/* Digital Practice - "architectural sheet" design system.
   Paper, ink and hairlines; a serif display face; mono labels; one blue accent and a red-pencil signal.
   Logical properties only (inline/block, start/end) so RTL mirrors automatically. */

:root {
  --paper: #f3f0e8;
  --paper-2: #ebe7dc;
  --surface: #faf8f3;
  --ink: #141414;
  --ink-2: #3a3935;
  --muted: #6d6a62;
  --rule: #d4cfc2;
  --rule-strong: #141414;
  --accent: #1f3f9e;
  --accent-soft: #e2e6f3;
  --signal: #e0492f;
  --success: #2c7a4b;
  --success-soft: #e0efe5;
  --blueprint: #1d4e89;
  --on-ink: #f3f0e8;
  --focus: #e0492f;

  --serif: "Frank Ruhl Libre", "Times New Roman", Georgia, serif;
  --sans: "IBM Plex Sans", "IBM Plex Sans Hebrew", system-ui, -apple-system, "Segoe UI", Arial, sans-serif;
  --mono: "IBM Plex Mono", "IBM Plex Sans Hebrew", ui-monospace, Consolas, monospace;

  --header-h: 68px;
  --gutter: 16px;
  --radius: 2px;
  color-scheme: light;
}

/* Hebrew: Heebo for display type (the serif reads poorly in Hebrew headings). */
:root:lang(he) {
  --serif: "Heebo", "IBM Plex Sans Hebrew", system-ui, sans-serif;
}
:lang(he) h1, :lang(he) h2, :lang(he) h3 { font-weight: 600; letter-spacing: -0.01em; }
:lang(he) h1 { font-weight: 700; line-height: 1.08; }
:lang(he) .index-title, :lang(he) .module-title, :lang(he) .showcase-caption strong,
:lang(he) .project-card strong, :lang(he) .brief-body h3 { font-weight: 600; }

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #121210;
    --paper-2: #1b1a17;
    --surface: #171714;
    --ink: #ece8dd;
    --ink-2: #cfcabd;
    --muted: #9b978c;
    --rule: #34322d;
    --rule-strong: #ece8dd;
    --accent: #9db1ff;
    --accent-soft: #1d2340;
    --signal: #ff7a5c;
    --success: #6fcf97;
    --success-soft: #16301f;
    --on-ink: #121210;
    --focus: #ff7a5c;
    color-scheme: dark;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; min-block-size: 100vh; display: flex; flex-direction: column;
  font-family: var(--sans); font-size: 1rem; line-height: 1.6; color: var(--ink); background: var(--paper);
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
}
main { flex: 1; outline: none; }
h1, h2, h3, h4 { margin-block: 0 0.5em; line-height: 1.12; font-weight: 500; }
h1, h2, h3 { font-family: var(--serif); letter-spacing: -0.015em; }
h1 { font-size: clamp(2.4rem, 1.4rem + 4vw, 4.6rem); font-weight: 500; letter-spacing: -0.025em; }
h2 { font-size: clamp(1.6rem, 1.2rem + 1.4vw, 2.3rem); }
h3 { font-size: 1.3rem; }
.h4, h4 { font-family: var(--mono); font-size: 0.75rem; font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); }
p { margin-block: 0 1em; }
a { color: inherit; text-decoration-color: var(--rule); text-decoration-thickness: 1px; text-underline-offset: 4px; }
a:hover { text-decoration-color: var(--signal); }
img { max-inline-size: 100%; display: block; }
h1:focus { outline: none; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 3px; }
::selection { background: var(--signal); color: #fff; }

.container { inline-size: min(1280px, 100%); margin-inline: auto; padding-inline: var(--gutter); }
@media (min-width: 720px) { :root { --gutter: 32px; } }
@media (min-width: 1200px) { :root { --gutter: 48px; } }
.section { padding-block: 56px 16px; }
.muted { color: var(--muted); }
.small { font-size: 0.875rem; }
.lead { font-size: clamp(1.05rem, 0.95rem + 0.4vw, 1.25rem); color: var(--ink-2); max-inline-size: 58ch; }
.prose { font-size: 1.1rem; max-inline-size: 68ch; color: var(--ink-2); }
.eyebrow, .kicker { font-family: var(--mono); font-size: 0.72rem; font-weight: 500; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); margin: 0; }
.kicker { color: var(--signal); margin-block-end: 20px; display: flex; align-items: center; gap: 10px; }
.kicker::before { content: ""; inline-size: 28px; block-size: 1px; background: currentColor; }
.visually-hidden { position: absolute; inline-size: 1px; block-size: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }

.icon { inline-size: 1.1em; block-size: 1.1em; flex: none; vertical-align: -0.18em; }
[dir="rtl"] .flip-rtl { transform: scaleX(-1); }

.skip-link { position: absolute; inset-inline-start: 16px; inset-block-start: -100px; z-index: 100; background: var(--ink); color: var(--on-ink); padding: 8px 16px; }
.skip-link:focus { inset-block-start: 12px; }

/* ---------- Header ---------- */
.site-header { position: sticky; inset-block-start: 0; z-index: 20; background: color-mix(in srgb, var(--paper) 90%, transparent); backdrop-filter: blur(10px); border-block-end: 1px solid var(--rule); }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; block-size: var(--header-h); }
.brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; color: var(--ink); }
.brand-mark { inline-size: 28px; block-size: 28px; color: var(--ink); }
.brand-name { font-family: var(--serif); font-size: 1.35rem; font-weight: 500; letter-spacing: -0.01em; }
.header-nav { display: flex; align-items: center; gap: 28px; }
.header-nav > a { font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.08em; text-transform: uppercase; text-decoration: none; }
.header-nav > a:hover { color: var(--signal); }
@media (max-width: 560px) { .header-nav > a { display: none; } .brand-name { font-size: 1.15rem; } }
.lang-switch { display: flex; align-items: center; font-family: var(--mono); font-size: 0.78rem; }
.lang-switch button { font: inherit; border: 0; background: none; color: var(--muted); cursor: pointer; padding: 6px 8px; min-block-size: 36px; letter-spacing: 0.04em; }
.lang-switch button + button { border-inline-start: 1px solid var(--rule); }
.lang-switch button[aria-pressed="true"] { color: var(--ink); text-decoration: underline; text-decoration-color: var(--signal); text-underline-offset: 6px; }

/* ---------- Buttons, tags, progress ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 12px;
  font-family: var(--mono); font-size: 0.8rem; font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase;
  text-decoration: none; cursor: pointer; min-block-size: 48px; padding: 10px 22px;
  border: 1px solid var(--ink); border-radius: var(--radius); background: transparent; color: var(--ink);
  transition: background-color 0.15s, color 0.15s, border-color 0.15s;
}
.btn .icon { transition: transform 0.2s; }
.btn:hover .icon.flip-rtl { transform: translateX(3px); }
[dir="rtl"] .btn:hover .icon.flip-rtl { transform: scaleX(-1) translateX(3px); }
.btn-primary { background: var(--ink); color: var(--on-ink); }
.btn-primary:hover { background: var(--signal); border-color: var(--signal); color: #fff; }
.btn-ghost:hover { background: var(--ink); color: var(--on-ink); }
.btn-sm { min-block-size: 38px; padding: 6px 14px; font-size: 0.72rem; }
.btn-done { background: var(--success-soft); color: var(--success); border-color: var(--success); }
.btn-light { background: var(--paper); color: var(--ink); }
.btn-icon { border: 0; background: none; color: var(--muted); cursor: pointer; padding: 8px; font-size: 1.1rem; }
.tag {
  display: inline-flex; align-items: center; gap: 4px; white-space: nowrap; vertical-align: middle;
  font-family: var(--mono); font-size: 0.66rem; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 1px 7px; border: 1px solid currentColor; border-radius: var(--radius); color: var(--accent); margin-inline-start: 8px;
}
.tag-muted { color: var(--muted); }
.tag-type { margin-inline-start: 0; color: var(--ink); }
.progress { block-size: 3px; background: var(--rule); overflow: hidden; margin-block: 8px 4px; }
.progress span { display: block; block-size: 100%; background: var(--signal); }

