:root {
  --ob-ink: #12161c;
  --ob-paper: #f7f7f5;
  --ob-white: #ffffff;
  --ob-soft: #eff0ed;
  --ob-tab: #e7e9e5;
  --ob-border: #dfe2dd;
  --ob-muted: #5b6470;
  --ob-muted-light: #c9cdd3;
  --ob-green: #0f7b4f;
  --ob-green-dark: #0b5c3b;
  --ob-gold: #e8b33c;
  --ob-dark-border: #2b3038;
  --ob-container: 1180px;
  --ob-gutter: clamp(18px, 3vw, 24px);
  --ob-rail: 44px;
  --ob-gap: 24px;
  --ob-heading: "Arial Narrow", Arial, sans-serif;
  --ob-body: "Segoe UI", Arial, sans-serif;
  --ob-mono: Consolas, "Courier New", monospace;
  --ob-focus: 3px solid var(--ob-gold);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--ob-paper);
  color: var(--ob-ink);
  font-family: var(--ob-body);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.menu-open {
  overflow: hidden;
}

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

a {
  color: var(--ob-green);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--ob-green-dark);
}

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

:focus-visible {
  outline: var(--ob-focus);
  outline-offset: 3px;
}

h1,
h2,
h3,
h4 {
  font-family: var(--ob-heading);
  letter-spacing: -0.025em;
  line-height: 1.12;
  text-wrap: balance;
}

h2 {
  margin: 0;
  font-size: clamp(1.8rem, 3vw, 2.3rem);
}

p {
  text-wrap: pretty;
}

.skip-link {
  position: fixed;
  z-index: 999;
  top: 12px;
  left: 12px;
  transform: translateY(-150%);
  padding: 12px 16px;
  background: var(--ob-ink);
  color: var(--ob-white);
  font-weight: 700;
}

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

.site-header {
  position: relative;
  z-index: 50;
  border-bottom: 1px solid var(--ob-border);
  background: var(--ob-soft);
}

.site-header__inner {
  max-width: var(--ob-container);
  margin: 0 auto;
  padding: 14px var(--ob-gutter) 0;
}

.site-brand-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 24px;
  padding-bottom: 14px;
}

.site-brand {
  display: flex;
  flex-direction: column;
  gap: 4px;
  color: var(--ob-ink);
  text-decoration: none;
}

.site-brand:hover {
  color: var(--ob-ink);
  text-decoration: none;
}

.site-brand__name {
  font-family: var(--ob-heading);
  font-size: clamp(1.7rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
}

.site-brand__tagline,
.site-location,
.eyebrow {
  margin: 0;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.7rem;
  letter-spacing: 0.09em;
  line-height: 1.45;
  text-transform: uppercase;
}

.site-location {
  font-size: 0.72rem;
}

.site-nav {
  display: flex;
  align-items: flex-end;
  gap: 12px;
}

.site-nav__list {
  display: flex;
  flex: 1;
  align-items: flex-end;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav__list a {
  display: flex;
  min-height: 46px;
  align-items: center;
  padding: 10px 16px;
  border: 1px solid var(--ob-border);
  border-bottom: 0;
  border-radius: 3px 3px 0 0;
  background: var(--ob-tab);
  color: var(--ob-muted);
  font-size: 0.9rem;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 180ms ease, color 180ms ease, border-color 180ms ease;
}

.site-nav__list a:hover,
.site-nav__list .current-menu-item > a,
.home .site-nav__list li:first-child > a {
  border-top-color: var(--ob-gold);
  background: var(--ob-paper);
  color: var(--ob-ink);
}

.site-nav__external {
  display: flex;
  margin-left: auto;
}

.site-nav__external a {
  display: flex;
  min-height: 44px;
  align-items: center;
  padding: 10px;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  text-decoration: none;
  white-space: nowrap;
}

.menu-toggle {
  display: none;
  min-width: 48px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border: 1px solid var(--ob-border);
  border-radius: 3px;
  background: var(--ob-paper);
  cursor: pointer;
  font-weight: 700;
}

.menu-toggle__icon,
.menu-toggle__icon::before,
.menu-toggle__icon::after {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  content: "";
  transition: transform 180ms ease, opacity 180ms ease;
}

.menu-toggle__icon {
  position: relative;
}

.menu-toggle__icon::before {
  position: absolute;
  top: -6px;
}

.menu-toggle__icon::after {
  position: absolute;
  top: 6px;
}

.menu-toggle[aria-expanded="true"] .menu-toggle__icon {
  background: transparent;
}

