/* QC3 Design Spec: brand roles are separate from response-state roles. */
:root {
  --ink: #15343e;
  --teal: #0b7771;
  --sun: #f2b84b;
  --coral: #e56b55;
  --mist: #e6f2ef;
  --paper: #f7faf8;
  --white: #fff;
  --text-secondary: #49616b;
  --border-subtle: rgb(21 52 62 / 15%);
  --border-control: #7a8e96;
  --action-hover: #09655f;
  --selected-surface: #eef8f5;
  --correct: #176744;
  --correct-surface: #e7f5f0;
  --incorrect: #9c3d2e;
  --incorrect-surface: #fff1ed;
  --unknown: #49616b;
  --unknown-border: #6b7f87;
  --unknown-surface: #f0f4f5;
  --warning: #76520e;
  --warning-surface: #fff6de;
  --disabled-text: #586c74;
  --disabled-surface: #e8eef0;
  --font-body: 'Hiragino Sans', 'Yu Gothic', YuGothic, Meiryo, sans-serif;
  --font-brand: 'Hiragino Kaku Gothic StdN', 'Yu Gothic', YuGothic, Meiryo, sans-serif;
  --font-serif: 'Yu Mincho', YuMincho, 'Hiragino Mincho ProN', serif;
  --font-latin: 'Avenir Next', 'Helvetica Neue', Arial, sans-serif;
  --radius-surface: 18px 5px 18px 5px;
  --shadow-entry: 0 8px 24px rgb(21 52 62 / 6%);
  color: var(--ink);
  background: var(--paper);
  font-family: var(--font-body);
  font-size: 100%;
  font-synthesis: none;
  line-height: 1.8;
}

* { box-sizing: border-box; }
body { margin: 0; font-size: 1.125rem; }
button, input { font: inherit; }
button, a, input, summary { touch-action: manipulation; }
a { color: var(--teal); text-underline-offset: .2em; }
a:hover { color: var(--action-hover); }
h1, h2, h3, p { margin: 0 0 1rem; overflow-wrap: anywhere; }
h1 { font-size: 2rem; line-height: 1.5; letter-spacing: .025em; }
h2 { font-size: 1.375rem; line-height: 1.6; }
h3 { font-size: 1.125rem; line-height: 1.65; }
:focus-visible { outline: 3px solid var(--ink); outline-offset: 4px; box-shadow: 0 0 0 2px var(--white); }
[hidden] { display: none !important; }
.page { width: calc(100% - 48px); max-width: 1180px; margin: 48px auto; }
.page.learning { max-width: 800px; margin-top: 24px; }
.page.result-page { max-width: 960px; }
.page.hub-page { max-width: 960px; }
.surface { min-width: 0; background: var(--white); padding: 32px; border: 1px solid var(--border-subtle); border-radius: var(--radius-surface); margin: 24px 0; }
.lead { font-size: 1.125rem; color: var(--text-secondary); margin-bottom: 32px; }
.eyebrow { color: var(--teal); font-family: var(--font-latin); font-size: .875rem; letter-spacing: .16em; font-weight: 700; }
.muted { color: var(--text-secondary); font-size: .875rem; line-height: 1.7; }
.skip-link { position: absolute; top: -120px; left: 16px; background: var(--white); padding: 12px; z-index: 10; }
.skip-link:focus { top: 8px; }
.save-status { display: block; width: calc(100% - 48px); max-width: 1180px; margin: auto; text-align: right; color: var(--text-secondary); font-size: .875rem; }
.save-status:empty { display: none; }
.notice, .error { border: 1px solid var(--warning); background: var(--warning-surface); color: var(--warning); padding: 20px; border-radius: 8px; margin: 20px 0; }
.error { width: calc(100% - 32px); max-width: 800px; margin: 24px auto; }
.error .button { margin-top: 16px; }
.course-tagline { font-family: var(--font-serif); font-size: 1.375rem; }
.course-overview { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); gap: 48px; align-items: stretch; margin: 32px 0; }
.course-introduction { padding: 24px 0; }
.course-introduction > p:not(.course-chip) { max-width: 34em; }
.course-introduction .text-action { margin-left: 20px; }
.foundation-entry.surface { margin: 0; background: var(--mist); box-shadow: var(--shadow-entry); }
.foundation-entry p:not(.eyebrow) { font-size: 1rem; }
.foundation-entry .button { width: 100%; }
.resume-card { border-left: 4px solid var(--teal); background: var(--white); box-shadow: var(--shadow-entry); }
