/* ============================================
   EinkBro Documentation — E-ink Editorial Theme
   Pure grayscale. Maximum legibility. Zero noise.
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Newsreader:ital,opsz,wght@0,6..72,300;0,6..72,400;0,6..72,500;0,6..72,600;0,6..72,700;1,6..72,400&family=Atkinson+Hyperlegible+Next:ital,wght@0,400;0,700;1,400&family=JetBrains+Mono:wght@400;500&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@24,400,0,0&display=swap');

/* --- Tokens --- */
:root {
  --ink: #111;
  --paper: #fdfdfd;
  --mid: #666;
  --faint: #e0e0e0;
  --hairline: #ccc;
  --wash: #f5f5f5;
  --font-heading: 'Newsreader', 'Georgia', serif;
  --font-body: 'Atkinson Hyperlegible Next', 'Verdana', sans-serif;
  --font-mono: 'JetBrains Mono', 'Menlo', monospace;
  --max-w: 1120px;
  --nav-h: 56px;
}

/* --- Reset --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 24px); }

body {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}

/* --- Typography --- */
h1, h2, h3, h4 { font-family: var(--font-heading); font-weight: 600; line-height: 1.25; }
h1 { font-size: 2.4rem; letter-spacing: -0.02em; }
h2 { font-size: 1.6rem; margin-top: 3rem; margin-bottom: 1rem; padding-bottom: 0.4rem; border-bottom: 2px solid var(--ink); }
h3 { font-size: 1.2rem; margin-top: 2rem; margin-bottom: 0.6rem; }
h4 { font-size: 1rem; margin-top: 1.4rem; margin-bottom: 0.4rem; font-weight: 700; }
p { margin-bottom: 1rem; }
a { color: var(--ink); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }
strong { font-weight: 700; }
code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--wash);
  padding: 1px 5px;
  border-radius: 3px;
  border: 1px solid var(--faint);
}
pre {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--ink);
  color: var(--paper);
  padding: 1.2rem 1.4rem;
  border-radius: 7px;
  overflow-x: auto;
  margin-bottom: 1.5rem;
  line-height: 1.6;
}
pre code { background: none; border: none; padding: 0; color: inherit; }
ul, ol { margin-bottom: 1rem; padding-left: 1.5rem; }
li { margin-bottom: 0.3rem; }
hr { border: none; border-top: 1px solid var(--hairline); margin: 2rem 0; }
img { max-width: 100%; height: auto; }

/* --- Layout --- */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 1.5rem; }

/* --- Navigation --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--ink);
  color: var(--paper);
  height: var(--nav-h);
  display: flex;
  align-items: center;
  border-bottom: 3px solid var(--ink);
}
.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}
.site-nav__logo {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--paper);
  text-decoration: none;
  letter-spacing: -0.01em;
}
.site-nav__links { display: flex; gap: 1.6rem; list-style: none; padding: 0; margin: 0; }
.site-nav__links a {
  color: rgba(255,255,255,0.75);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  transition: color 0.15s;
}
.site-nav__links a:hover,
.site-nav__links a.active { color: #fff; }
.nav-toggle { display: none; background: none; border: none; color: var(--paper); cursor: pointer; font-size: 1.5rem; line-height: 1; }

/* --- Hero --- */
.hero {
  text-align: center;
  padding: 5rem 1.5rem 4rem;
  border-bottom: 3px solid var(--ink);
}
.hero h1 {
  font-size: 3.4rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0.6rem;
}
.hero__tagline {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-style: italic;
  color: var(--mid);
  margin-bottom: 2rem;
}
.hero__cta {
  display: inline-block;
  background: var(--ink);
  color: var(--paper);
  padding: 0.7rem 2rem;
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  border: 2px solid var(--ink);
  border-radius: 7px;
  transition: background 0.15s, color 0.15s;
}
.hero__cta:hover { background: var(--paper); color: var(--ink); }

