/* AI Craft Campus design system.
   System fonts only (no downloads, no layout shift). Colors are tokens with a
   dark theme. Mobile reading text is 18px / 1.8; nothing is under 14px. */

:root {
  --paper: #fbfaf7;
  --surface: #ffffff;
  --surface-2: #f3f1ea;
  --ink: #14213d;
  --ink-soft: #2b3752;
  --muted: #555e6e;
  --line: #e2ddd1;
  --accent: #a34a12;          /* copper: links, buttons (5.6:1 on white) */
  --accent-ink: #ffffff;
  --accent-soft: #fbeee4;
  --focus: #1d4ed8;
  --beginner: #0f766e;  --beginner-soft: #e6f4f1;
  --business: #92400e;  --business-soft: #fbf0e1;
  --advanced: #4338ca;  --advanced-soft: #eceafb;
  --ok: #166534;  --ok-soft: #e7f5ea;
  --bad: #b42318; --bad-soft: #fdecea;
  --code-bg: #f4f2ec;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(20, 33, 61, .06), 0 6px 20px rgba(20, 33, 61, .06);
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #0e1524; --surface: #151f33; --surface-2: #1b2740; --ink: #eef1f6; --ink-soft: #d5dbe6; --muted: #a9b3c4; --line: #2a3752;
    --accent: #f0a46b; --accent-ink: #1b1206; --accent-soft: #33241a; --focus: #93b4ff;
    --beginner: #5eead4; --beginner-soft: #10302d; --business: #fbbf6a; --business-soft: #33260f; --advanced: #b4bcfd; --advanced-soft: #232552;
    --ok: #86efac; --ok-soft: #12301c; --bad: #fca5a5; --bad-soft: #3a1616; --code-bg: #111a2b;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 6px 20px rgba(0, 0, 0, .25);
    color-scheme: dark;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 88px; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 17px/1.65 var(--sans); }
img, svg { max-width: 100%; height: auto; }
a { color: var(--accent); text-underline-offset: .18em; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; border-radius: 4px; }
h1, h2, h3, h4, h5, h6 { font-family: var(--serif); color: var(--ink); line-height: 1.2; letter-spacing: -.01em; }
h1 { font-size: clamp(2rem, 1.4rem + 2.6vw, 3.1rem); margin: .2em 0 .35em; }
h2 { font-size: clamp(1.5rem, 1.25rem + 1vw, 2rem); margin: 1.6em 0 .5em; }
h3 { font-size: 1.3rem; margin: 1.4em 0 .4em; }
h4 { font-size: 1.2rem; margin: 1.3em 0 .35em; }
/* Subheadings inside lesson text (### in a lesson body renders as h5): never smaller than body text. */
h5 { font-size: 1.1rem; margin: 1.2em 0 .3em; }
h6 { font-size: 1rem; margin: 1.1em 0 .3em; }
p, ul, ol, dl { margin: 0 0 1em; }
code { font-family: var(--mono); font-size: .92em; background: var(--code-bg); padding: .1em .35em; border-radius: 5px; }
hr { border: 0; border-top: 1px solid var(--line); margin: 2em 0; }

