/* QRFlow design system — hand-written, no framework, no external fonts. */
:root {
  --ink: #0f172a;
  --ink-2: #334155;
  --ink-3: #64748b;
  --line: #e2e8f0;
  --line-2: #f1f5f9;
  --bg: #ffffff;
  --bg-2: #f8fafc;
  --bg-3: #f1f5f9;
  --accent: #4f46e5;
  --accent-ink: #ffffff;
  --accent-soft: #eef2ff;
  --accent-2: #06b6d4;
  --ok: #059669;
  --ok-soft: #ecfdf5;
  --warn: #b45309;
  --warn-soft: #fffbeb;
  --danger: #dc2626;
  --danger-soft: #fef2f2;
  --radius: 12px;
  --radius-lg: 18px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .06), 0 8px 24px -12px rgba(15, 23, 42, .18);
  --shadow-lg: 0 24px 60px -28px rgba(15, 23, 42, .35);
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { line-height: 1.2; margin: 0 0 .5em; letter-spacing: -.02em; font-weight: 700; }
h1 { font-size: clamp(2rem, 5vw, 3.25rem); letter-spacing: -.035em; }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
code, kbd, pre { font-family: var(--mono); font-size: .875em; }
hr { border: 0; border-top: 1px solid var(--line); margin: 2rem 0; }
img, svg { max-width: 100%; }

.wrap { width: 100%; max-width: 1140px; margin: 0 auto; padding: 0 24px; }
.wrap-narrow { max-width: 720px; }
.muted { color: var(--ink-3); }
.small { font-size: .875rem; }
.tiny { font-size: .78rem; }
.center { text-align: center; }
.mono { font-family: var(--mono); }
.nowrap { white-space: nowrap; }
.stack > * + * { margin-top: 1rem; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.row-between { display: flex; gap: 16px; align-items: center; justify-content: space-between; flex-wrap: wrap; }
.grow { flex: 1 1 auto; min-width: 0; }
.truncate { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* ------------------------------------------------------------------ nav */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; gap: 24px; height: 62px; }
.brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 800; font-size: 1.08rem; color: var(--ink); letter-spacing: -.03em; }
.brand:hover { text-decoration: none; }
.brand-mark { width: 26px; height: 26px; border-radius: 7px; display: block; }
.nav-links { display: flex; gap: 22px; align-items: center; margin-left: auto; }
.nav-links a { color: var(--ink-2); font-size: .92rem; font-weight: 500; }
.nav-links a:hover { color: var(--ink); text-decoration: none; }

/* --------------------------------------------------------------- buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 10px 18px; border-radius: 10px; border: 1px solid transparent;
  font: inherit; font-size: .93rem; font-weight: 600; cursor: pointer;
  background: var(--accent); color: var(--accent-ink);
  transition: transform .06s ease, box-shadow .15s ease, background .15s ease;
  text-decoration: none; white-space: nowrap;
}
.btn:hover { text-decoration: none; box-shadow: 0 6px 18px -6px rgba(79, 70, 229, .55); }
.btn:active { transform: translateY(1px); }
.btn[disabled], .btn.disabled { opacity: .5; pointer-events: none; }
.btn-ghost { background: transparent; color: var(--ink-2); border-color: var(--line); }
.btn-ghost:hover { background: var(--bg-2); color: var(--ink); box-shadow: none; }
.btn-light { background: #fff; color: var(--ink); border-color: var(--line); }
.btn-light:hover { background: var(--bg-2); box-shadow: none; }
.btn-danger { background: var(--danger); }
.btn-danger:hover { box-shadow: 0 6px 18px -6px rgba(220, 38, 38, .5); }
.btn-sm { padding: 6px 12px; font-size: .83rem; border-radius: 8px; }
.btn-lg { padding: 13px 26px; font-size: 1rem; border-radius: 11px; }
.btn-block { width: 100%; }

/* ---------------------------------------------------------------- forms */
label { display: block; font-size: .86rem; font-weight: 600; color: var(--ink-2); margin-bottom: 6px; }
input[type=text], input[type=email], input[type=password], input[type=url], input[type=number], select, textarea {
  width: 100%; padding: 10px 12px; font: inherit; font-size: .95rem; color: var(--ink);
  background: #fff; border: 1px solid var(--line); border-radius: 10px; outline: none;
  transition: border-color .12s ease, box-shadow .12s ease;
}
input:focus, select:focus, textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
input[type=color] { width: 46px; height: 38px; padding: 3px; border: 1px solid var(--line); border-radius: 9px; background: #fff; cursor: pointer; }
input[type=range] { width: 100%; accent-color: var(--accent); }
.field { margin-bottom: 16px; }
.field-hint { font-size: .8rem; color: var(--ink-3); margin-top: 5px; }
fieldset { border: 0; padding: 0; margin: 0; }