/* --- Feature Grid --- */
.features { padding: 4rem 0; border-bottom: 1px solid var(--hairline); }
.features__heading { text-align: center; margin-bottom: 2.5rem; border-bottom: none; padding-bottom: 0; }
.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}
.feature-card {
  border: 1px solid var(--ink);
  border-radius: 7px;
  padding: 1.6rem;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: background 0.15s, border-width 0.1s;
}
.feature-card:hover { background: var(--wash); border-width: 2px; }
.feature-card__icon {
  font-size: 1.8rem;
  margin-bottom: 0.6rem;
  display: block;
}
.feature-card h3 {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 600;
  margin-top: 0;
  margin-bottom: 0.5rem;
}
.feature-card p { font-size: 0.9rem; color: var(--mid); margin-bottom: 0; }

/* --- Screenshot Gallery --- */
.gallery { padding: 4rem 0; border-bottom: 1px solid var(--hairline); }
.gallery__heading { text-align: center; margin-bottom: 2rem; border-bottom: none; }
.gallery__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 1rem;
}
.gallery__item {
  border: 1px solid var(--hairline);
  border-radius: 7px;
  overflow: hidden;
  text-align: center;
}
.gallery__item img { width: 100%; display: block; }
.gallery__item figcaption {
  font-size: 0.78rem;
  padding: 0.4rem;
  color: var(--mid);
  border-top: 1px solid var(--faint);
}

/* --- Device Screenshots (click to enlarge) --- */
.device-img {
  display: block;
  width: 300px;
  border: 1px solid var(--ink);
  border-radius: 7px;
  margin: 1.5rem 0;
  cursor: pointer;
}
.device-img:hover { opacity: 0.85; border-width: 2px; }

/* --- Page Content --- */
.page-content { padding: 3rem 0 4rem; }

/* --- Sidebar + Main layout for guide --- */
.guide-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 3rem;
  padding: 2rem 0 4rem;
}
.guide-sidebar {
  position: sticky;
  top: calc(var(--nav-h) + 1.5rem);
  align-self: start;
  max-height: calc(100vh - var(--nav-h) - 3rem);
  overflow-y: auto;
  border-right: 1px solid var(--hairline);
  padding-right: 1.5rem;
}
.guide-sidebar ul { list-style: none; padding-left: 0; }
.guide-sidebar li { margin-bottom: 0.15rem; }
.guide-sidebar a {
  display: block;
  font-size: 0.82rem;
  color: var(--mid);
  text-decoration: none;
  padding: 0.2rem 0;
  border-left: 2px solid transparent;
  padding-left: 0.6rem;
}
.guide-sidebar a:hover { color: var(--ink); border-left-color: var(--ink); }
.guide-sidebar .toc-section {
  font-weight: 700;
  color: var(--ink);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: 1rem;
  margin-bottom: 0.3rem;
  padding-left: 0.6rem;
}

/* --- Tables --- */
table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border: 1px solid var(--faint);
  border-radius: 7px;
  overflow: hidden;
  margin-bottom: 1.5rem;
  font-size: 0.88rem;
}
th, td {
  text-align: left;
  padding: 0.55rem 0.75rem;
  border-bottom: 1px solid var(--faint);
  vertical-align: top;
}
th {
  font-weight: 700;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--mid);
  border-bottom: 2px solid var(--ink);
  background: var(--paper);
}
tr:hover { background: var(--wash); }

/* --- Toolbar icon cells --- */
.tb-icon {
  width: 28px;
  padding: 0.3rem 0.2rem !important;
}
.tb-icon svg {
  display: block;
  width: 24px;
  height: 24px;
  min-width: 24px;
  min-height: 24px;
  fill: var(--ink);
}
.tb-icon .material-symbols-outlined {
  font-size: 24px;
  line-height: 1;
  color: var(--ink);
}

/* --- Action Menu rows --- */
.action-row { margin-bottom: 1.5rem; }
.action-row h4 { margin-bottom: 0.4rem; }
.action-row__items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.action-item {
  background: var(--wash);
  border: 1px solid var(--hairline);
  border-radius: 7px;
  padding: 0.35rem 0.7rem;
  font-size: 0.82rem;
  white-space: nowrap;
}

/* --- Settings Section --- */
.settings-section { margin-bottom: 3rem; }
.settings-section > h3 { border-bottom: 1px solid var(--hairline); padding-bottom: 0.3rem; }