/* ---------- Spec tables (title-block style) ---------- */
.spec { margin: 0; display: grid; border-block-start: 1px solid var(--rule-strong); }
.spec > div { padding: 10px 14px 10px 0; border-block-end: 1px solid var(--rule); }
.spec dt { font-family: var(--mono); font-size: 0.66rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
.spec dd { margin: 2px 0 0; font-family: var(--serif); font-size: 1.35rem; line-height: 1.2; }
.spec-row { grid-template-columns: repeat(4, 1fr); margin-block-start: 40px; }
.spec-row > div + div { padding-inline-start: 14px; border-inline-start: 1px solid var(--rule); }
@media (max-width: 520px) { .spec-row { grid-template-columns: repeat(2, 1fr); } .spec-row > div:nth-child(3) { border-inline-start: 0; padding-inline-start: 0; } }
.spec-grid { grid-template-columns: repeat(3, 1fr); border: 0; border-block-start: 1px solid var(--rule-strong); }
.spec-grid > div { padding: 10px 12px; border-inline-end: 1px solid var(--rule); }
.spec-grid > div:nth-child(3n) { border-inline-end: 0; }
.spec-grid dd { font-size: 1.05rem; }
@media (max-width: 520px) { .spec-grid { grid-template-columns: repeat(2, 1fr); } .spec-grid > div:nth-child(3n) { border-inline-end: 1px solid var(--rule); } .spec-grid > div:nth-child(2n) { border-inline-end: 0; } }

/* ---------- Sheet (framed drawing with a title block) ---------- */
.sheet { margin: 0; background: var(--surface); border: 1px solid var(--rule-strong); position: relative; }
.sheet::before, .sheet::after { /* registration marks */
  content: ""; position: absolute; inline-size: 14px; block-size: 14px; border: 0 solid var(--signal); pointer-events: none;
}
.sheet::before { inset-block-start: -8px; inset-inline-start: -8px; border-block-start-width: 1px; border-inline-start-width: 1px; }
.sheet::after { inset-block-end: -8px; inset-inline-end: -8px; border-block-end-width: 1px; border-inline-end-width: 1px; }
.sheet-drawing { overflow: hidden; }
.sheet-drawing img { inline-size: 100%; block-size: auto; }
.title-block { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; border-block-start: 1px solid var(--rule-strong); font-family: var(--mono); font-size: 0.8rem; }
.title-block span { padding: 8px 12px; display: grid; gap: 2px; }
.title-block span + span { border-inline-start: 1px solid var(--rule); }
.title-block b { font-weight: 500; font-size: 0.62rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }

/* ---------- Home ---------- */
.hero { border-block-end: 1px solid var(--rule); position: relative; }
.hero::before { /* drafting grid */
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0.55;
  background-image: linear-gradient(var(--rule) 1px, transparent 1px), linear-gradient(90deg, var(--rule) 1px, transparent 1px);
  background-size: 48px 48px; mask-image: linear-gradient(to bottom, #000, transparent 85%);
}
.hero-grid { position: relative; display: grid; gap: 48px; align-items: center; padding-block: 56px; }
@media (min-width: 980px) { .hero-grid { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); padding-block: 88px 80px; gap: 64px; } }
.hero-text h1 { margin-block-end: 24px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 16px 24px; margin-block-start: 32px; }
.sheet .sheet-drawing { background: var(--blueprint); background-image: linear-gradient(135deg, #1d4e89, #1f6f8b 60%, #2a9d8f); padding: 12px; }
.sheet-cover .sheet-drawing { background: var(--surface); padding: 0; }
.sheet-cover .sheet-drawing img { aspect-ratio: 3 / 2; object-fit: cover; }

.section-title { display: flex; align-items: baseline; gap: 16px; padding-block-start: 14px; border-block-start: 1px solid var(--rule-strong); margin-block-end: 28px; }
.section-num { font-family: var(--mono); font-size: 0.78rem; font-weight: 500; color: var(--signal); letter-spacing: 0.06em; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 16px; }
.section-head .section-title { flex: 1; }
.section-head .btn { margin-block-end: 28px; }

.how-steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr)); }
.how-step { padding: 8px 32px 8px 0; }
@media (min-width: 820px) { .how-step + .how-step { padding-inline-start: 32px; border-inline-start: 1px solid var(--rule); } }
.how-num { font-family: var(--serif); font-size: 3.4rem; line-height: 1; color: var(--rule); display: block; margin-block-end: 12px; }
.how-step h3 { font-size: 1.35rem; }
.how-step p { color: var(--ink-2); margin: 0; max-inline-size: 36ch; }

