:root {
  --header-height: 74px;
  --sidebar-width: clamp(310px, 24vw, 410px);
  --bg: #f4f0ff;
  --panel: #ffffff;
  --panel-2: #f1ebff;
  --text: #22183f;
  --muted: #5e5487;
  --accent: #6d3af2;
  --accent-2: #8f68ff;
  --border: #dbd1f4;
  --shadow: 0 10px 24px rgba(57, 35, 116, 0.1);
  --radius: 14px;
}

html[data-theme="dark"] {
  --bg: #171127;
  --panel: #211738;
  --panel-2: #2a1f45;
  --text: #f3eefe;
  --muted: #c3b6ec;
  --accent: #9c7dff;
  --accent-2: #b49dff;
  --border: #3a2d5b;
  --shadow: 0 12px 28px rgba(0, 0, 0, 0.38);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: "Space Grotesk", "Avenir Next", "Segoe UI", sans-serif;
  line-height: 1.65;
}

.topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 0.9rem;
  padding: 0 1rem;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

.topbar-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: inherit;
  min-width: 0;
}

.topbar-logo {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  flex: 0 0 auto;
  border: 0;
  box-shadow: none;
}

.topbar-brand-text {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.topbar-title {
  font-size: 1.18rem;
  font-weight: 700;
  line-height: 1.1;
}

.topbar-subtitle {
  margin-top: 0.08rem;
  font-size: 0.83rem;
  color: var(--muted);
  line-height: 1.15;
}

.icon-btn {
  width: 38px;
  height: 38px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  border-radius: 10px;
  cursor: pointer;
  font-size: 1rem;
  flex: 0 0 auto;
}

.icon-btn:hover { border-color: var(--accent); }

#nav-toggle { display: none; }
#theme-toggle { margin-left: auto; }

.sidebar {
  position: fixed;
  top: var(--header-height);
  left: 0;
  bottom: 0;
  width: var(--sidebar-width);
  border-right: 1px solid var(--border);
  background: var(--panel);
  overflow: auto;
  z-index: 30;
}

.sidebar__inner { padding: 1rem; }
.sidebar__inner {
  min-height: 100%;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

#sidebar-nav {
  flex: 1 1 auto;
}

.sidebar-footer {
  margin-top: auto;
  padding-top: 0.35rem;
}

.sidebar-footer img {
  width: 100%;
  max-width: 160px;
  height: auto;
  border-radius: 0;
  border: 0;
  box-shadow: none;
}

.layout {
  margin-left: var(--sidebar-width);
  padding-top: var(--header-height);
  min-height: 100vh;
}

.content {
  max-width: 980px;
  margin: 1.1rem auto 2rem;
  padding: 0 1rem;
}

.doc-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.4rem clamp(1rem, 2vw, 2rem) 1.2rem;
}

.fade-in { animation: fadeIn 320ms ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(6px);} to {opacity: 1; transform: translateY(0);} }

#sidebar-nav ul { list-style: none; margin: 0; padding: 0; }
#sidebar-nav li { margin-bottom: 0.3rem; }

.nav-link, .nav-summary {
  display: flex;
  align-items: center;
  width: 100%;
  border-radius: 10px;
  border: 1px solid transparent;
  color: var(--text);
  text-decoration: none;
  font-size: clamp(0.84rem, 0.62rem + 0.35vw, 0.92rem);
  padding: 0.5rem 0.6rem;
  background: transparent;
  white-space: nowrap;
}

.nav-summary { cursor: pointer; }
.nav-link:hover, .nav-summary:hover { background: var(--panel-2); border-color: var(--border); }

.nav-link[aria-current="page"] {
  background: var(--panel-2);
  border-color: var(--accent);
  font-weight: 600;
}

.nav-children {
  padding-left: 0.75rem;
  margin-top: 0.35rem;
  border-left: 1px dashed var(--border);
}

h1, h2, h3, h4 { scroll-margin-top: 96px; line-height: 1.2; }
h1 { margin: 0 0 0.5rem; font-size: clamp(1.45rem, 2.1vw, 2.1rem); }
h2 { margin-top: 1.4rem; padding-top: 0.25rem; border-top: 1px solid var(--border); font-size: clamp(1.08rem, 1.6vw, 1.35rem); }

a { color: var(--accent); }
a:hover { color: var(--accent-2); }

img {
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.doc-card a[href*="ko-fi.com"] img,
.sidebar-footer a[href*="ko-fi.com"] img {
  width: auto !important;
  max-width: min(100%, 150px) !important;
  height: auto !important;
  border: 0 !important;
  box-shadow: none !important;
  border-radius: 0 !important;
}

code, pre { font-family: "IBM Plex Mono", "Cascadia Code", monospace; }
pre {
  overflow: auto;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.75rem;
}

.quick-nav {
  margin-top: 1rem;
  margin-bottom: 1rem;
  padding: 0.8rem;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.quick-nav h2 {
  margin: 0 0 0.45rem;
  padding: 0;
  border: 0;
  font-size: 0.95rem;
}

.quick-nav ul { margin: 0; padding-left: 1rem; }
.quick-nav li { margin: 0.24rem 0; }
.quick-nav details > summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--text);
  list-style: none;
}
.quick-nav details > summary::-webkit-details-marker { display: none; }
.quick-nav details > summary::before {
  content: "▸";
  margin-right: 0.45rem;
  color: var(--muted);
}
.quick-nav details[open] > summary::before {
  content: "▾";
}
.quick-nav details ul {
  margin-top: 0.55rem;
}

.pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-top: 1.3rem;
  padding-top: 0.9rem;
  border-top: 1px solid var(--border);
}

.pager a {
  display: block;
  text-decoration: none;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.7rem 0.8rem;
  background: var(--panel-2);
}

.pager a span { display: block; font-size: 0.72rem; color: var(--muted); }
.pager a strong { display: block; margin-top: 0.1rem; font-size: 0.88rem; color: var(--text); }
.pager__next { text-align: right; }

.nav-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  border: 0;
  z-index: 25;
}

@media (max-width: 1040px) {
  #nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .topbar-title { font-size: 1.05rem; }
  .topbar-subtitle { font-size: 0.76rem; }

  .layout { margin-left: 0; }

  .sidebar {
    width: min(96vw, 560px);
    transform: translateX(-100%);
    transition: transform 180ms ease;
    top: var(--header-height);
  }

  .nav-link, .nav-summary {
    font-size: 0.92rem;
    padding: 0.46rem 0.52rem;
  }

  body.nav-open .sidebar { transform: translateX(0); }
  body.nav-open .nav-backdrop { display: block; }
}

@media (max-width: 640px) {
  .topbar {
    height: 66px;
    padding: 0 0.7rem;
    gap: 0.5rem;
  }

  .topbar-logo { width: 28px; height: 28px; }
  .topbar-title { font-size: 0.95rem; }
  .topbar-subtitle { display: none; }

  .nav-link, .nav-summary {
    font-size: 0.88rem;
    letter-spacing: -0.01em;
  }

  .pager { grid-template-columns: 1fr; }
  .pager__next { text-align: left; }

  .doc-card {
    padding: 1rem 0.85rem;
    border-radius: 12px;
  }
}