.menu-toggle[aria-expanded="true"] .menu-toggle__icon::before {
  top: 0;
  transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .menu-toggle__icon::after {
  top: 0;
  transform: rotate(-45deg);
}

.sheet-columns {
  border-bottom: 1px solid var(--ob-border);
  background: var(--ob-paper);
}

.sheet-columns__inner {
  display: grid;
  max-width: var(--ob-container);
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--ob-gap);
  margin: 0 auto;
  padding: 5px var(--ob-gutter) 5px calc(var(--ob-gutter) + var(--ob-rail) + var(--ob-gap));
}

.sheet-columns span {
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.65rem;
  opacity: 0.42;
}

.site-main {
  overflow: clip;
}

.sheet-section {
  max-width: var(--ob-container);
  margin: 0 auto;
  padding: 0 var(--ob-gutter);
}

.sheet-section--dark {
  max-width: none;
  background: var(--ob-ink);
  color: var(--ob-paper);
}

.sheet-section--dark .sheet-section__row {
  max-width: calc(var(--ob-container) - (2 * var(--ob-gutter)));
  margin: 0 auto;
}

.sheet-section--bordered {
  border-top: 1px solid var(--ob-border);
}

.sheet-section__row {
  display: grid;
  grid-template-columns: var(--ob-rail) minmax(0, 1fr);
  gap: var(--ob-gap);
}

.sheet-row-number {
  padding-top: 78px;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.72rem;
}

.section-space {
  padding: clamp(62px, 8vw, 84px) 0;
}

.section-space--topless {
  padding-top: 0;
}

.hero-section__content {
  padding: 56px 0 64px;
}

.formula-bar {
  display: flex;
  overflow: hidden;
  max-width: 820px;
  min-height: 43px;
  border: 1px solid var(--ob-border);
  border-radius: 2px;
  background: var(--ob-white);
  font-family: var(--ob-mono);
  font-size: 0.78rem;
}

.formula-bar__cell,
.formula-bar__fx {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  border-right: 1px solid var(--ob-border);
}

.formula-bar__cell {
  width: 64px;
}

.formula-bar__fx {
  width: 44px;
  color: var(--ob-muted);
  font-style: italic;
}

.formula-bar__formula {
  display: block;
  overflow: hidden;
  padding: 10px 14px;
  color: var(--ob-ink);
  font-family: inherit;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.formula-bar__formula.is-typing::after {
  display: inline-block;
  width: 7px;
  height: 14px;
  margin-left: 2px;
  background: var(--ob-ink);
  content: "";
  transform: translateY(2px);
  animation: ob-caret 900ms steps(1) infinite;
}

@keyframes ob-caret {
  50% { opacity: 0; }
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: clamp(30px, 5vw, 52px);
  align-items: start;
  margin-top: 36px;
}

.selected-cell {
  position: relative;
  display: inline-block;
  max-width: 900px;
  margin-top: 16px;
  padding: clamp(19px, 3vw, 28px);
  border: 2px solid var(--ob-green);
  border-radius: 2px;
}

.selected-cell::after {
  position: absolute;
  right: -5px;
  bottom: -5px;
  width: 9px;
  height: 9px;
  background: var(--ob-green);
  content: "";
}

.selected-cell h1 {
  margin: 0;
  font-size: clamp(2.25rem, 5vw, 3.75rem);
  font-weight: 800;
  line-height: 1.03;
}

.hero-lead {
  max-width: 650px;
  margin: 28px 0 0;
  font-size: clamp(1.05rem, 2vw, 1.15rem);
  line-height: 1.65;
}

.profile-card {
  overflow: hidden;
  border: 1px solid var(--ob-border);
  border-radius: 2px;
  background: var(--ob-white);
}

.profile-card__image {
  width: 100%;
  height: 300px;
  object-fit: cover;
  object-position: 52% center;
}

.profile-card__body {
  padding: 16px 18px;
  border-top: 1px solid var(--ob-border);
}

.profile-card__body strong {
  display: block;
  font-family: var(--ob-heading);
  font-size: 1.35rem;
  line-height: 1.15;
}

.profile-card__body span {
  display: block;
  margin-top: 7px;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.68rem;
  letter-spacing: 0.07em;
  line-height: 1.55;
  text-transform: uppercase;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 24px;
  align-items: center;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 4px;
  font-weight: 700;
  text-align: center;
  text-decoration: none;
  transition: background-color 180ms ease, color 180ms ease;
}

