/* ═══════════════════════════════════════════════════════════
   WallUPI product site
   One consistent light surface · dark only where it belongs
   (the phone screenshots and the privacy card)
   ═══════════════════════════════════════════════════════════ */

:root {
  /* brand: single blue accent, taken from the logo */
  --blue:       #2d6fe0;
  --blue-dark:  #2160cf;
  --blue-soft:  #eaf1fd;
  --logo-black: #1f2125;

  /* one light page surface, used everywhere */
  --l-page:   #eef1f5;
  --l-card:   #ffffff;
  --l-line:   #e2e6ee;
  --l-line-2: #d4dae4;

  /* dark surfaces: only phone frames, the privacy card, the footer */
  --d-base:   #15171a;
  --d-deep:   #101113;
  --d-card:   #1d1f22;
  --d-line:   #2e3136;
  --on-dark:    #E7E8EC;
  --on-dark-2:  #a6abba;

  /* text */
  --ink:      #16181d;
  --ink-soft: #5a6170;
  --ink-mute: #9aa1af;

  /* risk semantic */
  --safe:     #2f9e5b;
  --amber:    #E3A838;
  --orange:   #F08C2E;
  --red:      #E2554F;

  --maxw: 1180px;
  --radius: 16px;
  --radius-lg: 22px;
  --ease: cubic-bezier(.22,.61,.36,1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background: var(--l-page);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  line-height: 1.55;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

/* ── Logo mark (two-tone W) ──────────────────────────── */
.brand-mark .mk-a { stroke: var(--logo-black); }
.brand-mark .mk-b { stroke: var(--blue); }

/* ── Buttons ─────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: .5rem;
  font-weight: 600; font-size: .95rem;
  border-radius: 999px;
  padding: .7rem 1.3rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .15s var(--ease), box-shadow .2s var(--ease), background .2s, color .2s, border-color .2s;
  white-space: nowrap;
}
.btn:hover { transform: translateY(-2px); }
.btn-sm { padding: .55rem 1.05rem; font-size: .88rem; }
.btn-lg { padding: .85rem 1.7rem; font-size: 1rem; }

.btn-primary { background: var(--blue); color: #fff; box-shadow: 0 8px 20px rgba(45,111,224,.25); }
.btn-primary:hover { background: var(--blue-dark); box-shadow: 0 12px 26px rgba(45,111,224,.34); }

.btn-ghost { background: #fff; color: var(--ink); border-color: var(--l-line-2); }
.btn-ghost:hover { border-color: #b9c0cd; }

.btn-light { background: #fff; color: var(--blue-dark); }
.btn-outline-light { background: transparent; color: #fff; border-color: rgba(255,255,255,.5); }
.btn-outline-light:hover { background: rgba(255,255,255,.12); }

/* ── NAV ─────────────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(12px);
  background: rgba(238,241,245,.78);
  border-bottom: 1px solid transparent;
  transition: background .25s, border-color .25s, box-shadow .25s;
}
.nav.scrolled {
  background: rgba(255,255,255,.88);
  border-bottom-color: var(--l-line);
  box-shadow: 0 4px 20px rgba(20,24,40,.05);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto;
  padding: .9rem 1.5rem;
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
}
.brand { display: inline-flex; align-items: center; gap: .55rem; }
.brand-mark { flex: none; }
.brand-word { font-weight: 800; font-size: 1.32rem; letter-spacing: -.02em; color: var(--ink); }
.brand-upi { color: var(--blue); }

.nav-links { display: flex; gap: 2rem; }
.nav-links a { font-weight: 500; font-size: .95rem; color: var(--ink-soft); transition: color .15s; }
.nav-links a:hover { color: var(--ink); }

.nav-actions { display: flex; align-items: center; gap: .75rem; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav-toggle span { width: 22px; height: 2px; background: var(--ink); border-radius: 2px; transition: .25s 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); }

