:root {
  /* Roundcube Elastic-inspired palette (light, modern) */
  --bg: #f4f4f4;            /* app background (Roundcube login/header bg) */
  --bg-2: #fbfbfb;          /* footer / searchbar */
  --surface: #ffffff;       /* cards, content */
  --surface-2: #f1f3f4;     /* hover / input-group bg */
  --sidebar: #2f3a3f;       /* Roundcube dark sidebar */
  --sidebar-2: #45555c;     /* sidebar hover/selected */
  --text: #2c363a;          /* Roundcube body text */
  --text-dim: #5b6366;
  --text-mute: #737677;     /* Roundcube labels/hints */
  --border: #d4dbde;        /* Roundcue primary border */
  --border-strong: #ced4da;
  --accent: #37beff;        /* Roundcube button-primary / selection */
  --accent-2: #00acff;      /* Roundcube link */
  --accent-3: #008cd0;      /* deep blue, gradient end */
  --accent-soft: #d0f0ff;   /* Roundcube slider range / soft tint */
  --success: #41b849;       /* Roundcube success/selected */
  --danger: #ff5552;        /* Roundcube danger/flagged */
  --radius: 12px;
  --radius-lg: 18px;
  --shadow: 0 20px 60px -28px rgba(47, 58, 63, 0.35);
  --shadow-sm: 0 4px 16px -8px rgba(47, 58, 63, 0.18);
  --font: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Space Grotesk', var(--font);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
  position: relative;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Background ---------- */
.bg-orbs { position: fixed; inset: 0; z-index: -2; overflow: hidden; }
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.28;
  animation: float 22s ease-in-out infinite;
}
.orb-1 { width: 520px; height: 520px; background: #37beff; top: -180px; left: -120px; }
.orb-2 { width: 460px; height: 460px; background: #00acff; top: 30%; right: -180px; animation-delay: -7s; }
.orb-3 { width: 420px; height: 420px; background: #84d7ff; bottom: -180px; left: 35%; animation-delay: -14s; }

body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(1200px 600px at 50% -10%, rgba(55,190,255,0.10), transparent 60%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
}

.noise { display: none; }

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, -30px) scale(1.08); }
  66% { transform: translate(-30px, 25px) scale(0.95); }
}

/* ---------- Nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  padding: 16px 0;
  backdrop-filter: blur(14px);
  background: rgba(244, 244, 244, 0.78);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1240px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
  padding: 0 clamp(20px, 6vw, 80px);
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); font-family: var(--font-display); font-weight: 700; font-size: 1.15rem; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 10px; color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-3)); box-shadow: 0 8px 20px -8px rgba(55,190,255,0.6); }
.brand-mark svg { width: 20px; height: 20px; }
.brand-mark.small { width: 28px; height: 28px; }
.brand-mark.small svg { width: 16px; height: 16px; }
.brand-name .dot { color: var(--text-mute); }
.nav-links { display: flex; gap: 28px; }
.nav-links a { color: var(--text-dim); text-decoration: none; font-size: 0.95rem; font-weight: 500; transition: color 0.2s; }
.nav-links a:hover { color: var(--accent-2); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 22px; border-radius: 999px;
  font-family: var(--font); font-weight: 600; font-size: 0.97rem;
  text-decoration: none; border: 1px solid transparent; cursor: pointer;
  transition: transform 0.2s, box-shadow 0.25s, background 0.2s, border-color 0.2s, color 0.2s;
  white-space: nowrap;
}
.btn svg { width: 18px; height: 18px; }
.btn-sm { padding: 9px 16px; font-size: 0.88rem; }
.btn-lg { padding: 16px 32px; font-size: 1.05rem; }
.btn-primary {
  color: #fff;
  background: var(--accent);
  box-shadow: 0 12px 30px -12px rgba(55,190,255,0.7);
}
.btn-primary:hover { background: #1eb6ff; transform: translateY(-2px); box-shadow: 0 18px 40px -12px rgba(55,190,255,0.85); }
.btn-ghost {
  color: var(--text); background: var(--surface); border-color: var(--border);
  box-shadow: var(--shadow-sm);
}
.btn-ghost:hover { background: var(--surface-2); border-color: var(--border-strong); transform: translateY(-2px); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 60px;
  align-items: center;
  max-width: 1240px;
  margin: 0 auto;
  padding: clamp(60px, 9vw, 120px) clamp(20px, 6vw, 80px) 80px;
}
.hero-inner { max-width: 560px; }
.pill {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 14px; border-radius: 999px;
  font-size: 0.82rem; font-weight: 500; color: var(--text-dim);
  background: var(--surface); border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  margin-bottom: 26px;
}
.pulse { width: 8px; height: 8px; border-radius: 50%; background: var(--success); box-shadow: 0 0 0 0 rgba(65,184,73,0.7); animation: pulse 2s infinite; }
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(65,184,73,0.6); }
  70% { box-shadow: 0 0 0 10px rgba(65,184,73,0); }
  100% { box-shadow: 0 0 0 0 rgba(65,184,73,0); }
}
.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 6vw, 4.6rem);
  font-weight: 700; line-height: 1.02; letter-spacing: -0.02em;
  margin-bottom: 24px;
  color: var(--text);
}
.gradient-text {
  background: linear-gradient(120deg, var(--accent) 0%, var(--accent-2) 50%, var(--accent-3) 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
  background-size: 200% auto;
  animation: shimmer 6s linear infinite;
}
@keyframes shimmer { to { background-position: 200% center; } }
.hero-sub { font-size: 1.18rem; color: var(--text-dim); max-width: 480px; margin-bottom: 36px; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 56px; }
.hero-stats { display: flex; gap: 36px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat strong { font-family: var(--font-display); font-size: 1.7rem; font-weight: 600; color: var(--text); }
.stat span { font-size: 0.85rem; color: var(--text-mute); }

