:root {
  /* Palet Warna Pendidikan: Biru Gelap, Biru Terang, dan Putih */
  --canvas: #f8fafc;
  --surface: #ffffff;
  --surface-subtle: #f1f5f9;
  --blue-subtle: #eff6ff;
  --blue-tint: #dbeafe;
  --ink: #0f172a;
  --ink-soft: #334155;
  --ink-muted: #64748b;
  --navy-deep: #091e3a;
  --blue-primary: #1d4ed8;
  --blue-hover: #1e40af;
  --white: #ffffff;
  --line: #e2e8f0;
  --line-strong: #cbd5e1;
  --focus: #2563eb;
  --amber: #b45309;
  --amber-subtle: #fef3c7;

  /* Tata Letak & Spasi */
  --measure: 72rem;
  --reading: 48rem;
  --radius: 0.6rem;
  --radius-sm: 0.35rem;
  --radius-full: 999px;

  /* Bayangan & Elevasi Bersahaja (Anti-Slop R-12) */
  --shadow-sm: 0 1px 2px 0 rgba(9, 30, 58, 0.04);
  --shadow-card: 0 2px 8px -1px rgba(9, 30, 58, 0.06), 0 1px 3px -1px rgba(9, 30, 58, 0.04);
  --shadow-hover: 0 6px 16px -2px rgba(9, 30, 58, 0.08), 0 2px 6px -1px rgba(9, 30, 58, 0.04);
  --shadow-elevated: 0 8px 24px -4px rgba(9, 30, 58, 0.08);

  color-scheme: light;
  font-family: "Atkinson Hyperlegible", "Atkinson Hyperlegible Next", "Trebuchet MS", system-ui, sans-serif;
  font-synthesis: none;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--canvas);
  color: var(--ink);
  scroll-behavior: smooth;
}

body {
  min-width: 20rem;
  margin: 0;
  background: var(--canvas);
  color: var(--ink);
  line-height: 1.68;
}

img,
svg {
  max-width: 100%;
}

a {
  color: var(--blue-primary);
  text-decoration-thickness: 0.1em;
  text-underline-offset: 0.2em;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--blue-hover);
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button,
input,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

:focus-visible {
  outline: 0.2rem solid var(--focus);
  outline-offset: 0.2rem;
}

.skip-link {
  position: absolute;
  z-index: 50;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--navy-deep);
  color: var(--white);
  font-weight: 700;
  text-decoration: none;
  box-shadow: var(--shadow-elevated);
  transform: translateY(-200%);
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

/* ==========================================================================
   Header & Navigasi
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
}

.site-header__inner,
.site-main,
.site-footer__inner {
  width: min(calc(100% - 2.5rem), var(--measure));
  margin-inline: auto;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 4.6rem;
  gap: 1.5rem;
}

.site-title {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  gap: 0.65rem;
  padding-block: 0.35rem;
  color: var(--navy-deep);
  font-family: "Literata", Georgia, serif;
  font-size: 1.18rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.site-title:hover {
  color: var(--blue-primary);
}

.site-title__badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.85rem;
  height: 1.85rem;
  border-radius: var(--radius-sm);
  background: var(--navy-deep);
  color: var(--white);
  font-family: "Atkinson Hyperlegible Next", sans-serif;
  font-size: 0.78rem;
  font-weight: 800;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 2.5rem;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
  color: var(--ink-soft);
  font-size: 0.98rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.15s ease;
}

.site-nav a:hover {
  color: var(--blue-primary);
  background: var(--blue-subtle);
}

.site-nav a[aria-current="page"] {
  color: var(--blue-primary);
  font-weight: 700;
  background: var(--blue-subtle);
  box-shadow: inset 0 -2px 0 var(--blue-primary);
}

.nav-toggle {
  display: none;
  min-width: 4.4rem;
  min-height: 2.75rem;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--navy-deep);
  font-weight: 700;
  transition: all 0.15s ease;
}

.nav-toggle:hover {
  border-color: var(--blue-primary);
  color: var(--blue-primary);
  background: var(--blue-subtle);
}