.resume-card h2 { margin-bottom: 8px; }
.unit-surface { scroll-margin-top: 24px; }
.unit-list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; margin-top: 32px; }
.unit { display: flex; flex-direction: column; align-items: flex-start; border: 1px solid var(--border-subtle); border-radius: 12px 4px 12px 4px; padding: 24px; scroll-margin-top: 24px; min-width: 0; }
.unit-number { font-family: var(--font-latin); color: var(--teal); font-size: .875rem; font-weight: 700; letter-spacing: .1em; margin-bottom: 12px; }
.unit h3 { margin-bottom: 8px; }
.unit .button { margin-top: auto; width: 100%; }
.history-row, .drill-entry { padding: 24px 0; border-bottom: 1px solid var(--border-subtle); }
.history-row:last-child, .drill-entry:last-child { border-bottom: 0; padding-bottom: 0; }
.history-row h3 { margin-bottom: 8px; }
.group-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.group-link { display: flex; align-items: center; min-height: 52px; padding: 20px; border: 1px solid var(--border-control); border-radius: 12px 4px 12px 4px; background: var(--white); overflow-wrap: anywhere; font-size: 1rem; }
.group-link:hover { background: var(--mist); }
.drill-entry h2 { color: var(--teal); font-size: 1rem; }
.drill-entry > .button { margin-top: 8px; }
@media (max-width: 1023px) {
  .unit-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course-overview { gap: 24px; }
}
@media (max-width: 639px) {
  .page { width: calc(100% - 32px); margin: 32px auto; }
  .surface { padding: 16px; }
  h1 { font-size: 1.625rem; }
  h2 { font-size: 1.25rem; }
  .course-overview, .unit-list, .group-list { grid-template-columns: minmax(0, 1fr); }
  .course-overview { margin-top: 24px; gap: 20px; }
  .course-introduction { padding: 0; }
  .course-introduction .text-action { margin: 8px 0 0; }
  .unit-list { gap: 16px; margin-top: 24px; }
  .unit { padding: 16px; }
  .unit-number { margin-bottom: 8px; }
  .save-status { width: calc(100% - 32px); }
}
@media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; } }

/* WO028 unit start screen: session size / review entry points for one unit. */
.page.unit-start-page { max-width: 800px; }
.unit-weak { margin-bottom: 12px; color: var(--warning); font-size: .875rem; font-weight: 700; line-height: 1.7; }
.unit-start-intro { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 24px; }
.unit-start-total { margin: 0; font-family: var(--font-latin), var(--font-body); font-size: 1.125rem; font-weight: 700; }
.unit-start-resume .button { margin-top: 8px; }
.unit-start-resume p:last-child { margin-bottom: 0; }
.unit-start-weak { font-weight: 700; color: var(--warning); }
.start-actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 24px 0 16px; }
.start-actions .button { flex: 0 1 auto; }
.unit-start-review p:last-child { margin-bottom: 0; }
@media (max-width: 639px) {
  .unit-start-intro { justify-content: flex-start; }
  .start-actions { flex-direction: column; gap: 12px; }
}

/* WO031 course-wide review inside the 分野別演習 surface. Existing surfaces / actions reused. */
.course-review { margin: 24px 0 0; }
.course-review h3 { margin-bottom: 8px; }
.course-review h4 { margin: 24px 0 8px; font-size: 1rem; }
.course-review .start-actions { margin: 12px 0; }
.course-review p:last-child { margin-bottom: 0; }
.course-review-reset { margin-top: 16px; }
.course-review-confirm .start-actions { margin-bottom: 0; }
.course-review-confirm p:last-child { margin-bottom: 12px; }

/* WO033 admin question identity — local development only; absent from production builds. */
.admin-info { margin-top: 1.5rem; padding: 0.75rem 1rem; border: 1px dashed var(--line, #c8ccd4); border-radius: 8px; }
.admin-info summary { cursor: pointer; font-weight: 600; }
