/* KTSE LLC website (launch candidate, Option B): deep navy, restrained electric-blue accents. No web fonts or images
   other than real PayLeft screenshots. */
:root {
  --bg: #070b17;
  --bg-2: #0b1222;
  --surface: rgba(255, 255, 255, 0.035);
  --surface-strong: rgba(255, 255, 255, 0.06);
  --line: rgba(255, 255, 255, 0.09);
  --text: #edf1fa;
  --text-soft: #c4cde0;
  --muted: #9aa6bf;
  --electric: #5b86ff;
  --electric-strong: #3d6bff;
  --payleft: #2048c8;
  --payleft-deep: #14358e;
  --radius: 18px;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--electric); text-underline-offset: 0.2em; }
:focus-visible { outline: 3px solid var(--electric); outline-offset: 3px; border-radius: 6px; }

.container { max-width: 72rem; margin: 0 auto; padding: 0 1.5rem; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 1rem; top: 1rem; background: var(--bg); color: var(--text); padding: 0.5rem 0.75rem; z-index: 20; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 10; background: rgba(7, 11, 23, 0.82);
  backdrop-filter: saturate(140%) blur(14px); -webkit-backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid var(--line); }
.site-header .container { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: 0.6rem 2rem; padding-top: 0.95rem; padding-bottom: 0.95rem; }
.wordmark { color: var(--text); text-decoration: none; font-weight: 700; letter-spacing: 0.14em; font-size: 1.02rem; }
.wordmark small { font-weight: 500; letter-spacing: 0.08em; color: var(--muted); margin-left: 0.4rem; font-size: 0.78rem; }
.site-nav ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; align-items: center; gap: 0.25rem 1.6rem; }
.site-nav a { color: var(--text-soft); text-decoration: none; font-size: 0.95rem; font-weight: 500; }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--text); }
.site-nav a[aria-current="page"] { box-shadow: inset 0 -2px 0 var(--electric); padding-bottom: 0.2rem; }
.nav-cta { border: 1px solid var(--line); border-radius: 999px; padding: 0.4rem 0.95rem; background: var(--surface); }

/* Type */
h1, h2, h3 { margin: 0; letter-spacing: -0.025em; color: var(--text); }
h1 { font-size: clamp(2.4rem, 6.2vw, 4.6rem); line-height: 1.02; font-weight: 750; }
h2 { font-size: clamp(1.8rem, 3.6vw, 2.8rem); line-height: 1.08; font-weight: 720; }
h3 { font-size: 1.12rem; line-height: 1.3; font-weight: 650; letter-spacing: -0.01em; }
p { margin: 0 0 1rem; }
.lead { font-size: clamp(1.1rem, 1.9vw, 1.3rem); color: var(--text-soft); max-width: 40rem; }
.muted { color: var(--muted); }
.small { font-size: 0.9rem; }
.eyebrow { display: inline-flex; align-items: center; gap: 0.55rem; margin: 0 0 1.1rem; font-size: 0.78rem; font-weight: 650;
  letter-spacing: 0.16em; text-transform: uppercase; color: var(--electric); }
.eyebrow::before { content: ""; width: 1.4rem; height: 1px; background: currentColor; opacity: 0.8; }

/* Buttons */
.actions { display: flex; flex-wrap: wrap; gap: 0.8rem; margin-top: 2rem; }
.button { display: inline-flex; align-items: center; gap: 0.5rem; padding: 0.8rem 1.35rem; border-radius: 999px;
  font-weight: 600; font-size: 0.98rem; text-decoration: none; border: 1px solid transparent; }
.button-primary { background: var(--text); color: var(--bg); }
.button-primary:hover { background: #ffffff; }
.button-ghost { border-color: var(--line); color: var(--text); background: var(--surface); }
.button-ghost:hover { border-color: rgba(255, 255, 255, 0.24); }

/* Backdrops: one soft glow and a faint grid, nothing animated. */
.backdrop { position: relative; overflow: hidden; isolation: isolate; }
.backdrop::before { content: ""; position: absolute; inset: -20% -10% auto; height: 120%; z-index: -1;
  background: radial-gradient(60% 55% at 70% 20%, rgba(61, 107, 255, 0.22), transparent 70%),
              radial-gradient(40% 40% at 10% 0%, rgba(32, 72, 200, 0.18), transparent 70%); }
.backdrop::after { content: ""; position: absolute; inset: 0; z-index: -1; opacity: 0.5;
  background-image: linear-gradient(var(--line) 1px, transparent 1px), linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 72px 72px; mask-image: linear-gradient(to bottom, black, transparent 85%);
  -webkit-mask-image: linear-gradient(to bottom, black, transparent 85%); }