/* ==========================================================================
   Tata Letak Utama & Tipografi
   ========================================================================== */
.site-main {
  padding-block: clamp(2rem, 5vw, 4rem);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 0.6rem;
  color: var(--blue-primary);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  line-height: 1.3;
  text-transform: uppercase;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: normal;
  text-transform: none;
}

.badge--blue {
  background: var(--blue-subtle);
  border: 1px solid #bfdbfe;
  color: var(--blue-primary);
}

.badge--amber {
  background: var(--amber-subtle);
  border: 1px solid #fde68a;
  color: var(--amber);
}

/* Page Intro Hero with Profile Illustration */
.page-intro {
  margin-bottom: clamp(2rem, 4vw, 3rem);
}

.page-intro--profile {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
}

.page-intro__text {
  max-width: 44rem;
}

.page-intro__media {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-shrink: 0;
}

.page-intro__img {
  width: auto;
  height: clamp(200px, 25vw, 270px);
  max-width: 220px;
  object-fit: contain;
  filter: drop-shadow(0 12px 20px rgba(9, 30, 58, 0.08));
}

/* Tipografi Kutipan Guru (Teacher Quote) */
.teacher-quote {
  margin: 2.25rem 0;
  padding: 1.5rem 1.75rem;
  border-left: 4px solid var(--blue-primary);
  background: var(--blue-subtle);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.teacher-quote p {
  margin: 0 0 0.5rem;
  font-family: "Literata", Georgia, serif;
  font-size: 1.08rem;
  font-style: italic;
  line-height: 1.65;
  color: var(--navy-deep);
}

.teacher-quote cite {
  display: block;
  font-size: 0.88rem;
  font-style: normal;
  font-weight: 700;
  color: var(--blue-primary);
}

h1,
h2,
h3 {
  margin-top: 0;
  color: var(--navy-deep);
  font-family: "Literata", Georgia, serif;
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.22;
}

h1 {
  max-width: 20ch;
  margin-bottom: 1.1rem;
  font-size: clamp(2.2rem, 4.8vw, 3.8rem);
}

h2 {
  margin-bottom: 0.75rem;
  font-size: clamp(1.55rem, 3vw, 2.25rem);
}

h3 {
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
}

p,
ul,
ol {
  max-width: var(--reading);
}

.lede {
  max-width: 38rem;
  margin: 0;
  color: var(--ink-soft);
  font-size: clamp(1.1rem, 2vw, 1.28rem);
  line-height: 1.6;
}

/* ==========================================================================
   Hero Section & Quick Formula Card
   ========================================================================== */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(18rem, 0.85fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center;
  padding-block: clamp(1rem, 3vw, 2.5rem) clamp(2.5rem, 5vw, 4rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  min-height: 2.9rem;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.35rem;
  border: 1px solid var(--blue-primary);
  border-radius: var(--radius-sm);
  background: var(--blue-primary);
  color: var(--white);
  font-weight: 700;
  font-size: 0.98rem;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease;
}

.button:hover {
  border-color: var(--blue-hover);
  background: var(--blue-hover);
  color: var(--white);
  box-shadow: var(--shadow-card);
}

.button:active {
  transform: translateY(1px);
}

.button--quiet {
  background: var(--surface);
  border-color: var(--line-strong);
  color: var(--navy-deep);
  box-shadow: none;
}

.button--quiet:hover {
  background: var(--blue-subtle);
  border-color: var(--blue-primary);
  color: var(--blue-primary);
}

/* Quick Concept Card (Hero Right Column) */
.concept-card {
  padding: 1.75rem;
  border: 1px solid #bfdbfe;
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
}

.concept-card__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 1.25rem;
}

.concept-card__title {
  margin: 0;
  color: var(--navy-deep);
  font-size: 0.92rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.concept-card__stage {
  padding: 1.25rem;
  border-radius: var(--radius-sm);
  background: var(--blue-subtle);
  border: 1px solid #dbeafe;
  text-align: center;
  margin-bottom: 1.25rem;
}