/* ── HERO ────────────────────────────────────────────── */
.hero { max-width: var(--maxw); margin: 0 auto; padding: 1.5rem 1.5rem 0; }
.hero-card {
  position: relative;
  background: #fafbfd;
  border: 1px solid var(--l-line);
  border-radius: 28px;
  padding: clamp(3.5rem, 9vw, 7rem) 1.5rem clamp(4rem, 8vw, 7rem);
  overflow: hidden;
  box-shadow: 0 24px 50px -34px rgba(30,40,80,.18);
}
.hero-dots {
  position: absolute; inset: 0;
  background-image: radial-gradient(circle, #d6dbe5 1.1px, transparent 1.1px);
  background-size: 24px 24px;
  -webkit-mask-image: radial-gradient(ellipse 78% 68% at 50% 42%, #000 28%, transparent 74%);
  mask-image: radial-gradient(ellipse 78% 68% at 50% 42%, #000 28%, transparent 74%);
  opacity: .6; pointer-events: none;
}
.hero-copy { position: relative; z-index: 3; max-width: 720px; margin: 0 auto; text-align: center; }
.hero-title {
  font-size: clamp(2.6rem, 7vw, 5rem);
  line-height: 1.03; letter-spacing: -.035em; font-weight: 800;
  margin: 0 0 1.4rem;
}
.hero-title .muted { color: #b3b9c4; }
.hero-sub { font-size: clamp(1.05rem, 2vw, 1.28rem); color: var(--ink-soft); max-width: 580px; margin: 0 auto 2rem; }
.hero-sub em { font-style: italic; color: var(--ink); }
.hero-cta { display: flex; gap: .8rem; justify-content: center; flex-wrap: wrap; }
.hero-foot { margin-top: 1.5rem; font-size: .85rem; color: var(--ink-mute); }

.upi-chip { font-weight: 800; font-size: .68em; letter-spacing: .02em; color: var(--blue); }

/* phone frame (intentionally dark, it's the app) */
.phone {
  border-radius: 30px; background: #0a0b0d; padding: 8px;
  border: 1px solid #2a2c31;
  box-shadow: 0 30px 60px -26px rgba(10,15,30,.5);
}
.phone img { border-radius: 23px; }

/* ── STATS ───────────────────────────────────────────── */
.stats { max-width: var(--maxw); margin: 0 auto; padding: 4.5rem 1.5rem 1rem; text-align: center; }
.stats-lead { font-size: clamp(1.1rem, 2.4vw, 1.55rem); color: var(--ink-soft); max-width: 640px; margin: 0 auto 2.5rem; }
.stats-lead strong { color: var(--ink); }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; }
.stat { background: var(--l-card); border: 1px solid var(--l-line); border-radius: var(--radius); padding: 1.6rem 1.2rem; }
.stat-num { font-size: 1.7rem; font-weight: 800; letter-spacing: -.02em; color: var(--blue); }
.stat-label { font-size: .88rem; color: var(--ink-soft); margin-top: .35rem; }

/* ── Section helpers ─────────────────────────────────── */
.section-head { max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem; }
.section-head.center { text-align: center; }
.section-eyebrow { font-weight: 700; font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-soft); margin-bottom: .8rem; }
.section-eyebrow.accent { color: var(--blue); }
.section-title { font-size: clamp(1.9rem, 4vw, 3rem); line-height: 1.08; letter-spacing: -.03em; font-weight: 800; color: var(--ink); margin: 0 auto; max-width: 820px; }
.section-title .muted { color: #b3b9c4; }
.section-desc { font-size: 1.08rem; color: var(--ink-soft); max-width: 620px; margin: 1rem auto 0; }
.section-desc.dark-on-light { margin-left: 0; }

/* ── PROBLEM ─────────────────────────────────────────── */
.problem { max-width: var(--maxw); margin: 0 auto; padding: 5.5rem 1.5rem; text-align: center; }
.problem .section-title { margin-bottom: 2.8rem; }
.problem-flow { display: flex; align-items: stretch; justify-content: center; gap: .6rem; flex-wrap: wrap; }
.flow-step {
  background: var(--l-card); border: 1px solid var(--l-line); border-radius: var(--radius);
  padding: 1.3rem 1.1rem; width: 215px; text-align: left;
}
.flow-step p { margin: .6rem 0 0; font-size: .95rem; color: var(--ink); }
.flow-step.danger { border-color: #f0cdcb; background: #fdf3f3; }
.flow-step.danger p { color: #b23b36; font-weight: 600; }
.flow-n {
  display: inline-flex; width: 28px; height: 28px; border-radius: 50%;
  background: var(--blue-soft); color: var(--blue); font-weight: 800; font-size: .85rem;
  align-items: center; justify-content: center;
}
.flow-step.danger .flow-n { background: #fbdbd9; color: var(--red); }
.flow-arrow { display: flex; align-items: center; color: #c2c8d4; font-size: 1.3rem; }
.problem-note { margin-top: 2.6rem; font-size: 1.15rem; font-weight: 600; color: var(--ink); }

