/* KnightSight — © 2026 KnightSight. All rights reserved. */

:root {
  --navy: #0b1f4d;
  --navy-2: #13306b;
  --blue: #1546ff;
  --cyan: #c8f4fa;
  --cyan-2: #8fe3f5;
  --bg: #f6fafc;
  --card: #ffffff;
  --text: #0e1b33;
  --muted: #5a6880;
  --line: #dde6ef;
  --good: #0f8a4f;
  --warn: #b45309;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(11, 31, 77, 0.06), 0 6px 24px rgba(11, 31, 77, 0.06);
  --light-sq: #eef3f6;
  --dark-sq: #7fa7c9;
  color-scheme: light;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, sans-serif;
}
a { color: var(--blue); }
img { max-width: 100%; display: block; }
h1, h2, h3 { line-height: 1.2; margin: 0 0 0.5em; color: var(--navy); }
p { margin: 0 0 1em; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

/* ---------- header / footer ---------- */

.top {
  position: sticky; top: 0; z-index: 10;
  background: rgba(246, 250, 252, 0.88);
  backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid var(--line);
}
.top .wrap { display: flex; align-items: center; gap: 16px; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--navy); font-weight: 750; font-size: 19px; letter-spacing: -0.01em; }
.brand img { width: 36px; height: 36px; }
.top nav { margin-left: auto; display: flex; gap: 18px; align-items: center; }
.top nav a { color: var(--navy); text-decoration: none; font-weight: 550; font-size: 15px; }
.top nav a.btn { color: #fff; }
@media (max-width: 640px) { .top nav a:not(.btn) { display: none; } }

footer { border-top: 1px solid var(--line); margin-top: 64px; padding: 28px 0 40px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; }
footer a { color: var(--muted); }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 44px; padding: 0 18px; border-radius: 999px;
  border: 1px solid var(--line); background: var(--card); color: var(--navy);
  font: inherit; font-weight: 650; text-decoration: none; cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease;
}
.btn:hover { box-shadow: var(--shadow); }
.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: 0.45; cursor: default; box-shadow: none; transform: none; }
.btn.primary { background: var(--blue); border-color: var(--blue); color: #fff; }
.btn.navy { background: var(--navy); border-color: var(--navy); color: #fff; }
.btn.big { min-height: 54px; padding: 0 26px; font-size: 17px; }
.btn.small { min-height: 36px; padding: 0 14px; font-size: 14px; }

/* ---------- welcome page ---------- */

.hero { padding: 56px 0 24px; text-align: center; }
.hero .logo { width: min(520px, 92%); height: auto; margin: 0 auto 8px; }
.hero h1 { font-size: clamp(30px, 5vw, 48px); letter-spacing: -0.02em; margin-top: 8px; }
.hero .lead { font-size: clamp(17px, 2.2vw, 20px); color: var(--muted); max-width: 640px; margin: 0 auto 28px; }
.hero .cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

section.block { padding: 40px 0 8px; }
section.block > .wrap > h2 { font-size: 28px; letter-spacing: -0.01em; }
.sub { color: var(--muted); margin-top: -4px; }

.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 20px; }
.grid2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; margin-top: 20px; }
@media (max-width: 820px) { .grid3, .grid2 { grid-template-columns: 1fr; } }

.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.card h3 { font-size: 18px; }
.card p:last-child { margin-bottom: 0; }
.step { width: 32px; height: 32px; border-radius: 50%; background: var(--cyan); color: var(--navy); display: grid; place-items: center; font-weight: 800; margin-bottom: 12px; }
.card ul { margin: 0; padding-left: 20px; }
.card li { margin: 4px 0; }
.note { background: #fff8eb; border-color: #f4dfb5; }
.tag { display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: 0.04em; text-transform: uppercase; color: var(--navy-2); background: var(--cyan); border-radius: 999px; padding: 3px 10px; margin-bottom: 10px; }

.legal { max-width: 760px; }
.legal h2 { margin-top: 1.6em; font-size: 22px; }
.legal pre { white-space: pre-wrap; background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 14px; font-size: 13px; }