.admin-info-row { display: flex; flex-wrap: wrap; gap: 0.25rem 0.75rem; padding: 0.15rem 0; }
.admin-info-label { min-width: 8rem; font-size: 0.85rem; opacity: 0.75; }
.admin-info-value { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; word-break: break-all; }
.admin-info-actions { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 0.75rem; }

/* The final reference's composition and geometry; all surfaces are live DOM/CSS. */
.site-header { background: var(--paper); }
/* WO043: the row wraps at every width, and the account area is the part that moves to a second
   line. The lockup and the navigation do not shrink, so a long email address can never squash the
   brand into a column or stack the nav. (`.exercise-header .header-inner` is a grid: unaffected.) */
.header-inner { width: calc(100% - 48px); max-width: 1180px; margin: auto; min-height: 80px; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 24px; border-bottom: 1px solid var(--border-subtle); padding: 12px 0; }
.brand { display: inline-flex; flex-shrink: 0; margin-right: auto; align-items: center; gap: 10px; min-width: 0; color: var(--ink); text-decoration: none; min-height: 44px; }
.brand:hover { color: var(--ink); }
/* Let the glyph's intrinsic size grow the background during text-only zoom. */
.brand-mark { display: grid; place-items: center; position: relative; width: auto; height: auto; min-width: 34px; min-height: 34px; padding: 5px; flex-shrink: 0; border-radius: 9px 9px 3px 9px; color: var(--white); background: var(--teal); font: 700 24px/1 var(--font-serif); }
.brand-mark::after { content: ''; width: 7px; height: 7px; border-radius: 50%; background: var(--sun); position: absolute; right: -3px; top: -3px; }
.brand-names { min-width: 0; overflow-wrap: anywhere; display: flex; flex-direction: column; }
.brand-name { font-family: var(--font-brand); font-size: 1.25rem; font-weight: 900; line-height: 1.25; letter-spacing: .06em; }
.brand-en { font-family: var(--font-latin); font-size: .75rem; font-weight: 700; line-height: 1.4; letter-spacing: .15em; }
.header-inner nav { display: flex; flex-shrink: 0; align-items: center; flex-wrap: wrap; justify-content: flex-end; gap: 24px; }
.nav-link { display: inline-flex; align-items: center; min-height: 44px; font-size: .9375rem; font-weight: 700; color: var(--ink); text-decoration: none; }
.nav-link:hover { text-decoration: underline; color: var(--teal); }
/* Course Navigation: one extra, quieter row below the Global Header (product IA v1 §4). */
.course-bar { background: var(--mist); border-bottom: 1px solid var(--border-subtle); }
.course-bar-inner { width: calc(100% - 48px); max-width: 1180px; margin: auto; }
.course-nav { display: flex; align-items: center; flex-wrap: wrap; gap: 0 20px; min-width: 0; padding: 2px 0; }
.course-nav-name { display: inline-flex; align-items: center; min-height: 44px; padding-right: 20px; border-right: 1px solid var(--border-subtle); font-size: .9375rem; font-weight: 700; color: var(--ink); text-decoration: none; }
.course-nav-name:hover { color: var(--teal); text-decoration: underline; }
.course-nav-link { display: inline-flex; align-items: center; min-height: 44px; font-size: .875rem; font-weight: 700; color: var(--text-secondary); text-decoration: none; }
.course-nav-link:hover { color: var(--teal); text-decoration: underline; }
/* Top course section and /courses share one card component and one grid. */
.home-courses { background: var(--paper); border-top: 1px solid var(--border-subtle); }
.home-courses-inner { width: calc(100% - 48px); max-width: 1180px; margin: auto; padding: 44px 0 52px; }
.home-courses-inner > .eyebrow { margin-bottom: 6px; }
.home-courses-lead { margin-bottom: 24px; }
.page.courses-page { max-width: 1180px; }
.courses-page > .eyebrow { margin-bottom: 6px; }
