/* Korasa landing — navy desk, grid paper, ink. */
:root {
  --navy: #0b1d3f;
  --navy-2: #102a57;
  --ink: #1f1d1a;
  --ink-soft: #57524a;
  --paper: #fbfaf6;
  --paper-2: #f3f0e8;
  --line: #e4dfd3;
  --grid: rgba(120, 155, 185, 0.22);
  --accent: #2f4fb0;
  --accent-light: #9db8ff;
  --radius: 10px;
  --serif: "Instrument Serif", Georgia, serif;
  --sans: "Hanken Grotesk", ui-sans-serif, system-ui, sans-serif;
  --hand: "Caveat", cursive;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font: 17px/1.6 var(--sans);
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
code {
  font: 0.86em ui-monospace, "JetBrains Mono", monospace;
  background: rgba(60, 50, 30, 0.07);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}
h1, h2 {
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -0.01em;
  line-height: 1.02;
  margin: 0;
}
h1 { font-size: clamp(2.8rem, 6.4vw, 5.2rem); }
h2 { font-size: clamp(2.2rem, 4.6vw, 3.6rem); margin-bottom: 1.2rem; }
h1 em, h2 em { font-style: italic; }
.wrap { width: min(1180px, 100% - 32px); margin-inline: auto; }

.eyebrow {
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--accent-light);
  margin: 0 0 1rem;
}
.eyebrow-ink { color: var(--accent); }
.lede { font-size: 1.15rem; max-width: 34em; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.8rem 1.3rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.98rem;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn:focus-visible { outline: 3px solid var(--accent-light); outline-offset: 2px; }
.btn svg { width: 1.15em; height: 1.15em; fill: none; stroke: currentColor; stroke-width: 2.2; stroke-linecap: round; stroke-linejoin: round; }
.btn-primary { background: var(--paper); color: var(--navy); box-shadow: 0 10px 30px -12px rgba(0, 0, 0, 0.6); }
.btn-ghost { color: var(--paper); border-color: rgba(255, 255, 255, 0.3); }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.08); }
.btn-small { padding: 0.45rem 1rem; font-size: 0.9rem; background: var(--navy); color: #fff; }
.btn[aria-disabled="true"] { opacity: 0.5; pointer-events: none; }

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(251, 250, 246, 0.86);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; gap: 2rem; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 0.55rem; text-decoration: none; font: 1.6rem var(--serif); }
.brand img { width: 36px; height: 36px; }
.nav nav { display: flex; gap: 1.6rem; margin-left: auto; font-size: 0.95rem; }
.nav nav a { text-decoration: none; color: var(--ink-soft); }
.nav nav a:hover { color: var(--ink); }

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  color: #eef1f8;
  background-color: var(--navy);
  background-image:
    radial-gradient(1200px 500px at 85% -10%, rgba(80, 120, 220, 0.35), transparent 60%),
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: auto, 32px 32px, 32px 32px;
  padding: clamp(4rem, 9vw, 7rem) 0 clamp(4rem, 8vw, 6rem);
}
.hero-grid { display: grid; grid-template-columns: 1fr 1.15fr; gap: 3rem; align-items: center; }
.hero h1 em { color: #c9d6f5; }
.hero .lede { color: #c5cddd; margin: 1.6rem 0 2.2rem; }
.cta { display: flex; gap: 0.8rem; flex-wrap: wrap; }
.meta { margin-top: 1.2rem; font-size: 0.9rem; color: #93a0bb; }

.hero-visual { position: relative; animation: rise 0.9s cubic-bezier(0.2, 0.7, 0.2, 1) both 0.1s; }
.window {
  margin: 0;
  position: relative;
  z-index: 1;
  border-radius: 12px;
  overflow: hidden;
  background: #fff;
  box-shadow: 0 40px 80px -30px rgba(0, 0, 0, 0.75), 0 0 0 1px rgba(255, 255, 255, 0.08);
  transform: perspective(1600px) rotateY(-9deg) rotateX(3deg);
  transform-origin: left center;
}
.window-bar { height: 26px; background: #ebe7de; display: flex; align-items: center; gap: 6px; padding-left: 11px; }
.window-bar i { width: 10px; height: 10px; border-radius: 50%; background: #cfc8bb; }
.sheet-logo {
  position: absolute;
  width: 46%;
  right: -9%;
  bottom: -24%;
  transform: rotate(9deg);
  z-index: 2;
  filter: drop-shadow(0 20px 30px rgba(0, 0, 0, 0.45));
}
.scribble {
  position: absolute;
  left: -2%;
  bottom: -14%;
  font: 1.7rem var(--hand);
  color: #c9d6f5;
  transform: rotate(-4deg);
}
@keyframes rise { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: none; } }

/* Sections */
.section { padding: clamp(4.5rem, 9vw, 7.5rem) 0; }
.section-lede { color: var(--ink-soft); margin: -0.4rem 0 2.4rem; }