.concept-card__formula {
  margin: 0 0 0.5rem;
  color: var(--navy-deep);
  font-family: "Literata", Georgia, serif;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 700;
}

.concept-card__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.concept-card__col {
  padding: 0.75rem;
  border-radius: var(--radius-sm);
  background: var(--surface-subtle);
  border: 1px solid var(--line);
}

.concept-card__label {
  display: block;
  font-size: 0.76rem;
  font-weight: 800;
  color: var(--blue-primary);
  text-transform: uppercase;
  margin-bottom: 0.2rem;
}

.concept-card__value {
  margin: 0;
  font-size: 0.92rem;
  color: var(--navy-deep);
  font-weight: 600;
}

.concept-card__footer {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
  line-height: 1.5;
}

/* ==========================================================================
   Section & Learning Path Module Cards
   ========================================================================== */
.section {
  padding-block: clamp(2.5rem, 5vw, 4rem);
  border-top: 1px solid var(--line);
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 1.75rem;
}

.section-heading p {
  margin: 0;
  color: var(--ink-soft);
}

/* Modul Bab Belajar (Module Card) */
.module-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  margin-bottom: 1.5rem;
}

.module-card__header {
  padding: 1.5rem;
  background: linear-gradient(to right, #f8fafc, #ffffff);
  border-bottom: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.module-card__header-main {
  min-width: 0;
}

.module-card__title {
  margin: 0.35rem 0 0.2rem;
  color: var(--navy-deep);
  font-size: 1.4rem;
}

.module-card__desc {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.module-card__items {
  padding: 0;
  margin: 0;
  list-style: none;
}

.module-item {
  display: grid;
  grid-template-columns: 3.5rem minmax(0, 1fr) auto;
  gap: 1.25rem;
  align-items: center;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--line);
  transition: background 0.15s ease;
}

.module-item:last-child {
  border-bottom: none;
}

.module-item:hover {
  background: #fbfdff;
}

.module-item__number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: var(--radius-sm);
  background: var(--blue-subtle);
  border: 1px solid #bfdbfe;
  color: var(--blue-primary);
  font-weight: 800;
  font-size: 1.05rem;
}

.module-item__main h3 {
  margin: 0 0 0.25rem;
  font-size: 1.15rem;
}

.module-item__main h3 a {
  color: var(--navy-deep);
  text-decoration: none;
}

.module-item__main h3 a:hover {
  color: var(--blue-primary);
}

.module-item__meta {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.88rem;
  color: var(--ink-muted);
}

/* Kartu Profil Guru (Teacher's Note) */
.teacher-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 1.75rem;
  align-items: center;
  padding: 2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
}

.teacher-avatar {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 4.5rem;
  height: 4.5rem;
  border-radius: var(--radius-full);
  background: var(--navy-deep);
  color: var(--white);
  font-family: "Literata", Georgia, serif;
  font-size: 1.4rem;
  font-weight: 700;
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
}

.teacher-avatar--img {
  width: 5.5rem;
  height: 5.5rem;
  padding: 0.35rem;
  background: linear-gradient(135deg, var(--blue-pale) 0%, #e2e8f0 100%);
  border: 2px solid var(--blue-soft);
  border-radius: var(--radius-full);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
}

.teacher-avatar--img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.teacher-card__figure {
  width: auto;
  height: 115px;
  max-width: 95px;
  object-fit: contain;
  filter: drop-shadow(0 6px 12px rgba(9, 30, 58, 0.08));
  flex-shrink: 0;
}

.error-illustration {
  width: 7.5rem;
  height: 7.5rem;
  object-fit: contain;
  margin: 0 auto 1.25rem;
  display: block;
  filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.05));
}

.teacher-info h2 {
  margin: 0 0 0.35rem;
  font-size: 1.45rem;
}

.teacher-info p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.98rem;
}

/* ==========================================================================
   Halaman Materi & Navigasi Cepat (Jump Nav & Step Lists)
   ========================================================================== */
.breadcrumb {
  margin: 0 0 1.25rem;
  color: var(--ink-muted);
  font-size: 0.92rem;
}

