/* ============================================================
   Lettera — landing page styles
   Design tokens extracted from the Sketch source.
   ============================================================ */

:root {
  --bg:        #ffffff;
  --surface:   #f1f4f6;   /* light grey section background */
  --card:      #ffffff;
  --ink:       #242629;   /* headings */
  --ink-soft:  #444444;   /* document/mockup text */
  --muted:     #718aa2;   /* section subtitles */
  --muted-2:   #7e94aa;   /* card body text */
  --line:      #e4eaf0;
  --accent:    #226cf7;   /* primary blue */
  --accent-d:  #1b59d6;
  --hl-green:  #dbfdae;
  --hl-purple: #f8dcfd;
  --footer-bg: #1f2227;   /* dark footer (inferred) */

  --radius-lg: 32px;
  --radius-md: 18px;
  --radius-sm: 12px;

  --shadow-card: 0 1px 2px rgba(36,38,41,.04), 0 12px 32px rgba(36,38,41,.06);
  --shadow-float: 0 30px 80px rgba(36,38,41,.16);

  --container: 1160px;
  --ease: cubic-bezier(.22,.61,.36,1);

  --font: "Plus Jakarta Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;   /* guard against any incidental horizontal scroll */
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}
.container--narrow { max-width: 760px; }

/* ============================================================
   Buttons
   ============================================================ */
.btn {
  --pad-y: 13px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font);
  font-weight: 600;
  font-size: 1rem;
  line-height: 1;
  padding: var(--pad-y) 26px;
  border: 0;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: transform .15s var(--ease), background-color .15s var(--ease), box-shadow .15s var(--ease);
  white-space: nowrap;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 6px 18px rgba(34,108,247,.28);
}
.btn-primary:hover { background: var(--accent-d); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-sm { --pad-y: 10px; padding-inline: 20px; font-size: .95rem; }
.btn-lg { --pad-y: 16px; padding-inline: 34px; font-size: 1.25rem; }

/* ============================================================
   Header
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.82);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s var(--ease), box-shadow .25s var(--ease);
}
.site-header.scrolled {
  border-color: var(--line);
  box-shadow: 0 4px 20px rgba(36,38,41,.04);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand-icon { width: 30px; height: 30px; border-radius: 8px; }
.brand-name { font-weight: 800; font-size: 1.25rem; letter-spacing: -.02em; }
.nav { display: flex; gap: 30px; }
.nav a {
  font-weight: 600;
  font-size: .98rem;
  color: var(--muted);
  transition: color .15s var(--ease);
}
.nav a:hover { color: var(--ink); }
.header-actions { display: flex; align-items: center; gap: 12px; }

/* hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px; height: 42px;
  background: transparent;
  border: 0;
  cursor: pointer;
  padding: 10px;
}
.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  border-radius: 2px;
  transition: transform .25s var(--ease), opacity .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 12px 24px 22px;
  border-top: 1px solid var(--line);
  background: #fff;
}
.mobile-menu a {
  font-weight: 600;
  color: var(--ink);
  padding: 12px 4px;
  border-radius: 10px;
}
.mobile-menu a.btn { color: #fff; margin-top: 8px; justify-content: center; }