/* ── FEATURE SECTIONS (now light, consistent) ────────── */
.checks, .how, .levels, .screens { padding: 5.5rem 0; }
.how, .screens { padding-top: 1rem; }
.levels { padding-top: 1rem; }

/* ── 5 CHECKS ────────────────────────────────────────── */
.checks-grid {
  max-width: var(--maxw); margin: 3rem auto 0; padding: 0 1.5rem;
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem;
}
.check-card {
  background: var(--l-card); border: 1px solid var(--l-line);
  border-radius: var(--radius-lg); padding: 1.8rem 1.6rem;
  transition: transform .2s var(--ease), border-color .2s, box-shadow .2s;
}
.check-card:hover { transform: translateY(-4px); border-color: var(--l-line-2); box-shadow: 0 18px 36px -24px rgba(30,40,80,.22); }
.check-card h3 { margin: 1rem 0 .5rem; font-size: 1.2rem; color: var(--ink); letter-spacing: -.01em; }
.check-card p { margin: 0; color: var(--ink-soft); font-size: .96rem; }
.check-ico {
  width: 50px; height: 50px; border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
}
.check-ico svg { width: 24px; height: 24px; }
.ico-blue  { background: var(--blue-soft);          color: var(--blue); }
.ico-red   { background: rgba(226,85,79,.12);       color: var(--red); }
.ico-amber { background: rgba(227,168,56,.16);      color: #b9852a; }
.ico-glow  { background: var(--blue);               color: #fff; }
.accent-card { background: var(--blue-soft); border-color: #cfe0fa; }
.accent-card h3 { color: var(--blue-dark); }
.accent-card p { color: #3f5675; }

/* ── 3 TIERS ─────────────────────────────────────────── */
.tiers { max-width: 880px; margin: 3rem auto 0; padding: 0 1.5rem; display: flex; flex-direction: column; gap: 1.1rem; }
.tier {
  display: flex; gap: 1.4rem;
  background: var(--l-card); border: 1px solid var(--l-line);
  border-radius: var(--radius-lg); padding: 1.7rem 1.8rem;
}
.tier-rail { flex: none; }
.tier-num {
  display: flex; width: 46px; height: 46px; border-radius: 50%;
  align-items: center; justify-content: center;
  font-weight: 800; font-size: 1.2rem; color: #fff;
  background: var(--blue);
}
.tier-tag { font-size: .76rem; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; color: var(--blue); }
.tier-body h3 { margin: .35rem 0 .5rem; font-size: 1.3rem; color: var(--ink); letter-spacing: -.01em; }
.tier-body p { margin: 0; color: var(--ink-soft); }

/* ── RISK LEVELS ─────────────────────────────────────── */
.levels-grid { max-width: var(--maxw); margin: 3rem auto 0; padding: 0 1.5rem; display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.1rem; }
.level {
  background: var(--l-card); border: 1px solid var(--l-line);
  border-radius: var(--radius-lg); padding: 1.7rem 1.5rem; border-top-width: 4px;
}
.level p { margin: .8rem 0 0; color: var(--ink-soft); font-size: .95rem; }
.level-top { display: flex; align-items: center; gap: .6rem; }
.level-dot { width: 12px; height: 12px; border-radius: 50%; }
.level-name { font-weight: 700; font-size: 1.1rem; color: var(--ink); }
.lv-safe { border-top-color: var(--safe); }
.lv-safe .level-dot { background: var(--safe); }
.lv-soft { border-top-color: var(--amber); }
.lv-soft .level-dot { background: var(--amber); }
.lv-strong { border-top-color: var(--orange); }
.lv-strong .level-dot { background: var(--orange); }
.lv-critical { border-top-color: var(--red); }
.lv-critical .level-dot { background: var(--red); }