.button--primary {
  background: var(--ob-green);
  color: var(--ob-white);
}

.button--primary:hover {
  background: var(--ob-green-dark);
  color: var(--ob-white);
}

.text-link,
.contact-link {
  padding: 10px 0;
  border-bottom: 1px solid var(--ob-border);
  color: var(--ob-ink);
  font-weight: 650;
  text-decoration: none;
}

.text-link:hover,
.contact-link:hover {
  border-bottom-color: var(--ob-green);
  color: var(--ob-green);
}

.text-link--large {
  display: inline-flex;
  margin-top: 26px;
  font-size: 1.05rem;
}

.proof-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 28px;
  margin: 48px 0 0;
  padding: 14px 0;
  border-top: 1px solid var(--ob-border);
  border-bottom: 1px solid var(--ob-border);
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  list-style: none;
  text-transform: uppercase;
}

.proof-strip li:not(:last-child)::after {
  margin-left: 28px;
  content: "·";
  opacity: 0.45;
}

.display-title {
  max-width: 760px;
  font-size: clamp(2rem, 4vw, 3.3rem);
}

.display-title--small {
  font-size: clamp(2rem, 3.4vw, 2.75rem);
}

.section-lead {
  max-width: 700px;
  margin: 24px 0 0;
  color: var(--ob-muted-light);
  font-size: 1.12rem;
  line-height: 1.65;
}

.section-lead--ink {
  color: var(--ob-ink);
}

.transformation-list {
  display: grid;
  gap: 12px;
  max-width: 940px;
  margin-top: 44px;
}

.transformation {
  display: grid;
  grid-template-columns: 1fr 44px 1fr;
  align-items: stretch;
}

.transformation > span:first-child,
.transformation strong {
  padding: 18px 20px;
  border: 1px solid var(--ob-dark-border);
  border-radius: 2px;
  font-size: 1rem;
  font-weight: 400;
}

.transformation > span:nth-child(2) {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
}

.transformation strong {
  border-color: var(--ob-gold);
  color: var(--ob-paper);
}

.thesis-result {
  max-width: 720px;
  margin: 36px 0 0;
  font-size: 1.2rem;
}

.method-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: 36px;
  border-top: 1px solid var(--ob-border);
  border-left: 1px solid var(--ob-border);
}

.method-grid article {
  padding: 24px;
  border-right: 1px solid var(--ob-border);
  border-bottom: 1px solid var(--ob-border);
}

.method-grid article > span,
.program-card > span,
.case-grid article > span,
.asset-note {
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.7rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.method-grid h3 {
  margin: 10px 0 8px;
  font-size: 1.2rem;
}

.method-grid p {
  margin: 0;
  color: var(--ob-muted);
  font-size: 0.95rem;
}

.program-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 32px;
}

.program-card {
  display: flex;
  min-height: 285px;
  flex-direction: column;
  padding: 26px;
  border: 1px solid var(--ob-border);
  border-radius: 2px;
  background: var(--ob-white);
  color: var(--ob-ink);
  text-decoration: none;
  transition: border-color 180ms ease, box-shadow 180ms ease;
}

.program-card:hover {
  border-color: var(--ob-green);
  box-shadow: 0 10px 24px rgb(18 22 28 / 7%);
  color: var(--ob-ink);
}

.program-card h3 {
  margin: 12px 0 10px;
  font-size: clamp(1.4rem, 2.4vw, 1.7rem);
}

.program-card p {
  margin: 0 0 24px;
  color: var(--ob-muted);
  font-size: 0.96rem;
}

.program-card strong {
  margin-top: auto;
  color: var(--ob-green);
  font-size: 0.9rem;
}

.reference-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 32px 0 0;
  padding: 0;
  border-top: 1px solid var(--ob-border);
  border-left: 1px solid var(--ob-border);
  list-style: none;
}

.reference-grid li {
  padding: 16px 18px;
  border-right: 1px solid var(--ob-border);
  border-bottom: 1px solid var(--ob-border);
  font-family: var(--ob-mono);
  font-size: 0.78rem;
}

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 32px;
}

.case-grid article {
  padding: 24px;
  border: 1px solid var(--ob-border);
  border-radius: 2px;
  background: var(--ob-white);
}

.case-grid h3 {
  margin: 0 0 8px;
  font-size: 1.2rem;
}

.case-grid h3 a {
  color: inherit;
  text-decoration: none;
}

.case-grid h3 a:hover {
  color: var(--ob-green);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.case-grid p {
  margin: 14px 0 0;
  color: var(--ob-muted);
  font-size: 0.95rem;
}