/* ============================================================
   Hero
   ============================================================ */
.hero { padding: 96px 0 40px; text-align: center; overflow: hidden; }
.hero-inner { display: flex; flex-direction: column; align-items: center; }
.hero-title {
  font-size: clamp(3rem, 8vw, 4.75rem);
  font-weight: 700;
  color: #000;
  letter-spacing: -.03em;
  line-height: 1;
  margin: 0;
  position: relative;
}
/* the app icon is woven into the wordmark, overlapping the final "a" */
.hero-wordmark {
  position: relative;
  display: inline-block;
  padding-right: .95em;            /* room for the overhanging icon */
}
/* the final "a" is kept for screen readers but rendered invisible —
   the app icon stands in for it, exactly as in the source design */
.ghost-a { position: relative; color: transparent; }
.hero-mark {
  position: absolute;
  display: block;
  z-index: -1;
  left: -1.6em;
  bottom: -1.6em;                   /* base just below the text baseline */
  max-width: none;                 /* override the global img max-width */
  transform: rotate(13deg);
  pointer-events: none;
  user-select: none;
}
.hero-tagline {
  margin-top: 16px;
  font-size: clamp(1.15rem, 3.4vw, 1.6rem);
  font-weight: 500;
  color: rgba(113, 138, 162, .9);
}
.hero .btn { margin-top: 30px; }
/* the screenshot is a transparent PNG with the window + its own shadow baked in,
   so it needs no frame, radius, or box-shadow of its own */
.hero-shot {
  position: relative;
  margin-top: 24px;
  width: 100%;
  max-width: 1080px;
  margin-inline: auto;
}
.hero-shot img { width: 100%; display: block; }
/* SVG overlay: colored state diagram + blue bullets, scales 1:1 with the image */
.hero-shot-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}
/* fade the bottom of the window into the page, as in the design */
.hero-shot::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 34%;
  background: linear-gradient(to bottom, rgba(255,255,255,0), #fff 72%);
  pointer-events: none;
}

/* ============================================================
   Section scaffolding
   ============================================================ */
.section { padding: 84px 0; }
.section--alt { background: var(--surface); }
.section-head { text-align: center; max-width: 760px; margin: 0 auto 48px; }
.section-head h2 {
  font-size: clamp(2rem, 5vw, 2.875rem);
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--ink);
}
.section-head p {
  margin-top: 14px;
  font-size: clamp(1.05rem, 2.6vw, 1.5rem);
  font-weight: 500;
  color: var(--muted);
}

/* ============================================================
   Section 1 — dual use showcase cards
   ============================================================ */
.dual-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px;
}
.showcase-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 40px 40px 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.showcase-text h3 { font-size: 1.875rem; font-weight: 700; letter-spacing: -.02em; }
.showcase-text p {
  margin-top: 12px;
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--muted-2);
  max-width: 36ch;
}
.showcase-visual {
  position: relative;
  margin-top: 30px;
  height: 330px;            /* masks the mockup to a fixed window, as in the design */
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}
/* bottom fade so mockups dissolve into the card, as in the design */
.showcase-visual::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 150px;
  background: linear-gradient(to bottom, rgba(241,244,246,0), var(--surface));
  pointer-events: none;
}
.showcase-visual--image img {
  width: 80%;
  align-self: flex-start;
  border-radius: 16px 16px 0 0;
  box-shadow: 0 20px 50px rgba(36,38,41,.14);
}

/* Rococo document mock */
.doc-mock {
  width: 100%;
  max-width: 420px;
  background: #fff;
  border-radius: 16px 16px 0 0;
  box-shadow: 0 20px 50px rgba(36,38,41,.14);
  overflow: hidden;
  text-align: left;
}
.win-dots { display: flex; gap: 7px; padding: 15px 16px 4px; }
.win-dots i { width: 11px; height: 11px; border-radius: 50%; background: #e0e0e0; }
.win-dots i:nth-child(1) { background: #ff5f57; }
.win-dots i:nth-child(2) { background: #febc2e; }
.win-dots i:nth-child(3) { background: #28c840; }
.doc-body { padding: 14px 26px 30px; }
.doc-title { font-size: 1.3rem; font-weight: 700; color: var(--ink-soft); margin-bottom: 12px; }
.doc-para { font-size: .92rem; line-height: 1.65; color: var(--ink-soft); margin-bottom: 10px; }
.footref { color: var(--accent); font-weight: 600; }
mark.hl-green  { background: var(--hl-green);  color: inherit; padding: 1px 2px; border-radius: 3px; }
mark.hl-purple { background: var(--hl-purple); color: inherit; padding: 1px 2px; border-radius: 3px; }