.breadcrumb a {
  display: inline-flex;
  min-height: 2.75rem;
  min-width: 2.75rem;
  align-items: center;
  color: var(--blue-primary);
  font-weight: 600;
}

.breadcrumb a:hover {
  color: var(--blue-hover);
}

.jump-nav {
  display: none;
  overflow-x: auto;
  white-space: nowrap;
  gap: 0.5rem;
  padding-block: 0.6rem 1rem;
  margin-bottom: 1.5rem;
  -webkit-overflow-scrolling: touch;
}

.jump-nav a {
  display: inline-flex;
  align-items: center;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-full);
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--navy-deep);
  font-size: 0.88rem;
  font-weight: 700;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
}

.jump-nav a:hover,
.jump-nav a:active {
  background: var(--blue-subtle);
  border-color: var(--blue-primary);
  color: var(--blue-primary);
}

.content-layout {
  display: grid;
  grid-template-columns: minmax(13rem, 16rem) minmax(0, var(--reading));
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: start;
}

.toc {
  position: sticky;
  top: 6rem;
  padding: 1.35rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}

.toc h2 {
  margin-bottom: 0.85rem;
  color: var(--navy-deep);
  font-family: inherit;
  font-size: 0.84rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.toc ol {
  margin: 0;
  padding-left: 1.2rem;
}

.toc li + li {
  margin-top: 0.45rem;
}

.toc a {
  display: inline-flex;
  min-height: 2.25rem;
  align-items: center;
  color: var(--ink-soft);
  font-size: 0.94rem;
  font-weight: 600;
  text-decoration: none;
}

.toc a:hover {
  color: var(--blue-primary);
  text-decoration: underline;
}

.toc a.is-active {
  color: var(--blue-primary);
  font-weight: 700;
  border-left: 3px solid var(--blue-primary);
  padding-left: 0.45rem;
  text-decoration: none;
}

.jump-nav a.is-active {
  background: var(--blue-primary);
  color: var(--white);
  border-color: var(--blue-primary);
}

.article {
  min-width: 0;
}

.article h2 {
  margin-top: 2.8rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--line);
}

.article h3 {
  margin-top: 1.8rem;
}

.article p,
.article li {
  font-size: 1.05rem;
  color: var(--ink);
}

.article ul,
.article ol {
  padding-left: 1.5rem;
}

/* Langkah Pengerjaan Soal (Step-by-Step Flow) */
.step-card {
  margin-block: 1.5rem;
  padding: 1.5rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}

.step-card h3 {
  margin-top: 0;
  margin-bottom: 0.75rem;
  color: var(--navy-deep);
}

.step-list {
  margin: 1.15rem 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.step-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.9rem;
  align-items: baseline;
}

.step-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-sm);
  background: var(--blue-subtle);
  border: 1px solid #bfdbfe;
  color: var(--blue-primary);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.step-text {
  margin: 0;
  font-size: 1rem;
  color: var(--ink);
}

/* Kotak Notasi Rumus Matematika (KaTeX) */
.formula {
  max-width: 100%;
  overflow-x: auto;
  margin-block: 1.5rem;
  padding: 1.35rem;
  border: 1px solid #bfdbfe;
  border-left: 0.4rem solid var(--blue-primary);
  border-radius: var(--radius);
  background: var(--blue-subtle);
  color: var(--navy-deep);
  font-size: 1.18rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding-block: 0.25rem;
}

/* Callout Catatan Penting */
.callout {
  margin-block: 1.6rem;
  padding: 1.35rem;
  border: 1px solid #fde68a;
  border-left: 0.4rem solid var(--amber);
  border-radius: var(--radius);
  background: #fffbeb;
  box-shadow: var(--shadow-sm);
}

.callout p {
  color: #78350f;
}

.callout p:last-child,
.callout ul:last-child {
  margin-bottom: 0;
}

/* Kotak Latihan Soal Interaktif (Exercise Box) */
.exercise {
  margin-block: 1.8rem;
  padding: 1.6rem;
  border: 1px solid var(--line-strong);
  border-left: 0.4rem solid var(--blue-primary);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
}

