/* md-reader landing — lean technical, Apple-leaning palette */

:root {
  --bg: #0d0d10;
  --bg-1: #16161a;
  --bg-2: #1c1c21;
  --fg: #f5f5f7;
  --fg-2: #c7c7cc;
  --muted: #8d8d93;
  --border: #2a2a30;
  --accent: #0a84ff;
  --accent-soft: rgba(10, 132, 255, .14);
  --max: 1140px;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #ffffff;
    --bg-1: #f8f8fa;
    --bg-2: #ffffff;
    --fg: #18181b;
    --fg-2: #3f3f46;
    --muted: #71717a;
    --border: #e4e4e7;
    --accent: #007aff;
    --accent-soft: rgba(0, 122, 255, .12);
  }
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI Variable Text", "Segoe UI", Inter, system-ui, sans-serif;
  font-feature-settings: "kern", "liga", "calt", "ss01";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-size: 16px;
  line-height: 1.55;
}

a { color: inherit; text-decoration: none; }
code {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: .9em;
  background: var(--bg-1);
  border: 1px solid var(--border);
  padding: .1em .35em;
  border-radius: 4px;
}

/* Top bar */
.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--border);
}
.topbar-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  font-weight: 600;
  font-size: 15px;
}
.logo {
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--accent);
  color: white;
  border-radius: 7px;
  font-weight: 700;
  font-size: 15px;
}
.topnav {
  display: flex;
  gap: 1.4rem;
  font-size: 14px;
  color: var(--fg-2);
  align-items: center;
}
.topnav a:hover { color: var(--fg); }
.topnav .gh {
  background: var(--bg-1);
  border: 1px solid var(--border);
  padding: 6px 12px;
  border-radius: 7px;
  font-size: 13px;
}
.topnav .gh:hover { background: var(--accent-soft); border-color: var(--accent); }

/* Hero */
.hero {
  max-width: var(--max);
  margin: 0 auto;
  padding: 6rem 24px 4rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
}
@media (min-width: 980px) {
  .hero { grid-template-columns: 1.1fr 1fr; gap: 4rem; align-items: center; }
}
.hero-inner { max-width: 600px; }
.kicker {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 1.4rem;
  padding: 5px 11px;
  border: 1px solid var(--accent);
  border-radius: 99px;
  background: var(--accent-soft);
}
.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.2rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.04;
  margin: 0 0 1.4rem;
  color: var(--fg);
  text-wrap: balance;
}
.lede {
  font-size: 18px;
  color: var(--fg-2);
  margin: 0 0 2rem;
  max-width: 540px;
  text-wrap: pretty;
}
.cta {
  display: flex;
  gap: .6rem;
  margin-bottom: 1.4rem;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  height: 44px;
  padding: 0 1.2rem;
  border-radius: 9px;
  font-size: 15px;
  font-weight: 500;
  border: 1px solid transparent;
  transition: transform 90ms ease, background 120ms ease, border-color 120ms ease;
}
.btn:active { transform: translateY(1px); }
.btn.primary { background: var(--accent); color: white; }
.btn.primary:hover { background: color-mix(in srgb, var(--accent) 88%, white); }
.btn.ghost { background: transparent; color: var(--fg); border-color: var(--border); }
.btn.ghost:hover { border-color: var(--accent); background: var(--accent-soft); }
.meta {
  font-size: 12px;
  color: var(--muted);
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

/* Hero demo (mock window) */
.hero-demo { perspective: 1200px; }
.window {
  background: var(--bg-1);
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: hidden;
  box-shadow:
    0 30px 80px rgba(0, 0, 0, .35),
    0 8px 24px rgba(0, 0, 0, .15);
  transform: rotateY(-3deg) rotateX(2deg);
  transform-origin: center;
}
.titlebar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 11px 14px;
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  color: var(--muted);
}
.dot { width: 11px; height: 11px; border-radius: 50%; display: inline-block; }
.dot-r { background: #ff5f57; }
.dot-y { background: #febc2e; }
.dot-g { background: #28c840; }
.titlebar .title { margin-left: auto; margin-right: 14px; }