/* Course index */
.course-index { list-style: none; margin: 0; padding: 0; border-block-start: 1px solid var(--rule); }
.index-row { border-block-end: 1px solid var(--rule); }
.index-link, .index-soon { display: grid; grid-template-columns: 48px minmax(0, 1fr); gap: 16px 28px; align-items: center; padding: 24px 0; text-decoration: none; color: inherit; }
@media (min-width: 900px) {
  .index-link { grid-template-columns: 56px 300px minmax(0, 1fr) 200px 32px; }
  .index-soon { grid-template-columns: 56px minmax(0, 1fr); }
}
.index-num { font-family: var(--mono); font-size: 0.8rem; color: var(--muted); align-self: start; padding-block-start: 6px; }
.index-thumb { grid-column: 1 / -1; border: 1px solid var(--rule); background: var(--surface); overflow: hidden; }
@media (min-width: 900px) { .index-thumb { grid-column: auto; } }
.index-thumb img { inline-size: 100%; block-size: auto; aspect-ratio: 3 / 2; object-fit: cover; transition: transform 0.5s ease; }
.index-main { display: grid; gap: 6px; grid-column: 1 / -1; }
@media (min-width: 900px) { .index-main { grid-column: auto; } }
.index-soon .index-main { grid-column: auto; }
.index-title { font-family: var(--serif); font-size: clamp(1.5rem, 1.2rem + 1vw, 2.1rem); line-height: 1.12; letter-spacing: -0.015em; }
.index-sub { color: var(--ink-2); max-inline-size: 52ch; }
.index-progress { display: flex; align-items: center; gap: 10px; font-family: var(--mono); font-size: 0.72rem; color: var(--muted); }
.index-progress .progress { inline-size: 140px; margin: 0; }
.index-meta { display: grid; gap: 4px; font-family: var(--mono); font-size: 0.75rem; color: var(--muted); grid-column: 1 / -1; }
@media (min-width: 900px) { .index-meta { grid-column: auto; padding-inline-start: 20px; border-inline-start: 1px solid var(--rule); } }
.index-arrow { display: none; }
@media (min-width: 900px) { .index-arrow { display: block; font-size: 1.3rem; transition: transform 0.2s; } }
.index-link:hover .index-title { text-decoration: underline; text-decoration-color: var(--signal); text-decoration-thickness: 1px; text-underline-offset: 6px; }
.index-link:hover .index-thumb img { transform: scale(1.04); }
.index-link:hover .index-arrow { transform: translateX(6px); color: var(--signal); }
[dir="rtl"] .index-link:hover .index-arrow { transform: translateX(-6px); }
.index-soon .index-title { color: var(--muted); }

/* Showcase */
.showcase { list-style: none; margin: 0; padding: 0; display: grid; gap: 32px 24px; grid-template-columns: repeat(auto-fill, minmax(min(100%, 340px), 1fr)); }
.showcase a { display: grid; gap: 12px; text-decoration: none; color: inherit; }
.showcase-frame { border: 1px solid var(--rule); background: var(--surface); overflow: hidden; }
.showcase img { inline-size: 100%; block-size: auto; aspect-ratio: 16 / 10; object-fit: cover; transition: transform 0.5s ease; }
.showcase a:hover img { transform: scale(1.03); }
.showcase a:hover .showcase-frame { border-color: var(--ink); }
.showcase-caption { display: grid; gap: 4px; }
.showcase-caption strong { font-family: var(--serif); font-weight: 500; font-size: 1.3rem; line-height: 1.2; }

/* ---------- Course page ---------- */
.course-hero { border-block-end: 1px solid var(--rule); }
.course-hero-inner { display: grid; gap: 40px; padding-block: 40px 56px; align-items: end; }
@media (min-width: 980px) { .course-hero-inner { grid-template-columns: minmax(0, 1fr) minmax(0, 0.95fr); gap: 64px; padding-block: 56px 72px; } }
.breadcrumb { display: flex; flex-wrap: wrap; gap: 10px; font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); margin-block-end: 28px; }
.breadcrumb a { text-decoration: none; }
.breadcrumb a:hover { color: var(--signal); }
.hero-progress { display: flex; align-items: center; gap: 12px; font-family: var(--mono); font-size: 0.75rem; color: var(--muted); }
.hero-progress .progress { inline-size: 160px; margin: 0; }

