box-shadow:var(--shadow)}
section.lesson.task{margin-bottom:28px;scroll-margin-top:16px;border:0;background:none;padding:0}
.lesson-head{display:flex;align-items:flex-start;gap:16px;margin-bottom:14px}
.lesson-top{display:flex;align-items:center;gap:16px;min-width:0}
.lesson-badge,.lesson-number{flex:none;display:grid;place-items:center;width:52px;height:52px;border-radius:14px;background:var(--part-color,var(--navy));color:#fff;font:800 22px/1 Inter,system-ui,sans-serif;box-shadow:var(--shadow)}
.lesson-number svg{width:22px;height:22px;stroke:#fff}
.lesson-titlewrap,.lesson-top-text{min-width:0;flex:1}
.lesson-eyebrow{margin:0 0 4px;color:var(--part-color,var(--muted));font:700 11.5px ui-monospace,monospace;letter-spacing:.07em;text-transform:uppercase}
article.lesson h3,section.lesson h3{margin:0;font-size:clamp(20px,2.4vw,26px);font-weight:800;letter-spacing:-.02em;line-height:1.25}
section.lesson>p,section.lesson>ul,section.lesson>ol{margin:0 0 14px}
section.lesson ul,section.lesson ol{padding-left:1.3rem}
section.lesson li{margin-bottom:.35rem}
h4.subhead{margin:1.4em 0 .5em;font-size:17px;font-weight:700}

/* kod */
code{font-family:var(--font-mono);font-variant-ligatures:none}
:not(pre)>code{overflow-wrap:anywhere;border-radius:5px;background:var(--accent-soft);padding:.1em .38em;color:var(--navy2);font-size:.88em}
pre{position:relative;margin:0 0 16px;overflow-x:auto;border-radius:12px;background:var(--code-bg);padding:15px 18px;color:var(--code-text);font-size:13.5px;line-height:1.6;box-shadow:var(--shadow)}
pre code{background:none;padding:0;color:inherit;font-size:inherit}
.code-panel{margin:16px 0;overflow:hidden;border:1px solid var(--code-head);border-radius:12px;box-shadow:var(--shadow)}
.code-panel pre{margin:0;border-radius:0;box-shadow:none}
.code-panel-head{display:flex;align-items:center;justify-content:space-between;background:var(--code-head);padding:6px 12px;color:var(--code-comment);font:600 11px ui-monospace,monospace;letter-spacing:.05em;text-transform:uppercase}
.copy-btn{display:inline-flex;align-items:center;gap:5px;border:1px solid rgba(255,255,255,.18);border-radius:7px;background:rgba(255,255,255,.06);padding:3px 10px;color:var(--code-text);font:600 11.5px Inter,system-ui,sans-serif;cursor:pointer}
.copy-btn:hover{background:rgba(255,255,255,.14)}
.copy-btn svg{width:12px;height:12px}
.copy-btn.copied{border-color:#34d399;color:#6ee7b7}
pre>.copy-btn{position:absolute;top:8px;right:8px;opacity:0;transition:opacity .15s}
pre:hover>.copy-btn,pre>.copy-btn:focus-visible{opacity:1}
.tok-kw{color:var(--code-keyword);font-weight:600}.tok-str{color:var(--code-string)}.tok-com,.code-comment{color:var(--code-comment);font-style:italic}.tok-type{color:var(--code-type)}

/* ---------------------------------------------------------------- komponenty treści wspólne dla kursów */
.callout{margin:16px 0;border:1px solid;border-radius:12px;padding:14px 16px;font-size:15px}
.callout p:last-child{margin-bottom:0}
.callout-head{display:flex;align-items:center;gap:7px;margin-bottom:6px;font-size:12.5px;font-weight:800;letter-spacing:.05em;text-transform:uppercase}
.callout-bad{background:var(--bad-bg);border-color:var(--bad)} .callout-bad .callout-head{color:var(--bad)}
.callout-good{background:var(--good-bg);border-color:var(--good)} .callout-good .callout-head{color:var(--good)}
.callout-note{background:var(--surface-alt);border-color:var(--border)} .callout-note .callout-head{color:var(--text-muted)}

