/* ============================================================
   NumberDrop — style.css
   Palette: deep blue #1e40af · cyan #06b6d4 · slate #1f2937 · lime #10b981
   ============================================================ */

:root {
  --blue: #1e40af;
  --cyan: #06b6d4;
  --slate: #1f2937;
  --lime: #10b981;

  --bg: #f8fafc;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --text-dim: #64748b;

  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 1px 2px rgba(15, 23, 42, 0.06), 0 8px 24px rgba(15, 23, 42, 0.06);
  --gap: 8px;
  --sans: "Outfit", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
}

[data-theme="dark"] {
  --bg: #0b1220;
  --surface: #131c2e;
  --border: #24304a;
  --text: #e8eefc;
  --text-dim: #94a3b8;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.35);
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background 0.3s, color 0.3s;
}

/* subtle wave texture behind the page */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.5;
  background-image: radial-gradient(
      circle at 15% 0%,
      rgba(6, 182, 212, 0.09),
      transparent 45%
    ),
    radial-gradient(circle at 85% 8%, rgba(30, 64, 175, 0.09), transparent 45%);
}

:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; }

a { color: inherit; }

/* ---------- layout ---------- */
.wrap { width: min(1120px, 100% - 40px); margin-inline: auto; }
.section { padding: 72px 0; }
.section-sm { padding: 44px 0; }

/* ---------- header / nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav {
  display: flex;
  align-items: center;
  gap: 26px;
  padding: 14px 0;
  flex-wrap: wrap;
}
.brand {
  display: flex;
  align-items: center;
  gap: 9px;
  font-weight: 700;
  font-size: 19px;
  letter-spacing: -0.02em;
  text-decoration: none;
  margin-right: auto;
}
.brand svg { width: 24px; height: 24px; flex: none; }
.nav-links { display: flex; gap: 20px; flex-wrap: wrap; }
.nav-links a {
  text-decoration: none;
  font-size: 14.5px;
  font-weight: 500;
  color: var(--text-dim);
  padding-bottom: 2px;
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}
.nav-links a:hover { color: var(--text); }
.nav-links a[aria-current="page"] { color: var(--text); border-color: var(--cyan); }

.theme-toggle {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  cursor: pointer;
  display: grid;
  place-items: center;
  font-size: 16px;
  transition: transform 0.3s, border-color 0.2s;
}
.theme-toggle:hover { transform: rotate(-15deg); border-color: var(--cyan); }

/* ---------- typography ---------- */
h1 {
  font-size: clamp(34px, 6vw, 60px);
  line-height: 1.04;
  letter-spacing: -0.035em;
  font-weight: 700;
}
h2 {
  font-size: clamp(24px, 3.4vw, 34px);
  line-height: 1.15;
  letter-spacing: -0.025em;
  font-weight: 700;
}
h3 { font-size: 19px; font-weight: 600; letter-spacing: -0.015em; }
.lede { font-size: 18px; color: var(--text-dim); max-width: 56ch; }
.eyebrow {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}
.tagline { font-weight: 600; color: var(--cyan); }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 12px 24px;
  font: inherit;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.18s, background 0.2s, box-shadow 0.2s;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: linear-gradient(135deg, var(--blue), var(--cyan));
  color: #fff;
  box-shadow: 0 6px 18px rgba(6, 182, 212, 0.28);
}
.btn-primary:hover { box-shadow: 0 10px 26px rgba(6, 182, 212, 0.38); }
.btn-ghost {
  background: var(--surface);
  border-color: var(--border);
  color: var(--text);
}
.btn-ghost:hover { border-color: var(--cyan); }
.btn-sm { padding: 8px 16px; font-size: 13.5px; }
.btn-danger { background: none; border-color: var(--border); color: #dc2626; }
.btn-danger:hover { border-color: #dc2626; }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }

/* ---------- cards ---------- */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow);
}
.grid { display: grid; gap: 18px; }
.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)); }