.setting-item {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 0.5rem;
  padding: 0.6rem 0.8rem;
  border: 1px solid var(--faint);
  border-radius: 7px;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}
.setting-item__name { font-weight: 700; }
.setting-item__desc { color: var(--mid); }
.setting-item__desc .tag {
  display: inline-block;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.7rem;
  padding: 0px 5px;
  border-radius: 2px;
  font-family: var(--font-mono);
  margin-right: 0.3rem;
  vertical-align: 1px;
}

/* --- Changelog --- */
.changelog-version {
  margin-bottom: 2rem;
  border: 1px solid var(--hairline);
  border-radius: 7px;
  padding: 1.4rem 1.6rem;
}
.changelog-version h3 { font-size: 1.3rem; margin-top: 0; border-bottom: none; padding-bottom: 0; }
.changelog-version h4 { font-size: 0.95rem; color: var(--mid); margin-top: 1rem; }

/* --- Cards (download, bugs) --- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}
.card {
  border: 1px solid var(--ink);
  border-radius: 7px;
  padding: 1.8rem;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: background 0.15s, border-width 0.1s;
}
.card:hover { background: var(--wash); border-width: 2px; }
.card h3 { margin-top: 0; font-size: 1.1rem; }
.card p { font-size: 0.9rem; margin-bottom: 0; }

/* --- Architecture diagram (text) --- */
.arch-diagram {
  background: var(--wash);
  border: 1px solid var(--ink);
  border-radius: 7px;
  padding: 1.5rem 2rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
  overflow-x: auto;
  margin: 1.5rem 0;
  white-space: pre;
}

/* --- Bug report template --- */
.report-template {
  background: var(--wash);
  border: 1px solid var(--hairline);
  border-radius: 7px;
  padding: 1.5rem;
  margin: 1rem 0 1.5rem;
  font-size: 0.9rem;
}
.report-template dt { font-weight: 700; margin-top: 0.8rem; }
.report-template dt:first-child { margin-top: 0; }
.report-template dd { color: var(--mid); margin-left: 0; }

/* --- Footer --- */
.site-footer {
  border-top: 3px solid var(--ink);
  padding: 2rem 0;
  text-align: center;
  font-size: 0.82rem;
  color: var(--mid);
}
.site-footer a { color: var(--ink); }

/* --- Table scroll wrapper (for mobile) --- */
.table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-bottom: 1.5rem;
}
.table-wrap table { margin-bottom: 0; }

/* --- Mobile --- */
@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .site-nav__links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--ink);
    flex-direction: column;
    padding: 1rem 1.5rem;
    gap: 0.8rem;
    border-bottom: 3px solid var(--ink);
  }
  .site-nav__links.open { display: flex; }
  .hero h1 { font-size: 2.2rem; }
  .features__grid { grid-template-columns: repeat(2, 1fr); }
  .guide-layout { grid-template-columns: 1fr; }
  .guide-sidebar {
    position: static;
    border-right: none;
    border-bottom: 1px solid var(--hairline);
    padding-right: 0;
    padding-bottom: 1rem;
    margin-bottom: 1.5rem;
    max-height: none;
  }
  .setting-item { grid-template-columns: 1fr; }
  .gallery__grid { grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); }
  .action-item { white-space: normal; }
  .device-img { width: 240px; }
  th, td { padding: 0.4rem 0.5rem; }
  table { font-size: 0.84rem; }
  .arch-diagram { font-size: 0.72rem; padding: 1rem; }
  .container { padding: 0 1rem; }
  .card-grid { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
  .hero h1 { font-size: 1.8rem; }
  .hero { padding: 3rem 1rem 2.5rem; }
  .features__grid { grid-template-columns: 1fr; }
  table { font-size: 0.78rem; }
  th, td { padding: 0.35rem 0.4rem; }
  .tb-icon { width: 24px; padding: 0.2rem 0.1rem !important; }
  .tb-icon svg { width: 20px; height: 20px; min-width: 20px; min-height: 20px; }
  .tb-icon .material-symbols-outlined { font-size: 20px; }
  .device-img { width: 200px; }
  .gallery__grid { grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); }
}