.tabs {
  display: flex;
  background: var(--bg-1);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  height: 30px;
  align-items: stretch;
  padding: 0 8px;
  gap: 1px;
}
.tab {
  display: inline-flex;
  align-items: center;
  padding: 0 .9rem;
  color: var(--muted);
  border-right: 1px solid var(--border);
  position: relative;
}
.tab.active {
  background: var(--bg);
  color: var(--fg);
  font-weight: 500;
}
.tab.active::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: var(--accent);
}
.tab-plus {
  width: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 16px;
}

.window-body {
  display: grid;
  grid-template-columns: 150px 1fr;
  min-height: 320px;
  background: var(--bg);
}
.sidebar {
  background: var(--bg-1);
  border-right: 1px solid var(--border);
  padding: 16px 12px;
  font-size: 11.5px;
}
.sb-label {
  font-size: 9.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: .55rem;
  font-weight: 600;
}
.sb-item {
  padding: 4px 8px;
  color: var(--fg-2);
  border-radius: 4px;
  margin-bottom: 1px;
}
.sb-item.active { background: var(--accent-soft); color: var(--fg); }
.sb-item.indent { padding-left: 1.4rem; color: var(--muted); }
.doc {
  padding: 22px 26px;
  font-size: 13px;
  line-height: 1.55;
  overflow: hidden;
  position: relative;
}
.doc h1 {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 .35em;
  letter-spacing: -0.015em;
}
.doc h2 {
  font-size: 15px;
  font-weight: 600;
  margin: 1.4em 0 .35em;
  border-bottom: 1px solid var(--border);
  padding-bottom: 4px;
}
.doc p { margin: .5em 0; color: var(--fg-2); font-size: 12.5px; }
.doc code { font-size: 11.5px; }
.doc .hr { height: 1px; background: var(--border); margin: 1em 0; padding: 0; }
.typing .caret {
  display: inline-block;
  width: 7px;
  height: 1em;
  background: var(--accent);
  vertical-align: text-bottom;
  margin-left: 2px;
  animation: blink 1.05s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* Section heading */
.section-h {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.018em;
  margin: 0 0 2rem;
  color: var(--fg);
}

/* Features */
.features {
  max-width: var(--max);
  margin: 0 auto;
  padding: 5rem 24px 4rem;
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 14px;
}
.card {
  background: var(--bg-1);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 22px;
  transition: border-color 150ms ease, transform 150ms ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.emoji { font-size: 22px; margin-bottom: .5rem; }
.card h3 { font-size: 15px; font-weight: 600; margin: 0 0 .35rem; }
.card p { font-size: 13.5px; color: var(--fg-2); margin: 0; line-height: 1.55; }

/* Why */
.why {
  background: var(--bg-1);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.why .section-h { max-width: var(--max); margin: 0 auto 2rem; padding: 0 24px; }
.why { padding: 5rem 0; }
.why-grid {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 22px;
}
.why-cell h3 { font-size: 17px; font-weight: 600; margin: 0 0 .5rem; color: var(--fg); }
.why-cell p { font-size: 14px; color: var(--fg-2); margin: 0; max-width: 44ch; }

/* Download */
.download {
  max-width: var(--max);
  margin: 0 auto;
  padding: 5rem 24px;
}
.download-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin-bottom: 1rem;
}
.dl-card {
  display: flex;
  align-items: center;
  background: var(--bg-1);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  transition: border-color 150ms ease, background 150ms ease;
}
.dl-card:hover { border-color: var(--accent); background: var(--accent-soft); }
.dl-os { font-size: 16px; font-weight: 600; }
.dl-info { font-size: 12.5px; color: var(--muted); margin-left: auto; margin-right: 10px; }
.dl-arrow { font-size: 18px; color: var(--accent); }
.download-note { font-size: 13px; color: var(--muted); margin-top: 1rem; }

/* Stack */
.stack {
  background: var(--bg-1);
  border-top: 1px solid var(--border);
  padding: 4rem 0;
}
.stack-inner { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
.stack .section-h { margin-bottom: 1.5rem; }
.stack-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}
.stack-grid > div {
  background: var(--bg);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.stack-grid strong {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--muted);
  font-weight: 600;
}
.stack-grid span { font-size: 14px; }

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}
.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .55rem;
  font-size: 13px;
  color: var(--muted);
}
.footer-inner a { color: var(--fg-2); border-bottom: 1px dotted var(--border); }
.footer-inner a:hover { color: var(--accent); border-color: var(--accent); }
.dot-sep { opacity: .5; }