.course-layout { display: grid; gap: 8px 64px; padding-block-end: 64px; }
@media (min-width: 1000px) { .course-layout { grid-template-columns: minmax(0, 1fr) 320px; } }
.course-aside { padding-block: 56px 0; display: grid; gap: 24px; align-content: start; }
@media (min-width: 1000px) { .course-aside { position: sticky; inset-block-start: calc(var(--header-h) + 24px); align-self: start; } }
.panel { border-block-start: 1px solid var(--rule-strong); padding-block: 14px; }
.panel .h4 { margin-block-end: 8px; }
.instructor { font-family: var(--serif); font-size: 1.3rem; margin-block-end: 4px; }
.project-card { display: grid; text-decoration: none; color: inherit; border: 1px solid var(--rule-strong); background: var(--surface); }
.project-card img { inline-size: 100%; block-size: auto; aspect-ratio: 3 / 2; object-fit: cover; border-block-end: 1px solid var(--rule); }
.project-card-body { display: grid; gap: 4px; padding: 16px 18px 18px; }
.project-card strong { font-family: var(--serif); font-weight: 500; font-size: 1.45rem; line-height: 1.15; }
.project-card-cta { display: inline-flex; align-items: center; gap: 8px; margin-block-start: 10px; font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; }
.project-card:hover { border-color: var(--signal); }
.project-card:hover .project-card-cta { color: var(--signal); }

.check-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 0 40px; }
@media (min-width: 720px) { .check-list { grid-template-columns: 1fr 1fr; } }
.check-list li { display: flex; gap: 14px; align-items: flex-start; padding-block: 12px; border-block-end: 1px solid var(--rule); }
.check-list .icon { color: var(--signal); margin-block-start: 0.25em; }
.check-list.single { grid-template-columns: 1fr; font-size: 0.95rem; }

/* Syllabus */
.module-list { border-block-start: 1px solid var(--rule); }
.module { border-block-end: 1px solid var(--rule); }
.module > summary, .outline-module > summary { list-style: none; cursor: pointer; }
.module > summary::-webkit-details-marker, .outline-module > summary::-webkit-details-marker { display: none; }
.module > summary { display: grid; grid-template-columns: 52px minmax(0, 1fr) auto 24px; gap: 16px; align-items: center; padding-block: 20px; }
.module-code { font-family: var(--serif); font-size: 1.8rem; line-height: 1; color: var(--muted); }
.module-head { display: grid; gap: 2px; }
.module-title { font-family: var(--serif); font-size: 1.4rem; line-height: 1.2; }
.module > summary:hover .module-title { text-decoration: underline; text-decoration-color: var(--signal); text-decoration-thickness: 1px; text-underline-offset: 5px; }
.module-stats { font-family: var(--mono); font-size: 0.72rem; color: var(--muted); text-align: end; line-height: 1.5; }
.chevron { color: var(--muted); transition: transform 0.2s; }
details[open] > summary .chevron { transform: rotate(180deg); }
.module[open] .module-code { color: var(--signal); }
.module-body { padding: 0 0 28px; display: grid; gap: 28px; }
@media (min-width: 760px) {
  .module-body { padding-inline-start: 68px; }
  .module-body.has-figure { grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr); align-items: start; }
}
.module-summary { color: var(--ink-2); max-inline-size: 60ch; }
.module-figure { margin: 0; border: 1px solid var(--rule); background: var(--surface); }
.module-figure img { inline-size: 100%; block-size: auto; }
@media (min-width: 760px) { .module-figure { position: sticky; inset-block-start: calc(var(--header-h) + 16px); } }
.materials-heading { margin-block: 24px 10px; }

