/* ==========================================================================
   DMF Vietnam — P07 V4.1: Editorial & Evidence-Grounded Course Page
   Kế thừa hệ thiết kế N16 / T05 (Roboto Condensed + Inter) của Trang chủ A V2.7
   và tinh thần bố cục Biên tập Đương đại của Concept V4.
   ========================================================================== */

:root {
  --ivory: #f8f6ef;
  --ivory-soft: #f2efe5;
  --sage-field: #eaeee1;
  --sage: #dce2d0;
  --sage-deep: #556e5f;
  --navy: #092b48;
  --ink: #16324a;
  --muted: #51646e;
  --blue: #0757b8;
  --blue-hover: #064899;
  --peach: #edb391;
  --peach-soft: #f3dfd1;
  --line: #d4dacb;
  --line-strong: #b9c3b2;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  color-scheme: light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  background: var(--ivory);
  color: var(--navy);
  font-family: Inter, system-ui, -apple-system, sans-serif;
  font-synthesis: none;
  scroll-behavior: smooth;
  scroll-padding-top: 148px;
}

body {
  margin: 0;
  background: var(--ivory);
  color: var(--navy);
  line-height: 1.6;
  overflow-x: clip;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
}

h1,
h2,
h3,
h4,
p,
dl,
dd,
figure,
ol,
ul {
  margin: 0;
}

h1,
h2,
h3,
h4 {
  font-family: 'Roboto Condensed', 'Arial Narrow', sans-serif;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--navy);
}

summary {
  list-style: none;
  cursor: pointer;
}

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

:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 4px;
}

[hidden] {
  display: none !important;
}

.container {
  width: min(1240px, calc(100% - 80px));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 20px;
  z-index: 200;
  padding: 12px 18px;
  background: #fff;
  color: var(--navy);
  border: 2px solid var(--blue);
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
}

.skip-link:focus {
  top: 16px;
}

/* --- Typography & Shared UI Controls --- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--sage-deep);
}

.small-line {
  width: 22px;
  height: 1px;
  background: currentColor;
}

.editorial-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 4px;
  background: var(--peach-soft);
  color: var(--navy);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.editorial-badge.sage {
  background: #dce3d1;
  color: #1f3c30;
}

.button {
  min-height: 52px;
  padding: 0 24px;
  border: 0;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  font-size: 14px;
  font-weight: 600;
  transition: background 0.22s var(--ease), transform 0.22s var(--ease),
    box-shadow 0.22s var(--ease);
}

.button.primary {
  background: var(--blue);
  color: #fff;
}

.button.primary:hover {
  background: var(--blue-hover);
  box-shadow: 0 8px 24px rgba(7, 87, 184, 0.22);
}

.button > span {
  font-size: 18px;
  line-height: 1;
  transition: transform 0.22s var(--ease);
}

.button:hover > span,
.button:focus-visible > span {
  transform: translate(2px, -2px);
}

.text-link {
  min-height: 44px;
  padding: 0;
  border: 0;
  background: none;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  font-weight: 600;
  color: var(--navy);
  position: relative;
}

.text-link::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 6px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0.32);
  transform-origin: left;
  transition: transform 0.24s var(--ease);
}

.text-link:hover,
.text-link:focus-visible {
  color: var(--blue);
}

.text-link:hover::after,
.text-link:focus-visible::after {
  transform: scaleX(1);
}

/* --- 1. Header --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  height: 84px;
  background: rgba(248, 246, 239, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
  transition: box-shadow 0.22s var(--ease);
}

.site-header.scrolled {
  box-shadow: 0 4px 20px rgba(9, 43, 72, 0.06);
}

.nav-wrap {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}

.brand {
  width: 128px;
  flex-shrink: 0;
  display: block;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  margin-left: auto;
  font-size: 13px;
  font-weight: 500;
}

.desktop-nav > a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  position: relative;
}

.desktop-nav > a[aria-current='page'] {
  color: var(--blue);
  font-weight: 600;
}

.desktop-nav > a:hover {
  color: var(--blue);
}

.nav-cta {
  min-height: 42px;
  padding: 0 18px;
  border: 1px solid var(--blue);
  border-radius: 999px;
  background: transparent;
  color: var(--blue);
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  font-weight: 600;
  transition: background 0.2s, color 0.2s;
}