.wrap { width: min(1160px, 100% - 32px); margin-inline: auto; }
.narrow { max-width: 760px; }
.skip-link { position: absolute; left: -9999px; top: 8px; z-index: 10; background: var(--surface); padding: 10px 14px; border-radius: 8px; }
.skip-link:focus { left: 12px; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 5; background: color-mix(in srgb, var(--paper) 92%, transparent); backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--line); }
.header-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 68px; }
.logo { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; font-family: var(--serif); font-weight: 700; font-size: 1.25rem; }
.logo-text span { color: var(--accent); }
.logo-mark { flex: none; }
.logo-bg { fill: var(--ink); }
.logo-book { fill: none; stroke: var(--paper); stroke-width: 2; stroke-linejoin: round; }
.logo-spine { stroke: var(--paper); stroke-width: 2; }
.logo-node { fill: #f0a46b; }
.logo-link { stroke: #f0a46b; stroke-width: 1.4; }
.admin-badge { font: 600 14px/1 var(--sans); background: var(--advanced-soft); color: var(--advanced); padding: 6px 10px; border-radius: 999px; margin-left: 6px; }
.site-nav ul { list-style: none; margin: 0; padding: 0; }
.nav-inline { display: flex; gap: 4px; }
.nav-inline a, .nav-menu a { display: block; padding: 10px 12px; border-radius: 10px; color: var(--ink-soft); text-decoration: none; font-weight: 600; font-size: 16px; }
.nav-inline a:hover, .nav-menu a:hover { background: var(--surface-2); color: var(--ink); }
.nav-inline a[aria-current="page"], .nav-menu a[aria-current="page"] { color: var(--accent); background: var(--accent-soft); }
.nav-menu { display: none; position: relative; }
.nav-menu summary { list-style: none; cursor: pointer; font-weight: 700; font-size: 16px; padding: 10px 16px; min-height: 44px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); }
.nav-menu summary::-webkit-details-marker { display: none; }
.nav-menu ul { position: absolute; right: 0; top: calc(100% + 8px); width: min(280px, calc(100vw - 32px)); background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 8px; }
@media (max-width: 980px) { .nav-inline { display: none; } .nav-menu { display: block; } }

/* Buttons */
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 12px 22px; border-radius: 12px; border: 2px solid var(--accent); background: var(--accent); color: var(--accent-ink); font: 700 16px/1.2 var(--sans); text-decoration: none; cursor: pointer; }
.button:hover { filter: brightness(1.06); text-decoration: none; }
.button-quiet { background: transparent; color: var(--accent); }
.button-danger { background: transparent; color: var(--bad); border-color: var(--bad); }
.button[disabled] { opacity: .5; cursor: not-allowed; }
.link-button { background: none; border: 0; padding: 4px 2px; color: var(--accent); font: inherit; font-size: 15px; text-decoration: underline; cursor: pointer; min-height: 32px; }
.copy-button { margin: 8px 0 4px; min-height: 40px; padding: 8px 14px; border-radius: 10px; border: 1px solid var(--line); background: var(--surface); color: var(--ink-soft); font: 600 14px/1 var(--sans); cursor: pointer; }
.copy-button:hover { border-color: var(--accent); color: var(--accent); }

/* Hero and sections */
.hero { padding: 56px 0 40px; background: radial-gradient(ellipse at 85% 0%, var(--accent-soft), transparent 60%), radial-gradient(ellipse at 0% 100%, var(--advanced-soft), transparent 55%); border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; grid-template-columns: 1.25fr .9fr; gap: 40px; align-items: center; }
.hero h1 span { color: var(--accent); }
.eyebrow { font: 700 14px/1.3 var(--sans); text-transform: uppercase; letter-spacing: .08em; color: var(--accent); margin: 0 0 .4em; }
.lead { font-size: 1.15rem; color: var(--ink-soft); max-width: 62ch; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.hero-card, .panel, .course-card, .admin-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 24px; }
.hero-card-title { font: 700 1.15rem/1.3 var(--serif); margin-bottom: .6em; }
.section { padding: 48px 0; }
.section-alt { background: var(--surface-2); border-block: 1px solid var(--line); }
.section h2:first-child, .section .eyebrow + h2 { margin-top: 0; }
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.panel h3 { margin-top: 0; }
.check-list { list-style: none; padding: 0; }
.check-list li { position: relative; padding-left: 30px; margin-bottom: .55em; }
.check-list li::before { content: ""; position: absolute; left: 4px; top: .5em; width: 14px; height: 8px; border-left: 3px solid var(--accent); border-bottom: 3px solid var(--accent); transform: rotate(-45deg); }
@media (max-width: 860px) { .hero-grid, .two-col { grid-template-columns: minmax(0, 1fr); } .hero { padding-top: 36px; } }