.exercise h3 {
  margin-top: 0;
  margin-bottom: 0.75rem;
  color: var(--navy-deep);
}

.exercise-answer-toggle {
  margin-top: 1.35rem;
  border-top: 1px dashed var(--line);
  padding-top: 0.75rem;
}

summary {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  min-height: 2.75rem;
  padding: 0.55rem 1.15rem;
  border-radius: var(--radius-sm);
  background: var(--blue-subtle);
  border: 1px solid #bfdbfe;
  color: var(--blue-primary);
  cursor: pointer;
  font-weight: 700;
  font-size: 0.95rem;
  user-select: none;
  list-style: none;
  transition: all 0.15s ease;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  content: "";
  display: inline-block;
  width: 0.45rem;
  height: 0.45rem;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  transition: transform 0.2s ease;
}

details[open] summary::after {
  transform: rotate(-135deg);
}

details[open] summary {
  background: var(--blue-tint);
  border-color: var(--blue-primary);
  color: var(--blue-hover);
}

summary:hover {
  background: var(--blue-tint);
  color: var(--blue-hover);
}

.answer {
  padding-top: 1.15rem;
  padding-bottom: 0.5rem;
  color: var(--ink);
}

/* Kartu Navigasi Akhir Materi (Lesson Nav) */
.lesson-nav {
  margin-top: 3.5rem;
  padding: 1.75rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-card);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.25rem;
}

.lesson-nav h3 {
  margin: 0 0 0.25rem;
  font-size: 1.18rem;
}

.lesson-nav p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.lesson-nav__actions {
  display: flex;
  gap: 0.75rem;
}

/* ==========================================================================
   Footer Edukasi (Biru Gelap Akademik)
   ========================================================================== */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--navy-deep);
  color: #e2e8f0;
  padding-block: clamp(2.5rem, 5vw, 3.5rem) 1.5rem;
}

.site-footer__inner {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(12rem, 0.6fr);
  gap: 2.5rem;
  align-items: start;
}

.site-footer__brand {
  max-width: 32rem;
}

.site-footer__title {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-family: "Literata", Georgia, serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.65rem;
}

.site-footer__tagline {
  margin: 0;
  color: #94a3b8;
  font-size: 0.94rem;
  line-height: 1.6;
}

.site-footer__nav-title {
  margin: 0 0 0.6rem;
  color: var(--white);
  font-size: 0.84rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-footer__links {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.site-footer__links a {
  display: inline-flex;
  min-height: 2.25rem;
  align-items: center;
  color: #cbd5e1;
  font-size: 0.92rem;
  text-decoration: none;
  transition: color 0.15s ease;
}

.site-footer__links a:hover {
  color: #93c5fd;
  text-decoration: underline;
}

.site-footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  color: #94a3b8;
  font-size: 0.88rem;
}

.site-footer__bottom p {
  margin: 0;
}

.site-footer__disclaimer {
  color: #94a3b8;
}

.status-note {
  color: var(--ink-muted);
  font-size: 0.92rem;
  margin-top: 1rem;
}

/* ==========================================================================
   Tampilan Mobile & Responsif (Anti-Slop antislop-layoutmobile)
   ========================================================================== */
@media (max-width: 48rem) {
  .site-header__inner {
    min-height: 4.2rem;
  }

  .nav-toggle {
    display: none;
    align-items: center;
    justify-content: center;
  }

  body[data-js-ready="true"] .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: block;
    width: 100%;
    padding-bottom: 0.8rem;
  }

  body[data-js-ready="true"] .site-nav[data-open="false"] {
    display: none;
  }

  .site-nav[data-open="true"] {
    display: block;
  }

  .site-header__inner {
    flex-wrap: wrap;
  }

  .site-nav__list {
    display: grid;
    gap: 0.25rem;
    padding-top: 0.5rem;
    border-top: 1px solid var(--line);
  }

  .site-nav a {
    width: 100%;
    padding: 0.65rem 0.5rem;
  }

  .hero {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  h1 {
    font-size: clamp(2rem, 9vw, 3rem);
  }