.asset-note {
  margin: 18px 0 0;
}

.trainer-grid {
  display: grid;
  grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}

.trainer-photo {
  margin: 0;
  padding: 8px;
  border: 1px solid var(--ob-border);
  background: var(--ob-white);
}

.trainer-photo img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: center;
}

.trainer-photo figcaption {
  margin-top: 8px;
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.65rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.book-row {
  display: flex;
  gap: 24px;
  align-items: center;
  margin-top: 28px;
}

.book-row__cover {
  width: 112px;
  height: 146px;
  padding: 5px;
  border: 1px solid var(--ob-border);
  background: var(--ob-white);
  object-fit: contain;
}

.book-row ul {
  display: grid;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.book-row a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  font-weight: 700;
}

.faq-list {
  max-width: 880px;
  margin-top: 36px;
  border-top: 1px solid var(--ob-border);
}

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

.faq-list summary {
  position: relative;
  min-height: 66px;
  padding: 22px 52px 22px 0;
  cursor: pointer;
  font-family: var(--ob-heading);
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.3;
  list-style: none;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  position: absolute;
  top: 50%;
  right: 12px;
  width: 28px;
  height: 28px;
  color: var(--ob-green);
  content: "+";
  font-family: var(--ob-mono);
  font-size: 1.3rem;
  font-weight: 400;
  line-height: 28px;
  text-align: center;
  transform: translateY(-50%);
}

.faq-list details[open] summary::after {
  content: "−";
}

.faq-list details p {
  max-width: 760px;
  margin: -4px 0 24px;
  font-size: 1rem;
  line-height: 1.7;
}

.cta-section {
  max-width: none;
  border-top: 1px solid var(--ob-border);
  background: var(--ob-soft);
}

.cta-section .sheet-section__row {
  max-width: calc(var(--ob-container) - (2 * var(--ob-gutter)));
  margin: 0 auto;
}

.site-footer {
  background: var(--ob-ink);
  color: var(--ob-muted-light);
}

.site-footer__inner {
  max-width: var(--ob-container);
  margin: 0 auto;
  padding: 56px var(--ob-gutter) 38px;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 32px;
}

.footer-grid h2 {
  margin: 0 0 12px;
  color: #9ba3ae;
  font-family: var(--ob-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.footer-grid ul {
  display: grid;
  gap: 5px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-grid a,
.footer-grid li {
  color: var(--ob-muted-light);
  font-size: 0.94rem;
}

.footer-grid a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  text-decoration: none;
}

.footer-grid a:hover {
  color: var(--ob-white);
  text-decoration: underline;
}

.site-footer__copyright {
  margin: 40px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--ob-dark-border);
  color: #9ba3ae;
  font-family: var(--ob-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

/* Content and archive templates. */
.content-shell {
  max-width: var(--ob-container);
  margin: 0 auto;
  padding: clamp(52px, 8vw, 90px) var(--ob-gutter);
}

.content-shell--narrow {
  max-width: 860px;
}

.archive-header,
.entry-header {
  max-width: 880px;
  margin-bottom: 42px;
}

.archive-kicker,
.entry-meta {
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.archive-title,
.entry-title {
  margin: 10px 0 0;
  font-size: clamp(2.2rem, 5vw, 4rem);
}

.archive-summary {
  max-width: 760px;
  margin: 20px 0 0;
  font-size: 1.08rem;
  line-height: 1.7;
}

.archive-author {
  max-width: 760px;
  margin: 18px 0 0;
  color: var(--ob-muted);
  line-height: 1.65;
}

.archive-author a,
.archive-links a {
  color: var(--ob-ink);
  font-weight: 700;
  text-underline-offset: 3px;
}

.archive-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin-top: 22px;
}

.archive-links a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
}

.entry-title a {
  color: inherit;
  text-decoration: none;
}

.post-list {
  border-top: 1px solid var(--ob-border);
}

.post-list__item {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 28px;
  padding: 28px 0;
  border-bottom: 1px solid var(--ob-border);
}

.post-list__date {
  color: var(--ob-muted);
  font-family: var(--ob-mono);
  font-size: 0.75rem;
}

.post-list__item h2 {
  margin: 0;
  font-size: clamp(1.35rem, 2.6vw, 2rem);
}

.post-list__item h2 a {
  color: var(--ob-ink);
  text-decoration: none;
}

.post-list__item h2 a:hover {
  color: var(--ob-green);
}

.post-list__item p {
  max-width: 760px;
  margin: 10px 0 0;
  color: var(--ob-muted);
}