/* Paths */
.path-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.path-card { border-radius: var(--radius); padding: 24px; border: 1px solid var(--line); border-top: 6px solid; background: var(--surface); }
.path-card h3 { margin-top: .2em; }
.path-beginner { border-top-color: var(--beginner); } .path-business { border-top-color: var(--business); } .path-advanced { border-top-color: var(--advanced); }
.path-letter { font: 700 14px/1 var(--sans); text-transform: uppercase; letter-spacing: .08em; margin: 0; }
.path-beginner .path-letter { color: var(--beginner); } .path-business .path-letter { color: var(--business); } .path-advanced .path-letter { color: var(--advanced); }
@media (max-width: 860px) { .path-grid { grid-template-columns: minmax(0, 1fr); } }
.chip { display: inline-flex; align-items: center; gap: 6px; font: 700 14px/1 var(--sans); padding: 6px 10px; border-radius: 999px; }
.chip-letter { display: inline-grid; place-items: center; width: 22px; height: 22px; border-radius: 50%; font-size: 14px; color: var(--surface); }
.chip-beginner { background: var(--beginner-soft); color: var(--beginner); } .chip-beginner .chip-letter { background: var(--beginner); }
.chip-business { background: var(--business-soft); color: var(--business); } .chip-business .chip-letter { background: var(--business); }
.chip-advanced { background: var(--advanced-soft); color: var(--advanced); } .chip-advanced .chip-letter { background: var(--advanced); }

/* Courses and lesson lists */
.page-head { padding: 28px 0 8px; }
.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; padding: 0; margin: 0 0 14px; font-size: 15px; color: var(--muted); }
.crumbs li + li::before { content: "/"; margin-right: 6px; color: var(--line); }
.crumbs a { color: var(--muted); }
.course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px; padding-bottom: 48px; }
.course-card h2 { margin-top: .2em; } .course-card h2 a { color: var(--ink); text-decoration: none; }
.course-layout { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); gap: 40px; padding-bottom: 56px; }
.course-facts { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 8px 24px 16px; align-self: start; }
.course-facts h2 { font-size: 1.2rem; margin: 1.1em 0 .4em; }
@media (max-width: 860px) { .course-layout { grid-template-columns: minmax(0, 1fr); } }
.lesson-list { list-style: none; padding: 0; counter-reset: none; display: grid; gap: 12px; }
.lesson-item { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; }
.lesson-item a { text-decoration: none; display: block; }
.lesson-num { display: block; font: 700 14px/1.3 var(--sans); color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.lesson-title { display: block; font: 700 1.2rem/1.3 var(--serif); color: var(--ink); margin: 2px 0 6px; }
.lesson-item a:hover .lesson-title { color: var(--accent); }
.lesson-item.is-planned { background: transparent; border-style: dashed; }
.lesson-item.is-planned .lesson-title { color: var(--muted); }
.lesson-item p { margin: 0 0 8px; color: var(--ink-soft); }
.lesson-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 10px; font-size: 15px; color: var(--muted); }
.status-pill { display: inline-block; font: 700 14px/1 var(--sans); padding: 6px 10px; border-radius: 999px; background: var(--surface-2); color: var(--muted); text-transform: none; }
.status-published, .status-live { background: var(--ok-soft); color: var(--ok); }
.status-draft { background: var(--accent-soft); color: var(--accent); }
.status-unpublished, .status-hidden { background: var(--bad-soft); color: var(--bad); }
.progress-flag { font-weight: 700; color: var(--ok); }
.course-progress, .lesson-progress { margin: 14px 0 6px; max-width: 520px; }
.bar { height: 10px; background: var(--surface-2); border: 1px solid var(--line); border-radius: 999px; overflow: hidden; }
.bar span { display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--beginner), var(--accent)); transition: width .3s; }
.progress-text, .course-progress p { font-size: 15px; line-height: 1.5; color: var(--muted); margin: 6px 0 0; }
.progress-text { min-height: 3em; }
@media (max-width: 600px) { .progress-text { min-height: 4.5em; } }