.nav-cta:hover {
  background: var(--blue);
  color: #fff;
}

.mobile-nav {
  display: none;
}

/* --- 2. Hero Section (Concept V4 Asymmetric Organic Curve + Bloom) --- */
.course-hero {
  padding-top: 22px;
  padding-bottom: 44px;
}

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 20px;
  font-size: 12px;
  color: var(--muted);
}

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

.breadcrumb [aria-current='page'] {
  color: var(--navy);
  font-weight: 600;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1.08fr;
  gap: 48px;
  align-items: center;
}

.hero-copy {
  min-width: 0;
}

.hero-copy h1 {
  margin-top: 16px;
  font-size: clamp(54px, 5.3vw, 76px);
  line-height: 1.02;
  letter-spacing: -0.04em;
}

.hero-copy h1 > span {
  color: var(--blue);
}

.hero-subtitle {
  margin-top: 14px;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: clamp(28px, 2.7vw, 38px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--ink);
}

.hero-intro {
  margin-top: 16px;
  max-width: 490px;
  font-size: 16px;
  line-height: 1.72;
  color: var(--muted);
}

.hero-actions {
  margin-top: 26px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 18px 24px;
}

.hero-facts {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.hero-facts > div {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero-facts dt {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--sage-deep);
}

.hero-facts dd {
  font-size: 13px;
  font-weight: 600;
  color: var(--navy);
  line-height: 1.45;
}

.hero-art {
  position: relative;
  min-width: 0;
}

.hero-sage {
  position: absolute;
  inset: 16px -10px -12px 24px;
  background: #dfe5d3;
  border-radius: 44% 8% 12% 30% / 38% 8% 16% 24%;
  transform: rotate(1.5deg);
  pointer-events: none;
}

.hero-leaf {
  position: absolute;
  top: 14px;
  left: 16px;
  z-index: 3;
  width: 78px;
  height: 36px;
  background: var(--peach);
  border-radius: 100% 0 100% 0;
  transform: rotate(-26deg);
  pointer-events: none;
}

.hero-photo {
  position: relative;
  height: 460px;
  border-radius: 44% 6% 10% 30% / 38% 6% 14% 24%;
  overflow: hidden;
  background: #c8d2c0;
  isolation: isolate;
  box-shadow: 0 18px 44px rgba(9, 43, 72, 0.1);
}

.hero-photo img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 52% 38%;
  transition: transform 0.75s var(--ease), filter 0.6s var(--ease);
}

.hero-photo .hero-base-img {
  filter: grayscale(0.56) sepia(0.06) contrast(1.01);
}

.hero-photo .hero-color-wash {
  z-index: 1;
  -webkit-mask-image: radial-gradient(
    circle at 52% 45%,
    #000 0%,
    #000 52%,
    transparent 78%
  );
  mask-image: radial-gradient(
    circle at 52% 45%,
    #000 0%,
    #000 52%,
    transparent 78%
  );
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
  -webkit-mask-position: center;
  mask-position: center;
  -webkit-mask-size: 0% 0%;
  mask-size: 0% 0%;
  transition: -webkit-mask-size 1.6s var(--ease), mask-size 1.6s var(--ease),
    transform 0.75s var(--ease);
}

.hero-photo.is-bloomed .hero-color-wash,
.hero-art:hover .hero-photo .hero-color-wash,
.hero-art:focus-within .hero-photo .hero-color-wash {
  -webkit-mask-size: 320% 320%;
  mask-size: 320% 320%;
}

.hero-art:hover .hero-photo img {
  transform: scale(1.02);
}

.bloom-replay {
  position: absolute;
  right: 16px;
  bottom: 16px;
  z-index: 3;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.55);
  background: rgba(9, 43, 72, 0.68);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 16px;
  backdrop-filter: blur(6px);
  transition: background 0.2s, transform 0.25s var(--ease);
}

.bloom-replay:hover {
  background: var(--blue);
  transform: rotate(90deg);
}

.hero-art figcaption {
  position: absolute;
  left: 26px;
  bottom: 22px;
  right: 70px;
  z-index: 3;
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  max-width: 410px;
  padding: 12px 16px;
  border-radius: 6px;
  background: rgba(248, 246, 239, 0.95);
  box-shadow: 0 8px 24px rgba(9, 43, 72, 0.12);
  font-size: 12px;
  color: var(--navy);
}

