/* =============================================================
   "Kubernetes на практике" — shared stylesheet
   Visual idea: a chart room. A dark wayfinding console (chart-nav)
   holds the plotted course through the lessons; the reading surface
   is a warm paper page, like a chart or logbook laid on the table.
   Every lesson/reference page links this file — edit once, applies
   everywhere. Component partners: nav.js (route), quiz.js, copy.js.
   ============================================================= */

:root {
  --ink: #0e1e29;
  --ink-2: #16303f;
  --ink-line: #2c4657;
  --ink-text: #c9d8e2;
  --ink-text-strong: #f3f7f9;

  --paper: #f5efe0;
  --paper-card: #fbf7ec;
  --paper-line: #d9cca8;
  --text: #241f18;
  --text-muted: #6b6252;

  --brass: #a97a30;
  --brass-strong: #8a611f;
  --pine: #3c6e58;
  --rust: #9c4a30;

  --font-display: "Fraunces", "Iowan Old Style", Georgia, serif;
  --font-body: "Source Serif 4", "Iowan Old Style", Georgia, serif;
  --font-mono: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;

  --sidebar-w: 280px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #1c1712;
    --paper-card: #241e17;
    --paper-line: #3a3226;
    --text: #ece4d3;
    --text-muted: #b6a98f;
    --brass: #c99a4c;
    --brass-strong: #e0b567;
    --pine: #6aab8b;
    --rust: #d17e5f;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
}

::selection { background: var(--brass); color: var(--ink); }

a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 2px; }

:focus-visible {
  outline: 2px solid var(--brass);
  outline-offset: 2px;
}

/* ---------- Shell: sidebar + page ---------- */

.shell {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  align-items: stretch;
}
@media (min-width: 900px) {
  .shell { flex-direction: row; }
}

.chart-nav {
  width: 100%;
  background: var(--ink);
  color: var(--ink-text);
  padding: 1.5rem 1.5rem 1.4rem;
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
}
@media (min-width: 900px) {
  .chart-nav {
    flex: 0 0 var(--sidebar-w);
    width: var(--sidebar-w);
    padding: 1.9rem 1.6rem 1.6rem;
    gap: 1.6rem;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
  }
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  text-decoration: none;
  color: inherit;
}
.brand-mark { color: var(--brass); flex: none; }
.brand-title {
  display: block;
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 600;
  font-size: 1.08rem;
  line-height: 1.2;
  color: var(--ink-text-strong);
}

/* Mobile: native <details> collapses the route; desktop unwraps it
   via display:contents so it always reads as an open sidebar list. */
.route-toggle { border: none; }
.route-summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-text-strong);
  padding: 0.6rem 0.1rem;
  border-top: 1px solid var(--ink-line);
  border-bottom: 1px solid var(--ink-line);
}
.route-summary::-webkit-details-marker { display: none; }
.route-summary::after {
  content: "\2304";
  font-family: var(--font-mono);
  color: var(--brass);
  transition: transform 0.2s ease;
}
details[open] > .route-summary::after { transform: rotate(180deg); }
.route-progress { color: var(--brass); opacity: 1; }

#course-route { margin-top: 0.9rem; }

@media (min-width: 900px) {
  .route-toggle { display: contents; }
  .route-summary { display: none; }
  #course-route { margin-top: 0.2rem; }
}

.route {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.route-track {
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background-image: repeating-linear-gradient(to bottom, var(--ink-line) 0 4px, transparent 4px 9px);
}
.route-track-charted {
  position: absolute;
  left: 0;
  top: 0;
  width: 2px;
  height: 0%;
  background: var(--brass);
  transition: height 0.9s cubic-bezier(0.2, 0.7, 0.3, 1);
}
@media (prefers-reduced-motion: reduce) {
  .route-track-charted { transition: none; }
}

.route-stop {
  position: relative;
  padding: 0.5rem 0 0.5rem 1.75rem;
  min-height: 1.6rem;
}

.route-dot {
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--paper);
  border: 1.5px solid var(--brass);
}
.route-stop.is-locked .route-dot {
  background: transparent;
  border: 1.5px dashed var(--ink-line);
}
.route-stop.is-current .route-dot {
  background: var(--brass);
  box-shadow: 0 0 0 3px rgba(169, 122, 48, 0.28);
}