.step-list { list-style: none; padding: 0; margin: 0; border-block-start: 1px solid var(--rule); }
.step-list li + li { border-block-start: 1px solid var(--rule); }
.step-row, .outline-step { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 12px; padding: 10px 4px; text-decoration: none; color: var(--ink); }
.step-row:hover, .outline-step:hover { background: var(--paper-2); }
.step-icon { display: grid; place-items: center; inline-size: 26px; block-size: 26px; color: var(--muted); }
.is-done .step-icon { color: var(--success); }
.step-title { font-size: 0.97rem; }
.step-meta { font-family: var(--mono); font-size: 0.75rem; color: var(--muted); font-variant-numeric: tabular-nums; }

.file-list { list-style: none; padding: 0; margin: 0; border-block-start: 1px solid var(--rule); }
.file-row { display: grid; grid-template-columns: 52px minmax(0, 1fr) auto; align-items: center; gap: 12px; padding: 10px 0; border-block-end: 1px solid var(--rule); }
.file-type { font-family: var(--mono); font-size: 0.68rem; font-weight: 500; letter-spacing: 0.06em; text-align: center; padding: 3px 0; border: 1px solid var(--ink); }
.file-name { display: grid; line-height: 1.35; overflow-wrap: anywhere; }
.file-name small { font-family: var(--mono); font-size: 0.72rem; color: var(--muted); }
.file-row .tag { margin: 0; }

/* ---------- Learn view ---------- */
.learn { display: grid; min-block-size: calc(100vh - var(--header-h)); }
@media (min-width: 1024px) { .learn { grid-template-columns: 360px 1fr; } }
.outline { background: var(--paper); border-inline-end: 1px solid var(--rule); overflow-y: auto; overscroll-behavior: contain; padding: 20px 16px 40px; }
@media (min-width: 1024px) {
  .outline { position: sticky; inset-block-start: var(--header-h); block-size: calc(100vh - var(--header-h)); }
  .outline-close, .outline-open, .outline-backdrop { display: none !important; }
}
.outline-head { position: relative; padding: 0 4px 16px; border-block-end: 1px solid var(--rule-strong); margin-block-end: 8px; }
.outline-course { display: block; font-family: var(--serif); font-size: 1.25rem; line-height: 1.2; text-decoration: none; padding-inline-end: 36px; }
.outline-close { position: absolute; inset-inline-end: 0; inset-block-start: -4px; }
.outline nav { display: grid; }
.outline-module { border-block-end: 1px solid var(--rule); }
.outline-module > summary { display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 12px 4px; }
.outline-module .module-title { font-size: 1.05rem; }
.outline-module .step-list { border: 0; padding-block-end: 8px; }
.outline-module .step-list li + li { border: 0; }
.outline-step { padding: 7px 8px; font-size: 0.9rem; border-inline-start: 2px solid transparent; }
.outline-step .step-icon { inline-size: 22px; block-size: 22px; }
.outline-step.is-current { background: var(--paper-2); border-inline-start-color: var(--signal); font-weight: 500; }
.outline-step.is-current .step-icon { color: var(--signal); }

:root { --dir: 1; }
[dir="rtl"] { --dir: -1; }
@media (max-width: 1023px) {
  .outline {
    position: fixed; z-index: 40; inset-block: 0; inset-inline-start: 0; inline-size: min(380px, 90vw);
    transform: translateX(calc(var(--dir) * -105%)); visibility: hidden;
    transition: transform 0.25s ease, visibility 0s linear 0.25s;
  }
  .outline-is-open .outline { transform: none; visibility: visible; transition: transform 0.25s ease; }
  .outline-backdrop { position: fixed; inset: 0; z-index: 30; background: rgb(0 0 0 / 40%); opacity: 0; pointer-events: none; transition: opacity 0.25s; }
  .outline-is-open .outline-backdrop { opacity: 1; pointer-events: auto; }
}