.exercise{margin-top:18px;border:1px solid var(--exercise-border);border-radius:12px;background:var(--exercise-bg);padding:16px 20px;box-shadow:var(--shadow)}
.exercise-label{display:flex;align-items:center;gap:7px;margin-bottom:8px;color:var(--exercise-accent);font-size:11.5px;font-weight:800;letter-spacing:.07em;text-transform:uppercase}
.exercise-label::before{content:"";width:14px;height:14px;flex:none;background:currentColor;-webkit-mask:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'><path d='M9 18h6'/><path d='M10 22h4'/><path d='M12 2a7 7 0 0 0-4 12.7V17h8v-2.3A7 7 0 0 0 12 2Z'/></svg>") center/contain no-repeat;mask:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'><path d='M9 18h6'/><path d='M10 22h4'/><path d='M12 2a7 7 0 0 0-4 12.7V17h8v-2.3A7 7 0 0 0 12 2Z'/></svg>") center/contain no-repeat}
.exercise p{margin:0 0 .6rem}
.exercise details{margin-top:.3rem}
.exercise summary{color:var(--exercise-accent);font-size:14px;font-weight:700;cursor:pointer}
.exercise .answer{margin-top:.6rem;border-top:1px dashed var(--exercise-border);padding-top:.6rem;font-size:15px}

/* zadania praktyczne (styl CKE) */
.task-card{position:relative;overflow:hidden;border:1px solid var(--border);border-radius:18px;background:#fff;box-shadow:0 12px 28px -12px rgba(15,23,42,.18)}
.task-card::before{content:"";position:absolute;inset:0 auto 0 0;width:5px;background:var(--part-color,var(--navy))}
.task-inner{padding:24px clamp(18px,3vw,30px) 26px 30px}
.task-meta{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:16px}
.task-meta span{border:1px solid var(--border);border-radius:999px;background:var(--bg-sunken);padding:3px 11px;color:var(--text-muted);font-size:12px;font-weight:600}
.task-meta span b{color:var(--text)}
.task-card h4{display:flex;align-items:center;gap:8px;margin:22px 0 8px;font-size:16px;font-weight:700}
.task-card h4::before{content:"";width:8px;height:8px;flex:none;border-radius:2px;background:var(--part-color,var(--navy))}
.task-card h4:first-of-type{margin-top:0}
.task-card p{margin:0 0 .75rem}
ul.cke{list-style:none;margin:0 0 .9rem;padding-left:1.35rem}
ul.cke li{position:relative;margin-bottom:.4rem}
ul.cke li::before{content:"‒";position:absolute;left:-1.35rem;color:var(--text-muted)}
ul.cke ul.cke{margin:.35rem 0 .2rem}
.task-card details.hints{margin-top:18px;border:1px dashed var(--border-strong);border-radius:10px;background:var(--bg-sunken);padding:11px 15px}
.task-card details.hints summary{color:var(--navy2);font-size:14px;font-weight:700;cursor:pointer}
.task-card details.hints ul{margin:.6rem 0 0;padding-left:1.2rem;font-size:14.5px}
.task-card .bonus{margin-top:16px;border:1px solid var(--border);border-radius:10px;background:var(--accent-soft);padding:12px 15px;font-size:14.5px}
.task-card .bonus b{color:var(--navy2)}
.task-note{margin-top:14px;color:var(--text-muted);font-size:14px}

/* ściągawka */
.ref-group-title{margin:28px 0 11px;font-size:17px;font-weight:700}
.ref-wrap{margin-bottom:8px;overflow-x:auto;border:1px solid var(--border);border-radius:12px;box-shadow:var(--shadow)}
table.ref-table{width:100%;border-collapse:collapse;background:#fff;font-size:14px}
table.ref-table th{border-bottom:1px solid var(--border);background:var(--bg-sunken);padding:10px 13px;color:var(--text-muted);font:700 11px ui-monospace,monospace;letter-spacing:.06em;text-align:left;text-transform:uppercase;white-space:nowrap}
table.ref-table td{border-bottom:1px solid var(--border);padding:11px 13px;vertical-align:top}
table.ref-table tr:last-child td{border-bottom:0}
table.ref-table tbody tr:hover{background:var(--bg-sunken)}
table.ref-table td:first-child{font-weight:600;white-space:nowrap}
table.ref-table td code{white-space:nowrap}
table.ref-table a.doc-link{color:var(--part-g,var(--navy));font-size:14px;font-weight:700;text-decoration:none;white-space:nowrap}
table.ref-table a.doc-link:hover{text-decoration:underline}