/* Small layout helpers (no inline styles, so a strict security policy can apply) */
.hero-lead { margin-top: 1.5rem; }
.panel-spaced { margin-top: 2.25rem; }
.product-title { font-size: clamp(1.6rem, 3vw, 2.2rem); margin: 0.6rem 0 0.75rem; }
.status-line { margin-top: 1.25rem; }
.plans-note { margin-top: 1.5rem; }

/* Sections */
.hero { padding: clamp(4rem, 11vw, 8.5rem) 0 clamp(3.5rem, 8vw, 6rem); }
.section { padding: clamp(3.5rem, 8vw, 6.5rem) 0; border-top: 1px solid var(--line); }
.section-tint { background: var(--bg-2); }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); gap: 2rem 4.5rem; align-items: center; }

.principles { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; margin-top: 3rem; }
.principle { border: 1px solid var(--line); background: var(--surface); border-radius: var(--radius); padding: 1.4rem; }
.principle-title { font-size: 1.12rem; line-height: 1.3; font-weight: 650; letter-spacing: -0.01em; }
.principle p { margin: 0.35rem 0 0; color: var(--muted); font-size: 0.95rem; }
.principle .index { font-size: 0.78rem; letter-spacing: 0.14em; color: var(--electric); font-weight: 650; }

.panel { border: 1px solid var(--line); background: linear-gradient(180deg, var(--surface-strong), var(--surface));
  border-radius: calc(var(--radius) + 6px); padding: clamp(1.5rem, 4vw, 3rem); }

/* iPhone frame around a real screenshot */
.device { position: relative; width: min(100%, 300px); margin: 0 auto; padding: 10px; border-radius: 46px;
  background: linear-gradient(145deg, #2a3142, #11151f); box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08),
  0 40px 80px -30px rgba(61, 107, 255, 0.45), 0 30px 60px -30px rgba(0, 0, 0, 0.8); }
.device img { display: block; width: 100%; height: auto; border-radius: 37px; aspect-ratio: 600 / 1298; background: #f6f1ea; }
.device-glow { position: relative; }
.device-glow::before { content: ""; position: absolute; inset: 8% -6%; z-index: 0; border-radius: 50%;
  background: radial-gradient(closest-side, rgba(61, 107, 255, 0.35), transparent); filter: blur(10px); }
.device-glow .device { z-index: 1; }

.badge { display: inline-block; font-size: 0.8rem; font-weight: 600; padding: 0.3rem 0.75rem; border-radius: 999px;
  border: 1px solid var(--line); color: var(--text-soft); background: var(--surface); margin: 0 0.4rem 0.6rem 0; }

/* Showcase (tabs) */
.showcase { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr); gap: 2.5rem 4rem; align-items: center; margin-top: 2.5rem; }
.tabs { display: grid; gap: 0.6rem; }
.tab { all: unset; box-sizing: border-box; cursor: pointer; display: block; width: 100%; border: 1px solid var(--line);
  border-radius: 16px; padding: 1rem 1.15rem; background: transparent; color: var(--text-soft); }
.tab:hover { background: var(--surface); }
.tab:focus-visible { outline: 3px solid var(--electric); outline-offset: 2px; }
.tab[aria-selected="true"] { background: var(--surface-strong); border-color: rgba(91, 134, 255, 0.55); color: var(--text); }
.tab .tab-title { font-weight: 650; font-size: 1.02rem; display: block; color: var(--text); }
.tab .tab-text { display: block; font-size: 0.93rem; margin-top: 0.2rem; color: var(--muted); }
.tab[aria-selected="true"] .tab-text { color: var(--text-soft); }
.screens { position: relative; }
.screen-panel figure { margin: 0; }
.screen-panel figcaption { text-align: center; margin-top: 1rem; font-size: 0.85rem; color: var(--muted); }
/* With JavaScript, one panel shows at a time and fades in. Without it, every panel is listed. */
.js .screen-panel[hidden] { display: none; }
.js .screen-panel { animation: fade 260ms ease-out; }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@media (prefers-reduced-motion: reduce) { .js .screen-panel { animation: none; } }
.no-js-list .screen-panel + .screen-panel { margin-top: 2.5rem; }

