/* AI 日报 — self-hosted static site.
   Mobile-first, Chinese-first, no framework, no external assets. */

:root {
  color-scheme: light dark;

  --paper: #fdfcf9;
  --canvas: #f3f1ec;
  --raise: #ffffff;
  --ink: #1d1e1c;
  --ink-soft: #4a4d47;
  --muted: #6f726b;
  --faint: #8b8e86;
  --rule: #ddd9d0;
  --rule-soft: #eae7df;
  --accent: #a1441c;
  --accent-strong: #8a3714;
  --accent-soft: #f8ede5;
  --notice-bg: #f4f1e6;
  --notice-rule: #cbbf95;
  --notice-ink: #5c5330;
  --lead-rule: var(--accent);
  --follow-rule: #c3bcae;

  --font-sans:
    -apple-system, BlinkMacSystemFont, "PingFang SC", "HarmonyOS Sans SC",
    "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", "Hiragino Sans GB",
    "Helvetica Neue", Arial, sans-serif;
  --font-mono:
    ui-monospace, "SFMono-Regular", "SF Mono", Menlo, Consolas,
    "Liberation Mono", monospace;

  --measure: 44rem;
  --gutter: 1.15rem;
  --radius: 6px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #16181a;
    --canvas: #101214;
    --raise: #1c1f21;
    --ink: #e9e7e2;
    --ink-soft: #c3c1ba;
    --muted: #9a9891;
    --faint: #7e7c76;
    --rule: #33383c;
    --rule-soft: #262b2e;
    --accent: #e08a5c;
    --accent-strong: #f0a276;
    --accent-soft: #2a211c;
    --notice-bg: #23211a;
    --notice-rule: #6b6142;
    --notice-ink: #d6cba6;
    --lead-rule: var(--accent);
    --follow-rule: #3d4348;
  }
}

/* ---------- reset ---------- */

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

html {
  -webkit-text-size-adjust: 100%;
  background: var(--canvas);
  scroll-behavior: smooth;
}

body {
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.78;
  margin: 0;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
p,
ul,
ol,
figure {
  margin: 0;
  padding: 0;
}

ul,
ol {
  list-style: none;
}

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

a:hover {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

a:focus-visible,
summary:focus-visible {
  border-radius: 2px;
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

strong {
  color: var(--ink);
  font-weight: 700;
}

time {
  font-variant-numeric: tabular-nums;
}

/* ---------- shell ---------- */

.site-header {
  align-items: baseline;
  background: var(--paper);
  border-bottom: 1px solid var(--rule);
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1rem;
  justify-content: space-between;
  padding: 0.9rem var(--gutter);
}

.site-title {
  color: var(--ink);
  font-size: 1.05rem;
  font-weight: 750;
  letter-spacing: 0.01em;
}

.site-title:hover {
  text-decoration: none;
}

.site-nav {
  display: flex;
  gap: 1rem;
}

.site-nav a {
  color: var(--muted);
  font-size: 0.86rem;
}

.site-main {
  background: var(--paper);
  margin: 0 auto;
  max-width: var(--measure);
  min-height: 60vh;
  padding: 1.4rem var(--gutter) 2.4rem;
}

.site-footer {
  border-top: 1px solid var(--rule);
  color: var(--faint);
  font-size: 0.78rem;
  line-height: 1.7;
  margin: 0 auto;
  max-width: var(--measure);
  padding: 1.4rem var(--gutter) 2.6rem;
}

.site-footer__home a {
  color: var(--faint);
}

.page-title {
  font-size: 1.35rem;
  font-weight: 760;
  letter-spacing: -0.01em;
  margin-bottom: 1.1rem;
}

/* ---------- issue head ---------- */

.issue-head {
  align-items: baseline;
  border-bottom: 2px solid var(--ink);
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 0.8rem;
  justify-content: space-between;
  padding-bottom: 0.55rem;
}

