:root {
  --ink: #17212a;
  --ink-soft: #526170;
  --ink-muted: #72808d;
  --page: #f7f9f7;
  --paper: #ffffff;
  --green: #2d6a4f;
  --green-soft: #e8f2ed;
  --blue: #2f75d6;
  --blue-soft: #eaf2fd;
  --gold: #b98218;
  --gold-soft: #fff6df;
  --line: rgba(23, 33, 42, 0.13);
  --line-strong: rgba(23, 33, 42, 0.22);
  --header-height: 72px;
  --container: min(1180px, calc(100vw - 40px));
  --content: 800px;
  --font-ui: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 26px);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--page);
  font-family: var(--font-ui);
  line-height: 1.7;
}

button,
input {
  font: inherit;
}

img,
svg {
  display: block;
}

img {
  max-width: 100%;
}

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

h1,
h2,
h3,
p {
  margin-top: 0;
}

kbd,
code {
  font-family: "Cascadia Mono", "SFMono-Regular", Consolas, monospace;
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 100;
  padding: 8px 12px;
  color: var(--ink);
  background: #fff;
  border: 1px solid var(--line);
  transform: translateY(-160%);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  min-height: var(--header-height);
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}

.header-inner,
.brand,
.header-actions,
.language-button,
.back-link,
.hero-facts,
.preview-head,
.footer-inner,
.footer-brand,
.site-footer nav {
  display: flex;
  align-items: center;
}

.header-inner {
  justify-content: space-between;
  width: var(--container);
  min-height: var(--header-height);
  margin: 0 auto;
}

.brand {
  gap: 10px;
  font-weight: 780;
}

.brand img {
  width: 38px;
  height: 38px;
}

.brand small {
  color: var(--ink-muted);
  font-size: 0.78rem;
  font-weight: 650;
}

.header-actions {
  gap: 16px;
}

.language-picker {
  position: relative;
}

.language-button {
  min-height: 40px;
  gap: 8px;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--ink-soft);
  background: #fff;
  cursor: pointer;
  font-size: 0.86rem;
  font-weight: 650;
  transition: color 160ms ease, border-color 160ms ease, background 160ms ease;
}

.language-button:hover,
.language-button[aria-expanded="true"] {
  color: var(--ink);
  border-color: var(--line-strong);
  background: #f2f5f3;
}

.language-button > img {
  width: 18px;
  height: 18px;
}

.language-button .chevron {
  transition: transform 160ms ease;
}

.language-button[aria-expanded="true"] .chevron {
  transform: rotate(180deg);
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 60;
  display: grid;
  width: 184px;
  padding: 6px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
  box-shadow: 0 18px 44px rgba(14, 24, 31, 0.16);
}

.language-menu[hidden] {
  display: none;
}

.language-menu button {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  min-height: 40px;
  padding: 8px 10px;
  border: 0;
  border-radius: 5px;
  color: var(--ink-soft);
  background: transparent;
  cursor: pointer;
  text-align: left;
}

.language-menu button:hover {
  color: var(--ink);
  background: var(--green-soft);
}

.menu-check {
  color: var(--green);
  opacity: 0;
}

.language-menu button[aria-checked="true"] {
  color: var(--ink);
  font-weight: 720;
}

.language-menu button[aria-checked="true"] .menu-check {
  opacity: 1;
}

.back-link {
  min-height: 40px;
  gap: 8px;
  color: var(--ink-soft);
  font-size: 0.9rem;
  font-weight: 680;
  transition: color 160ms ease;
}

.back-link:hover {
  color: var(--green);
}

.brand:focus-visible,
.back-link:focus-visible,
.language-button:focus-visible,
.language-menu button:focus-visible,
.docs-sidebar a:focus-visible,
.mobile-toc a:focus-visible,
.button:focus-visible,
.text-link:focus-visible,
.site-footer a:focus-visible,
.faq-list summary:focus-visible {
  outline: 3px solid rgba(47, 117, 214, 0.35);
  outline-offset: 3px;
}