/* ---------- install guide ---------- */

.guide { max-width: 760px; }
.guide h1 { margin-top: 36px; font-size: clamp(28px, 4.5vw, 40px); letter-spacing: -0.02em; }
.guide .lead { font-size: 18px; color: var(--muted); }
.guide h2 { display: flex; align-items: center; gap: 12px; margin-top: 2em; font-size: 24px; scroll-margin-top: 76px; }
.guide h2 .step { margin: 0; flex: none; }
.guide ol, .guide ul { padding-left: 22px; }
.guide li { margin: 6px 0; }
.guide .card { margin: 16px 0; }
.toc ol { margin: 0; columns: 2; column-gap: 32px; }
@media (max-width: 640px) { .toc ol { columns: 1; } }
.guide code { font: 14px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace; background: #eaf0f5; border-radius: 6px; padding: 1px 6px; }
.code { position: relative; margin: 10px 0; }
.code pre { margin: 0; background: var(--navy); color: #e8f1ff; border-radius: 10px; padding: 14px 92px 14px 16px; white-space: pre-wrap; overflow-wrap: anywhere; }
.code pre code { background: none; padding: 0; color: inherit; font-size: 14px; }
.copy { position: absolute; top: 8px; right: 8px; min-height: 30px; padding: 0 12px; border-radius: 999px; border: 1px solid rgba(255,255,255,0.25); background: rgba(255,255,255,0.1); color: #fff; font: inherit; font-size: 13px; font-weight: 650; cursor: pointer; }
.copy:hover { background: rgba(255,255,255,0.2); }
kbd { font: 13px ui-monospace, Menlo, monospace; border: 1px solid var(--line); border-bottom-width: 2px; border-radius: 6px; padding: 1px 6px; background: var(--card); }
.faq dt { font-weight: 700; color: var(--navy); margin-top: 14px; }
.faq dd { margin: 4px 0 0; color: var(--text); }

/* ---------- welcome: first screen and demo video ---------- */

.hero { min-height: calc(100svh - 60px); display: flex; flex-direction: column; justify-content: center; position: relative; padding-bottom: 72px; }
.scroll-cue { position: absolute; left: 50%; bottom: 20px; transform: translateX(-50%); display: flex; flex-direction: column; align-items: center; gap: 2px; color: var(--muted); font-size: 14px; font-weight: 600; text-decoration: none; }
.scroll-cue span { font-size: 20px; animation: cue 1.8s ease-in-out infinite; }
@keyframes cue { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(5px); } }

.demo { padding: 40px 0 24px; text-align: center; }
.demo .sub { margin-top: 14px; }
.demo-frame { position: relative; display: inline-block; max-width: 100%; border-radius: 22px; overflow: hidden; background: var(--navy); box-shadow: 0 2px 6px rgba(11, 31, 77, 0.1), 0 24px 60px rgba(11, 31, 77, 0.18); }
.demo-frame video { display: block; max-width: 100%; max-height: min(82svh, 720px); width: auto; height: auto; }
.demo-sound { position: absolute; left: 50%; bottom: 16px; transform: translateX(-50%); display: inline-flex; align-items: center; gap: 8px; min-height: 44px; padding: 0 20px; border-radius: 999px; border: 0; background: var(--blue); color: #fff; font: inherit; font-size: 16px; font-weight: 700; cursor: pointer; box-shadow: 0 6px 20px rgba(21, 70, 255, 0.4); white-space: nowrap; }
.demo-sound.on { left: auto; right: 12px; transform: none; min-height: 36px; padding: 0 14px; font-size: 14px; background: rgba(11, 31, 77, 0.72); box-shadow: none; backdrop-filter: blur(6px); }
.demo-frame video { cursor: pointer; }

.js-reveal .reveal { opacity: 0; transform: translateY(32px) scale(0.98); transition: opacity 0.9s ease, transform 0.9s cubic-bezier(0.2, 0.7, 0.2, 1); }
.js-reveal .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .js-reveal .reveal { opacity: 1; transform: none; transition: none; }
  .scroll-cue span { animation: none; }
}
.demo-sound .ico { width: 20px; height: 20px; flex: none; }