:root {
  color-scheme: light;
  --palette-blue: #5aa9e6;
  --palette-sky: #7fc8f8;
  --palette-paper: #f9f9f9;
  --palette-sun: #ffe45e;
  --palette-pink: #ff6392;
  --bg: var(--palette-paper);
  --bg-soft: #eef8ff;
  --surface: #ffffff;
  --surface-quiet: #f1f9ff;
  --text: #10263f;
  --muted: #355a78;
  --line: #b9daf2;
  --primary: #1d6fa8;
  --primary-strong: #144f79;
  --accent-color: var(--palette-pink);
  --accent-color-soft: #ffe6ef;
  --highlight-soft: #fff8d2;
  --code-bg: #ebf6ff;
}

* {
  box-sizing: border-box;
}

html {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  line-height: 1.65;
  color: var(--text);
  background:
    radial-gradient(circle at 12% 0%, var(--palette-sky) 0, transparent 34%),
    radial-gradient(circle at 90% 2%, var(--palette-sun) 0, transparent 28%),
    radial-gradient(circle at 86% 8%, var(--palette-pink) 0, transparent 22%),
    var(--bg);
  background-repeat: no-repeat;
}

a {
  color: var(--primary);
  text-decoration-thickness: 0.11em;
  text-underline-offset: 0.16em;
}

a:hover {
  color: var(--primary-strong);
}

.site-header {
  background: linear-gradient(90deg, #ffffff 0%, #f3faff 68%, #fff8d5 100%);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(8px);
}

.site-header-inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 0.9rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  margin: 0;
  font-size: 1.3rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--text);
  text-decoration: none;
}

.brand-bird {
  width: 46px;
  height: 46px;
  border-radius: 10px;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.33rem 0.72rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  text-decoration: none;
  color: var(--primary);
  font-weight: 600;
}

.site-nav a:hover {
  background: var(--bg-soft);
}

.container {
  width: 100%;
  flex: 1 0 auto;
  max-width: 860px;
  margin: 0 auto;
  padding: 1rem;
}

.timeline-heading h2 {
  margin: 0 0 0.2rem;
  display: inline-flex;
  align-items: center;
  gap: 0.48rem;
  font-size: 1.45rem;
}

.timeline-heading h2 i {
  color: var(--accent-color);
}

.timeline-heading p {
  margin: 0 0 0.65rem;
  color: var(--muted);
}

.note-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1rem 1.2rem;
  margin-bottom: 1rem;
  box-shadow: 0 8px 26px rgba(15, 56, 120, 0.07);
}

.note-card-header {
  margin-bottom: 0.74rem;
}

.note-card-header h2,
.note-card-header h3 {
  margin: 0 0 0.2rem;
  line-height: 1.34;
}

.note-card-header h3 a {
  text-decoration-thickness: 0.1em;
}

.note-card-header time {
  display: inline-flex;
  align-items: center;
  gap: 0.42rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.note-card-header time i {
  color: var(--accent-color);
}

.note-content {
  overflow-wrap: anywhere;
}

.note-content :first-child {
  margin-top: 0;
}

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

.note-content ul,
.note-content ol {
  padding-left: 1.2rem;
}

.note-content blockquote {
  margin: 0.95rem 0;
  padding: 0.2rem 0 0.2rem 0.9rem;
  border-left: 4px solid var(--accent-color);
  color: var(--muted);
  background: linear-gradient(90deg, var(--accent-color-soft) 0%, var(--highlight-soft) 100%);
  border-radius: 4px;
}

.note-content pre {
  margin: 0.95rem 0;
  background: var(--code-bg);
  border: 1px solid #b6c8e6;
  border-left: 4px solid var(--primary);
  border-radius: 10px;
  padding: 0.86rem;
  overflow-x: auto;
}

.note-content code {
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.93em;
}

.note-content :not(pre) > code {
  background: var(--code-bg);
  border: 1px solid #d4e0f2;
  border-radius: 6px;
  padding: 0.05rem 0.3rem;
}

.note-content img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
}

.embed-frame {
  background: linear-gradient(130deg, var(--highlight-soft) 0%, var(--bg-soft) 100%);
  border: 1px solid #cfddf2;
  border-left: 4px solid var(--accent-color);
  border-radius: 10px;
  padding: 0.78rem;
}

.permalink,
.back-link {
  margin: 0.82rem 0 0;
}

.permalink a,
.back-link a {
  display: inline-flex;
  align-items: center;
  gap: 0.42rem;
  font-weight: 600;
  text-decoration: none;
}

.permalink a:hover,
.back-link a:hover {
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

.pager {
  display: flex;
  justify-content: space-between;
  gap: 0.7rem;
  margin: 1.12rem 0 0.4rem;
}

.pager-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  border-radius: 999px;
  padding: 0.35rem 0.82rem;
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--surface);
  font-weight: 600;
}

.pager-link:hover {
  background: var(--surface-quiet);
}

.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--line);
  background: linear-gradient(90deg, #ffffff 0%, #f0f8ff 68%, #fff7cd 100%);
}

.site-footer-inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 0.9rem 1rem 1.15rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo-mark {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.logo-mark img {
  width: 38px;
  height: 38px;
}

.site-footer p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

@media (max-width: 640px) {
  .site-header-inner,
  .site-footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .site-nav {
    gap: 0.75rem;
  }
}