/* ============================================================
   Section 2 — bento grid
   ============================================================ */
.bento {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
  grid-auto-rows: minmax(0, auto);
  gap: 22px;
  max-width: 940px;
  margin-inline: auto;
  grid-template-areas:
    "recap  check"
    "small  table"
    "small  table";
}
.bento-card {
  background: var(--card);
  border-radius: var(--radius-md);
  padding: 26px 28px;
  box-shadow: var(--shadow-card);
  min-width: 0;   /* allow grid items to shrink below their content size */
}
.bento-recap { grid-area: recap; }
.bento-check { grid-area: check; }
.bento-table { grid-area: table; }
/* the three small cards live in the "small" column, stacked */
.bento-code, .bento-math, .bento-attach { grid-column: 1; }

/* Meeting recap */
.recap-title { font-size: 1.6rem; font-weight: 700; color: var(--ink-soft); margin-bottom: 14px; }
.recap-body { font-size: 1.05rem; line-height: 1.6; color: var(--ink-soft); }
.recap-body em { font-style: italic; }
.recap-links { margin-top: 16px; font-size: 1.05rem; color: var(--ink-soft); }
.recap-links a { color: var(--accent); font-weight: 600; margin-left: 8px; }
.recap-links a:hover { text-decoration: underline; }
.caret {
  display: inline-block;
  width: 2px; height: 1.05em;
  background: #3d69a7;
  margin-left: 1px;
  transform: translateY(2px);
  animation: blink 1.05s steps(2, start) infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* Checklist */
.checklist { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 16px; }
.checklist li {
  display: flex; align-items: center; gap: 12px;
  font-size: 1.05rem; color: var(--ink-soft);
}
.checklist .box {
  flex: 0 0 auto;
  width: 22px; height: 22px;
  border: 2px solid #c7d2dd;
  border-radius: 6px;
  display: grid; place-items: center;
  font-size: .8rem; color: transparent;
}
.checklist .done .box { background: var(--accent); border-color: var(--accent); color: #fff; }
.checklist .done { }
.checklist .dim { color: var(--muted-2); text-decoration: line-through; }
.checklist .dim .box { background: #b9c6d3; border-color: #b9c6d3; }

/* Code */
.bento-code pre {
  margin: 0; font-family: var(--mono); font-size: 1.02rem;
  background: #f3f5f7; border-radius: 10px; padding: 18px 20px;
  overflow-x: auto; color: var(--ink-soft);
}
.tok-fn  { color: #6f42c1; }
.tok-str { color: #1d7d3f; }

/* Math */
.bento-math { display: flex; flex-direction: column; justify-content: center; }
.math-label { font-size: 1.02rem; color: var(--ink-soft); margin-bottom: 10px; }
.math-expr {
  font-family: var(--mono); font-size: 1.45rem; color: var(--ink-soft);
  display: flex; align-items: center; gap: 2px;
}
.math-expr .paren { font-size: 1.9rem; font-weight: 300; }
.math-expr sup { font-size: .62em; }
.frac {
  display: inline-flex; flex-direction: column; align-items: center;
  font-size: .62em; line-height: 1; margin: 0 4px; vertical-align: middle;
}
.frac .num { border-bottom: 1.5px solid currentColor; padding: 0 4px 2px; }
.frac .den { padding: 2px 4px 0; }

/* Attachment */
.bento-attach { display: flex; align-items: center; }
.file-chip { display: flex; align-items: center; gap: 14px; }
.file-badge {
  flex: 0 0 auto;
  min-width: 46px; height: 32px;
  padding: 0 10px;
  border-radius: 7px;
  background: #f3f5f7; color: #8a8a8a;
  display: grid; place-items: center;
  font-size: .78rem; font-weight: 700; letter-spacing: .04em;
}
.file-meta { display: flex; flex-direction: column; gap: 4px; }
.file-name { font-size: 1.05rem; font-weight: 600; color: var(--ink-soft); word-break: break-word; }
.file-sub  { font-size: .9rem; color: #888; }