/* ---------- forms ---------- */
.field { margin-bottom: 18px; }
.field label {
  display: block;
  font-size: 13.5px;
  font-weight: 600;
  margin-bottom: 6px;
}
.field .hint { font-size: 12.5px; color: var(--text-dim); font-weight: 400; }
input[type="text"],
input[type="number"],
select,
textarea {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 11px 13px;
  font: inherit;
  font-size: 15px;
  color: var(--text);
  transition: border-color 0.2s, box-shadow 0.2s;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--cyan);
  box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.16);
}
textarea { font-family: var(--mono); font-size: 13.5px; resize: vertical; min-height: 150px; }
.check { display: flex; align-items: center; gap: 9px; font-size: 14.5px; cursor: pointer; }
.check input { width: 17px; height: 17px; accent-color: var(--cyan); cursor: pointer; }
.row { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); }
.hidden { display: none !important; }

/* ---------- stats ---------- */
.stats { display: grid; gap: 1px; background: var(--border); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); }
.stat { background: var(--surface); padding: 16px 18px; }
.stat dt { font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-dim); }
.stat dd { font-size: 22px; font-weight: 700; letter-spacing: -0.02em; margin-top: 5px; }

/* ---------- results output ---------- */
.output {
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.8;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
  max-height: 340px;
  overflow: auto;
  white-space: pre-wrap;
  word-break: break-word;
}

/* ---------- table ---------- */
table { width: 100%; border-collapse: collapse; font-size: 14.5px; }
th, td { text-align: left; padding: 13px 12px; border-bottom: 1px solid var(--border); }
th { font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-dim); font-weight: 500; }
tbody tr { transition: background 0.15s; }
tbody tr:hover { background: color-mix(in srgb, var(--cyan) 7%, transparent); }
.table-scroll { overflow-x: auto; }

/* ---------- badges ---------- */
.badge {
  display: inline-block;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 4px 9px;
  border-radius: 999px;
  border: 1px solid var(--border);
}
.badge-pending { color: var(--text-dim); }
.badge-processing { color: var(--cyan); border-color: var(--cyan); }
.badge-completed { color: var(--lime); border-color: var(--lime); }
.badge-failed { color: #dc2626; border-color: #dc2626; }

/* ---------- alerts ---------- */
.alert {
  border-radius: var(--radius-sm);
  padding: 12px 15px;
  font-size: 14.5px;
  margin-bottom: 16px;
  border: 1px solid;
}
.alert-error { background: rgba(220, 38, 38, 0.08); border-color: rgba(220, 38, 38, 0.4); color: #b91c1c; }
.alert-ok { background: rgba(16, 185, 129, 0.08); border-color: rgba(16, 185, 129, 0.4); color: #047857; }
.alert-warn { background: rgba(245, 158, 11, 0.08); border-color: rgba(245, 158, 11, 0.4); color: #b45309; }
[data-theme="dark"] .alert-error { color: #fca5a5; }
[data-theme="dark"] .alert-ok { color: #6ee7b7; }
[data-theme="dark"] .alert-warn { color: #fcd34d; }

/* ---------- spinner ---------- */
.spinner {
  width: 17px; height: 17px;
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* droplet ripple on generate */
@keyframes ripple {
  0% { transform: scale(0.6); opacity: 0.55; }
  100% { transform: scale(2.4); opacity: 0; }
}
.ripple {
  position: absolute;
  border-radius: 50%;
  background: var(--cyan);
  pointer-events: none;
  animation: ripple 0.6s ease-out forwards;
}

/* ---------- empty state ---------- */
.empty { text-align: center; padding: 48px 20px; color: var(--text-dim); }
.empty svg { width: 42px; height: 42px; opacity: 0.4; margin-bottom: 12px; }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 30px 0;
  margin-top: 40px;
  font-size: 14px;
  color: var(--text-dim);
}
.site-footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.site-footer a { text-decoration: none; }
.site-footer a:hover { color: var(--cyan); }

/* ---------- distribution SVG cards ---------- */
.dist-shape { width: 100%; height: 90px; display: block; margin: 16px 0; }

/* ---------- reveal ---------- */
.reveal { opacity: 0; transform: translateY(16px); }
.reveal.in {
  opacity: 1;
  transform: none;
  transition: opacity 0.6s cubic-bezier(0.2, 0.8, 0.2, 1),
    transform 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  .reveal { opacity: 1; transform: none; }
}

@media (max-width: 640px) {
  .section { padding: 48px 0; }
  .nav { gap: 14px; }
  .nav-links { order: 3; width: 100%; gap: 16px; }
}