.course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 320px), 1fr)); gap: 24px; }
.course-card.surface { display: flex; flex-direction: column; align-items: flex-start; margin: 0; padding: 28px; box-shadow: var(--shadow-entry); }
.course-card-field { font: 700 .75rem/1.5 var(--font-latin); letter-spacing: .12em; color: var(--teal); margin-bottom: 8px; }
.course-card-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px; width: 100%; }
.course-card-name { font-size: 1.25rem; margin: 0; }
.course-status { display: inline-flex; align-items: center; padding: 3px 12px; border-radius: 30px; background: var(--mist); color: var(--teal); font-size: .875rem; font-weight: 700; line-height: 1.6; }
.course-card-lead { font-size: .9375rem; margin: 12px 0 22px; }
.course-card .button { margin-top: auto; width: 100%; }
.home { margin: 0; }
.hero { width: calc(100% - 48px); max-width: 1180px; margin: auto; padding: 54px 0 58px; display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); align-items: center; gap: 64px; position: relative; isolation: isolate; }
.hero::before { content: 'TOKINASU'; position: absolute; z-index: -1; inset: 20px 0 auto; overflow: hidden; color: rgb(11 119 113 / 3.5%); font: 900 clamp(5rem, 13vw, 12rem)/1 var(--font-latin); letter-spacing: .08em; pointer-events: none; }
.hero-intro, .hero-experience { min-width: 0; }
.hero-eyebrow { font: 800 .75rem/1.5 var(--font-latin); letter-spacing: .27em; color: var(--teal); margin-bottom: 8px; }
.hero-title { font-family: var(--font-brand); font-weight: 900; font-size: clamp(3.5rem, 5.7vw, 5.125rem); line-height: 1.2; letter-spacing: .015em; margin-bottom: 18px; }
.hero-tagline { font-family: var(--font-serif); font-size: clamp(1.75rem, 2.4vw, 2.125rem); font-weight: 700; line-height: 1.6; letter-spacing: .035em; margin-bottom: 12px; }
.wordplay { display: flex; align-items: center; gap: 12px; width: fit-content; font-family: var(--font-serif); font-size: .875rem; color: var(--teal); margin-bottom: 24px; }
.wordplay-line { display: flex; gap: 9px; align-items: center; color: var(--text-secondary); }
.wordplay-line::before, .wordplay-line::after { content: ''; width: 20px; height: 1px; background: var(--border-control); }
.hero .course-chip { margin-bottom: 18px; }
.hero-lead { white-space: pre-line; font-size: .9375rem; line-height: 2; margin-bottom: 24px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-actions .button { padding-inline: 19px; }
.hero-note { color: var(--text-secondary); font-size: .875rem; line-height: 1.7; margin: 12px 0 0; }
.brand-route { position: relative; width: calc(100% - 56px); max-width: 100%; margin: 0 auto -10px; z-index: 1; }
.route-symbols { display: flex; align-items: center; gap: 6px; }
.route-mark { display: grid; place-items: center; width: 43px; height: 43px; flex-shrink: 0; border: 4px solid var(--paper); box-sizing: content-box; border-radius: 10px 10px 3px 10px; font: 700 30px/1 var(--font-serif); }
.route-understand { background: var(--teal); color: var(--white); }
.route-solve { background: var(--sun); color: var(--ink); }
.route-line { height: 2px; flex: 1; background: linear-gradient(90deg, var(--teal), var(--sun)); position: relative; }
.route-line::before, .route-line::after { content: ''; position: absolute; top: -3px; width: 8px; height: 8px; border-radius: 50%; }
.route-line::before { left: 18%; background: var(--teal); }
.route-line::after { right: 18%; background: var(--sun); }
.route-caption { width: 100%; font: 700 .75rem/1.5 var(--font-latin); letter-spacing: .12em; text-align: center; margin: 0 0 6px; color: var(--teal); }
.experience-card { position: relative; background: var(--white); border: 1px solid var(--border-subtle); border-radius: var(--radius-surface); padding: 26px; box-shadow: var(--shadow-entry); }