  .concept-card__grid {
    grid-template-columns: 1fr;
  }

  .section-heading {
    display: block;
  }

  .section-heading .button {
    margin-top: 1rem;
  }

  .module-card__header {
    display: block;
  }

  .module-item {
    grid-template-columns: 1fr;
    gap: 0.75rem;
    padding: 1.25rem;
  }

  .module-item__number {
    width: 2.25rem;
    height: 2.25rem;
    font-size: 0.95rem;
  }

  .module-item .button {
    justify-self: start;
    width: 100%;
  }

  .page-intro--profile {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .page-intro__media {
    justify-content: flex-start;
  }

  .page-intro__img {
    height: 190px;
    max-width: 160px;
  }

  .teacher-card {
    grid-template-columns: 1fr;
    gap: 1.25rem;
    padding: 1.5rem;
    text-align: left;
  }

  .teacher-avatar {
    width: 3.8rem;
    height: 3.8rem;
    font-size: 1.2rem;
  }

  .teacher-avatar--img {
    width: 4.75rem;
    height: 4.75rem;
  }

  .teacher-card__figure {
    height: 95px;
    max-width: 80px;
  }

  .jump-nav {
    display: flex;
  }

  .content-layout {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .toc {
    display: none; /* Disembunyikan di mobile karena sudah ada jump-nav yang horizontal dan ringkas */
  }

  .lesson-nav {
    display: block;
  }

  .lesson-nav__actions {
    margin-top: 1.25rem;
    flex-direction: column;
  }

  .lesson-nav__actions .button {
    width: 100%;
  }

  .site-footer__inner {
    display: block;
  }

  .site-footer__inner p + p {
    margin-top: 0.5rem;
  }
}

/* Menghormati prefers-reduced-motion (Anti-Slop MOTION 1) */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ==========================================================================
   Tombol Cetak / Simpan PDF
   ========================================================================== */
.button--print {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--ink-soft);
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all 0.15s ease;
}

.button--print:hover {
  border-color: var(--blue-primary);
  color: var(--blue-primary);
  background: var(--blue-subtle);
}

.button--print svg {
  width: 0.95rem;
  height: 0.95rem;
}

/* Scrollbar halus untuk formula di layar sempit */
.formula {
  scrollbar-width: thin;
  scrollbar-color: #93c5fd transparent;
  -webkit-overflow-scrolling: touch;
}

.formula::-webkit-scrollbar {
  height: 5px;
}

.formula::-webkit-scrollbar-thumb {
  background: #93c5fd;
  border-radius: var(--radius-full);
}

/* ==========================================================================
   Format Cetak & Ekspor PDF (Print Stylesheet)
   ========================================================================== */
@media print {
  @page {
    margin: 1.5cm;
  }

  html,
  body {
    background: #ffffff !important;
    color: #000000 !important;
    font-size: 11pt;
    line-height: 1.5;
  }

  .site-header,
  .site-footer,
  .skip-link,
  .nav-toggle,
  .jump-nav,
  .toc,
  .lesson-nav,
  .button,
  .button--print,
  .no-print {
    display: none !important;
  }

  .content-layout {
    display: block !important;
  }

  .site-main {
    padding-block: 0 !important;
    width: 100% !important;
    max-width: none !important;
  }

  .article {
    max-width: 100% !important;
  }

  /* Tampilkan seluruh jawaban latihan saat dicetak */
  details {
    display: block !important;
    border-top: none !important;
    margin-top: 0.75rem !important;
  }

  summary {
    display: none !important;
  }

  .answer {
    display: block !important;
    padding: 0 !important;
  }

  .formula,
  .step-card,
  .exercise,
  .callout,
  .module-card {
    break-inside: avoid;
    page-break-inside: avoid;
    border-color: #cbd5e1 !important;
    background: #ffffff !important;
    box-shadow: none !important;
  }

  h1,
  h2,
  h3 {
    color: #000000 !important;
    break-after: avoid;
    page-break-after: avoid;
  }

  a {
    color: #000000 !important;
    text-decoration: underline;
  }
}