.issue-kicker {
  font-size: 1.22rem;
  font-weight: 780;
  letter-spacing: -0.01em;
  line-height: 1.4;
}

.issue-sep {
  color: var(--faint);
  font-weight: 400;
}

.issue-level {
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.issue-level--l1,
.issue-level--l2a,
.issue-level--l2b,
.issue-level--l3 {
  color: var(--notice-ink);
}

.issue-highlight {
  border-left: 3px solid var(--accent);
  color: var(--ink-soft);
  font-size: 1rem;
  line-height: 1.75;
  margin: 1.15rem 0 1.6rem;
  padding: 0.1rem 0 0.1rem 0.85rem;
}

.issue-permalink {
  border-top: 1px solid var(--rule-soft);
  font-size: 0.9rem;
  margin-top: 1.6rem;
  padding-top: 0.9rem;
}

/* ---------- notice banner ---------- */

.notice {
  background: var(--notice-bg);
  border: 1px solid var(--notice-rule);
  border-radius: var(--radius);
  color: var(--notice-ink);
  font-size: 0.92rem;
  line-height: 1.7;
  margin: 1.15rem 0 0;
  padding: 0.75rem 0.9rem;
}

.notice__text {
  font-weight: 600;
}

.notice__reasons {
  border-top: 1px solid var(--notice-rule);
  font-size: 0.84rem;
  margin-top: 0.5rem;
  padding-top: 0.45rem;
}

.notice__reasons li::before {
  content: "—";
  margin-right: 0.45rem;
  opacity: 0.7;
}

/* ---------- sections ---------- */

.section {
  margin-top: 2.2rem;
}

.section-title {
  border-bottom: 1px solid var(--rule);
  font-size: 0.76rem;
  font-weight: 780;
  letter-spacing: 0.16em;
  padding-bottom: 0.4rem;
}

.section--lead .section-title {
  border-bottom-color: var(--ink);
  color: var(--ink);
}

.section--follow .section-title,
.section--brief .section-title,
.section--viewpoint .section-title,
.section--recent .section-title {
  color: var(--muted);
}

/* ---------- story cards ---------- */

.story {
  border-bottom: 1px solid var(--rule-soft);
  padding: 1.35rem 0 1.25rem;
}

.section .story:last-of-type {
  border-bottom: 0;
  padding-bottom: 0.4rem;
}

.story-headline {
  font-size: 1.12rem;
  font-weight: 760;
  letter-spacing: -0.008em;
  line-height: 1.5;
  margin-bottom: 0.6rem;
  padding-left: 0.7rem;
  border-left: 3px solid var(--follow-rule);
}

.story--lead .story-headline {
  border-left-color: var(--lead-rule);
  font-size: 1.22rem;
}

.story p {
  color: var(--ink-soft);
  margin-bottom: 0.7rem;
}

.story-tldr {
  color: var(--ink);
}

.story-facts {
  background: var(--canvas);
  border-radius: var(--radius);
  margin: 0.2rem 0 0.85rem;
  padding: 0.7rem 0.85rem 0.75rem;
}

.story-label {
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  margin-bottom: 0.35rem;
}

.story-fact {
  color: var(--ink-soft);
  display: flex;
  font-size: 0.97rem;
  gap: 0.55rem;
  line-height: 1.72;
  margin-bottom: 0.3rem;
}

.story-fact:last-child {
  margin-bottom: 0;
}

.story-fact::before {
  color: var(--accent);
  content: "·";
  font-weight: 800;
}

.story-caveat {
  color: var(--muted);
  font-size: 0.94rem;
}

.story-sources {
  font-size: 0.9rem;
}

.story-meta,
.brief-meta {
  color: var(--faint);
  font-family: var(--font-mono);
  font-size: 0.71rem;
  letter-spacing: 0.01em;
}

.story-meta {
  margin-bottom: 0;
}

.source-link {
  display: inline-block;
  min-height: 24px;
  padding: 0.1rem 0;
}