/* Mac tips table */
.table-title { font-size: 1.4rem; font-weight: 700; color: var(--ink-soft); }
.table-sub { margin: 6px 0 18px; font-size: 1rem; color: var(--ink-soft); }
.tips-table { width: 100%; border-collapse: separate; border-spacing: 0; table-layout: fixed; }
.tips-table th, .tips-table td {
  text-align: left; padding: 12px 12px;
  font-size: 1.02rem; color: var(--ink-soft);
}
.tips-table th { font-weight: 700; }
/* zebra striping: header + alternating rows get the light-grey fill (matches design) */
.tips-table thead th { background: #f3f5f7; }
.tips-table thead th:first-child { border-radius: 8px 0 0 8px; }
.tips-table thead th:last-child  { border-radius: 0 8px 8px 0; }
.tips-table tbody tr:nth-child(even) td { background: #f3f5f7; }
.tips-table tbody tr:nth-child(even) td:first-child { border-radius: 8px 0 0 8px; }
.tips-table tbody tr:nth-child(even) td:last-child  { border-radius: 0 8px 8px 0; }
.tips-table td:last-child, .tips-table th:last-child { text-align: right; }
kbd {
  display: inline-block;
  font-family: var(--font);
  font-size: .8rem; font-weight: 600;
  padding: 3px 8px; margin-left: 4px;
  background: #f1f4f6; border: 1px solid var(--line);
  border-radius: 6px; color: #56616e;
}

/* ============================================================
   Section 3 — Know your document
   ============================================================ */
.know-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 30px;
  overflow: hidden;
  max-width: 940px;
  margin-inline: auto;
  align-items: stretch;
}
.know-visual {
  position: relative;
  height: 440px;            /* masks the tall TOC mockup, as in the design */
  overflow: hidden;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 52px 0 0 52px;
}
.know-visual img {
  width: 84%;
  align-self: flex-start;
  border-radius: 0 35px 0 0;   /* only the top-right corner is rounded, per spec */
  box-shadow: 0 20px 50px rgba(36,38,41,.14);
}
.know-visual::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 130px;
  background: linear-gradient(to bottom, rgba(241,244,246,0), var(--surface));
  pointer-events: none;
}
.know-text { padding: 56px 56px 56px 0; display: flex; flex-direction: column; justify-content: center; gap: 38px; }
.know-block h3 { font-size: 1.875rem; font-weight: 700; color: var(--ink); }
.know-block p { margin-top: 10px; font-size: 1.125rem; font-weight: 500; color: var(--muted-2); }

/* ============================================================
   Section 4 — And more
   ============================================================ */
.more-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 56px;
  max-width: 940px;
  margin-inline: auto;
}
.more-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 44px 64px;
  position: relative;
}
/* vertical divider between the two columns, as in the design */
.more-grid::before {
  content: "";
  position: absolute;
  top: 0; bottom: 0; left: 50%;
  width: 1px;
  background: #dde4ec;
  transform: translateX(-50%);
}
.more-item h3 { font-size: 1.875rem; font-weight: 700; color: var(--ink); }
.more-item p { margin-top: 10px; font-size: 1.125rem; font-weight: 500; color: var(--muted-2); }
.center-cta { text-align: center; margin-top: 48px; }

/* ============================================================
   Section 5 — FAQ
   ============================================================ */
.faq { display: flex; flex-direction: column; }
.faq-item { border-bottom: 1px solid var(--line); }
.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 26px 44px 26px 0;
  position: relative;
  font-size: clamp(1.3rem, 3.2vw, 1.875rem);
  font-weight: 600;
  color: var(--ink);
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "";
  position: absolute;
  right: 4px; top: 50%;
  width: 12px; height: 12px;
  border-right: 2.5px solid var(--muted);
  border-bottom: 2.5px solid var(--muted);
  transform: translateY(-65%) rotate(45deg);
  transition: transform .25s var(--ease);
}
.faq-item[open] summary::after { transform: translateY(-35%) rotate(-135deg); }
.faq-answer { padding: 0 44px 28px 0; }
.faq-answer p { font-size: 1.125rem; font-weight: 500; color: var(--muted-2); }
.faq-answer a { color: var(--accent); font-weight: 600; }
.faq-answer a:hover { text-decoration: underline; }