.route-num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--ink-text);
  opacity: 0.55;
  margin-right: 0.55rem;
}
.route-stop.is-current .route-num { color: var(--brass); opacity: 1; }

.route-label {
  font-family: var(--font-body);
  font-size: 0.92rem;
  line-height: 1.3;
}
a.route-label { color: var(--ink-text); text-decoration: none; }
a.route-label:hover { color: var(--ink-text-strong); text-decoration: underline; }
span.route-label { color: var(--ink-text-strong); font-weight: 600; }
.route-stop.is-locked .route-label { color: var(--ink-text); opacity: 0.45; }

.route-duration {
  display: block;
  margin-top: 0.1rem;
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 0.72rem;
  opacity: 0.55;
}

.route-soon {
  display: block;
  margin-left: 1.75rem;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-text);
  opacity: 0.35;
}

.ref-section {
  padding-top: 1rem;
  border-top: 1px solid var(--ink-line);
}
.ref-heading {
  margin: 0 0 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-text-strong);
}
.ref-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.ref-list a {
  color: var(--ink-text);
  text-decoration: none;
  font-family: var(--font-body);
  font-size: 0.92rem;
}
.ref-list a:hover { color: var(--brass); }
.ref-locked {
  color: var(--ink-text);
  opacity: 0.45;
  font-family: var(--font-body);
  font-size: 0.92rem;
}
.ref-soon {
  margin-left: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--ink-text);
  opacity: 0.35;
}

.chart-footer {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--ink-line);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}
.chart-footer a { color: var(--ink-text); text-decoration: none; }
.chart-footer a:hover { color: var(--brass); }

.chart-footer-group { display: flex; flex-direction: column; gap: 0.35rem; }
.chart-footer-label {
  font-size: 0.66rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--ink-text);
  opacity: 0.5;
}

.chart-channel {
  display: flex;
  align-items: center;
  gap: 0.55rem;
}
.chart-channel-avatar {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  object-fit: cover;
  border: 1.5px solid var(--brass);
  flex: none;
}
.chart-channel span { line-height: 1.3; }

/* ---------- Page (reading surface) ---------- */

.page-frame {
  flex: 1;
  min-width: 0;
  background: var(--paper);
  color: var(--text);
  padding: 3.4rem 1.5rem 6rem;
}

.page {
  max-width: 40rem;
  margin: 0 auto;
}

.kicker {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--brass-strong);
  margin: 0 0 0.6rem;
}

h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.9rem, 1.55rem + 1.4vw, 2.55rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 0 0 0.9rem;
}

h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.42rem;
  margin: 2.6rem 0 0.9rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--paper-line);
}

h3 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.12rem;
  margin: 1.7rem 0 0.5rem;
}

p { margin: 0 0 1.05rem; font-size: 1.05rem; line-height: 1.7; }

.lede {
  font-family: var(--font-body);
  font-style: italic;
  font-size: 1.18rem;
  line-height: 1.55;
  color: var(--text-muted);
  margin-bottom: 2.2rem;
}

.page a { color: var(--brass-strong); text-decoration-line: underline; text-decoration-color: color-mix(in srgb, var(--brass) 45%, transparent); }
.page a:hover { text-decoration-color: currentColor; }

ul, ol.steps { padding-left: 1.3rem; }
ul li, .steps li { margin-bottom: 0.6rem; line-height: 1.65; }
.steps li { margin-bottom: 1rem; }

code, pre, kbd { font-family: var(--font-mono); font-size: 0.9em; }

code {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  padding: 0.1em 0.4em;
  border-radius: 4px;
}

pre {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: 8px;
  padding: 1rem 1.1rem;
  overflow-x: auto;
  line-height: 1.55;
}
pre code { background: none; border: none; padding: 0; }

blockquote {
  margin: 1.3rem 0;
  padding: 0.2rem 1.1rem;
  border-left: 3px solid var(--brass);
  color: var(--text-muted);
  font-style: italic;
}

.callout {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-left: 3px solid var(--brass);
  border-radius: 4px 10px 10px 4px;
  padding: 1.05rem 1.25rem;
  margin: 1.7rem 0;
}
.callout .callout-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  font-weight: 600;
  color: var(--brass-strong);
  display: block;
  margin-bottom: 0.45rem;
}