/* Free and Pro */
.plans { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin-top: 2.25rem; }
.plan { border: 1px solid var(--line); border-radius: var(--radius); padding: 1.6rem; background: var(--surface); }
.plan-pro { border-color: rgba(91, 134, 255, 0.6); background: linear-gradient(180deg, rgba(32, 72, 200, 0.18), var(--surface)); }
.plan ul { margin: 0.75rem 0 0; padding-left: 1.15rem; color: var(--text-soft); }
.plan li { margin: 0.35rem 0; }
.plan .note { color: var(--muted); font-size: 0.88rem; margin: 0.25rem 0 0; }

.checks { list-style: none; padding: 0; margin: 1.25rem 0; display: grid; gap: 0.7rem; }
.checks li { padding-left: 1.6rem; position: relative; color: var(--text-soft); }
.checks li::before { content: ""; position: absolute; left: 0; top: 0.55em; width: 0.6rem; height: 0.6rem; border-radius: 50%;
  background: var(--electric); box-shadow: 0 0 0 4px rgba(91, 134, 255, 0.18); }

.contact-email { font-size: clamp(1.4rem, 3.4vw, 2.3rem); font-weight: 700; letter-spacing: -0.02em; color: var(--text); text-decoration: none;
  border-bottom: 2px solid var(--electric); }
.contact-email:hover { color: #ffffff; }

/* Footer */
.site-footer { border-top: 1px solid var(--line); padding: 3rem 0 2.25rem; font-size: 0.93rem; background: var(--bg); }
.footer-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) repeat(2, minmax(0, 1fr)); gap: 1.75rem 3rem; }
.site-footer h2 { font-size: 0.76rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--muted); margin: 0 0 0.7rem; font-weight: 650; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { margin: 0.4rem 0; }
.site-footer a { color: var(--text-soft); text-decoration: none; }
.site-footer a:hover { color: var(--text); text-decoration: underline; }
.site-footer p { color: var(--muted); margin: 0 0 0.5rem; }
.legal-line { margin-top: 2.25rem; padding-top: 1.25rem; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.84rem; }

@media (max-width: 56rem) {
  .split, .showcase, .footer-grid { grid-template-columns: minmax(0, 1fr); }
  /* On phones the selected screen sits above the feature list, and only the selected feature's
     description shows, so a tap visibly changes the screen. */
  .js .showcase .screens { order: -1; }
  .js .tab .tab-text { display: none; }
  .js .tab[aria-selected="true"] .tab-text { display: block; }
  .tab { padding: 0.8rem 1rem; }
  .principles, .plans { grid-template-columns: minmax(0, 1fr); }
  .device { width: min(100%, 270px); }
}
@media (max-width: 30rem) {
  body { font-size: 16px; }
  .container { padding: 0 1.15rem; }
  .site-nav ul { gap: 0.25rem 1.05rem; }
}

/* Reading pages (privacy, support, 404). Wording comes unchanged from the earlier site. */
.page-main { max-width: 48rem; margin: 0 auto; padding: clamp(3rem, 7vw, 5rem) 1.5rem 4rem; }
.page-main h1 { font-size: clamp(2.1rem, 5vw, 3.2rem); margin-bottom: 1rem; }
.page-main h2 { font-size: clamp(1.3rem, 2.4vw, 1.6rem); margin: 2.5rem 0 0.75rem; }
.page-main h3 { margin: 1.6rem 0 0.4rem; }
.page-main p, .page-main li { color: var(--text-soft); }
.page-main ul { padding-left: 1.25rem; margin: 0 0 1rem; }
.page-main li { margin: 0.4rem 0; }
.page-main .muted { color: var(--muted); }
.card { border: 1px solid var(--line); background: var(--surface); border-radius: var(--radius); padding: 1.4rem 1.4rem 0.6rem; margin: 1.75rem 0; }
.card > :first-child { margin-top: 0; }
.notice { background: #3a2f10; color: #ffe2a0; border-radius: 6px; padding: 0.1rem 0.45rem; font-weight: 600; }
@media (max-width: 30rem) { .page-main { padding-left: 1.15rem; padding-right: 1.15rem; } }