/* N884 AI Brief — global stylesheet (mobile first) */

:root {
  --bg: #ffffff;
  --text: #111318;
  --muted: #5b6472;
  --accent: #2563eb;
  --accent-2: #7c3aed;
  --line: #e5e8ee;
  --surface: #f7f8fa;
  --maxw: 1200px;
  --ui: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --body: "Georgia", "Noto Serif", serif;
}

* { box-sizing: border-box; }

html { font-size: 16px; }

body {
  margin: 0;
  font-family: var(--ui);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-text-size-adjust: 100%;
}

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

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; margin: 0 0 0.5em; }

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

.main { padding: 24px 20px; }

/* ---------- header ---------- */
.hd {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.97);
  border-bottom: 1px solid var(--line);
}

.hd__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  padding-top: 12px;
  padding-bottom: 12px;
}

.hd__logo {
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--text);
}
.hd__logo img { max-height: 36px; width: auto; }
.hd__logo:hover { text-decoration: none; color: var(--accent); }

.hd__toggle {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
  margin-left: auto;
  background: none;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 8px 9px;
  cursor: pointer;
}
.hd__toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
}

.hd__nav {
  display: none;
  flex-basis: 100%;
  flex-direction: column;
  gap: 2px;
  order: 4;
  padding: 8px 0 4px;
  border-top: 1px solid var(--line);
}
.hd__nav.is-active { display: flex; }

.hd__navlink {
  padding: 8px 10px;
  color: var(--text);
  font-weight: 500;
  border-radius: 6px;
}
.hd__navlink:hover { background: var(--surface); text-decoration: none; }
.hd__navlink.is-current { color: var(--accent); font-weight: 700; }

.hd__search {
  display: flex;
  flex-basis: 100%;
  order: 5;
  gap: 8px;
}
.hd__search input {
  flex: 1;
  font: inherit;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  color: var(--text);
}
.hd__search input:focus { outline: 2px solid var(--accent); outline-offset: -1px; background: var(--bg); }
.hd__search button {
  font: inherit;
  font-weight: 600;
  padding: 8px 16px;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
}
.hd__search button:hover { background: var(--accent-2); }

/* ---------- generic page elements ---------- */
.crumb {
  font-size: 0.875rem;
  color: var(--muted);
  margin-bottom: 16px;
}
.crumb a { color: var(--muted); }
.crumb a:hover { color: var(--accent); }

.page-title { font-size: 1.75rem; letter-spacing: -0.02em; margin-bottom: 8px; }
.page-intro { color: var(--muted); margin: 0 0 24px; max-width: 60ch; }

.section-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  border-bottom: 2px solid var(--text);
  margin: 32px 0 16px;
  padding-bottom: 8px;
}
.section-head h2 { font-size: 1.25rem; margin: 0; }
.section-head .more { font-size: 0.875rem; font-weight: 600; }

.meta {
  font-size: 0.8125rem;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
}
.meta a { color: var(--muted); }
.meta a:hover { color: var(--accent); }

/* ---------- cards ---------- */
.card { border-bottom: 1px solid var(--line); padding: 16px 0; }
.card:last-child { border-bottom: none; }

.card__media img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: 8px;
  background: var(--surface);
}

.card__title { font-size: 1.0625rem; margin: 10px 0 6px; line-height: 1.35; }
.card__title a { color: var(--text); }
.card__title a:hover { color: var(--accent); text-decoration: none; }

.card__summary { color: var(--muted); font-size: 0.9375rem; margin: 0 0 8px; }

.card__meta { display: flex; flex-wrap: wrap; gap: 6px 12px; font-size: 0.8125rem; color: var(--muted); }
.card__meta a { color: var(--muted); }

/* thumbnails left on list cards */
.card--row { display: grid; grid-template-columns: 120px 1fr; gap: 14px; }
.card--row .card__media img { aspect-ratio: 4 / 3; height: 100%; }
.card--row .card__title { margin-top: 0; }

/* ---------- home: lead + latest ---------- */
.lead { margin-bottom: 8px; }
.lead__inner { display: grid; gap: 28px; }

.lead__story .card__media img { aspect-ratio: 16 / 9; border-radius: 10px; }
.lead__story .card__title { font-size: 1.5rem; margin-top: 14px; }
.lead__story .card__summary { font-size: 1rem; }