.features {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.features article {
  padding: 2rem 1.8rem 2.2rem;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(var(--grid) 1px, transparent 1px) 0 0 / 100% 28px;
  background-color: #fff;
}
.features article:nth-child(2n) { background-color: var(--paper); }
.features svg { width: 30px; height: 30px; fill: none; stroke: var(--accent); stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.features h3 { font-size: 1.15rem; margin: 1rem 0 0.4rem; }
.features p { margin: 0; color: var(--ink-soft); font-size: 0.98rem; }

.showcase { background: var(--paper-2); }
.showcase-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 2.4rem; }
.shot { margin: 0; }
.shot img {
  border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(40, 30, 10, 0.08), 0 24px 48px -24px rgba(40, 30, 10, 0.4);
  border: 1px solid var(--line);
}
.shot figcaption { margin-top: 1.1rem; color: var(--ink-soft); font-size: 0.98rem; max-width: 36em; }
.shot figcaption b { color: var(--ink); }

/* Privacy */
.private {
  background: var(--navy);
  color: #e7ebf4;
  padding: clamp(4.5rem, 9vw, 7rem) 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 32px 32px;
}
.private-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.private h2 em { color: #c9d6f5; }
.private .lede { color: #b7c1d6; }
.checks { list-style: none; margin: 0; padding: 0; display: grid; gap: 1.1rem; }
.checks li {
  position: relative;
  padding: 1rem 1.2rem 1rem 3rem;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  color: #c5cddd;
}
.checks li::before {
  content: "";
  position: absolute;
  left: 1.1rem;
  top: 1.25rem;
  width: 0.9rem;
  height: 0.5rem;
  border-left: 2px solid var(--accent-light);
  border-bottom: 2px solid var(--accent-light);
  transform: rotate(-45deg);
}
.checks b { color: #fff; font-weight: 600; }

/* Downloads */
.downloads { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.2rem; }
.dl {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 2rem 1.6rem 1.8rem;
  background: #fff;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.dl.is-current { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(47, 79, 176, 0.12); }
.dl.is-current::after {
  content: "Your system";
  position: absolute;
  top: 1rem;
  right: 1rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
}
.dl svg { width: 34px; height: 34px; fill: none; stroke: var(--navy); stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.dl svg .fill { fill: var(--navy); stroke: none; }
.dl h3 { font: 2rem var(--serif); margin: 0.9rem 0 0.1rem; }
.dl p { margin: 0 0 1.4rem; color: var(--ink-soft); font-size: 0.95rem; }
.dl .btn-primary { background: var(--navy); color: #fff; box-shadow: none; }
.dl .btn-primary:hover { background: var(--navy-2); }
.btn-ghost-ink { border-color: var(--line); color: var(--navy); background: transparent; }
.btn-ghost-ink:hover { background: var(--paper-2); }
.dl-pair { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-top: auto; }
.dl > .btn { margin-top: auto; }

.install-notes { margin-top: 1.6rem; border: 1px solid var(--line); border-radius: 14px; background: var(--paper-2); }
.install-notes summary { cursor: pointer; padding: 1.1rem 1.4rem; font-weight: 600; }
.notes-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.6rem; padding: 0 1.4rem 1.4rem; }
.notes-grid h4 { margin: 0 0 0.3rem; }
.notes-grid p { margin: 0; color: var(--ink-soft); font-size: 0.94rem; }

/* FAQ */
.faq { border-top: 1px solid var(--line); }
.faq-grid { display: grid; grid-template-columns: 1fr 1.6fr; gap: 3rem; }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary {
  cursor: pointer;
  list-style: none;
  padding: 1.15rem 2rem 1.15rem 0;
  font-weight: 600;
  position: relative;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; right: 0.3rem; font-weight: 400; font-size: 1.3rem; top: 0.9rem; color: var(--ink-soft); }
.faq-list details[open] summary::after { content: "–"; }
.faq-list p { margin: 0 0 1.2rem; color: var(--ink-soft); }

/* Footer */
.footer { border-top: 1px solid var(--line); padding: 2rem 0; font-size: 0.92rem; color: var(--ink-soft); }
.footer-inner { display: flex; align-items: center; gap: 1.5rem; flex-wrap: wrap; justify-content: space-between; }
.brand-small { font-size: 1.3rem; color: var(--ink); }
.brand-small img { width: 26px; height: 26px; }

/* Responsive */
@media (max-width: 960px) {
  .hero-grid, .private-grid, .faq-grid { grid-template-columns: 1fr; }
  .hero-visual { margin: 1rem 4% 4rem 0; }
  .features { grid-template-columns: repeat(2, 1fr); }
  .downloads, .notes-grid, .showcase-grid { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  .nav nav { display: none; }
  .nav-inner .btn-small { margin-left: auto; }
  .features { grid-template-columns: 1fr; }
  .window { transform: none; }
  .scribble { display: none; }
  .cta .btn { flex: 1 1 100%; }
}
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}