.viewer { padding: 20px var(--gutter) 64px; inline-size: min(1040px, 100%); margin-inline: auto; }
.viewer-bar { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-block-end: 20px; min-block-size: 38px; font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.06em; text-transform: uppercase; }
.viewer-bar a { text-decoration: none; }
@media (min-width: 1024px) { .viewer-bar { justify-content: flex-end; } }
.player { position: relative; aspect-ratio: 16 / 9; background: #0d0d0c; border: 1px solid var(--rule-strong); overflow: hidden; }
.player iframe, .player-poster { position: absolute; inset: 0; inline-size: 100%; block-size: 100%; border: 0; }
.player-poster { padding: 0; cursor: pointer; background: #0d0d0c; }
.player-poster img { inline-size: 100%; block-size: 100%; object-fit: cover; opacity: 0.8; transition: opacity 0.2s; }
.player-poster:hover img { opacity: 1; }
.play-button { position: absolute; inset: 0; margin: auto; inline-size: 84px; block-size: 84px; display: grid; place-items: center; background: var(--paper); color: var(--ink); font-size: 1.8rem; border: 1px solid var(--ink); transition: background-color 0.15s, color 0.15s; }
.player-poster:hover .play-button, .player-poster:focus-visible .play-button { background: var(--signal); color: #fff; border-color: var(--signal); }
.play-button .icon { margin-inline-start: 4px; }

.stage-card { display: grid; justify-items: center; text-align: center; gap: 10px; padding: 48px 28px; background: var(--surface); border: 1px solid var(--rule-strong); }
.stage-card p { max-inline-size: 62ch; }
.stage-icon { display: grid; place-items: center; inline-size: 52px; block-size: 52px; border: 1px solid var(--ink); font-size: 1.4rem; margin-block-end: 6px; }
.stage-exercise { text-align: start; justify-items: start; gap: 14px; }

.item-head { margin-block: 28px 18px; }
.item-head h1 { font-size: clamp(1.8rem, 1.3rem + 1.6vw, 2.8rem); margin-block: 6px 12px; }
.item-tags { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin: 0; font-family: var(--mono); font-size: 0.75rem; }
.item-tags .tag { margin: 0; }
.item-actions { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; padding-block: 18px; border-block: 1px solid var(--rule); }
@media (max-width: 639px) {
  .item-actions { display: grid; grid-template-columns: 1fr 1fr; }
  .item-actions [data-toggle-done] { grid-column: 1 / -1; order: -1; }
  .item-actions .finished { grid-column: 2; }
}
.finished { margin: 0; font-family: var(--serif); font-size: 1.1rem; color: var(--success); }
.materials { margin-block-start: 32px; }
.materials .h4 { margin-block-end: 10px; }
.code { inline-size: 100%; max-block-size: 320px; overflow: auto; margin: 0; padding: 16px 18px; text-align: start; font: 0.85rem/1.55 var(--mono); background: var(--paper); border: 1px solid var(--rule); white-space: pre; }

/* ---------- Project brief ---------- */
.page-hero { border-block-end: 1px solid var(--rule); }
.page-hero-grid { display: grid; gap: 32px; align-items: end; padding-block: 40px 56px; }
@media (min-width: 900px) { .page-hero-grid { grid-template-columns: minmax(0, 1fr) 440px; gap: 56px; } }
.page-hero .lead { margin: 0; }
.page-hero-image { inline-size: 100%; block-size: auto; border: 1px solid var(--rule-strong); background: var(--surface); }
.brief-layout { display: grid; gap: 48px; padding-block: 48px 72px; align-items: start; }
@media (min-width: 980px) { .brief-layout { grid-template-columns: 360px 1fr; } .brief-site { position: sticky; inset-block-start: calc(var(--header-h) + 24px); } }
.brief-site h2 { font-size: 1.6rem; }
.brief-site .h4 { margin-block: 20px 8px; }
.plot { inline-size: 100%; block-size: auto; margin-block: 8px 16px; font-family: var(--mono); font-size: 12px; fill: var(--muted); }
.plot-land { fill: var(--surface); stroke: var(--ink); stroke-width: 1.5; }
.plot-build { fill: var(--accent-soft); stroke: var(--signal); stroke-width: 1.2; stroke-dasharray: 6 4; }
.plot-area { fill: var(--ink); font-family: var(--serif); font-size: 17px; }
.plot-small { font-size: 11px; }
[dir="rtl"] .plot text { direction: ltr; }
.bullets { margin: 0; padding-inline-start: 1.1em; display: grid; gap: 6px; font-size: 0.95rem; color: var(--ink-2); }
.brief-stages { list-style: none; margin: 0; padding: 0; border-block-start: 1px solid var(--rule-strong); }
.brief-stage { display: grid; grid-template-columns: 64px 1fr; gap: 18px; padding-block: 28px; border-block-end: 1px solid var(--rule); scroll-margin-block-start: calc(var(--header-h) + 16px); }
.brief-stage.is-target { background: linear-gradient(90deg, var(--paper-2), transparent); }
.brief-num { font-family: var(--serif); font-size: 2.4rem; line-height: 1; color: var(--signal); }
.brief-body h3 { font-size: 1.5rem; margin-block: 4px; }
.brief-body > p.small { margin-block-end: 12px; font-family: var(--mono); font-size: 0.75rem; }