/* Lesson page */
.lesson-head { padding: 24px 0 6px; }
.lesson-layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 48px; align-items: start; }
.toc { position: sticky; top: 88px; font-size: 15px; }
.toc summary, .toc-title { font: 700 14px/1.3 var(--sans); text-transform: uppercase; letter-spacing: .06em; color: var(--muted); padding: 6px 0; margin: 0; }
.toc summary { cursor: pointer; min-height: 44px; display: flex; align-items: center; }
.toc-mobile { display: none; }
.toc ol { list-style: none; padding: 0; margin: 8px 0 14px; border-left: 2px solid var(--line); }
.toc a { display: block; padding: 6px 12px; color: var(--ink-soft); text-decoration: none; margin-left: -2px; border-left: 2px solid transparent; }
.toc a:hover, .toc a.is-current { color: var(--accent); border-left-color: var(--accent); }
.toc-course a { font-weight: 600; }
.prose { max-width: 72ch; min-width: 0; }
.prose ul, .prose ol { padding-left: 1.4em; }
.prose li { margin-bottom: .4em; }
.prose blockquote { margin: 1.2em 0; padding: 4px 20px; border-left: 4px solid var(--accent); background: var(--accent-soft); border-radius: 0 10px 10px 0; }
.lesson-section { padding-bottom: 12px; border-bottom: 1px solid var(--line); margin-bottom: 8px; }
.lesson-section:last-child { border-bottom: 0; }
.lesson-section > h2 { margin-top: 1.2em; }
.teaching h3:first-child { margin-top: 1em; }
.path-block { border-left: 5px solid; padding: 4px 0 4px 20px; margin: 18px 0; border-radius: 2px; }
.path-block.path-beginner { border-color: var(--beginner); } .path-block.path-business { border-color: var(--business); } .path-block.path-advanced { border-color: var(--advanced); }
.block-label { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: 15px; color: var(--muted); margin: 6px 0; }
.advanced { background: var(--advanced-soft); border: 1px solid color-mix(in srgb, var(--advanced) 30%, transparent); border-radius: var(--radius); padding: 8px 24px 20px; margin-top: 18px; }
.advanced h2 { color: var(--advanced); margin-top: .4em; }
.exercise { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 4px 20px 12px; margin: 14px 0; }
.expected { font-size: 16px; color: var(--ink-soft); }
pre.prompt, pre.code { white-space: pre-wrap; word-break: break-word; font: 15px/1.6 var(--mono); background: var(--code-bg); border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; margin: 10px 0 4px; }
pre.code { white-space: pre; overflow-x: auto; word-break: normal; }
pre.code code { background: none; padding: 0; font-size: inherit; }
.table-wrap { overflow-x: auto; margin: 1em 0; }
table { border-collapse: collapse; width: 100%; font-size: 16px; }
th, td { text-align: left; vertical-align: top; padding: 10px 12px; border-bottom: 1px solid var(--line); }
thead th { background: var(--surface-2); }
.demo { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 6px 22px 18px; margin: 18px 0; box-shadow: var(--shadow); }
.compare { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.compare-label { font: 700 14px/1.3 var(--sans); text-transform: uppercase; letter-spacing: .06em; margin: 10px 0 0; }
.compare-weak .compare-label { color: var(--bad); } .compare-strong .compare-label { color: var(--ok); }
@media (max-width: 700px) { .compare { grid-template-columns: minmax(0, 1fr); } }
.why { border-top: 1px dashed var(--line); margin-top: 12px; padding-top: 6px; }
.stepper ol { list-style: none; padding: 0; }
.step-count { font: 700 14px/1 var(--sans); color: var(--muted); margin: 8px 0 0; }
.stepper-controls { display: flex; gap: 10px; }
.reveal { border: 1px solid var(--line); border-radius: 10px; padding: 12px 16px; margin: 10px 0; background: var(--paper); }
.reveal summary { cursor: pointer; font-weight: 700; }
.myths { margin: 0; }
.myth { border: 1px solid var(--line); border-radius: 12px; padding: 14px 18px; margin: 12px 0; background: var(--surface); }
.myth dt { font-weight: 700; margin-bottom: 6px; }
.myth dd { margin: 0; }
.myth-label { display: inline-block; font: 700 14px/1 var(--sans); padding: 5px 9px; border-radius: 6px; background: var(--bad-soft); color: var(--bad); margin-right: 6px; }
.myth-reality { background: var(--ok-soft); color: var(--ok); }
.video { position: relative; aspect-ratio: 16 / 9; background: #000; border-radius: var(--radius); overflow: hidden; }
.video img, .video iframe { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; border: 0; }
.video-play { display: block; position: absolute; inset: 0; }
.video-button { position: absolute; left: 50%; top: 50%; width: 76px; height: 54px; margin: -27px 0 0 -38px; border-radius: 14px; background: rgba(200, 30, 30, .92); }
.video-button::after { content: ""; position: absolute; left: 31px; top: 15px; border-style: solid; border-width: 12px 0 12px 20px; border-color: transparent transparent transparent #fff; }