.tutorial-hero {
  padding: 78px 0 72px;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 410px;
  align-items: center;
  gap: 86px;
  width: var(--container);
  margin: 0 auto;
}

.hero-copy {
  max-width: 690px;
}

.eyebrow,
.section-kicker {
  color: var(--green);
  font-size: 0.82rem;
  font-weight: 780;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 11px;
  margin-bottom: 19px;
}

.eyebrow::before {
  content: "";
  width: 30px;
  height: 2px;
  background: var(--green);
}

h1 {
  max-width: 680px;
  margin-bottom: 20px;
  font-size: 3.65rem;
  line-height: 1.12;
  letter-spacing: 0;
  text-wrap: balance;
}

.hero-lead {
  max-width: 650px;
  margin-bottom: 30px;
  color: var(--ink-soft);
  font-size: 1.08rem;
  line-height: 1.85;
}

.hero-facts {
  gap: 30px;
}

.hero-facts span {
  display: grid;
  min-width: 110px;
  gap: 2px;
}

.hero-facts b {
  color: var(--ink-muted);
  font-size: 0.72rem;
  font-weight: 680;
}

.hero-facts small {
  color: var(--ink);
  font-size: 0.87rem;
  font-weight: 700;
}

.formula-preview {
  position: relative;
  display: grid;
  min-height: 360px;
  align-content: start;
  justify-items: center;
  padding: 104px 38px 32px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f4f7f5;
  overflow: hidden;
}

.formula-preview::before {
  content: "";
  position: absolute;
  inset: 18px;
  border: 1px solid rgba(45, 106, 79, 0.14);
  pointer-events: none;
}

.preview-head {
  position: absolute;
  top: 34px;
  left: 36px;
  gap: 11px;
}

.preview-head img {
  width: 34px;
  height: 34px;
}

.preview-head div {
  display: grid;
  gap: 1px;
}

.preview-head strong {
  font-size: 0.85rem;
}

.preview-head span {
  color: var(--ink-muted);
  font-size: 0.7rem;
}

.formula-preview code {
  max-width: 100%;
  padding: 9px 11px;
  color: #36506b;
  background: var(--blue-soft);
  border: 1px solid rgba(47, 117, 214, 0.16);
  border-radius: 5px;
  font-size: 0.8rem;
  overflow-wrap: anywhere;
}

.preview-arrow {
  margin: 22px 0;
  color: var(--green);
  transform: rotate(90deg);
}

.rendered-formula {
  min-height: 50px;
  color: #111820;
  font-family: Cambria, "Times New Roman", serif;
  font-size: 2rem;
  white-space: nowrap;
}

.rendered-formula sup,
.rendered-formula sub {
  font-size: 0.55em;
}

.formula-preview > p {
  margin: 27px 0 0;
  color: var(--ink-muted);
  font-size: 0.75rem;
  text-align: center;
}

.content-width {
  width: var(--container);
  margin: 0 auto;
}

.quick-start {
  padding: 62px 0 66px;
  background: var(--green-soft);
  border-bottom: 1px solid rgba(45, 106, 79, 0.12);
}

.section-heading {
  max-width: 720px;
}

.section-kicker {
  margin-bottom: 9px;
}

.section-heading h2,
.support-section h2 {
  margin-bottom: 15px;
  font-size: 2rem;
  line-height: 1.3;
  letter-spacing: 0;
  text-wrap: balance;
}

.section-heading > p:last-child,
.support-section > div > p:last-child {
  color: var(--ink-soft);
  line-height: 1.85;
}

.quick-steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  margin: 36px 0 0;
  padding: 0;
  list-style: none;
}

.quick-steps li {
  min-height: 126px;
  padding: 0 28px;
  border-left: 1px solid rgba(45, 106, 79, 0.2);
}

.quick-steps li:first-child {
  padding-left: 0;
  border-left: 0;
}

.quick-steps li:last-child {
  padding-right: 0;
}

.quick-steps span {
  display: block;
  margin-bottom: 14px;
  color: var(--green);
  font-size: 0.76rem;
  font-weight: 800;
}