/* Hero card / mockup - Roundcube-style sidebar + message list */
.hero-card { perspective: 1600px; }
.card-window {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  transform: rotateY(-13deg) rotateX(6deg) translateZ(0);
  transform-origin: left center;
  transition: transform 0.5s ease;
}
.hero-card:hover .card-window { transform: rotateY(-6deg) rotateX(3deg); }
.card-bar {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-2);
}
.card-bar i { width: 11px; height: 11px; border-radius: 50%; background: #ff5f57; }
.card-bar i:nth-child(2) { background: #febc2e; }
.card-bar i:nth-child(3) { background: #28c840; }
.card-bar span { margin-left: 10px; font-size: 0.8rem; color: var(--text-mute); font-family: var(--font-display); }

/* two-pane layout: dark sidebar + message list */
.card-body { display: grid; grid-template-columns: 132px 1fr; min-height: 360px; }
.card-side {
  background: var(--sidebar);
  color: #cdd6d9;
  padding: 14px 10px;
  display: flex; flex-direction: column; gap: 2px;
  border-right: 1px solid rgba(0,0,0,0.15);
}
.side-item {
  display: flex; align-items: center; gap: 9px;
  padding: 9px 10px; border-radius: 8px;
  font-size: 0.82rem; color: #cdd6d9;
  transition: background 0.2s, color 0.2s;
}
.side-item .ic { width: 15px; height: 15px; opacity: 0.85; flex: none; }
.side-item.active { background: var(--sidebar-2); color: #fff; }
.side-item:hover { background: rgba(255,255,255,0.06); }
.side-sep { height: 1px; background: rgba(255,255,255,0.08); margin: 8px 6px; }
.side-badge { margin-left: auto; font-size: 0.72rem; font-weight: 600; color: #fff; background: var(--accent); border-radius: 999px; padding: 1px 7px; }

.card-list { padding: 10px; background: var(--surface); }
.mail-row {
  display: grid;
  grid-template-columns: 36px 1fr auto;
  gap: 12px; align-items: center;
  padding: 12px 12px; border-radius: 10px;
  margin-bottom: 4px; transition: background 0.2s;
}
.mail-row:hover { background: var(--surface-2); }
.mail-row.unread { background: var(--accent-soft); }
.mail-row.unread .mail-from { color: var(--text); font-weight: 600; }
.mail-row.unread .mail-sub { font-weight: 600; }
.avatar { width: 36px; height: 36px; border-radius: 10px; display: grid; place-items: center; font-weight: 700; color: #fff; font-family: var(--font-display); font-size: 0.85rem; }
.a1 { background: linear-gradient(135deg, #ff7a59, #ff3d77); }
.a2 { background: linear-gradient(135deg, var(--accent), var(--accent-3)); }
.a3 { background: linear-gradient(135deg, #84d7ff, var(--accent-2)); }
.a4 { background: linear-gradient(135deg, #ffd166, #ef476f); }
.mail-from { font-size: 0.88rem; font-weight: 500; color: var(--text-dim); }
.mail-sub { font-size: 0.85rem; color: var(--text); margin-top: 2px; }
.mail-prev { font-size: 0.78rem; color: var(--text-mute); margin-top: 2px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 260px; }
.mail-time { font-size: 0.75rem; color: var(--text-mute); align-self: flex-start; margin-top: 4px; }

/* ---------- Sections ---------- */
section { max-width: 1240px; margin: 0 auto; padding: clamp(60px, 8vw, 100px) clamp(20px, 6vw, 80px); }
.section-head { text-align: center; margin-bottom: 56px; }
.kicker { display: inline-block; font-family: var(--font-display); font-size: 0.82rem; font-weight: 600; letter-spacing: 0.16em; text-transform: uppercase; color: var(--accent-2); margin-bottom: 14px; }
.section-head h2 { font-family: var(--font-display); font-size: clamp(1.9rem, 4vw, 2.8rem); font-weight: 600; letter-spacing: -0.02em; line-height: 1.15; max-width: 680px; margin: 0 auto; color: var(--text); }