/* Quiz */
.quiz { margin: 10px 0; }
.question { border: 1px solid var(--line); border-radius: 12px; padding: 14px 18px 10px; margin: 0 0 14px; background: var(--surface); }
.question legend { font-weight: 700; padding: 0 6px; margin-left: -6px; font-size: 17px; }
.q-num { display: block; font: 700 14px/1.3 var(--sans); color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.q-hint { font-weight: 400; color: var(--muted); font-size: 15px; }
.option { display: flex; gap: 12px; align-items: flex-start; padding: 10px 12px; border-radius: 10px; cursor: pointer; min-height: 44px; }
.option:hover { background: var(--surface-2); }
.option input { width: 20px; height: 20px; margin-top: 4px; flex: none; accent-color: var(--accent); }
.option.is-correct { background: var(--ok-soft); }
.option.is-wrong { background: var(--bad-soft); }
.q-feedback { border-top: 1px dashed var(--line); margin-top: 8px; padding-top: 8px; font-size: 16px; }
.q-feedback .verdict { font-weight: 700; }
.q-feedback.is-right .verdict { color: var(--ok); } .q-feedback.is-wrong .verdict { color: var(--bad); }
.quiz-result { font-weight: 700; font-size: 1.1rem; }
.quiz-result .pass { color: var(--ok); } .quiz-result .fail { color: var(--bad); }
.quiz-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.completion { list-style: none; padding: 0; }
.completion label { display: flex; gap: 12px; align-items: flex-start; padding: 10px 0; cursor: pointer; min-height: 44px; }
.completion input { width: 22px; height: 22px; margin-top: 3px; flex: none; accent-color: var(--ok); }
.completion-status { font-weight: 700; color: var(--ok); }

/* Lesson navigation */
.lesson-nav { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; padding: 28px 0 56px; }
.lesson-nav a { display: block; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 20px; text-decoration: none; color: var(--ink); font-weight: 700; }
.lesson-nav a span { display: block; font: 700 14px/1.3 var(--sans); color: var(--muted); text-transform: uppercase; letter-spacing: .06em; margin-bottom: 4px; }
.lesson-nav a:hover { border-color: var(--accent); }
.lesson-nav-next { text-align: right; }
.resource-list { list-style: none; padding: 0; }
.resource-list li { padding: 12px 0; border-bottom: 1px solid var(--line); }
.resource-list p { margin: 4px 0 0; }

@media (max-width: 900px) {
  .lesson-layout { grid-template-columns: minmax(0, 1fr); gap: 8px; }
  .toc { position: static; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 2px 16px; }
  .toc-mobile { display: block; }
  .toc-desktop { display: none; }
  .toc-course { margin: 0 0 10px; }
}
@media (max-width: 600px) {
  .lesson-nav { grid-template-columns: minmax(0, 1fr); }
  .lesson-nav-next { text-align: left; }
}