.quick-steps p {
  margin: 0;
  color: #33473d;
  font-size: 0.93rem;
  line-height: 1.75;
}

.mobile-toc {
  display: none;
}

.docs-layout {
  display: grid;
  grid-template-columns: 210px minmax(0, var(--content));
  justify-content: center;
  align-items: start;
  gap: 78px;
  width: var(--container);
  margin: 0 auto;
  padding: 84px 0 104px;
}

.docs-sidebar {
  position: sticky;
  top: calc(var(--header-height) + 28px);
}

.docs-sidebar > p {
  margin-bottom: 14px;
  color: var(--ink-muted);
  font-size: 0.72rem;
  font-weight: 750;
}

.docs-sidebar nav {
  display: grid;
  padding-left: 15px;
  border-left: 1px solid var(--line);
}

.docs-sidebar nav a {
  position: relative;
  padding: 7px 0;
  color: var(--ink-muted);
  font-size: 0.86rem;
  transition: color 160ms ease;
}

.docs-sidebar nav a::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: -16px;
  width: 2px;
  background: var(--green);
  opacity: 0;
}

.docs-sidebar nav a:hover,
.docs-sidebar nav a.is-active {
  color: var(--ink);
  font-weight: 680;
}

.docs-sidebar nav a.is-active::before {
  opacity: 1;
}

.sidebar-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 24px;
  color: var(--green);
  font-size: 0.84rem;
  font-weight: 720;
}

.tutorial-section {
  position: relative;
  padding: 0 0 88px;
  scroll-margin-top: calc(var(--header-height) + 28px);
}

.tutorial-section + .tutorial-section {
  padding-top: 84px;
  border-top: 1px solid var(--line);
}

.section-index {
  position: absolute;
  top: 4px;
  right: 0;
  color: rgba(23, 33, 42, 0.13);
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1;
}

.tutorial-section + .tutorial-section .section-index {
  top: 88px;
}

.procedure {
  display: grid;
  gap: 0;
  margin: 38px 0 0;
  padding: 0;
  list-style: none;
}

.procedure li {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 20px;
  min-height: 116px;
}

.procedure li > span {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  align-self: start;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  color: #fff;
  background: var(--green);
  font-size: 0.8rem;
  font-weight: 800;
}

.procedure li:not(:last-child) > span::after {
  content: "";
  position: absolute;
  top: 38px;
  left: 18px;
  width: 1px;
  height: 78px;
  background: rgba(45, 106, 79, 0.25);
}

.procedure h3 {
  margin-bottom: 7px;
  font-size: 1.02rem;
  line-height: 1.5;
}

.procedure p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.93rem;
}

.compact-procedure li {
  min-height: 102px;
}

.compact-procedure li:not(:last-child) > span::after {
  height: 64px;
}

.delimiter-guide {
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
  margin-top: 24px;
  padding: 18px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.delimiter-guide > div {
  display: flex;
  align-items: center;
  gap: 10px;
}

.delimiter-guide code {
  min-width: 72px;
  padding: 4px 8px;
  border: 1px solid rgba(47, 117, 214, 0.16);
  border-radius: 5px;
  color: #315471;
  background: var(--blue-soft);
  font-size: 0.83rem;
  text-align: center;
}

.delimiter-guide span {
  color: var(--ink-soft);
  font-size: 0.86rem;
}

.notice {
  display: grid;
  grid-template-columns: 22px minmax(0, 1fr);
  gap: 12px;
  margin-top: 28px;
  padding: 18px 20px;
  border: 1px solid transparent;
  border-radius: 6px;
}

.notice svg {
  margin-top: 3px;
}

.notice p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
}

.notice-info {
  color: #315471;
  background: var(--blue-soft);
  border-color: rgba(47, 117, 214, 0.13);
}

.notice-tip {
  color: #355845;
  background: var(--green-soft);
  border-color: rgba(45, 106, 79, 0.13);
}