.source-sep,
.story-sep,
.brief-sep,
.fallback-sep {
  color: var(--faint);
}

.story-category {
  color: var(--muted);
}

/* ---------- brief list ---------- */

.brief-list {
  counter-reset: brief;
  margin-top: 0.4rem;
}

.brief {
  border-bottom: 1px solid var(--rule-soft);
  counter-increment: brief;
  display: grid;
  gap: 0.15rem 0.7rem;
  grid-template-columns: 1.9rem 1fr;
  padding: 0.85rem 0;
}

.brief:last-child {
  border-bottom: 0;
}

.brief::before {
  color: var(--accent);
  content: counter(brief, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 700;
  grid-row: 1 / span 3;
  padding-top: 0.35rem;
}

.brief-headline {
  color: var(--ink);
  font-size: 0.99rem;
  font-weight: 720;
  line-height: 1.55;
}

.brief-category {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 500;
  margin-left: 0.5rem;
  white-space: nowrap;
}

.brief-text {
  color: var(--ink-soft);
  font-size: 0.96rem;
  line-height: 1.72;
}

.brief-meta {
  margin-top: 0.15rem;
}

/* ---------- viewpoints ---------- */

.viewpoint {
  border-left: 2px solid var(--rule);
  margin-top: 1rem;
  padding-left: 0.85rem;
}

.viewpoint-text {
  color: var(--ink-soft);
  font-size: 0.99rem;
}

.viewpoint-sources {
  font-size: 0.82rem;
  margin-top: 0.15rem;
}

/* ---------- recent + archive ---------- */

.recent {
  border-bottom: 1px solid var(--rule-soft);
}

.recent a {
  align-items: baseline;
  color: var(--ink);
  display: flex;
  flex-wrap: wrap;
  gap: 0.1rem 0.75rem;
  padding: 0.65rem 0;
}

.recent-date,
.archive-date {
  color: var(--faint);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  white-space: nowrap;
}

.recent-headline,
.archive-headline {
  flex: 1 1 14rem;
  font-size: 0.97rem;
  line-height: 1.6;
}

.recent-more {
  font-size: 0.88rem;
  margin-top: 0.9rem;
}

.archive-list {
  border-top: 1px solid var(--rule);
}

.archive-row {
  border-bottom: 1px solid var(--rule-soft);
  padding: 0.6rem 0;
}

.archive-link {
  align-items: baseline;
  color: var(--ink);
  display: flex;
  flex-wrap: wrap;
  gap: 0.1rem 0.7rem;
}

.archive-weekday {
  color: var(--faint);
  font-size: 0.74rem;
}

.archive-meta {
  color: var(--faint);
  display: flex;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  gap: 0.7rem;
  padding-left: 0;
  padding-top: 0.1rem;
}

.archive-row--missing {
  align-items: baseline;
  display: flex;
  flex-wrap: wrap;
  gap: 0.1rem 0.7rem;
}

.archive-row--missing .archive-date,
.archive-row--missing .archive-weekday {
  opacity: 0.65;
}

.archive-missing {
  color: var(--faint);
  font-size: 0.86rem;
}

.archive-empty {
  color: var(--muted);
}

/* ---------- fallback ---------- */

.fallback-text {
  color: var(--ink-soft);
  margin-top: 1.15rem;
}

.fallback-links {
  font-size: 0.9rem;
  margin-top: 1rem;
}

/* ---------- wider screens ---------- */

@media (min-width: 46rem) {
  :root {
    --gutter: 2rem;
  }

  body {
    font-size: 17px;
  }

  .site-main {
    border-left: 1px solid var(--rule);
    border-right: 1px solid var(--rule);
    min-height: 70vh;
    padding-top: 2rem;
  }

  .issue-kicker {
    font-size: 1.42rem;
  }

  .story--lead .story-headline {
    font-size: 1.3rem;
  }

  .brief {
    grid-template-columns: 2.2rem 1fr;
  }
}

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