.hero-art figcaption strong {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 16px;
  font-weight: 700;
  color: var(--blue);
  flex-shrink: 0;
}

.hero-art figcaption p {
  font-size: 12px;
  line-height: 1.45;
  color: var(--navy);
}

.hero-art figcaption small {
  font-size: 10px;
  color: var(--muted);
  white-space: nowrap;
}

/* --- 3. Sticky Section Bar + CEFR Level Pathway --- */
.course-navigation {
  position: sticky;
  top: 84px;
  z-index: 45;
  background: rgba(248, 246, 239, 0.96);
  backdrop-filter: blur(8px);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.course-nav-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 54px;
}

.course-toc {
  display: flex;
  align-items: center;
  gap: 26px;
}

.course-toc a {
  min-height: 54px;
  display: inline-flex;
  align-items: center;
  position: relative;
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  transition: color 0.2s;
}

.course-toc a:hover {
  color: var(--navy);
}

.course-toc a[aria-current='location'] {
  color: var(--blue);
  font-weight: 600;
}

.course-toc a[aria-current='location']::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2.5px;
  background: var(--blue);
}

.level-pathway {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
}

.level-pathway-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--muted);
  margin-right: 6px;
}

.level-pill {
  padding: 5px 11px;
  border-radius: 999px;
  border: 1px solid var(--line);
  font-size: 11.5px;
  font-weight: 600;
  color: var(--muted);
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}

.level-pill:hover {
  border-color: var(--blue);
  color: var(--blue);
}

.level-pill.is-active {
  background: var(--navy);
  border-color: var(--navy);
  color: var(--ivory);
}

.mobile-toc {
  display: none;
}

/* --- 4. Overview Strip (Compact Context Bridge) --- */
.overview-section {
  padding: 40px 0 36px;
  border-bottom: 1px solid var(--line);
}

.overview-strip-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 48px;
  align-items: start;
}

.overview-lead h2 {
  margin-top: 10px;
  font-size: clamp(34px, 3.2vw, 44px);
  line-height: 1.06;
}

.overview-lead h2 > span {
  color: var(--sage-deep);
}

.overview-lead > p {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 440px;
}

.overview-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.overview-card {
  padding: 22px 24px;
  border-radius: 8px;
  background: var(--ivory-soft);
  border: 1px solid var(--line);
}

.overview-card h3 {
  font-size: 22px;
  line-height: 1.15;
  margin-bottom: 10px;
}

.overview-card p {
  font-size: 13.5px;
  line-height: 1.68;
  color: var(--muted);
}

.quiet-list {
  padding-left: 18px;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
}

.quiet-list li + li {
  margin-top: 6px;
}

/* --- 5. Section 01: Cách DMF tổ chức việc học (V4 Editorial Photo + 3 Interactive Rows) --- */
.method-section {
  padding: 76px 0 80px;
  border-bottom: 1px solid var(--line);
}

.method-header {
  max-width: 680px;
  margin-bottom: 40px;
}

.method-header h2 {
  margin-top: 12px;
  font-size: clamp(44px, 4.2vw, 58px);
  line-height: 1.04;
}

.method-lead {
  margin-top: 12px;
  font-size: 18px;
  font-weight: 500;
  color: var(--ink);
}

.method-header .section-intro {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--muted);
}

.method-editorial-grid {
  display: grid;
  grid-template-columns: 1.12fr 0.88fr;
  gap: 52px;
  align-items: start;
}

.method-stage-visual {
  position: relative;
  border-radius: 8px 8px 8px 56px;
  overflow: hidden;
  background: #d8dfd0;
  min-height: 510px;
  box-shadow: 0 18px 42px rgba(9, 43, 72, 0.08);
  isolation: isolate;
}

.method-scene-frame {
  position: absolute;
  inset: 0;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.42s var(--ease), transform 0.55s var(--ease);
  transform: scale(1.015);
}

.method-scene-frame.is-active {
  opacity: 1;
  pointer-events: auto;
  transform: scale(1);
}

.method-scene-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 50% 42%;
}

.method-scene-shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(9, 43, 72, 0.04) 0%,
    rgba(9, 43, 72, 0.18) 48%,
    rgba(9, 43, 72, 0.9) 100%
  );
  pointer-events: none;
}

.method-scene-overlay {
  position: absolute;
  left: 28px;
  right: 28px;
  bottom: 26px;
  z-index: 2;
  color: var(--ivory);
}