.notice-warning {
  color: #765716;
  background: var(--gold-soft);
  border-color: rgba(185, 130, 24, 0.15);
}

.command-list {
  display: grid;
  margin-top: 36px;
  border-top: 1px solid var(--line);
}

.command-item {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 22px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.command-item > img {
  width: 42px;
  height: 42px;
  object-fit: contain;
}

.command-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.command-title h3 {
  margin-bottom: 9px;
  font-size: 1.14rem;
}

kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 28px;
  padding: 3px 8px;
  border: 1px solid var(--line-strong);
  border-bottom-width: 2px;
  border-radius: 5px;
  color: #34414c;
  background: #fff;
  font-size: 0.74rem;
  font-weight: 650;
  white-space: nowrap;
}

.command-item p {
  margin-bottom: 20px;
  color: var(--ink-soft);
  font-size: 0.93rem;
}

.document-example {
  min-height: 72px;
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: 5px;
  color: #3b4650;
  background: #fff;
  font-family: Cambria, "Times New Roman", serif;
  font-size: 1rem;
}

.inline-example b {
  margin: 0 6px;
  color: #111820;
  font-size: 1.15rem;
  font-weight: 500;
}

.display-example {
  display: grid;
  place-items: center;
}

.display-example b {
  color: #111820;
  font-size: 1.45rem;
  font-weight: 500;
}

.display-example sup,
.display-example sub {
  font-size: 0.6em;
}

.conversion-example {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr);
  align-items: center;
  gap: 18px;
  margin-top: 26px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
}

.conversion-example > div {
  display: grid;
  gap: 12px;
  min-width: 0;
}

.conversion-example span {
  color: var(--ink-muted);
  font-size: 0.7rem;
  font-weight: 700;
}

.conversion-example code {
  color: #315471;
  font-size: 0.86rem;
  overflow-wrap: anywhere;
}

.conversion-example strong {
  font-family: Cambria, "Times New Roman", serif;
  font-size: 1.35rem;
  font-weight: 500;
}

.conversion-example > svg {
  color: var(--green);
}

.edit-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 20px minmax(0, 1fr) 20px minmax(0, 1fr);
  align-items: center;
  gap: 13px;
  margin-top: 34px;
  padding: 28px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.edit-flow > div {
  display: grid;
  gap: 8px;
}

.edit-flow > div:last-of-type {
  grid-column: 5;
}

.edit-flow > div span {
  color: var(--green);
  font-size: 0.72rem;
  font-weight: 800;
}

.edit-flow strong {
  font-size: 0.9rem;
  line-height: 1.55;
}

.edit-flow > svg {
  color: var(--ink-muted);
}

.omath-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 110px minmax(0, 1fr);
  align-items: center;
  gap: 24px;
  margin-top: 34px;
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
}

.omath-flow > div:not(.two-way-arrow) {
  display: grid;
  justify-items: center;
  gap: 8px;
  min-height: 94px;
  align-content: center;
  background: #f4f7f5;
  border: 1px solid rgba(23, 33, 42, 0.08);
  border-radius: 5px;
}

.omath-flow span {
  color: var(--ink-muted);
  font-size: 0.72rem;
}

.omath-flow strong {
  font-size: 1rem;
}

.two-way-arrow {
  display: grid;
  justify-items: center;
  gap: 8px;
  color: var(--green);
}

.host-limit {
  margin: 22px 0 0;
  color: var(--ink-soft);
  font-size: 0.9rem;
}

.setting-list {
  display: grid;
  margin-top: 35px;
  border-top: 1px solid var(--line);
}

.setting-list article {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 18px;
  padding: 27px 0;
  border-bottom: 1px solid var(--line);
}

.setting-list article > span {
  color: var(--blue);
  font-size: 0.73rem;
  font-weight: 800;
}

.setting-list h3 {
  margin-bottom: 7px;
  font-size: 1.03rem;
}

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

.shortcut-table {
  margin-top: 34px;
  border-top: 1px solid var(--line);
}

.shortcut-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 190px;
  align-items: center;
  min-height: 59px;
  padding: 0 14px;
  border-bottom: 1px solid var(--line);
  font-size: 0.9rem;
}