/* ── SCREENS WALKTHROUGH ─────────────────────────────── */
.screens-list { max-width: 980px; margin: 3.5rem auto 0; padding: 0 1.5rem; display: flex; flex-direction: column; gap: 4.5rem; }
.screen-row { display: grid; grid-template-columns: 280px 1fr; gap: 3rem; align-items: center; }
.screen-row:nth-child(even) .screen-phone { order: 2; }
.screen-phone { display: flex; justify-content: center; }
.screen-phone .phone { width: 260px; }
.screen-text .screen-step {
  display: inline-block; font-weight: 700; font-size: .76rem; letter-spacing: .08em; text-transform: uppercase;
  color: var(--blue); background: var(--blue-soft); border: 1px solid #d6e4fb;
  padding: .3rem .75rem; border-radius: 999px; margin-bottom: 1rem;
}
.screen-text h3 { margin: 0 0 .7rem; font-size: clamp(1.4rem, 2.6vw, 1.85rem); letter-spacing: -.02em; color: var(--ink); line-height: 1.15; }
.screen-text p { margin: 0; color: var(--ink-soft); font-size: 1.05rem; max-width: 460px; }

/* ── SAFETY ──────────────────────────────────────────── */
.safety { padding: 5.5rem 0; }
.safety-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem;
  display: grid; grid-template-columns: 1.05fr .95fr; gap: 3rem; align-items: center;
}
.safety-list { list-style: none; padding: 0; margin: 1.8rem 0 0; display: flex; flex-direction: column; gap: 1rem; }
.safety-list li { display: flex; gap: .8rem; font-size: 1.02rem; color: var(--ink); }
.safety-list .check { color: #fff; background: var(--safe); width: 24px; height: 24px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-size: .8rem; flex: none; margin-top: 1px; }
.safety-visual { display: flex; justify-content: center; }
.safety-visual .phone { width: 260px; }

/* ── FAQ ─────────────────────────────────────────────── */
.faq { max-width: 820px; margin: 0 auto; padding: 5.5rem 1.5rem; }
.faq-list { margin-top: 2.5rem; display: flex; flex-direction: column; gap: .8rem; }
.faq-item { background: var(--l-card); border: 1px solid var(--l-line); border-radius: var(--radius); padding: 0 1.4rem; }
.faq-item summary {
  list-style: none; cursor: pointer; font-weight: 600; font-size: 1.08rem; color: var(--ink);
  padding: 1.3rem 0; display: flex; justify-content: space-between; align-items: center; gap: 1rem;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; font-size: 1.5rem; color: var(--blue); font-weight: 400; transition: transform .2s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { margin: 0 0 1.3rem; color: var(--ink-soft); }

/* ── SURVEY ──────────────────────────────────────────── */
.survey { max-width: var(--maxw); margin: 0 auto; padding: 1.5rem 1.5rem 0; }
.survey-inner {
  background: var(--blue-soft); border: 1px solid #d6e4fb;
  border-radius: var(--radius-lg); padding: clamp(2.6rem, 5vw, 3.6rem) 1.5rem;
  text-align: center;
}
.survey-inner h2 { font-size: clamp(1.7rem, 3.4vw, 2.5rem); letter-spacing: -.03em; line-height: 1.1; margin: .5rem 0 .7rem; color: var(--ink); }
.survey-inner p { color: var(--ink-soft); font-size: 1.1rem; max-width: 520px; margin: 0 auto 1.9rem; }

/* ── FOOTER ──────────────────────────────────────────── */
.footer { background: var(--d-deep); color: var(--on-dark-2); padding: 4rem 1.5rem 2rem; }
.footer-inner { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: 1.4fr 2fr; gap: 3rem; }
.brand-footer .brand-word { color: #fff; }
.brand-footer .mk-a { stroke: #fff; }
.brand-footer .mk-b { stroke: #5a8ff0; }
.brand-footer .brand-upi { color: #5a8ff0; }
.footer-tag { margin: 1rem 0 0; font-size: .95rem; max-width: 280px; }
.footer-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.fcol h4 { color: #fff; font-size: .9rem; margin: 0 0 1rem; letter-spacing: .03em; }
.fcol a { display: block; padding: .35rem 0; font-size: .92rem; transition: color .15s; }
.fcol a:hover { color: #fff; }
.footer .upi-chip { color: #5a8ff0; }
.footer-bottom {
  max-width: var(--maxw); margin: 3rem auto 0; padding-top: 1.8rem; border-top: 1px solid var(--d-line);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 1rem; font-size: .85rem;
}