.method-scene-top {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 14px;
}

.method-scene-number {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 56px;
  font-weight: 700;
  line-height: 0.95;
  color: rgba(255, 255, 255, 0.88);
}

.method-scene-meta {
  padding-left: 18px;
  border-left: 1px solid rgba(255, 255, 255, 0.35);
}

.method-scene-kicker {
  display: block;
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #d6e2d4;
}

.method-scene-title {
  margin-top: 4px;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 26px;
  font-weight: 700;
  line-height: 1.12;
  color: #fff;
}

.method-step-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.method-step-pill {
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(248, 246, 239, 0.16);
  border: 1px solid rgba(248, 246, 239, 0.32);
  backdrop-filter: blur(6px);
  font-size: 11.5px;
  font-weight: 500;
  color: #fff;
}

/* Right Column: 3 Interactive Editorial Rows */
.method-rows {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line-strong);
}

.method-row {
  border-bottom: 1px solid var(--line-strong);
  border-left: 3px solid transparent;
  transition: border-color 0.25s var(--ease), background 0.25s var(--ease);
}

.method-row.is-active {
  border-left-color: var(--blue);
  background: rgba(234, 238, 225, 0.45);
}

.method-row-trigger {
  width: 100%;
  padding: 20px 18px 20px 20px;
  border: 0;
  background: transparent;
  text-align: left;
  display: grid;
  grid-template-columns: 32px 1fr 28px;
  gap: 14px;
  align-items: start;
}

.method-row-num {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 20px;
  font-weight: 700;
  line-height: 1.25;
  color: var(--muted);
}

.method-row.is-active .method-row-num {
  color: var(--blue);
}

.method-row-head strong {
  display: block;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 27px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--navy);
}

.method-row-head span {
  display: block;
  margin-top: 6px;
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--muted);
}

.method-row-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  display: grid;
  place-items: center;
  font-size: 17px;
  line-height: 1;
  color: var(--navy);
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}

.method-row.is-active .method-row-icon {
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}

.method-row-body {
  padding: 0 20px 22px 66px;
}

.method-row-body > p {
  font-size: 14px;
  line-height: 1.72;
  color: var(--ink);
}

.method-points {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--line-strong);
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.method-points > div {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.method-points dt {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--sage-deep);
}

.method-points dd {
  font-size: 13px;
  line-height: 1.58;
  color: var(--muted);
}

.support-note {
  margin-top: 22px;
  padding: 16px 18px;
  border-radius: 8px;
  background: var(--ivory-soft);
  border: 1px solid var(--line);
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.support-note > span {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: #dce3d1;
  color: var(--navy);
  display: grid;
  place-items: center;
  font-size: 15px;
  flex-shrink: 0;
}

.support-note h3 {
  font-size: 18px;
  line-height: 1.2;
}

.support-note p {
  margin-top: 4px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* --- 6. Section 02: Nội dung & Đầu ra A1 (Split 4/8 + Notebook Photo + Accordion) --- */
.curriculum-section {
  padding: 76px 0 80px;
}

.curriculum-grid {
  display: grid;
  grid-template-columns: 0.84fr 1.16fr;
  gap: 56px;
  align-items: start;
}

.curriculum-rail h2 {
  margin-top: 14px;
  font-size: clamp(42px, 3.8vw, 54px);
  line-height: 1.04;
}

.curriculum-rail > .section-intro {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--muted);
}

.curriculum-notebook {
  margin-top: 24px;
  border-radius: 6px 40px 6px 6px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: #e5eadb;
}

.curriculum-notebook img {
  width: 100%;
  height: 215px;
  object-fit: cover;
  object-position: 50% 48%;
}

.curriculum-outcomes {
  margin-top: 20px;
  padding: 20px 22px;
  border-radius: 8px;
  background: var(--ivory-soft);
  border: 1px solid var(--line);
}

.curriculum-outcomes h3 {
  font-size: 20px;
  line-height: 1.2;
  margin-bottom: 12px;
}

.curriculum-outcomes ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.curriculum-outcomes li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 13px;
  line-height: 1.58;
  color: var(--ink);
}

.curriculum-outcomes li::before {
  content: '✓';
  font-weight: 700;
  color: var(--blue);
  flex-shrink: 0;
}