.experience-card::before { content: ''; position: absolute; inset: 12px -12px -12px 12px; background: var(--mist); border-radius: var(--radius-surface); z-index: -1; }
.experience-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px; border-bottom: 1px solid var(--border-subtle); margin-bottom: 16px; padding-bottom: 12px; }
.experience-head > div { min-width: 0; }
.experience-head h2 { font-size: 1.1875rem; margin: 4px 0 0; }
.experience-head .eyebrow { font-size: .75rem; letter-spacing: .12em; margin: 0; }
.preview-label { font-size: .875rem; color: var(--teal); background: var(--mist); border-radius: 30px; padding: 3px 12px; }
.experience-card > h2 { font-size: 1.1875rem; margin-bottom: 18px; }
.experience-question { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); gap: 12px; align-items: center; position: relative; background: var(--paper); border: 1px solid var(--border-subtle); border-radius: 8px; padding: 12px 16px 12px 54px; }
.experience-question .step-number { position: absolute; left: 16px; top: 16px; }
.experience-card h3 { font-size: 1rem; margin-bottom: 4px; }
.experience-card p:not(.eyebrow):not(.preview-note) { font-size: .875rem; white-space: pre-line; line-height: 1.8; margin-bottom: 0; }
.step-number { font: 700 .875rem/1.5 var(--font-latin); color: var(--teal); }
.experience-path { margin: 0; padding: 0; list-style: none; }
.experience-path li { display: flex; gap: 18px; align-items: flex-start; padding: 12px 0; border-bottom: 1px solid var(--border-subtle); }
.experience-path .step-number { padding-top: 3px; }
.experience-path li > div { min-width: 0; flex: 1; display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.45fr); gap: 12px; }
.experience-path h3 { margin: 0; }
.experience-return { display: flex; gap: 12px; padding: 14px; background: var(--incorrect-surface); border-left: 3px solid var(--coral); border-radius: 4px; margin-top: 16px; }
.experience-return > div { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr); gap: 12px; align-items: center; min-width: 0; flex: 1; }
.experience-return h3 { font-size: .9375rem; margin: 0; }
.return-symbol { color: var(--incorrect); font-size: 1.5rem; }
.preview-note { font-size: .875rem; color: var(--text-secondary); line-height: 1.7; margin: 14px 0 0; }
.method-band { background: var(--ink); color: var(--white); }
.method-inner { width: calc(100% - 48px); max-width: 1180px; margin: auto; padding: 26px 0; display: grid; grid-template-columns: 200px repeat(4, minmax(0, 1fr)); align-items: center; }
.method-inner > h2 { font: 700 1.125rem/1.7 var(--font-serif); white-space: pre-line; margin: 0; }
.method-step { border-left: 1px solid rgb(255 255 255 / 20%); padding: 0 20px; position: relative; }
.method-step::before { content: ''; position: absolute; top: 0; left: -3px; width: 5px; height: 5px; border-radius: 50%; background: var(--sun); }
.method-step > span { font: 700 .75rem/1.5 var(--font-latin); letter-spacing: .14em; color: #a8d9ce; }
.method-step h3 { margin: 6px 0; font-size: .9375rem; }
.method-step p { color: #d3e2e4; font-size: .875rem; margin: 0; }
.footer { border-top: 1px solid var(--border-subtle); margin-top: 48px; color: var(--text-secondary); font-size: .875rem; line-height: 1.8; }
.home + .footer { margin-top: 0; border: 0; }
.footer-inner { width: calc(100% - 48px); max-width: 1180px; margin: auto; padding: 28px 0; }
.footer p { margin-bottom: 8px; }
.footer-brand { font-family: var(--font-latin); font-size: .75rem; font-weight: 700; letter-spacing: .2em; color: var(--teal); }
.course-notice { max-width: 62em; }
.storage-note { margin-top: 16px; }
/* Local trial entries share the existing course cards; no second grade selector.