.req-list { list-style: none; margin: 0; padding: 0; display: grid; inline-size: 100%; }
.req { display: flex; gap: 12px; align-items: flex-start; padding: 8px 4px; cursor: pointer; border-block-end: 1px dashed var(--rule); }
.req:hover { background: var(--paper-2); }
.req input { appearance: none; inline-size: 16px; block-size: 16px; margin-block-start: 0.3em; flex: none; border: 1px solid var(--ink); border-radius: 0; display: grid; place-content: center; cursor: pointer; }
.req input:checked { background: var(--ink); }
.req input:checked::after { content: ""; inline-size: 8px; block-size: 4px; border: 0 solid var(--on-ink); border-block-end-width: 2px; border-inline-start-width: 2px; transform: rotate(-45deg) translate(1px, -1px); }
.req input:checked + span { color: var(--muted); text-decoration: line-through; text-decoration-color: var(--signal); }
.note { margin: 14px 0 0; padding: 12px 16px; background: var(--paper-2); color: var(--ink-2); font-size: 0.93rem; border-inline-start: 2px solid var(--signal); }

/* ---------- Sign-in (downloads, currently off) ---------- */
.user-slot { display: flex; align-items: center; gap: 8px; }
.user-slot:empty { display: none; }
.user-chip { font-family: var(--mono); font-size: 0.75rem; color: var(--muted); max-inline-size: 180px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
@media (max-width: 640px) { .user-chip { display: none; } }
.signin-box { display: grid; gap: 10px; margin-block-start: 10px; padding: 14px 16px; border: 1px dashed var(--rule); background: var(--paper-2); }
.signin-box p { margin: 0; font-size: 0.92rem; }
.signin-row { display: flex; flex-wrap: wrap; gap: 8px; }
.signin-row input { flex: 1 1 220px; min-block-size: 40px; padding: 6px 12px; font: inherit; color: var(--ink); background: var(--surface); border: 1px solid var(--ink); border-radius: 0; }
.signin-msg:empty { display: none; }
.signin-msg { color: var(--success); }
.signin-msg.is-error { color: var(--signal); }

/* ---------- Footer ---------- */
.site-footer { border-block-start: 1px solid var(--rule-strong); background: var(--paper); }
.footer-inner { display: grid; gap: 32px; padding-block: 48px 28px; }
@media (min-width: 820px) { .footer-inner { grid-template-columns: 1.6fr 1fr 1fr; } }
.footer-name { font-family: var(--serif); font-size: clamp(2rem, 1.4rem + 2vw, 3rem); line-height: 1; letter-spacing: -0.02em; margin: 0 0 10px; }
.footer-tagline { color: var(--muted); margin: 0; }
.footer-col { display: grid; gap: 8px; align-content: start; }
.footer-col .eyebrow { margin-block-end: 6px; }
.footer-col a { text-decoration: none; color: var(--ink-2); }
.footer-col a:hover { color: var(--signal); }
.footer-legal { grid-column: 1 / -1; margin: 12px 0 0; padding-block-start: 16px; border-block-start: 1px solid var(--rule); font-family: var(--mono); font-size: 0.72rem; color: var(--muted); }
body[data-view="learn"] .site-footer { display: none; }

/* ---------- Legal pages ---------- */
.legal { max-inline-size: 760px; }
.legal h2 { font-size: 1.5rem; margin-block-start: 1.6em; }
.legal li { margin-block-end: 0.5em; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}
.gsi-slot { min-block-size: 44px; }
.signin-or { display: flex; align-items: center; gap: 12px; font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
.signin-or::before, .signin-or::after { content: ""; flex: 1; block-size: 1px; background: var(--rule); }