/* ---------------------------------------------------------------- cards */
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 22px; }
.card-pad-lg { padding: 30px; }
.card-flush { padding: 0; overflow: hidden; }
.card-title { font-size: 1.02rem; font-weight: 700; margin: 0 0 4px; }
.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); }

.badge { display: inline-flex; align-items: center; gap: 5px; padding: 2px 9px; border-radius: 999px; font-size: .74rem; font-weight: 700; letter-spacing: .02em; text-transform: uppercase; background: var(--bg-3); color: var(--ink-2); }
.badge-accent { background: var(--accent-soft); color: var(--accent); }
.badge-ok { background: var(--ok-soft); color: var(--ok); }
.badge-warn { background: var(--warn-soft); color: var(--warn); }
.badge-danger { background: var(--danger-soft); color: var(--danger); }

.notice { padding: 12px 16px; border-radius: 11px; font-size: .9rem; border: 1px solid; margin-bottom: 18px; }
.notice-error { background: var(--danger-soft); border-color: #fecaca; color: #991b1b; }
.notice-ok { background: var(--ok-soft); border-color: #a7f3d0; color: #065f46; }
.notice-info { background: var(--accent-soft); border-color: #c7d2fe; color: #3730a3; }
.notice-warn { background: var(--warn-soft); border-color: #fde68a; color: #92400e; }

/* --------------------------------------------------------------- tables */
table { width: 100%; border-collapse: collapse; font-size: .9rem; }
th { text-align: left; font-size: .74rem; letter-spacing: .06em; text-transform: uppercase; color: var(--ink-3); font-weight: 700; padding: 12px 16px; border-bottom: 1px solid var(--line); background: var(--bg-2); }
td { padding: 13px 16px; border-bottom: 1px solid var(--line-2); vertical-align: middle; }
tbody tr:last-child td { border-bottom: 0; }
tbody tr:hover { background: var(--bg-2); }
.table-scroll { overflow-x: auto; }

/* ----------------------------------------------------------------- hero */
.hero { position: relative; overflow: hidden; background: linear-gradient(165deg, #0b1020 0%, #131a35 55%, #1a2247 100%); color: #e2e8f0; padding: 78px 0 90px; }
.hero::after { content: ""; position: absolute; inset: 0; background: radial-gradient(700px 340px at 78% 8%, rgba(79, 70, 229, .38), transparent 65%), radial-gradient(520px 300px at 12% 92%, rgba(6, 182, 212, .22), transparent 60%); pointer-events: none; }
.hero .wrap { position: relative; z-index: 1; }
.hero h1 { color: #fff; margin-bottom: .35em; }
.hero p.lede { font-size: 1.16rem; color: #b6c2da; max-width: 33em; }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 52px; align-items: center; }
@media (max-width: 900px) { .hero-grid { grid-template-columns: 1fr; gap: 34px; } }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; font-size: .78rem; font-weight: 700; letter-spacing: .09em; text-transform: uppercase; color: #a5b4fc; margin-bottom: 18px; }
.hero-card { background: rgba(255, 255, 255, .06); border: 1px solid rgba(255, 255, 255, .13); border-radius: 20px; padding: 22px; backdrop-filter: blur(8px); box-shadow: var(--shadow-lg); }
.hero-card label { color: #c7d2fe; }
.hero-card input[type=text] { background: rgba(255, 255, 255, .95); border-color: transparent; }

.section { padding: 78px 0; }
.section-alt { background: var(--bg-2); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 640px; margin: 0 auto 46px; text-align: center; }
.section-head p { color: var(--ink-3); font-size: 1.05rem; margin: 0; }

.feature { padding: 4px; }
.feature-icon { width: 40px; height: 40px; border-radius: 11px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; margin-bottom: 14px; }
.feature h3 { margin-bottom: 6px; }
.feature p { color: var(--ink-3); font-size: .94rem; margin: 0; }

/* --------------------------------------------------------------- pricing */
.price-card { display: flex; flex-direction: column; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; position: relative; }
.price-card.featured { border-color: var(--accent); box-shadow: 0 20px 50px -30px rgba(79, 70, 229, .8); }
.price-card .amount { font-size: 2.6rem; font-weight: 800; letter-spacing: -.04em; }
.price-card ul { list-style: none; padding: 0; margin: 20px 0 26px; font-size: .92rem; }
.price-card li { padding: 7px 0 7px 26px; position: relative; color: var(--ink-2); }
.price-card li::before { content: ""; position: absolute; left: 2px; top: 14px; width: 12px; height: 6px; border-left: 2px solid var(--ok); border-bottom: 2px solid var(--ok); transform: rotate(-45deg); }
.price-card .btn { margin-top: auto; }
.ribbon { position: absolute; top: -12px; right: 22px; }