   The same container and gutter apply to both the hero and its destination. */
.home.trial-local { --trial-content-width: 1180px; --trial-gutters: 48px; }
.trial-local .hero, .trial-local .home-courses-inner { width: calc(100% - var(--trial-gutters)); max-width: var(--trial-content-width); }
.trial-local .hero-actions { flex-direction: column; align-items: flex-start; gap: 12px; }
.trial-local .hero-actions > .button { min-height: 52px; min-width: min(220px, 100%); max-width: 100%; }
.hero-secondary { display: flex; flex-wrap: wrap; gap: 4px 24px; }
.trial-details { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; color: var(--teal); font-size: .9375rem; text-underline-offset: .2em; }
.trial-retry { background: transparent; border: 0; font: inherit; text-decoration: underline; cursor: pointer; }
.trial-actions a:focus-visible, .trial-actions button:focus-visible, .local-learning-nav a:focus-visible, .trial-local .hero-actions a:focus-visible { outline: 3px solid var(--teal); outline-offset: 4px; }
.trial-course-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.trial-card.surface { min-width: 0; box-shadow: none; }
.trial-description { font-size: 1rem; line-height: 1.8; margin: 16px 0 12px; }
.trial-card .trial-description { min-height: 3.6em; }
.trial-note { font-size: .875rem; line-height: 1.8; color: var(--text-secondary); margin: 0 0 24px; }
.trial-actions { display: flex; flex-direction: column; gap: 8px; width: 100%; margin-top: auto; }
.trial-actions .button { width: 100%; min-height: 52px; margin: 0; }
.trial-entry.surface { padding: 28px; }
.trial-entry h2 { margin-bottom: 0; }
.trial-entry .trial-note { margin-bottom: 8px; }
.trial-entry .trial-scope { font-size: .9375rem; line-height: 1.8; max-width: 44em; margin: 0; }
.trial-entry .trial-actions { max-width: 24rem; margin-top: 24px; }
.course-content h3 { margin-top: 24px; }
.course-content li { margin: 8px 0; }
.course-content .trial-actions { max-width: 24rem; margin-top: 24px; }
.five-trial-start > .button { margin: 12px 0; }
.trial-total { font-size: 1.25rem; font-weight: 700; margin: 16px 0; }
@media (max-width: 1023px) {
  .home.trial-local { --trial-content-width: 680px; }
  .hero { grid-template-columns: minmax(0, 1fr); max-width: 680px; gap: 36px; padding-top: 36px; }
  .hero-title { font-size: 4.25rem; }
  .hero-tagline { font-size: 1.8125rem; }
  .hero::before { display: none; }
  .method-inner { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px 0; }
  .method-inner > h2 { grid-column: 1 / -1; white-space: normal; }
  .method-step { padding: 0 16px; }
  .home-courses-inner { padding: 36px 0 40px; }
}
@media (max-width: 639px) {
  .header-inner .local-learning-nav { width: 100%; flex-direction: column; align-items: stretch; gap: 4px; }
  .local-learning-nav .nav-link { justify-content: flex-start; }
  .trial-local .hero-secondary { flex-direction: column; align-items: flex-start; gap: 4px; width: 100%; }
  .home.trial-local { --trial-gutters: 32px; }
  .trial-local .hero-actions > .button { width: 100%; }
  .trial-card .trial-description { min-height: 0; }
  .trial-entry.surface { padding: 20px; }
  .header-inner { width: calc(100% - 32px); min-height: 72px; gap: 12px; flex-wrap: wrap; }
  .brand-mark { min-width: 30px; min-height: 30px; padding: 4px; font-size: 22px; }
  .brand-name { font-size: 1.125rem; }
  .header-inner nav { margin-left: auto; gap: 0 16px; }
  /* Course selection is never hidden behind a menu: wrap the row instead. */
  .header-inner nav .nav-link { font-size: .875rem; }
  .course-bar-inner { width: calc(100% - 32px); }
  .course-nav { gap: 0 16px; padding: 2px 0 4px; }
  .course-nav-name { width: 100%; min-height: 44px; padding-right: 0; border-right: 0; border-bottom: 1px solid var(--border-subtle); }
  .home-courses-inner { width: calc(100% - 32px); padding: 32px 0 36px; }
  .course-grid { grid-template-columns: minmax(0, 1fr); gap: 16px; }
  .course-card.surface { padding: 20px; }
  .hero { width: calc(100% - 32px); padding-top: 32px; padding-bottom: 36px; gap: 32px; }
  .hero-title { font-size: clamp(3rem, 15vw, 4.25rem); }
  .hero-tagline { font-size: 1.8125rem; letter-spacing: .015em; }
  .hero-lead { font-size: .9375rem; }
  .hero-actions { flex-direction: column; gap: 12px; }
  .hero-note { margin-top: 12px; }
  .experience-card { padding: 18px; box-shadow: none; }
  .experience-card::before { display: none; }
  .experience-head { align-items: flex-start; }