.curriculum-list {
  border-top: 1px solid var(--line-strong);
}

.curriculum-item {
  border-bottom: 1px solid var(--line-strong);
}

.curriculum-item summary {
  padding: 22px 8px 22px 0;
  display: grid;
  grid-template-columns: 36px 1fr 32px;
  gap: 14px;
  align-items: center;
  transition: color 0.2s;
}

.curriculum-item summary:hover .item-title {
  color: var(--blue);
}

.item-number {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 20px;
  font-weight: 700;
  color: var(--sage-deep);
}

.item-title {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 26px;
  font-weight: 700;
  line-height: 1.12;
  color: var(--navy);
}

.item-title small {
  font-family: Inter, sans-serif;
  font-size: 12.5px;
  font-weight: 500;
  color: var(--muted);
}

.expand-icon {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  display: grid;
  place-items: center;
  position: relative;
}

.expand-icon::before,
.expand-icon::after {
  content: '';
  position: absolute;
  background: var(--navy);
}

.expand-icon::before {
  width: 12px;
  height: 1.5px;
}

.expand-icon::after {
  width: 1.5px;
  height: 12px;
  transition: transform 0.2s;
}

details[open] > summary .expand-icon {
  background: var(--blue);
  border-color: var(--blue);
}

details[open] > summary .expand-icon::before {
  background: #fff;
}

details[open] > summary .expand-icon::after {
  transform: scaleY(0);
}

.disclosure-body {
  padding: 0 16px 24px 50px;
}

.disclosure-body > p {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--muted);
}

.topic-tags {
  margin-top: 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.topic-tags > span {
  padding: 5px 11px;
  border-radius: 999px;
  background: #e6ecdc;
  font-size: 12px;
  font-weight: 500;
  color: var(--navy);
}

.curriculum-footnote {
  margin-top: 18px;
  font-size: 13px;
  font-style: italic;
  color: var(--muted);
}

/* --- 7. Section 03: Thông tin lớp & Học phí (Tonal Sage Field) --- */
.decision-zone {
  background: var(--sage-field);
  padding: 76px 0 80px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.decision-grid {
  display: grid;
  grid-template-columns: 1.06fr 0.94fr;
  gap: 44px;
  align-items: start;
}

.schedule-section h2,
.fees-section h2 {
  margin-top: 12px;
  font-size: clamp(38px, 3.6vw, 50px);
  line-height: 1.05;
}

.schedule-section h2 > span,
.fees-section h2 > span {
  color: var(--sage-deep);
}

.schedule-section > .section-intro,
.fees-section > .section-intro {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--muted);
}

.mode-picker {
  margin-top: 24px;
}

.mode-picker > p {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--sage-deep);
  margin-bottom: 10px;
}

.mode-options {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.mode-options > button {
  min-height: 44px;
  padding: 0 20px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: var(--ivory);
  font-size: 13.5px;
  font-weight: 600;
  color: var(--navy);
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}

.mode-options > button:hover {
  border-color: var(--navy);
}

.mode-options > button[aria-pressed='true'] {
  background: var(--navy);
  border-color: var(--navy);
  color: var(--ivory);
}

.format-highlights {
  margin-top: 20px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.format-card {
  padding: 16px 18px;
  border-radius: 8px;
  background: rgba(248, 246, 239, 0.78);
  border: 1px solid var(--line);
  transition: border-color 0.2s, background 0.2s;
}

.format-card.is-selected {
  background: var(--ivory);
  border-color: var(--blue);
  box-shadow: 0 6px 20px rgba(7, 87, 184, 0.08);
}

.format-card h3 {
  font-size: 20px;
  line-height: 1.15;
}

.format-card p {
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.58;
  color: var(--muted);
}

.schedule-status {
  margin-top: 18px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink);
}

#schedule-content {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.schedule-empty {
  padding: 20px 22px;
  border-radius: 8px;
  background: var(--ivory);
  border: 1px solid var(--line);
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.calendar-icon {
  width: 38px;
  height: 38px;
  border-radius: 8px;
  background: #dce3d1;
  display: grid;
  grid-template-columns: repeat(2, 6px);
  place-content: center;
  gap: 4px;
  flex-shrink: 0;
}

.calendar-icon i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--navy);
  display: block;
}

.schedule-empty h3 {
  font-size: 22px;
  line-height: 1.15;
}

.schedule-empty p {
  margin-top: 4px;
  margin-bottom: 10px;
  font-size: 13.5px;
  color: var(--muted);
}

