/* ─── Chinese text inline ─── */
.chinese-text {
  font-weight: 700;
}

/* ─── 404 Error page ─── */
.error-page {
  text-align: center;
  padding: 20px 24px 120px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.error-page__title {
  font-family: var(--font-heading);
  font-size: 200px;
  font-weight: 700;
  letter-spacing: -20px;
  line-height: 1;
  color: var(--color-heading);
  margin-bottom: 24px;
}

.error-page__message {
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 500;
  letter-spacing: -0.7px;
  color: #888;
  max-width: 600px;
  line-height: 1.6;
  margin-bottom: 32px;
}

/* ─── Hero sections ─── */
.hero {
  display: flex;
  align-items: center;
  gap: var(--space-12);
  padding: 0 0 var(--space-16);
}

.hero__image {
  flex-shrink: 0;
}

.hero__image img {
  max-width: 360px;
  width: 100%;
  height: auto;
}

.hero__content {
  flex: 1;
}

.hero__title {
  font-family: var(--font-heading);
  font-size: 62px;
  font-weight: 700;
  letter-spacing: -3.8px;
  margin-bottom: var(--space-6);
}

.hero__subtitle {
  font-size: var(--text-xl);
  color: var(--color-text-light);
  max-width: 600px;
  margin-bottom: var(--space-8);
  line-height: 1.6;
}

.hero__actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

@media (max-width: 809px) {
  .hero {
    flex-direction: column;
    text-align: center;
    padding: var(--space-4) 0 var(--space-8);
  }

  .hero__image img {
    max-width: 280px;
  }

  .hero__title {
    font-size: var(--text-3xl);
  }

  .hero__subtitle {
    font-size: var(--text-base);
  }

  .hero__actions {
    justify-content: center;
  }
}

@media (min-width: 810px) and (max-width: 1199px) {
  .hero__title {
    font-size: var(--text-5xl);
  }

  .hero__image img {
    max-width: 300px;
  }
}

/* ─── Legal pages ─── */
.legal-content {
  max-width: var(--container-narrow);
  margin: 0 auto;
  padding: 0 0 var(--space-12);
}

.legal-content h1 {
  margin-bottom: var(--space-8);
}

.legal-content h2 {
  margin-top: var(--space-8);
  margin-bottom: var(--space-4);
}

.legal-content p {
  margin-bottom: 1em;
  line-height: 1.7;
  text-align: justify;
}

.legal-content ul {
  list-style-type: disc;
  padding-left: 1.5em;
  margin-bottom: 1em;
}

.legal-content li {
  margin-bottom: 0.5em;
}

/* ─── Content sections (marketing pages) ─── */
.content-section {
  margin-bottom: var(--space-12);
}

.content-section h2 {
  margin-bottom: var(--space-6);
}

.content-section h3 {
  margin-top: var(--space-8);
  margin-bottom: var(--space-4);
}

.content-section .katex-display {
  margin: var(--space-8) 0;
}

.content-section p {
  margin-bottom: 1em;
  line-height: 1.8;
  text-align: justify;
}

.content-section p:last-child {
  margin-bottom: 0;
}

.content-list {
  list-style: disc;
  padding-left: 2.25em;
  margin-bottom: 1em;
}

.content-list li {
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border-light);
  line-height: 1.7;
}

.content-list li:last-child {
  border-bottom: none;
}

/* ─── Math tables ─── */
.math-table {
  overflow-x: auto;
  margin: var(--space-6) 0;
}

.math-table table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.math-table th,
.math-table td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border-light);
  text-align: left;
}

.math-table th {
  font-weight: 600;
  color: var(--color-heading);
  border-bottom-color: var(--color-border);
}

.math-table tr:last-child td {
  border-bottom: none;
}

/* ─── Page titles ─── */
.page-title {
  font-size: 50px;
  font-weight: 700;
  text-align: center;
  padding-top: var(--space-12);
  margin-bottom: var(--space-10);
}

.page-intro {
  font-size: var(--text-xl);
  color: var(--color-text-light);
  text-align: center;
  max-width: 700px;
  margin: 0 auto var(--space-12);
  line-height: 1.6;
}

@media (max-width: 809px) {
  .page-title {
    font-size: 32px;
  }
}

/* ─── Homepage feature blocks ─── */
.features-overview__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-10);
}

.feature-block {
  padding: var(--space-8);
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-light);
}

.feature-block__title {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-heading);
  margin-bottom: var(--space-4);
}

.feature-block__desc {
  font-size: var(--text-base);
  color: var(--color-text);
  line-height: 1.7;
  margin-bottom: var(--space-6);
}

.feature-block__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.feature-block__links a {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: 600;
  font-style: normal;
  color: var(--color-accent);
  padding: 4px 12px;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-full);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.feature-block__links a:hover {
  background-color: var(--color-accent);
  color: var(--color-white);
  text-decoration: none;
}

@media (max-width: 809px) {
  .features-overview__grid {
    grid-template-columns: 1fr;
  }

  .feature-block {
    padding: var(--space-6);
  }
}

/* ─── Features listing page ─── */
.feature-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.feature-list__item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-4);
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-border-light);
  color: var(--color-text);
  font-style: normal;
  font-weight: normal;
  transition: color var(--transition-fast);
}

.feature-list__item:first-child {
  border-top: 1px solid var(--color-border-light);
}

.feature-list__item:hover {
  color: var(--color-accent);
  text-decoration: none;
}

.feature-list__item strong {
  font-weight: 600;
  color: var(--color-heading);
  white-space: nowrap;
}

.feature-list__item:hover strong {
  color: var(--color-accent);
}

.feature-list__item span {
  font-size: var(--text-sm);
  color: var(--color-text-light);
  text-align: right;
}

@media (max-width: 809px) {
  .feature-list__item {
    flex-direction: column;
    gap: var(--space-1);
  }

  .feature-list__item span {
    text-align: left;
  }
}