/* ============================================================
   Section 6 — Newsletter
   ============================================================ */
.newsletter .section-head { margin-bottom: 32px; }
.signup {
  display: flex;
  gap: 12px;
  max-width: 520px;
  margin-inline: auto;
}
.signup input {
  flex: 1;
  font-family: var(--font);
  font-size: 1.125rem;
  padding: 15px 20px;
  border: 1.5px solid var(--line);
  border-radius: var(--radius-sm);
  color: var(--ink);
  background: #fff;
  transition: border-color .15s var(--ease), box-shadow .15s var(--ease);
}
.signup input::placeholder { color: var(--muted); }
.signup input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(34,108,247,.12);
}
.signup .btn { flex: 0 0 auto; font-size: 1.125rem; }
.signup-msg {
  text-align: center;
  margin-top: 16px;
  font-weight: 600;
  color: #1d7d3f;
  min-height: 1.4em;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  background: var(--footer-bg);
  color: #fff;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  margin-top: 0;
  padding: 64px 0 36px;
}
.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 1fr) minmax(0, 1fr);
  gap: 40px;
}
.footer-brand { display: flex; align-items: flex-start; gap: 14px; }
.footer-icon { width: 46px; height: 46px; border-radius: 11px; }
.footer-brand p { font-size: 1.25rem; font-weight: 600; line-height: 1.4; color: rgba(255,255,255,.92); }
.footer-brand strong { font-weight: 700; }
.footer-col h4 { font-size: 1.25rem; font-weight: 600; margin-bottom: 18px; }
.footer-col a {
  display: block;
  font-size: 1rem;
  font-weight: 500;
  color: rgba(255,255,255,.66);
  padding: 7px 0;
  transition: color .15s var(--ease);
}
.footer-col a:hover { color: #fff; }
.footer-bottom {
  margin-top: 48px;
  padding-top: 26px;
  border-top: 1px solid rgba(255,255,255,.12);
}
.footer-bottom p { font-size: 1rem; color: rgba(255,255,255,.55); }

/* ============================================================
   Reveal on scroll
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 900px) {
  .section { padding: 64px 0; }

  .bento {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "recap"
      "check"
      "code"
      "math"
      "attach"
      "table";
    max-width: 520px;
  }
  .bento-code  { grid-area: code; }
  .bento-math  { grid-area: math; }
  .bento-attach{ grid-area: attach; }

  .know-card { grid-template-columns: minmax(0, 1fr); }
  .know-visual { height: 360px; padding: 44px 44px 0; }
  .know-visual img { width: 66%; border-radius: 16px 16px 0 0; }
  .know-text { padding: 8px 44px 48px; }

  .more-grid { gap: 36px 40px; }
}

@media (max-width: 760px) {
  .nav { display: none; }
  .header-actions .btn-sm { display: none; }
  .nav-toggle { display: flex; }

  .dual-grid { grid-template-columns: minmax(0, 1fr); }
  .showcase-card { padding: 32px 28px 0; }
  .showcase-visual { height: 300px; }

  .more-card { padding: 36px 28px; }
  .more-grid { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .more-grid::before { display: none; }   /* no divider when stacked */

  .br-desktop { display: none; }
}

@media (max-width: 560px) {
  .container { padding-inline: 18px; }
  .hero { padding: 48px 0 24px; }
  .hero-shot { margin-top: 40px; }

  .signup { flex-direction: column; }
  .signup .btn { width: 100%; }

  .footer-inner { grid-template-columns: minmax(0, 1fr); gap: 36px; }

  .faq-item summary { font-size: 1.12rem; }

  .bento-card { padding: 22px 20px; }
  .tips-table th, .tips-table td { font-size: .86rem; padding: 10px 2px; }
  .tips-table td:last-child { line-height: 2.1; }   /* let keys wrap neatly */
  kbd { font-size: .68rem; padding: 2px 5px; margin-left: 3px; }

  .math-expr { font-size: 1.25rem; }
}

/* When the mobile menu is open, neutralise the [hidden] attr */
.mobile-menu:not([hidden]) { display: flex; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .caret { animation: none; }
  html { scroll-behavior: auto; }
}