.scenario-notice {
  padding: 10px 14px;
  border-radius: 6px;
  background: var(--peach-soft);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.intake-card {
  padding: 18px 20px;
  border-radius: 8px;
  background: var(--ivory);
  border: 1px solid var(--line-strong);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.intake-card h3 {
  font-size: 22px;
}

.intake-meta {
  font-size: 12px;
  color: var(--muted);
}

.intake-select {
  margin-top: 8px;
  align-self: flex-start;
  min-height: 40px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid var(--blue);
  background: transparent;
  color: var(--blue);
  font-size: 13px;
  font-weight: 600;
}

.intake-select[aria-pressed='true'] {
  background: var(--blue);
  color: #fff;
}

.intake-change {
  padding: 16px 18px;
  border-radius: 8px;
  background: #fff4ec;
  border: 1px solid var(--peach);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.selection-summary {
  margin-top: 16px;
  padding: 12px 16px;
  border-left: 3px solid var(--blue);
  background: rgba(248, 246, 239, 0.72);
  font-size: 13px;
  font-weight: 500;
  color: var(--navy);
}

/* Fee Panel (Right Column of Decision Zone) */
.fee-panel {
  margin-top: 24px;
  padding: 28px 30px;
  border-radius: 10px;
  background: var(--ivory);
  border: 1px solid var(--line-strong);
  box-shadow: 0 12px 32px rgba(9, 43, 72, 0.05);
}

.fee-panel-head span {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--sage-deep);
}

.fee-panel-head h3 {
  margin-top: 6px;
  font-size: 30px;
  line-height: 1.1;
}

.fee-panel-head p {
  margin-top: 6px;
  font-size: 13.5px;
  color: var(--muted);
}

.fee-facts-list {
  margin-top: 20px;
  margin-bottom: 20px;
  border-top: 1px solid var(--line);
}

.fee-facts-list > div {
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  display: grid;
  grid-template-columns: 155px 1fr;
  gap: 16px;
  align-items: baseline;
}

.fee-facts-list dt {
  font-size: 13px;
  font-weight: 600;
  color: var(--navy);
}

.fee-facts-list dd {
  font-size: 13px;
  line-height: 1.58;
  color: var(--muted);
}

/* --- 8. Section 04: Giải đáp trước khi bắt đầu (FAQ) --- */
.faq-section {
  padding: 76px 0 84px;
}

.faq-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 56px;
  align-items: start;
}

.faq-rail h2 {
  margin-top: 12px;
  font-size: clamp(40px, 3.8vw, 52px);
  line-height: 1.04;
}

.faq-rail h2 > span {
  color: var(--sage-deep);
}

.faq-rail > p {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--muted);
}

.faq-direct-box {
  margin-top: 24px;
  padding: 20px 22px;
  border-radius: 8px;
  background: var(--ivory-soft);
  border: 1px solid var(--line);
}

.faq-direct-box h3 {
  font-size: 21px;
  line-height: 1.2;
}

.faq-direct-box p {
  margin-top: 6px;
  margin-bottom: 14px;
  font-size: 13px;
  color: var(--muted);
}

.faq-list {
  border-top: 1px solid var(--line-strong);
}

.faq-list details {
  border-bottom: 1px solid var(--line-strong);
}

.faq-list summary {
  padding: 20px 4px 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 24px;
  font-weight: 700;
  line-height: 1.18;
  color: var(--navy);
  transition: color 0.2s;
}

.faq-list summary:hover {
  color: var(--blue);
}

.faq-answer {
  padding: 0 24px 22px 0;
}

.faq-answer p {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--muted);
}

/* --- 9. Closing CTA & Footer (with CLM-001 Contact Strip) --- */
.closing-section {
  background: var(--navy);
  color: var(--ivory);
  padding: 68px 0;
}

.closing-grid {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
}

.closing-grid .eyebrow {
  color: #c7d5c8;
}

.closing-grid h2 {
  margin-top: 12px;
  font-size: clamp(44px, 4.4vw, 62px);
  line-height: 1.03;
  color: var(--ivory);
}

.closing-grid h2 > span {
  color: #dbe3c9;
}

.closing-action {
  max-width: 380px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 18px;
}

.closing-action p {
  font-size: 14.5px;
  line-height: 1.68;
  color: #d2dee4;
}