/* ------------------------------------------------------------- app shell */
.app-shell { display: grid; grid-template-columns: 232px 1fr; min-height: calc(100vh - 62px); }
@media (max-width: 860px) { .app-shell { grid-template-columns: 1fr; } .side { border-right: 0; border-bottom: 1px solid var(--line); } .side-nav { flex-direction: row; overflow-x: auto; } }
.side { background: var(--bg-2); border-right: 1px solid var(--line); padding: 22px 14px; }
.side-nav { display: flex; flex-direction: column; gap: 3px; }
.side-nav a { display: flex; align-items: center; gap: 9px; padding: 9px 12px; border-radius: 9px; color: var(--ink-2); font-size: .92rem; font-weight: 500; white-space: nowrap; }
.side-nav a:hover { background: #fff; color: var(--ink); text-decoration: none; }
.side-nav a.active { background: #fff; color: var(--accent); font-weight: 650; box-shadow: var(--shadow); }
.main { padding: 30px 32px 70px; min-width: 0; }
@media (max-width: 600px) { .main { padding: 22px 18px 50px; } }
.page-head { margin-bottom: 26px; }
.page-head h1 { font-size: 1.65rem; margin-bottom: 4px; }
.page-head p { color: var(--ink-3); margin: 0; font-size: .95rem; }

.stat { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 17px 19px; }
.stat .k { font-size: .74rem; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-3); font-weight: 700; }
.stat .v { font-size: 1.85rem; font-weight: 800; letter-spacing: -.03em; margin-top: 3px; }
.stat .s { font-size: .8rem; color: var(--ink-3); }

.qr-preview { display: grid; place-items: center; background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; }
.qr-preview svg { width: 100%; height: auto; max-width: 240px; display: block; }

.bar-row { display: grid; grid-template-columns: 110px 1fr 48px; align-items: center; gap: 10px; font-size: .87rem; padding: 3px 0; }
.bar-track { background: var(--bg-3); border-radius: 999px; height: 8px; overflow: hidden; }
.bar-fill { background: linear-gradient(90deg, var(--accent), var(--accent-2)); height: 100%; border-radius: 999px; }

pre.code { background: #0f172a; color: #e2e8f0; padding: 16px 18px; border-radius: 12px; overflow-x: auto; font-size: .82rem; line-height: 1.65; margin: 0 0 16px; }
pre.code .c { color: #94a3b8; }
pre.code .s { color: #86efac; }
pre.code .k { color: #93c5fd; }
.copy-field { display: flex; gap: 8px; align-items: center; }
.copy-field input { font-family: var(--mono); font-size: .84rem; }

.footer { border-top: 1px solid var(--line); background: var(--bg-2); padding: 42px 0; font-size: .88rem; color: var(--ink-3); margin-top: auto; }
.footer a { color: var(--ink-2); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 28px; }
@media (max-width: 760px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
.footer h4 { font-size: .78rem; text-transform: uppercase; letter-spacing: .07em; color: var(--ink-3); margin-bottom: 10px; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer li { padding: 3px 0; }

.faq details { border-bottom: 1px solid var(--line); padding: 16px 0; }
.faq summary { cursor: pointer; font-weight: 650; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--ink-3); font-weight: 400; font-size: 1.3rem; line-height: 1; }
.faq details[open] summary::after { content: "−"; }
.faq p { margin: 12px 0 0; color: var(--ink-3); font-size: .94rem; }

.empty { text-align: center; padding: 56px 20px; color: var(--ink-3); }
.empty h3 { color: var(--ink); }

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e6edf7; --ink-2: #b3c0d4; --ink-3: #8494ab;
    --line: #22293a; --line-2: #1a2130;
    --bg: #0c1018; --bg-2: #111725; --bg-3: #182033;
    --accent: #818cf8; --accent-ink: #0b1020; --accent-soft: #1e2440;
    --ok: #34d399; --ok-soft: #0d2a22; --warn: #fbbf24; --warn-soft: #2a2110;
    --danger: #f87171; --danger-soft: #2c1518;
  }
  .nav { background: rgba(12, 16, 24, .85); }
  .card, .price-card, .stat, .hero-card, .qr-preview { background: var(--bg-2); }
  input[type=text], input[type=email], input[type=password], input[type=url], input[type=number], select, textarea { background: var(--bg-3); color: var(--ink); }
  .btn-light { background: var(--bg-3); color: var(--ink); }
  .side-nav a:hover, .side-nav a.active { background: var(--bg-3); }
  .notice-error { color: #fca5a5; border-color: #4c1d1d; }
  .notice-ok { color: #6ee7b7; border-color: #14432f; }
  .notice-info { color: #c7d2fe; border-color: #2e3563; }
  .notice-warn { color: #fcd34d; border-color: #4a3a12; }
}