/* ---------------------------------------------------------------- ocena zrozumienia */
.understand{margin-top:26px;border:1px solid var(--line);border-radius:14px;background:linear-gradient(180deg,#f8fafc,#f1f5f9);padding:16px 18px}
.understand-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:10px}
.understand-head strong{font-size:14.5px}
.understand-saved{color:var(--good);font-size:12.5px;font-weight:700;opacity:0;transition:opacity .25s}
.understand-saved.on{opacity:1}
.understand-levels{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
.lv{display:flex;flex-direction:column;align-items:center;gap:2px;border:1.5px solid var(--line);border-radius:12px;background:#fff;padding:10px 6px;color:#475569;font:600 12.5px/1.25 Inter,system-ui,sans-serif;text-align:center;cursor:pointer;transition:border-color .15s,background .15s,transform .1s}
.lv .ico{font-size:22px;line-height:1.1}
.lv:hover{border-color:#94a3b8;transform:translateY(-1px)}
.lv[aria-checked="true"]{color:var(--ink);font-weight:800}
.lv.l1[aria-checked="true"]{border-color:var(--lv1);background:#fff1f2}
.lv.l2[aria-checked="true"]{border-color:var(--lv2);background:#fffbeb}
.lv.l3[aria-checked="true"]{border-color:var(--lv3);background:#ecfdf5}
.lv.l4[aria-checked="true"]{border-color:var(--lv4);background:#f0fdfa}
.lv:disabled,.chip:disabled{cursor:default}
.lv:disabled:hover{transform:none;border-color:var(--line)}
.understand-actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}
.chip{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);border-radius:999px;background:#fff;padding:6px 13px;color:#475569;font:600 13px Inter,system-ui,sans-serif;text-decoration:none;cursor:pointer}
.chip:hover{border-color:#94a3b8;color:var(--ink)}
.chip[aria-pressed="true"]{border-color:#f59e0b;background:#fffbeb;color:#92400e}
.chip.practice{border-color:var(--navy);background:var(--navy);color:#fff}
.chip.practice:hover{background:var(--navy2);color:#fff}
.understand-note{margin-top:12px}
.understand-note textarea{display:block;width:100%;min-height:84px;resize:vertical;border:1px solid var(--line);border-radius:10px;background:#fff;padding:10px 12px;color:var(--ink);font:inherit;font-size:14px}
.understand-note small{display:block;margin-top:4px;color:var(--muted)}
.understand.guest{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px;color:#475569;font-size:14px}
.understand.guest a{font-weight:700}

/* ---------------------------------------------------------------- pasek czytania i "do góry" */
#reading-progress{position:fixed;top:0;left:0;right:0;z-index:60;height:3px;pointer-events:none}
#reading-progress-bar{width:0;height:100%;background:linear-gradient(90deg,var(--brand),#10b981);transition:width .1s linear}
#back-to-top{position:fixed;right:20px;bottom:20px;z-index:50;display:grid;place-items:center;width:44px;height:44px;border:0;border-radius:50%;background:var(--navy);color:#fff;box-shadow:0 8px 22px rgba(15,23,42,.3);font-size:18px;cursor:pointer;opacity:0;transform:translateY(8px);pointer-events:none;transition:opacity .2s,transform .2s}
#back-to-top.show{opacity:1;transform:none;pointer-events:auto}

a:focus-visible,button:focus-visible,summary:focus-visible,textarea:focus-visible{outline:2px solid var(--brand);outline-offset:2px}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}

@media(max-width:960px){
  .course-layout{grid-template-columns:1fr;gap:0;padding-top:24px}
  .course-toc{display:none}
  .course-toc-mobile{display:block}
}
@media(max-width:600px){
  .understand-levels{grid-template-columns:1fr 1fr}
  .lesson-badge,.lesson-number{width:44px;height:44px;font-size:18px}
  .course-hero .stats{max-width:none}
}