.shortcut-row kbd {
  justify-self: start;
}

.shortcut-head {
  min-height: 46px;
  color: var(--ink-muted);
  background: #f0f3f1;
  font-size: 0.72rem;
  font-weight: 750;
}

.faq-list {
  margin-top: 30px;
  border-top: 1px solid var(--line);
}

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

.faq-list summary {
  position: relative;
  padding: 22px 42px 22px 0;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 680;
  list-style: none;
}

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

.faq-list summary::before,
.faq-list summary::after {
  content: "";
  position: absolute;
  top: 31px;
  right: 7px;
  width: 14px;
  height: 2px;
  background: var(--green);
}

.faq-list summary::after {
  transform: rotate(90deg);
  transition: transform 160ms ease;
}

.faq-list details[open] summary::after {
  transform: rotate(0deg);
}

.faq-list details p {
  max-width: 700px;
  margin: -6px 0 22px;
  color: var(--ink-soft);
  font-size: 0.92rem;
  line-height: 1.85;
}

.support-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 36px;
  padding: 42px;
  color: #fff;
  background: #17212a;
  border-radius: 8px;
}

.support-section .section-kicker {
  color: #8ebaff;
}

.support-section h2 {
  max-width: 510px;
}

.support-section > div > p:last-child {
  max-width: 560px;
  margin-bottom: 0;
  color: rgba(255, 255, 255, 0.67);
}

.support-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  min-width: 260px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 43px;
  padding: 9px 15px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 720;
}

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

.button-primary:hover {
  background: #245a42;
}

.button-secondary {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.26);
}

.button-secondary:hover {
  border-color: rgba(255, 255, 255, 0.55);
  background: rgba(255, 255, 255, 0.06);
}

.text-link {
  grid-column: 1 / -1;
  justify-self: end;
  color: rgba(255, 255, 255, 0.66);
  font-size: 0.8rem;
}

.text-link:hover {
  color: #fff;
}

.site-footer {
  padding: 28px 0;
  color: rgba(255, 255, 255, 0.63);
  background: #111920;
  font-size: 0.8rem;
}

.footer-inner {
  justify-content: space-between;
  gap: 24px;
  width: var(--container);
  margin: 0 auto;
}

.footer-brand {
  gap: 9px;
  color: #fff;
  font-weight: 720;
}

.footer-brand img {
  width: 34px;
  height: 34px;
}

.site-footer nav {
  gap: 20px;
}

.site-footer a {
  color: rgba(255, 255, 255, 0.76);
}

.site-footer a:hover {
  color: #fff;
}

html[lang="en"] h1 {
  font-size: 3.35rem;
}

@media (max-width: 1040px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr) 350px;
    gap: 48px;
  }

  h1 {
    font-size: 3rem;
  }

  html[lang="en"] h1 {
    font-size: 2.8rem;
  }

  .docs-layout {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 46px;
  }

  .support-section {
    grid-template-columns: 1fr;
    align-items: start;
  }

  .support-actions {
    width: min(100%, 360px);
  }

  .text-link {
    justify-self: start;
  }
}

@media (max-width: 820px) {
  .tutorial-hero {
    padding-top: 62px;
  }

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

  .hero-copy {
    max-width: 720px;
  }

  .formula-preview {
    min-height: 310px;
  }

  .quick-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    row-gap: 30px;
  }

  .quick-steps li:nth-child(3) {
    padding-left: 0;
    border-left: 0;
  }

  .docs-layout {
    display: block;
    padding-top: 54px;
  }

  .docs-sidebar {
    display: none;
  }

  .mobile-toc {
    display: block;
    width: var(--container);
    margin: 34px auto 0;
    border: 1px solid var(--line);
    border-radius: 6px;
    background: #fff;
  }

  .mobile-toc summary {
    padding: 13px 16px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 720;
  }

  .mobile-toc nav {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1px;
    padding: 5px 12px 14px;
  }

