/* AI 资讯 — mobile-first editorial */
:root {
  --paper: #f3eee6;
  --paper-deep: #e8e0d2;
  --card: #fffaf3;
  --ink: #1a1714;
  --ink-soft: #5c564e;
  --ink-faint: #8a8278;
  --line: #d6cec0;
  --accent: #8f2d1f;
  --accent-hover: #6f2116;
  --quote-bg: #faf6ee;
  --shadow: 0 1px 2px rgba(26, 23, 20, 0.04), 0 8px 24px rgba(26, 23, 20, 0.06);
  --radius: 14px;
  --max: 40rem;
  --sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --serif: "Noto Serif SC", "Songti SC", "Source Han Serif SC", Georgia, "Times New Roman", serif;
  --serif-en: "Newsreader", "Noto Serif SC", Georgia, serif;
  --header-h: 3.5rem;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: calc(var(--header-h) + env(safe-area-inset-top, 0px));
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.7;
  font-weight: 400;
  min-height: 100dvh;
  overflow-x: hidden;
}

img, video { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
a:hover { color: var(--accent-hover); }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.wrap {
  width: min(var(--max), 100%);
  margin: 0 auto;
  padding-left: max(1.5rem, env(safe-area-inset-left));
  padding-right: max(1.5rem, env(safe-area-inset-right));
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(16px) saturate(1.2);
  -webkit-backdrop-filter: blur(16px) saturate(1.2);
  border-bottom: 1px solid var(--line);
  padding-top: env(safe-area-inset-top, 0px);
}

.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
  color: inherit;
  text-decoration: none;
  min-height: 44px;
}

.brand-mark {
  display: inline-block;
  width: 0.55rem;
  height: 0.55rem;
  background: var(--accent);
  border-radius: 1px;
  transform: translateY(-0.08em);
  flex-shrink: 0;
}

.brand-name {
  font-family: var(--serif);
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: 0.04em;
}

.header-tag {
  font-size: 0.75rem;
  color: var(--ink-faint);
  letter-spacing: 0.08em;
}

/* Home */
.page-hero {
  padding: 1.6rem 0 1.15rem;
}

.page-hero h1 {
  margin: 0 0 0.4rem;
  font-family: var(--serif);
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: 0.02em;
}

.page-hero p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.98rem;
}

.feed {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  padding-bottom: 2.5rem;
}

.card {
  display: block;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  color: inherit;
  text-decoration: none;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.card:active { transform: scale(0.995); }

.card-cover {
  aspect-ratio: 16 / 9;
  background: var(--paper-deep);
  overflow: hidden;
  position: relative;
}

.card-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.card-badge {
  position: absolute;
  left: 0.75rem;
  bottom: 0.75rem;
  background: rgba(26, 23, 20, 0.82);
  color: #fffaf3;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  padding: 0.22rem 0.5rem;
  border-radius: 999px;
}

.card-body {
  padding: 1.05rem 1.05rem 1.2rem;
}

.card-date {
  margin: 0 0 0.45rem;
  font-size: 0.78rem;
  color: var(--ink-faint);
  letter-spacing: 0.02em;
}

.card-title {
  margin: 0 0 0.35rem;
  font-family: var(--serif);
  font-size: 1.28rem;
  font-weight: 700;
  line-height: 1.4;
}

.card-title-en {
  margin: 0 0 0.7rem;
  font-family: var(--serif-en);
  font-size: 1.02rem;
  font-weight: 500;
  font-style: italic;
  line-height: 1.45;
  color: var(--ink-soft);
}

.card-intro,
.card-intro-en {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.95rem;
  line-height: 1.7;
}

.card-intro-en {
  margin-top: 0.45rem;
  font-size: 0.9rem;
}

/* Article */
.article {
  padding: 1.65rem max(1.85rem, env(safe-area-inset-right)) 3.25rem max(1.85rem, env(safe-area-inset-left));
}

.back {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-height: 44px;
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.92rem;
  margin-left: -0.25rem;
}

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

.article-date {
  margin: 0.4rem 0 0.75rem;
  font-size: 0.82rem;
  color: var(--ink-faint);
}

.article-title {
  margin: 0 0 0.4rem;
  font-family: var(--serif);
  font-size: 1.72rem;
  font-weight: 700;
  line-height: 1.32;
}

.article-title-en {
  margin: 0 0 1.25rem;
  font-family: var(--serif-en);
  font-size: 1.15rem;
  font-weight: 500;
  font-style: italic;
  line-height: 1.45;
  color: var(--ink-soft);
}

.dek {
  margin: 1.15rem 0 0.65rem;
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--ink);
}

.dek-en {
  margin: 0 0 1.45rem;
  font-size: 0.98rem;
  line-height: 1.75;
  color: var(--ink-soft);
}

.rule {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 0 0 1.5rem;
}

.guide {
  margin: 0 0 1.75rem;
}

.guide .section-label {
  margin-bottom: 0.95rem;
}

.guide-heading {
  margin: 1.05rem 0 0.4rem;
  font-family: var(--sans);
  font-size: 1.02rem;
  font-weight: 650;
  line-height: 1.45;
}

.guide-heading:first-of-type { margin-top: 0; }

.guide-text {
  margin: 0;
  font-size: 0.98rem;
  line-height: 1.8;
  color: var(--ink);
}

.guide-text + .guide-heading { margin-top: 1.15rem; }

.guide-text a { overflow-wrap: anywhere; }


.section-label {
  margin: 0 0 0.85rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

/* Original posts */
.origin {
  background: var(--quote-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.1rem 1.05rem 1.15rem;
  margin-bottom: 1rem;
}

.origin.quoted {
  margin-left: 0.7rem;
  border-left: 3px solid var(--accent);
}

.origin-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.35rem 0.6rem;
  margin-bottom: 0.35rem;
}

.origin-author {
  font-weight: 600;
  font-size: 1rem;
}

.origin-handle {
  color: var(--ink-faint);
  font-size: 0.9rem;
}

.origin-time {
  flex-basis: 100%;
  font-size: 0.78rem;
  color: var(--ink-faint);
}

.origin-text {
  margin: 0.7rem 0 0.9rem;
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 1.05rem;
  line-height: 1.75;
}

.origin-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 0.92rem;
}

/* Video */
.player-block { margin: 0 0 0.35rem; }

.player {
  background: #14110e;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
}

.player video {
  width: 100%;
  height: auto;
  max-height: 80svh;
  aspect-ratio: 16 / 9;
  background: #000;
}

.caption-note {
  margin: 0.8rem 0 0;
  font-size: 0.85rem;
  color: var(--ink-soft);
  line-height: 1.65;
}

.caption-note + .caption-note { margin-top: 0.25rem; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.4rem 0 calc(1.6rem + env(safe-area-inset-bottom));
  color: var(--ink-faint);
  font-size: 0.82rem;
}

/* 404 */
.not-found {
  padding: 3.5rem 0 4rem;
  text-align: center;
}

.not-found h1 {
  font-family: var(--serif);
  font-size: 1.6rem;
  margin: 0 0 0.6rem;
}

@media (min-width: 640px) {
  body { font-size: 18px; }
  .article-title { font-size: 2rem; }
  .card-title { font-size: 1.38rem; }
  .page-hero h1 { font-size: 2.05rem; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}