/* Newsletter and forms */
.newsletter { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.newsletter h2 { margin-top: 0; }
label { display: block; font-weight: 700; margin: 12px 0 6px; }
input[type="email"], input[type="text"], input[type="file"], select, textarea { width: 100%; font: 16px/1.5 var(--sans); color: var(--ink); background: var(--paper); border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px; }
.field-row { display: flex; gap: 10px; flex-wrap: wrap; } .field-row input { flex: 1 1 220px; }
.form-note { font-size: 15px; color: var(--muted); }
.notice { padding: 12px 16px; border-radius: 10px; background: var(--surface-2); border: 1px solid var(--line); }
.notice-ok { background: var(--ok-soft); color: var(--ok); } .notice-error { background: var(--bad-soft); color: var(--bad); }

/* Footer */
.site-footer { border-top: 1px solid var(--line); background: var(--surface-2); padding: 32px 0 28px; font-size: 16px; color: var(--ink-soft); }
.footer-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 24px; }
.footer-brand { display: flex; align-items: center; gap: 10px; font: 700 1.15rem var(--serif); color: var(--ink); margin-bottom: 6px; }
.footer-links { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 6px 18px; align-content: start; }
.footer-links a { display: inline-block; padding: 6px 0; }
.footer-note { grid-column: 1 / -1; font-size: 15px; color: var(--muted); margin: 0; }
@media (max-width: 700px) { .footer-grid { grid-template-columns: 1fr; } }

/* Owner workspace */
.admin { padding: 24px 0 56px; }
.admin-card { margin: 18px 0; }
.admin-card-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline; gap: 10px; }
.admin-card-head h2 { margin: 0; }
.admin-table { font-size: 15px; }
.admin-table tr.is-live td { background: var(--ok-soft); }
.admin-table tr.is-planned td { color: var(--muted); }
.row-actions { white-space: nowrap; }
.admin-actions { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.admin-form { max-width: 980px; }
.code-input { font: 14px/1.5 var(--mono); min-height: 280px; }
.admin-message:not(:empty) { margin: 14px 0; padding: 14px 18px; border-radius: 10px; border: 1px solid var(--line); background: var(--surface); max-width: 980px; }
.admin-message .ok { color: var(--ok); font-weight: 700; } .admin-message .bad { color: var(--bad); font-weight: 700; }
.admin-message ul { margin: 8px 0 0; padding-left: 1.2em; font: 14px/1.5 var(--mono); }
.materials details { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 10px 18px; margin: 10px 0; }
.materials summary { cursor: pointer; font-weight: 700; }
.crumbs-simple { font-size: 15px; }
.inline-label { display: inline-flex; gap: 8px; align-items: center; font-weight: 600; margin: 0; }
.inline-label select { width: auto; padding: 6px 10px; }
.reorder li { padding: 6px 0; }
.preview-banner { background: var(--advanced); color: #fff; padding: 10px 0; font-size: 15px; }
.preview-banner a { color: #fff; }
.preview-materials { border-top: 4px solid var(--advanced); margin-top: 24px; }

/* Mobile reading sizes (Atlas Web Excellence Standard) */
@media (max-width: 600px) {
  body { font-size: 17px; line-height: 1.7; }
  .prose, .prose p, .prose li, .lead { font-size: 18px; line-height: 1.8; }
  .lead { font-size: 18px; }
  .prose h4 { font-size: 20px; }
  .prose h5 { font-size: 19px; }
  .prose h6 { font-size: 18px; }
  h1 { font-size: 2rem; }
  .hero { padding: 28px 0 24px; }
  .section { padding: 36px 0; }
  .hero-card, .panel, .course-card, .newsletter, .path-card { padding: 20px; }
  .demo { padding: 4px 16px 14px; }
  .advanced { padding: 6px 16px 16px; }
  .logo { font-size: 1.1rem; }
}
@media (prefers-reduced-motion: reduce) { * { transition: none !important; scroll-behavior: auto !important; } }
@media print { .site-header, .site-footer, .toc, .lesson-nav, .copy-button, .quiz-actions { display: none; } body { background: #fff; color: #000; } }