.latest-list { list-style: none; margin: 0; padding: 0; }
.latest-list li {
  display: grid;
  grid-template-columns: 2rem 1fr;
  gap: 10px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}
.latest-list li:last-child { border-bottom: none; }
.latest-list .num {
  color: var(--accent-2);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.latest-list a { color: var(--text); font-weight: 600; }
.latest-list a:hover { color: var(--accent); text-decoration: none; }
.latest-list time { display: block; font-size: 0.8125rem; color: var(--muted); margin-top: 2px; }

.latest-panel h2 {
  font-size: 1.25rem;
  border-bottom: 2px solid var(--text);
  padding-bottom: 8px;
}

/* ---------- home: category sections ---------- */
.cat-section .cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

/* ---------- tags ---------- */
.tag {
  display: inline-block;
  padding: 3px 10px;
  margin: 0 6px 6px 0;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
}
.tag:hover { background: var(--accent); border-color: var(--accent); color: #fff; text-decoration: none; }

/* tag cloud sizes by weight */
.cloud .tag--w1 { font-size: 0.8125rem; }
.cloud .tag--w2 { font-size: 0.9375rem; }
.cloud .tag--w3 { font-size: 1.0625rem; }
.cloud .tag--w4 { font-size: 1.25rem; }
.cloud .tag--w5 { font-size: 1.4375rem; font-weight: 700; color: var(--accent-2); }

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  font: inherit;
  font-weight: 600;
  padding: 9px 18px;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text);
  background: var(--bg);
  cursor: pointer;
}
.btn:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.btn--accent { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn--accent:hover { background: var(--accent-2); border-color: var(--accent-2); color: #fff; }

/* ---------- sidebar ---------- */
.sidebar { margin-top: 40px; border-top: 2px solid var(--text); padding-top: 8px; }
.sidebar__block { padding: 12px 0 24px; border-bottom: 1px solid var(--line); }
.sidebar__block:last-child { border-bottom: none; }
.sidebar__title { font-size: 1rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); margin-bottom: 12px; }
.sidebar__guides { list-style: none; margin: 0; padding: 0; }
.sidebar__guide { padding: 8px 0; border-bottom: 1px dashed var(--line); }
.sidebar__guide:last-child { border-bottom: none; }
.sidebar__guide-link { display: block; color: var(--text); font-weight: 600; line-height: 1.4; }
.sidebar__guide-link:hover { color: var(--accent); text-decoration: none; }
.sidebar__guide-date { font-size: 0.8125rem; color: var(--muted); }
.sidebar__tags { line-height: 1.8; }
.sidebar__empty { color: var(--muted); font-size: 0.875rem; }

/* ---------- pager ---------- */
.pager {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 32px 0;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.pager__link {
  min-width: 40px;
  text-align: center;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text);
}
.pager__link:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.pager__link.is-current { background: var(--accent); border-color: var(--accent); color: #fff; }
.pager__link--prev { margin-right: auto; }
.pager__link--next { margin-left: auto; }

/* ---------- article body ---------- */
.article-head { margin-bottom: 24px; }
.article-head h1 { font-size: 1.875rem; letter-spacing: -0.02em; }

.summary {
  font-size: 1.0625rem;
  color: var(--muted);
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 14px;
  margin: 0 0 24px;
}

.body {
  font-family: var(--body);
  font-size: 18px;
  line-height: 1.7;
  max-width: 46rem;
}
.body p { margin: 0 0 1.2em; }
.body h2, .body h3 { font-family: var(--ui); }
.body img { border-radius: 8px; margin: 24px 0; }
.body blockquote {
  margin: 24px 0;
  padding: 8px 20px;
  border-left: 3px solid var(--accent-2);
  color: var(--muted);
}
.body ul, .body ol { padding-left: 1.4em; margin: 0 0 1.2em; }

.table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--line);
  border-radius: 8px;
}
.table-wrap table { border-collapse: collapse; width: 100%; }
.body table { border-collapse: collapse; width: 100%; margin: 24px 0; display: block; overflow-x: auto; }
.body th, .body td { padding: 10px 14px; border-bottom: 1px solid var(--line); text-align: left; font-size: 16px; }
.body th { background: var(--surface); font-family: var(--ui); font-weight: 700; }

.body pre {
  background: #14161c;
  color: #e8eaf0;
  padding: 18px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 0.875rem;
  line-height: 1.6;
  margin: 24px 0;
}
.body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  background: var(--surface);
  padding: 2px 5px;
  border-radius: 4px;
  font-size: 0.9em;
}
.body pre code { background: none; padding: 0; }