/* ── reveal animation ────────────────────────────────── */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }

/* ── responsive ──────────────────────────────────────── */
@media (max-width: 900px) {
  .checks-grid { grid-template-columns: repeat(2, 1fr); }
  .levels-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .safety-inner { grid-template-columns: 1fr; }
  .safety-visual { order: -1; }
  .footer-inner { grid-template-columns: 1fr; gap: 2rem; }
  .screens-list { gap: 3.5rem; }
  .screen-row { grid-template-columns: 1fr; gap: 1.6rem; justify-items: center; text-align: center; }
  .screen-row:nth-child(even) .screen-phone { order: -1; }
  .screen-text p { margin-left: auto; margin-right: auto; }
}
@media (max-width: 760px) {
  .nav-links {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; gap: 0;
    background: #fff; border-bottom: 1px solid var(--l-line);
    padding: .5rem 1.5rem 1rem; box-shadow: 0 16px 30px -16px rgba(20,24,40,.2);
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: .9rem 0; border-bottom: 1px solid var(--l-line); }
  .nav-toggle { display: flex; }
  .nav-survey, .nav-video { display: none; }
  .flow-arrow { transform: rotate(90deg); }
  .flow-step { width: 100%; max-width: 320px; }
}
@media (max-width: 540px) {
  .checks-grid, .levels-grid, .stats-grid { grid-template-columns: 1fr; }
  .tier { flex-direction: column; gap: .9rem; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
}

/* ── reduced motion ──────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .btn:hover, .check-card:hover { transform: none; }
}

/* ── Standalone pages (download / coming soon) ───────── */
.subpage { min-height: 100vh; display: flex; flex-direction: column; }
.subnav {
  width: 100%; max-width: var(--maxw); margin: 0 auto;
  padding: 1.2rem 1.5rem; display: flex; align-items: center; justify-content: space-between; gap: 1rem;
}
.sublink { font-weight: 600; font-size: .92rem; color: var(--ink-soft); transition: color .15s; }
.sublink:hover { color: var(--ink); }
.subpage-main { flex: 1; display: flex; align-items: center; justify-content: center; padding: 2rem 1.5rem 5rem; }
.subpage-card { width: 100%; max-width: 560px; text-align: center; }
.subpage-card .pill {
  display: inline-block; font-weight: 700; font-size: .76rem; letter-spacing: .08em; text-transform: uppercase;
  color: var(--blue); background: var(--blue-soft); border: 1px solid #d6e4fb;
  padding: .35rem .8rem; border-radius: 999px; margin-bottom: 1.4rem;
}
.subpage-card h1 { font-size: clamp(2rem, 5vw, 3rem); letter-spacing: -.03em; line-height: 1.08; margin: 0 0 1rem; }
.subpage-card .lead { color: var(--ink-soft); font-size: 1.12rem; margin: 0 auto 2rem; max-width: 460px; }
.subpage-actions { display: flex; gap: .8rem; justify-content: center; flex-wrap: wrap; }
.apk-meta { margin-top: 1rem; font-size: .88rem; color: var(--ink-mute); }
.download-steps {
  text-align: left; max-width: 440px; margin: 3rem auto 0;
  background: var(--l-card); border: 1px solid var(--l-line); border-radius: var(--radius); padding: 1.6rem 1.8rem;
}
.download-steps h2 { margin: 0 0 1rem; font-size: 1.05rem; letter-spacing: -.01em; }
.download-steps ol { margin: 0; padding-left: 1.2rem; color: var(--ink-soft); font-size: .96rem; display: flex; flex-direction: column; gap: .6rem; }
.download-note { margin: 2rem auto 0; max-width: 460px; font-size: .85rem; color: var(--ink-mute); }