  .experience-head h2 { font-size: 1.125rem; }
  .experience-path li > div { display: block; }
  .experience-path h3 { margin-bottom: 4px; }
  .experience-question { display: block; padding: 16px; }
  .experience-return > div { display: block; }
  .experience-return h3 { margin-bottom: 4px; }
  .experience-question .step-number { position: static; display: block; margin-bottom: 8px; }
  .experience-return { padding: 12px; }
  .method-inner { width: calc(100% - 32px); grid-template-columns: repeat(2, minmax(0, 1fr)); padding: 26px 0 30px; gap: 24px 0; }
  .method-step { padding: 0 12px; }
  .footer-inner { width: calc(100% - 32px); padding: 24px 0; }
}

.course-nav-link[aria-current="page"] { color: var(--teal); text-decoration: underline; text-underline-offset: 5px; }

.article-site { background: var(--paper); color: var(--ink); font-family: var(--font-body); line-height: 1.9; }
.article-header { background: var(--white); border-bottom: 1px solid var(--border-subtle); }
.article-header-inner { max-width: 1180px; margin: auto; padding: 20px 24px; display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.article-header nav, .article-footer nav { display: flex; flex-wrap: wrap; gap: 12px 24px; font-size: .875rem; }
.article-header nav a { padding: 8px 0; }
.article-main { max-width: 820px; margin: 48px auto 80px; padding: 0 24px; }
.article-main h1 { font-size: clamp(1.7rem, 4.5vw, 2.5rem); line-height: 1.55; letter-spacing: .025em; }
.article-label { color: var(--teal); font-size: .875rem; font-weight: 700; }
.article-breadcrumb, .article-dates { font-size: .8125rem; color: var(--text-secondary); }
.article-intro { color: var(--text-secondary); }
.article-main:has(> .article-list) { max-width: 1040px; margin-top: 28px; }
.article-main:has(> .article-list) > .article-label { margin: 0 0 8px; }
.article-main:has(> .article-list) > h1 { margin: 0 0 8px; }
.article-main:has(> .article-list) > .article-intro { margin: 0 0 24px; }
.article-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); align-items: start; gap: 20px; list-style: none; padding: 0; margin: 0; }
.article-card { background: var(--white); border: 1px solid var(--border-subtle); border-radius: 12px 4px; padding: 18px; min-width: 0; overflow-wrap: anywhere; }
.article-card .article-label { font-size: .8125rem; line-height: 1.6; margin: 0 0 10px; }
.article-card h2 { font-size: 1.125rem; margin: 0 0 10px; line-height: 1.65; }
.article-card h2 a { display: block; min-height: 44px; }
.article-card h2 a:focus-visible { outline: 3px solid var(--teal); outline-offset: 4px; }
.article-card p:last-child { margin: 0; font-size: .9375rem; line-height: 1.8; display: -webkit-box; -webkit-box-orient: vertical; -webkit-line-clamp: 2; overflow: hidden; }
@media (max-width: 700px) { .article-list { grid-template-columns: minmax(0, 1fr); gap: 16px; }
  .article-main:has(> .article-list) { margin-top: 24px; }
}
.article-toc, .article-related { background: var(--mist); border-radius: 12px 4px; padding: 24px; margin: 32px 0; font-size: 1rem; }
.article-toc p { font-weight: 700; margin-bottom: 8px; }
.article-toc ol { padding-left: 1.5em; margin-bottom: 0; }
.article-body { font-size: 1.0625rem; line-height: 2; overflow-wrap: anywhere; }
.article-body h2 { font-size: 1.5rem; border-bottom: 2px solid var(--mist); padding-bottom: 12px; margin: 48px 0 24px; scroll-margin-top: 24px; }
.article-body h3 { margin-top: 32px; }
.article-body p, .article-body ul, .article-body ol { margin-bottom: 24px; }
.article-body ul, .article-body ol, .article-related ul { padding-left: 1.5em; }
.article-table { overflow-x: auto; max-width: 100%; margin: 24px 0; border: 1px solid var(--border-subtle); background: var(--white); }
.article-table table { width: 100%; min-width: 580px; border-collapse: collapse; font-size: .9375rem; line-height: 1.7; }
.article-table th, .article-table td { text-align: left; padding: 14px; border-bottom: 1px solid var(--border-subtle); vertical-align: top; }
.article-table th { background: var(--mist); }
.article-footer { max-width: 1180px; margin: auto; padding: 32px 24px; border-top: 1px solid var(--border-subtle); }
@media (max-width: 480px) { .article-header-inner { padding: 16px 20px; gap: 12px; } .article-main { padding: 0 20px; margin-top: 28px; } .article-card { padding: 18px; } .article-toc, .article-related { padding: 20px; } .article-body { font-size: 1rem; } .article-header .brand-name { font-size: 1.5rem; } }