.tags-line { margin: 24px 0; font-size: 0.9375rem; color: var(--muted); }
.tags-line a { margin-right: 4px; }

.prevnext {
  display: grid;
  gap: 12px;
  margin: 32px 0;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  font-size: 0.9375rem;
}
.prevnext a { color: var(--text); font-weight: 600; }
.prevnext a:hover { color: var(--accent); }

.related__list { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.related__list .card { border-bottom: 1px solid var(--line); }

/* ---------- topics ---------- */
.topic-hero { position: relative; margin-bottom: 24px; }
.topic-hero img {
  width: 100%;
  max-height: 320px;
  object-fit: cover;
  border-radius: 10px;
}
.topics-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin: 24px 0;
}
.topic-card {
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  display: block;
  color: var(--text);
}
.topic-card:hover { border-color: var(--accent); text-decoration: none; box-shadow: 0 4px 16px rgba(37, 99, 235, 0.08); }
.topic-card img { aspect-ratio: 16 / 9; object-fit: cover; width: 100%; }
.topic-card__body { padding: 14px 16px 18px; }
.topic-card__body h3 { font-size: 1.0625rem; margin: 0 0 6px; }
.topic-card__body p { color: var(--muted); font-size: 0.875rem; margin: 0 0 8px; }
.topic-card__count { font-size: 0.8125rem; color: var(--accent); font-weight: 600; }

/* ---------- search ---------- */
.search-filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0 24px; }
.search-filters a {
  padding: 5px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.875rem;
  color: var(--muted);
}
.search-filters a:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.search-filters a.is-current { background: var(--accent); border-color: var(--accent); color: #fff; }
.result-count { color: var(--muted); font-size: 0.9375rem; margin-bottom: 16px; }
.result-hl { font-weight: 700; }

/* ---------- misc ---------- */
.subcats { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 24px; }
.error-box { text-align: center; padding: 60px 0; }
.error-box h1 { font-size: 4rem; color: var(--accent); }

/* ---------- footer ---------- */
.ft {
  margin-top: 48px;
  background: var(--surface);
  border-top: 1px solid var(--line);
  padding: 32px 0 24px;
  font-size: 0.9375rem;
}
.ft__cols { display: grid; gap: 28px; }
.ft__name { font-weight: 800; margin: 0 0 6px; }
.ft__note { color: var(--muted); margin: 0; font-size: 0.8125rem; }
.ft__title {
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 0.75rem;
  color: var(--muted);
  margin: 0 0 10px;
}
.ft__link { display: block; color: var(--text); padding: 3px 0; }
.ft__link:hover { color: var(--accent); }
.ft__copy { color: var(--muted); font-size: 0.8125rem; margin: 24px 0 0; padding-top: 16px; border-top: 1px solid var(--line); }

/* ---------- ≥640px ---------- */
@media (min-width: 640px) {
  .lead__story .card__title { font-size: 1.875rem; }
  .cat-section .cards { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .card--row { grid-template-columns: 180px 1fr; }
  .topics-grid { grid-template-columns: repeat(2, 1fr); }
  .prevnext { grid-template-columns: 1fr 1fr; }
  .related__list { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .ft__cols { grid-template-columns: 1fr 1fr 1fr; }
  .page-title { font-size: 2.125rem; }
  .article-head h1 { font-size: 2.25rem; }
}

/* ---------- ≥960px ---------- */
@media (min-width: 960px) {
  .hd__toggle { display: none; }
  .hd__nav {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    flex-basis: auto;
    flex: 1;
    order: 2;
    border-top: none;
    padding: 0;
    gap: 0 4px;
    margin-left: 16px;
  }
  .hd__search { flex-basis: 240px; order: 3; }

  .main { padding-top: 32px; padding-bottom: 32px; }

  .with-sidebar {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 40px;
    align-items: start;
  }
  .sidebar { margin-top: 0; border-top: none; padding-top: 0; }
  .sidebar__block:first-child { padding-top: 0; }

  .lead__inner { grid-template-columns: 1.4fr 1fr; gap: 40px; }
  .cat-section .cards { grid-template-columns: repeat(4, 1fr); }
  .topics-grid { grid-template-columns: repeat(3, 1fr); }
}