  .mobile-toc a {
    padding: 7px 4px;
    color: var(--ink-soft);
    font-size: 0.82rem;
  }

  .edit-flow {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .edit-flow > div:last-of-type {
    grid-column: auto;
  }

  .edit-flow > svg {
    transform: rotate(90deg);
  }
}

@media (max-width: 620px) {
  :root {
    --container: calc(100vw - 30px);
    --header-height: 66px;
  }

  .header-inner {
    min-height: var(--header-height);
  }

  .brand small,
  .back-link span,
  .language-button > span,
  .language-button .chevron {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
  }

  .brand {
    gap: 8px;
  }

  .brand img {
    width: 34px;
    height: 34px;
  }

  .header-actions {
    gap: 8px;
  }

  .language-button,
  .back-link {
    justify-content: center;
    width: 40px;
    padding: 0;
  }

  .tutorial-hero {
    padding: 50px 0 48px;
  }

  .hero-inner {
    gap: 40px;
  }

  h1,
  html[lang="en"] h1 {
    font-size: 2.35rem;
    line-height: 1.17;
  }

  .hero-lead {
    font-size: 1rem;
  }

  .hero-facts {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px 22px;
  }

  .formula-preview {
    min-height: 290px;
    padding: 90px 22px 28px;
  }

  .formula-preview::before {
    inset: 12px;
  }

  .preview-head {
    top: 25px;
    left: 25px;
  }

  .rendered-formula {
    font-size: 1.72rem;
  }

  .quick-start {
    padding: 48px 0;
  }

  .section-heading h2,
  .support-section h2 {
    font-size: 1.65rem;
  }

  .quick-steps {
    grid-template-columns: 1fr;
    row-gap: 0;
  }

  .quick-steps li,
  .quick-steps li:first-child,
  .quick-steps li:nth-child(3),
  .quick-steps li:last-child {
    min-height: 0;
    padding: 22px 0;
    border-left: 0;
    border-top: 1px solid rgba(45, 106, 79, 0.18);
  }

  .mobile-toc nav {
    grid-template-columns: 1fr;
  }

  .docs-layout {
    padding: 48px 0 76px;
  }

  .tutorial-section {
    padding-bottom: 62px;
  }

  .tutorial-section + .tutorial-section {
    padding-top: 62px;
  }

  .section-index {
    display: none;
  }

  .procedure li {
    grid-template-columns: 36px minmax(0, 1fr);
    gap: 15px;
  }

  .procedure li > span {
    width: 34px;
    height: 34px;
  }

  .procedure li:not(:last-child) > span::after {
    top: 34px;
    left: 16px;
  }

  .command-item {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 15px;
  }

  .command-item > img {
    width: 36px;
    height: 36px;
  }

  .command-title {
    align-items: flex-start;
    flex-direction: column;
    gap: 0;
    margin-bottom: 14px;
  }

  .command-title h3 {
    margin-bottom: 7px;
  }

  .document-example {
    margin-left: -55px;
  }

  .conversion-example {
    grid-template-columns: 1fr;
    padding: 22px;
  }

  .delimiter-guide {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }

  .conversion-example > svg {
    transform: rotate(90deg);
  }

  .omath-flow {
    grid-template-columns: 1fr;
    padding: 22px;
  }

  .two-way-arrow svg {
    transform: rotate(90deg);
  }

  .shortcut-row {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 12px;
    padding-inline: 8px;
  }

  .support-section {
    padding: 30px 24px;
  }

  .support-actions {
    grid-template-columns: 1fr;
    min-width: 0;
    width: 100%;
  }

  .text-link {
    grid-column: auto;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 380px) {
  :root {
    --container: calc(100vw - 22px);
  }

  h1,
  html[lang="en"] h1 {
    font-size: 2.08rem;
  }

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

  .formula-preview code {
    font-size: 0.72rem;
  }

  .shortcut-row {
    font-size: 0.82rem;
  }

  .shortcut-row kbd {
    font-size: 0.66rem;
  }
}

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

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