.site-footer {
  background: var(--ivory);
  padding: 52px 0 28px;
  border-top: 1px solid var(--line);
}

.footer-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 28px;
  padding-bottom: 28px;
}

.footer-main > p {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 28px;
  font-weight: 700;
  line-height: 1.1;
}

.footer-main > p > span {
  color: var(--sage-deep);
}

.footer-main nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 24px;
  font-size: 13px;
  font-weight: 500;
}

.footer-main nav a:hover {
  color: var(--blue);
}

.back-top {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  display: grid;
  place-items: center;
  font-size: 18px;
  transition: background 0.2s;
}

.back-top:hover {
  background: var(--sage);
}

.footer-contact-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px 28px;
  padding: 22px 0;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
}

.footer-contact-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer-contact-item > span {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--sage-deep);
}

.footer-contact-item > a,
.footer-contact-item > strong {
  font-weight: 600;
  color: var(--navy);
}

.footer-contact-item > a:hover {
  color: var(--blue);
  text-decoration: underline;
}

.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 11px;
  color: var(--muted);
}

/* --- 10. Mobile Sticky CTA & Consultation Dialog --- */
.mobile-cta {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 55;
  padding: 12px 20px calc(12px + env(safe-area-inset-bottom));
  background: rgba(248, 246, 239, 0.96);
  backdrop-filter: blur(10px);
  border-top: 1px solid var(--line-strong);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  box-shadow: 0 -8px 24px rgba(9, 43, 72, 0.08);
}

.mobile-cta > div {
  display: flex;
  flex-direction: column;
}

.mobile-cta > div span {
  font-size: 11px;
  color: var(--muted);
}

.mobile-cta > div strong {
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 22px;
  line-height: 1.1;
}

.course-dialog {
  border: 0;
  border-radius: 12px;
  padding: 38px 36px;
  background: var(--ivory);
  color: var(--navy);
  width: min(540px, calc(100% - 32px));
  max-height: 90dvh;
  overflow: auto;
  box-shadow: 0 24px 60px rgba(9, 43, 72, 0.25);
}

.course-dialog::backdrop {
  background: rgba(6, 30, 53, 0.68);
  backdrop-filter: blur(5px);
}

.dialog-close {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 42px;
  height: 42px;
  border: 0;
  background: transparent;
  font-size: 28px;
}

.course-dialog h2 {
  margin: 12px 0 14px;
  font-size: 44px;
  line-height: 1.04;
}

.course-dialog h2 > span {
  color: var(--blue);
}

.dialog-context {
  padding: 10px 14px;
  border-radius: 6px;
  background: #e6ecdc;
  font-size: 13px;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 12px;
}

.demo-notice {
  font-size: 12px;
  line-height: 1.55;
  color: var(--muted);
  border-left: 2px solid var(--sage-deep);
  padding-left: 12px;
  margin-bottom: 18px;
}

.course-dialog form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.course-dialog label {
  margin-top: 8px;
  font-size: 12.5px;
  font-weight: 600;
}

.course-dialog select,
.course-dialog textarea {
  width: 100%;
  min-height: 46px;
  padding: 11px 13px;
  border-radius: 6px;
  border: 1px solid var(--line-strong);
  background: #fff;
  font-size: 14px;
}

.course-dialog textarea {
  min-height: 104px;
  resize: vertical;
}

.course-dialog form .button {
  margin-top: 14px;
}

.result-label {
  margin-bottom: 10px;
}

[data-result-body] {
  white-space: pre-wrap;
  padding: 16px;
  border-radius: 8px;
  background: #fff;
  border: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.68;
  margin-bottom: 16px;
}

.consult-direct-contact {
  margin-bottom: 16px;
  padding: 12px 14px;
  border-radius: 6px;
  background: #eaeee1;
  font-size: 12.5px;
  line-height: 1.58;
}

.consult-direct-contact a {
  color: var(--blue);
  font-weight: 600;
  text-decoration: underline;
}

.not-found {
  padding: 96px 0;
}

.not-found h1 {
  margin: 14px 0 16px;
  font-size: clamp(44px, 5vw, 68px);
  line-height: 1.04;
}

.not-found p {
  margin-bottom: 24px;
  font-size: 16px;
  color: var(--muted);
}