.pagination,
.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 38px;
}

.page-numbers {
  display: inline-flex;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 8px 13px;
  border: 1px solid var(--ob-border);
  background: var(--ob-white);
  color: var(--ob-ink);
  text-decoration: none;
}

.page-numbers.current,
.page-numbers:hover {
  border-color: var(--ob-green);
  color: var(--ob-green);
}

.entry-featured {
  margin: 36px 0;
}

.entry-featured img {
  width: 100%;
  max-height: 640px;
  object-fit: cover;
}

.entry-content {
  font-size: 1.08rem;
  line-height: 1.75;
}

.entry-content > * {
  max-width: 760px;
  margin-right: auto;
  margin-left: auto;
}

.entry-content > .alignwide {
  max-width: 1132px;
}

.entry-content > .alignfull {
  max-width: none;
}

.entry-content h2,
.entry-content h3 {
  margin-top: 1.9em;
  margin-bottom: 0.65em;
}

.entry-content a {
  overflow-wrap: anywhere;
}

.entry-content pre,
.entry-content table {
  overflow-x: auto;
}

.entry-content blockquote {
  padding: 6px 0 6px 24px;
  border-left: 3px solid var(--ob-green);
  color: var(--ob-muted);
}

.post-navigation {
  margin-top: 56px;
  padding-top: 24px;
  border-top: 1px solid var(--ob-border);
}

.post-navigation .nav-links {
  justify-content: space-between;
}

.post-navigation a {
  display: block;
  max-width: 360px;
  color: var(--ob-ink);
  font-weight: 700;
  text-decoration: none;
}

.empty-state {
  max-width: 680px;
  padding: 32px;
  border: 1px solid var(--ob-border);
  background: var(--ob-white);
}

.screen-reader-text {
  position: absolute !important;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(1px, 1px, 1px, 1px);
  white-space: nowrap;
}

@media (max-width: 980px) {
  .menu-toggle {
    display: inline-flex;
  }

  .site-location {
    margin-left: auto;
  }

  .site-nav {
    position: fixed;
    z-index: 45;
    inset: 84px 0 0;
    display: none;
    align-items: stretch;
    overflow-y: auto;
    padding: 24px;
    background: var(--ob-paper);
  }

  .site-nav.is-open {
    display: block;
  }

  .site-nav__list,
  .site-nav__external {
    display: grid;
    gap: 6px;
  }

  .site-nav__list a {
    min-height: 52px;
    border: 1px solid var(--ob-border);
    border-radius: 2px;
    background: var(--ob-white);
    font-size: 1rem;
  }

  .site-nav__external {
    grid-template-columns: 1fr 1fr;
    margin-top: 18px;
  }

  .site-nav__external a {
    min-height: 52px;
    justify-content: center;
    border: 1px solid var(--ob-border);
    background: var(--ob-soft);
  }

  .method-grid,
  .reference-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 820px) {
  :root {
    --ob-rail: 0px;
    --ob-gap: 0px;
  }

  .sheet-columns,
  .sheet-row-number {
    display: none;
  }

  .sheet-section__row {
    display: block;
  }

  .hero-grid,
  .trainer-grid {
    grid-template-columns: 1fr;
  }

  .profile-card {
    max-width: 360px;
  }

  .case-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 620px) {
  body {
    font-size: 16px;
  }

  .site-brand-row {
    align-items: center;
  }

  .site-brand__tagline {
    max-width: 210px;
  }

  .site-location {
    display: none;
  }

  .menu-toggle__label {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
  }

  .site-nav {
    top: 78px;
  }

  .hero-section__content {
    padding-top: 34px;
  }

  .formula-bar__cell {
    width: 48px;
  }

  .formula-bar__fx {
    width: 38px;
  }

  .selected-cell {
    padding: 18px;
  }

  .selected-cell h1 {
    font-size: clamp(2rem, 10.5vw, 3rem);
  }

  .button-row > * {
    width: 100%;
  }

  .text-link,
  .contact-link {
    min-height: 44px;
  }

  .proof-strip {
    display: grid;
    gap: 7px;
  }

  .proof-strip li::after {
    display: none;
  }

  .transformation {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .transformation > span:nth-child(2) {
    min-height: 30px;
    transform: rotate(90deg);
  }

  .method-grid,
  .program-grid,
  .reference-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .program-card {
    min-height: 0;
  }

  .book-row {
    align-items: flex-start;
  }

  .post-list__item {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

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