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature {
  padding: 30px; border-radius: var(--radius);
  background: var(--surface); border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.feature:hover { transform: translateY(-6px); border-color: var(--border-strong); box-shadow: var(--shadow); }
.feature-icon {
  width: 52px; height: 52px; border-radius: 14px; display: grid; place-items: center;
  color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-3));
  margin-bottom: 20px; box-shadow: 0 12px 24px -12px rgba(55,190,255,0.6);
}
.feature-icon svg { width: 26px; height: 26px; }
.feature h3 { font-family: var(--font-display); font-size: 1.25rem; font-weight: 600; margin-bottom: 8px; color: var(--text); }
.feature p { color: var(--text-dim); font-size: 0.96rem; }

/* Security */
.security-card {
  display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 50px;
  padding: clamp(32px, 5vw, 56px);
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
}
.security-left h2 { font-family: var(--font-display); font-size: clamp(1.6rem, 3vw, 2.2rem); font-weight: 600; line-height: 1.2; margin-bottom: 18px; color: var(--text); }
.security-left p { color: var(--text-dim); margin-bottom: 28px; }
.security-list { list-style: none; display: flex; flex-direction: column; gap: 16px; align-self: center; }
.security-list li { display: flex; align-items: center; gap: 12px; font-size: 1rem; color: var(--text); }
.check {
  display: grid; place-items: center; width: 26px; height: 26px; border-radius: 50%;
  background: rgba(65,184,73,0.15); color: var(--success); font-weight: 700; font-size: 0.85rem;
}

/* CTA */
.cta { text-align: center; }
.cta-inner {
  padding: clamp(48px, 7vw, 90px) clamp(24px, 5vw, 60px);
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--accent-soft), #eaf6ff);
  border: 1px solid var(--border);
  position: relative; overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.cta-inner h2 { font-family: var(--font-display); font-size: clamp(1.9rem, 4vw, 2.8rem); font-weight: 600; margin-bottom: 14px; color: var(--text); }
.cta-inner p { color: var(--text-dim); font-size: 1.12rem; margin-bottom: 32px; }

/* Footer */
.footer { border-top: 1px solid var(--border); margin-top: 40px; background: var(--bg-2); }
.footer-inner {
  max-width: 1240px; margin: 0 auto;
  padding: 36px clamp(20px, 6vw, 80px);
  display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap;
}
.footer-brand { display: flex; align-items: center; gap: 12px; color: var(--text-dim); font-size: 0.95rem; }
.footer-links { display: flex; gap: 22px; }
.footer-links a { color: var(--text-dim); text-decoration: none; font-size: 0.92rem; transition: color 0.2s; }
.footer-links a:hover { color: var(--accent-2); }
.footer-copy { color: var(--text-mute); font-size: 0.85rem; }

/* ---------- Dark mode (Roundcube Elastic dark palette) ---------- */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #21292c;            /* @color-dark-background */
    --bg-2: #161b1d;          /* @color-dark-popover-background (footer) */
    --surface: #2c373a;       /* @color-dark-list-border (elevated card) */
    --surface-2: #374549;     /* @color-dark-list-selected-background (hover) */
    --sidebar: #161b1d;       /* darkest recess (popover bg) */
    --sidebar-2: #2c373a;     /* sidebar hover/selected */
    --text: #c5d1d3;          /* @color-dark-font */
    --text-dim: #9aa7a9;      /* @color-dark-hint */
    --text-mute: #748083;
    --border: #374549;        /* subtle on surfaces */
    --border-strong: #4d6066; /* @color-dark-border */
    --accent-soft: #1f3942;   /* dark blue tint (unread / CTA) */
    --shadow: 0 20px 60px -28px rgba(0, 0, 0, 0.6);
    --shadow-sm: 0 4px 16px -8px rgba(0, 0, 0, 0.5);
  }
  /* primary button = darken(#37beff, 30%) = @color-dark-main */
  .btn-primary { background: #1d6080; box-shadow: 0 12px 30px -14px rgba(29, 96, 128, 0.7); }
  .btn-primary:hover { background: #286a90; }
  .nav { background: rgba(33, 41, 44, 0.78); }
  .footer { background: var(--bg-2); }
  .cta-inner {
    background: linear-gradient(135deg, var(--accent-soft), #18252b);
    border-color: var(--border-strong);
  }
  .orb { opacity: 0.18; }
}

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.7s cubic-bezier(.2,.8,.2,1), transform 0.7s cubic-bezier(.2,.8,.2,1); }
.reveal.in { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .hero { grid-template-columns: 1fr; gap: 50px; }
  .hero-card { order: -1; max-width: 520px; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .security-card { grid-template-columns: 1fr; gap: 36px; }
}
@media (max-width: 640px) {
  .nav-links { display: none; }
  .feature-grid { grid-template-columns: 1fr; }
  .hero-stats { gap: 24px; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
  .card-window { transform: none; }
  .hero-card:hover .card-window { transform: none; }
  .card-body { grid-template-columns: 56px 1fr; }
  .side-item span.lbl { display: none; }
  .side-item { justify-content: center; }
  .side-badge { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
  .reveal { opacity: 1; transform: none; }
}