/* =========================================================================
   english-number.com — shared guide styles
   Keep this file tiny and stable. Every /guides/*.html links to it.
   ========================================================================= */

:root {
  --color-text: #1f2328;
  --color-text-soft: #57606a;
  --color-heading: #0a0d12;
  --color-link: #0b5ed7;
  --color-link-hover: #084298;
  --color-border: #e5e7eb;
  --color-bg-soft: #f6f8fa;
  --color-bg-tip: #eaf5ff;
  --color-bg-warn: #fff8e1;
  --color-bg-callout-border: #b6dcff;
  --color-cta-bg: #111;
  --color-cta-bg-hover: #000;
  --max-width: 680px;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-heading: var(--font-body);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: #fff;
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ---- Site header ---- */
.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: 16px 24px;
}
.site-header__inner {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--color-heading);
  text-decoration: none;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
}
.site-header__brand img { width: 36px; height: 36px; }

.site-header__lang {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-soft);
}
.site-header__lang a {
  color: var(--color-text-soft);
  text-decoration: none;
  padding: 2px 6px;
  border-radius: 4px;
}
.site-header__lang a:hover {
  color: var(--color-heading);
  background: var(--color-bg-soft);
}
.site-header__lang a.is-active {
  color: var(--color-heading);
  font-weight: 700;
}
.site-header__lang span {
  color: var(--color-border);
}

/* ---- Article layout ---- */
.article {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 32px 24px 64px;
}

.breadcrumb {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: 16px;
}
.breadcrumb a {
  color: var(--color-text-soft);
  text-decoration: none;
}
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb__sep { margin: 0 6px; }

.article__meta {
  font-size: 14px;
  color: var(--color-text-soft);
  margin: 8px 0 24px;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-heading);
  font-weight: 700;
  line-height: 1.25;
}
h1 { font-size: 34px; margin: 0 0 16px; letter-spacing: -0.01em; }
h2 { font-size: 26px; margin: 40px 0 14px; }
h3 { font-size: 20px; margin: 28px 0 10px; }
h4 { font-size: 17px; margin: 22px 0 8px; }

p { margin: 0 0 18px; }
ul, ol { margin: 0 0 18px; padding-left: 24px; }
li { margin-bottom: 6px; }
strong { font-weight: 700; color: var(--color-heading); }
em { font-style: italic; }

a { color: var(--color-link); text-decoration: underline; text-underline-offset: 2px; }
a:hover { color: var(--color-link-hover); }

hr {
  border: 0;
  border-top: 1px solid var(--color-border);
  margin: 40px 0;
}

/* ---- Callout boxes ---- */
.callout {
  border: 1px solid var(--color-callout-border);
  background: var(--color-bg-tip);
  border-radius: 8px;
  padding: 16px 20px;
  margin: 24px 0;
}
.callout--warn {
  border-color: #f6c244;
  background: var(--color-bg-warn);
}
.callout__label {
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-heading);
  margin-bottom: 6px;
}
.callout p:last-child { margin-bottom: 0; }

/* ---- Audio example rows ---- */
.audio-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px 16px;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--color-border);
}
.audio-row:last-child { border-bottom: 0; }
.audio-row__label {
  font-weight: 700;
  font-size: 16px;
  min-width: 120px;
}
.audio-row audio {
  height: 36px;
  width: 100%;
  max-width: 320px;
}

/* ---- Example table (minimal-pair style) ---- */
.pair-table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 16px;
}
.pair-table th,
.pair-table td {
  border: 1px solid var(--color-border);
  padding: 10px 14px;
  text-align: left;
  vertical-align: top;
}
.pair-table th {
  background: var(--color-bg-soft);
  font-weight: 700;
}

/* ---- CTA ---- */
.cta {
  background: var(--color-bg-soft);
  border-radius: 10px;
  padding: 24px;
  margin: 40px 0;
  text-align: center;
}
.cta__title {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 6px;
  color: var(--color-heading);
}
.cta__sub {
  color: var(--color-text-soft);
  margin: 0 0 16px;
  font-size: 15px;
}
.cta__button {
  display: inline-block;
  background: var(--color-cta-bg);
  color: #fff;
  padding: 12px 24px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 700;
  font-size: 16px;
}
.cta__button:hover { background: var(--color-cta-bg-hover); color: #fff; }

/* ---- Related guides ---- */
.related {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}
.related h3 { margin-top: 0; }
.related ul { padding-left: 20px; }

/* ---- Footer ---- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 24px;
  font-size: 14px;
  color: var(--color-text-soft);
}
.site-footer__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  justify-content: space-between;
}
.site-footer a { color: var(--color-text-soft); }

/* ---- Numblr banner (shared across EN + ZH landing) ---- */
.numblr-banner {
  background: #f0fdfa;
  border: 1px solid #a5f3fc;
  border-radius: 8px;
  padding: 10px 14px;
  margin: 20px 0 32px;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 14px;
}
.numblr-banner__text {
  flex: 1;
  min-width: 220px;
  margin: 0;
  color: var(--color-text);
  line-height: 1.45;
}
.numblr-banner__text strong {
  color: var(--color-heading);
}
.numblr-banner__button {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #a5f3fc;
  border-bottom: 2px solid #67e8f9;
  color: #000;
  padding: 6px 14px;
  border-radius: 5px;
  text-decoration: none;
  font-weight: 700;
  font-size: 13px;
  white-space: nowrap;
}
.numblr-banner__button:hover {
  background: #67e8f9;
  color: #000;
}
.numblr-banner__button img {
  width: 16px;
  height: 16px;
}

/* ---- Landing-page hero (used by /zh/ home) ---- */
.landing {
  max-width: 680px;
  margin: 0 auto;
  padding: 48px 24px 120px;
}

.landing__hero {
  text-align: center;
  padding: 40px 0 48px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 40px;
}

.landing__hero h1 {
  font-size: 36px;
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}

.landing__hero p {
  font-size: 18px;
  color: var(--color-text-soft);
  margin: 0 0 32px;
}

.landing__hero .cta__button {
  font-size: 18px;
  padding: 14px 32px;
}

.landing h2 {
  font-size: 24px;
  margin: 36px 0 12px;
}

.landing h3 {
  font-size: 17px;
  margin: 24px 0 8px;
}

.landing ul,
.landing ol {
  padding-left: 22px;
}

.landing ul li,
.landing ol li {
  margin-bottom: 6px;
}

/* ---- Responsive ---- */
@media (max-width: 520px) {
  html, body { font-size: 17px; }
  h1 { font-size: 28px; }
  h2 { font-size: 22px; }
  h3 { font-size: 18px; }
  .article { padding: 24px 16px 48px; }
  .audio-row {
    grid-template-columns: 1fr;
    gap: 4px;
  }
}