/* --- 11. Responsive Breakpoints (Tablet & Mobile) --- */
@media (max-width: 1199px) {
  .container {
    width: calc(100% - 56px);
  }
  .hero-grid {
    gap: 32px;
  }
  .hero-photo {
    height: 410px;
  }
  .method-editorial-grid,
  .curriculum-grid,
  .decision-grid,
  .faq-grid,
  .overview-strip-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .method-stage-visual {
    min-height: 400px;
  }
  .level-pathway-label {
    display: none;
  }
  .footer-contact-strip {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 767px) {
  html {
    scroll-padding-top: 132px;
  }
  .container {
    width: calc(100% - 36px);
  }
  .site-header {
    height: 72px;
  }
  .brand {
    width: 108px;
  }
  .desktop-nav,
  .nav-cta {
    display: none;
  }
  .nav-wrap {
    justify-content: space-between;
  }
  .mobile-nav {
    display: block;
  }
  .mobile-nav > summary {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--line-strong);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 6px;
  }
  .mobile-nav > summary > span {
    width: 16px;
    height: 1.5px;
    background: var(--navy);
    transition: transform 0.22s;
  }
  .mobile-nav[open] > summary > span:first-child {
    transform: translateY(3.75px) rotate(45deg);
  }
  .mobile-nav[open] > summary > span:last-child {
    transform: translateY(-3.75px) rotate(-45deg);
  }
  .mobile-nav nav {
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    padding: 18px 20px 22px;
    background: var(--ivory);
    border-bottom: 1px solid var(--line-strong);
    box-shadow: 0 18px 32px rgba(9, 43, 72, 0.12);
    display: flex;
    flex-direction: column;
    gap: 4px;
  }
  .mobile-nav nav a,
  .mobile-nav nav button {
    min-height: 48px;
    padding: 8px 0;
    border: 0;
    border-bottom: 1px solid var(--line);
    background: none;
    text-align: left;
    font-family: 'Roboto Condensed', sans-serif;
    font-size: 24px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }
  .course-hero {
    padding-top: 16px;
    padding-bottom: 32px;
  }
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .hero-facts {
    grid-template-columns: 1fr;
    gap: 12px;
  }
  .hero-photo {
    height: 290px;
    border-radius: 32% 6% 10% 20% / 28% 6% 12% 18%;
  }
  .hero-photo .hero-base-img {
    filter: none;
  }
  .hero-art figcaption {
    left: 14px;
    right: 60px;
    bottom: 14px;
    padding: 10px 12px;
  }
  .course-navigation {
    top: 72px;
  }
  .course-nav-bar {
    display: none;
  }
  .mobile-toc {
    display: block;
    position: relative;
  }
  .mobile-toc > summary {
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 13px;
    font-weight: 600;
  }
  .mobile-toc nav {
    padding: 8px 0 16px;
    border-top: 1px solid var(--line);
    display: flex;
    flex-direction: column;
    gap: 4px;
  }
  .mobile-toc nav a {
    min-height: 40px;
    display: flex;
    align-items: center;
    font-size: 14px;
    font-weight: 500;
  }
  .overview-columns,
  .format-highlights {
    grid-template-columns: 1fr;
  }
  .method-section,
  .curriculum-section,
  .decision-zone,
  .faq-section {
    padding: 48px 0 52px;
  }
  .method-stage-visual {
    min-height: 320px;
    border-radius: 6px 6px 6px 36px;
  }
  .method-scene-overlay {
    left: 18px;
    right: 18px;
    bottom: 18px;
  }
  .method-scene-number {
    font-size: 42px;
  }
  .method-scene-title {
    font-size: 21px;
  }
  .method-row-body {
    padding: 0 14px 18px 20px;
  }
  .disclosure-body {
    padding: 0 8px 20px 0;
  }
  .fee-panel {
    padding: 22px 20px;
  }
  .fee-facts-list > div {
    grid-template-columns: 1fr;
    gap: 4px;
  }
  .closing-grid {
    flex-direction: column;
    align-items: flex-start;
  }
  .footer-contact-strip {
    grid-template-columns: 1fr;
  }
  html.has-mobile-cta body {
    padding-bottom: 84px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
  .hero-photo .hero-base-img {
    filter: none !important;
  }
}

html.reduce-motion *,
html.reduce-motion *::before,
html.reduce-motion *::after {
  animation: none !important;
  transition: none !important;
  scroll-behavior: auto !important;
}

html.reduce-motion .hero-photo .hero-base-img {
  filter: none !important;
}