.diagram-figure {
  margin: 1.8rem 0;
  padding: 1.1rem 1.1rem 0.9rem;
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: 10px;
}
.diagram-figure svg {
  display: block;
  width: 100%;
  height: auto;
}
.diagram-figure figcaption {
  margin-top: 0.7rem;
  padding-top: 0.7rem;
  border-top: 1px solid var(--paper-line);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--text-muted);
  text-align: center;
}
.diagram-title { font-family: var(--font-mono); font-size: 12px; font-weight: 600; letter-spacing: 0.02em; }
.diagram-sub { font-family: var(--font-body); font-size: 11.5px; }
.diagram-note { font-family: var(--font-mono); font-size: 10.5px; letter-spacing: 0.02em; }
.callout.win { border-left-color: var(--pine); }
.callout.win .callout-label { color: var(--pine); }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.3rem 0;
  font-size: 0.95rem;
}
th, td {
  text-align: left;
  padding: 0.55rem 0.7rem;
  border-bottom: 1px solid var(--paper-line);
  vertical-align: top;
}
th {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  font-weight: 600;
}

nav.lesson-nav {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  margin: 3.2rem 0 0;
  padding-top: 1.1rem;
  border-top: 1px solid var(--paper-line);
  color: var(--text-muted);
}

footer.sources {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--paper-line);
  font-size: 0.88rem;
  color: var(--text-muted);
}

.lesson-help {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--text-muted);
  background: var(--paper-card);
  border-left: 2px solid var(--brass);
  border-radius: 4px;
  padding: 0.65rem 0.9rem;
  margin: 0 0 1.8rem;
}
.lesson-help a { color: var(--brass-strong); }

/* ---------- Copy-to-clipboard (assets/copy.js) ---------- */

.pre-wrap { position: relative; }
.pre-wrap .copy-btn {
  position: absolute;
  top: 0.55rem;
  right: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  padding: 0.28rem 0.6rem;
  border-radius: 5px;
  border: 1px solid var(--paper-line);
  background: var(--paper);
  color: var(--text-muted);
  cursor: pointer;
  opacity: 0.75;
}
.pre-wrap:hover .copy-btn { opacity: 1; }
.pre-wrap .copy-btn:hover { color: var(--brass-strong); border-color: var(--brass); }
.pre-wrap .copy-btn.copied { color: var(--pine); border-color: var(--pine); opacity: 1; }

code.cmd, code.copyable {
  cursor: pointer;
  border-color: var(--paper-line);
}
code.copyable:hover { border-color: var(--brass); color: var(--brass-strong); }
code.copyable.copied-flash {
  border-color: var(--pine);
  color: var(--pine);
  background: color-mix(in srgb, var(--pine) 16%, var(--paper-card));
}

/* ---------- Quiz (assets/quiz.js) ---------- */

.quiz {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: 10px;
  padding: 1.15rem 1.3rem 1.35rem;
  margin: 1.8rem 0;
}
.quiz-question {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 0.85rem;
}
.quiz-option {
  display: block;
  font-family: var(--font-body);
  font-size: 0.98rem;
  margin: 0.45rem 0;
  cursor: pointer;
}
.quiz-option input { margin-right: 0.55rem; accent-color: var(--brass); }

.quiz-recall input[type="text"] {
  width: 100%;
  font-family: var(--font-mono);
  font-size: 0.94rem;
  padding: 0.55rem 0.65rem;
  border: 1px solid var(--paper-line);
  border-radius: 6px;
  background: var(--paper);
  color: var(--text);
}

.quiz-check {
  margin-top: 0.95rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 0.48rem 1.05rem;
  border-radius: 6px;
  border: 1px solid var(--brass);
  background: transparent;
  color: var(--brass-strong);
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}
.quiz-check:hover { background: var(--brass); color: var(--paper); }

.quiz-feedback {
  margin-top: 0.85rem;
  font-family: var(--font-body);
  font-size: 0.92rem;
  padding: 0.6rem 0.85rem;
  border-radius: 6px;
}
.quiz-feedback.correct { background: color-mix(in srgb, var(--pine) 15%, transparent); color: var(--pine); }
.quiz-feedback.incorrect { background: color-mix(in srgb, var(--rust) 15%, transparent); color: var(--rust); }

@media print {
  .chart-nav { display: none; }
  .page-frame { padding: 0; }
  body { background: #fff; font-size: 11pt; }
  .quiz-check, .copy-btn { display: none; }
  .page a { color: inherit; }
}