/* ════════════════════════════════════════════════════════════════
   FINTA 2040 — LIQUID GLASS DESIGN SYSTEM
   Blue spectrum · light/dark · glassmorphism · responsive
   Theme is driven by [data-theme="light"|"dark"] on <html>,
   defaulting to the OS preference via prefers-color-scheme.
   ════════════════════════════════════════════════════════════════ */

/* ─── Fonts ─────────────────────────────────────────────────── */
/* Loaded from Google Fonts in each page <head>:
   Space Grotesk (display) · Inter (text) · JetBrains Mono (code) */

/* ─── Core tokens (dark = default) ──────────────────────────── */
:root {
  color-scheme: dark;

  /* Depth layers */
  --bg0: #030712;             /* void                      */
  --bg1: #060d1f;             /* page background           */
  --bg2: #0a142e;             /* raised surface            */
  --bg3: #101c3d;             /* highest surface           */

  /* Liquid glass */
  --glass:        rgba(96, 145, 255, 0.055);
  --glass-strong: rgba(96, 145, 255, 0.10);
  --glass-brd:    rgba(148, 184, 255, 0.16);
  --glass-brd-hi: rgba(190, 214, 255, 0.38);
  --glass-blur:   22px;
  --glass-inset:  inset 0 1px 0 rgba(255,255,255,0.09),
                  inset 0 -1px 0 rgba(0,0,0,0.18);

  /* Blue spectrum */
  --blue:      #3b82f6;
  --blue-hi:   #60a5fa;
  --blue-lo:   #1d4ed8;
  --cyan:      #22d3ee;
  --ice:       #a5c8ff;
  --violet:    #818cf8;

  /* Text */
  --txt:      #e6eeff;
  --txt-2:    #9fb3d9;
  --txt-3:    #5c6f96;

  /* Status */
  --ok:    #34d399;
  --warn:  #fbbf24;
  --err:   #fb7185;

  /* Glow */
  --glow:    0 0 24px rgba(59,130,246,.35), 0 0 64px rgba(34,211,238,.12);
  --glow-sm: 0 0 12px rgba(59,130,246,.30);

  /* Shape */
  --r-sm: 10px;
  --r:    18px;
  --r-lg: 28px;

  /* Motion */
  --ease: cubic-bezier(.22,.9,.28,1);

  /* Type */
  --f-display: 'Space Grotesk', 'Inter', system-ui, sans-serif;
  --f-text:    'Inter', system-ui, -apple-system, sans-serif;
  --f-mono:    'JetBrains Mono', 'SF Mono', 'Cascadia Code', monospace;

  /* Aurora orbs */
  --orb-a: rgba(37, 99, 235, 0.34);
  --orb-b: rgba(34, 211, 238, 0.20);
  --orb-c: rgba(129, 140, 248, 0.22);

  --nav-bg: rgba(6, 13, 31, 0.62);
  --code-bg: rgba(3, 7, 18, 0.72);
  --shadow-lift: 0 18px 50px -18px rgba(2, 8, 30, 0.85);
}

/* Light theme */
:root[data-theme="light"] {
  color-scheme: light;

  --bg0: #eef4ff;
  --bg1: #f4f8ff;
  --bg2: #ffffff;
  --bg3: #ffffff;

  --glass:        rgba(255, 255, 255, 0.52);
  --glass-strong: rgba(255, 255, 255, 0.74);
  --glass-brd:    rgba(59, 110, 220, 0.16);
  --glass-brd-hi: rgba(59, 110, 220, 0.36);
  --glass-inset:  inset 0 1px 0 rgba(255,255,255,0.9),
                  inset 0 -1px 0 rgba(30,64,175,0.05);

  --blue:    #2563eb;
  --blue-hi: #3b82f6;
  --blue-lo: #1e40af;
  --cyan:    #0891b2;
  --ice:     #1e40af;
  --violet:  #6366f1;

  --txt:    #0b1a3a;
  --txt-2:  #3b4f79;
  --txt-3:  #7488b3;

  --ok:   #059669;
  --warn: #b45309;
  --err:  #e11d48;

  --glow:    0 0 24px rgba(37,99,235,.18), 0 0 64px rgba(8,145,178,.08);
  --glow-sm: 0 0 12px rgba(37,99,235,.16);

  --orb-a: rgba(96, 165, 250, 0.38);
  --orb-b: rgba(103, 232, 249, 0.30);
  --orb-c: rgba(165, 180, 252, 0.34);

  --nav-bg: rgba(244, 248, 255, 0.66);
  --code-bg: rgba(11, 26, 58, 0.94);
  --shadow-lift: 0 18px 44px -20px rgba(30, 64, 175, 0.28);
}

/* System preference fallback when no explicit choice stored */
@media (prefers-color-scheme: light) {
  :root:not([data-theme]) { color-scheme: light; }
}

/* ─── Reset & base ──────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; overflow-x: clip; }

body {
  background: var(--bg1);
  color: var(--txt);
  font-family: var(--f-text);
  font-size: 16px;
  line-height: 1.65;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
  transition: background .45s var(--ease), color .45s var(--ease);
}

::selection { background: rgba(59,130,246,.35); }

::-webkit-scrollbar { width: 9px; height: 9px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--glass-brd-hi); border-radius: 8px; }
::-webkit-scrollbar-thumb:hover { background: var(--blue); }

img { max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
button:focus { outline: none; }
button:focus-visible { outline: 2px solid var(--blue-hi); outline-offset: 2px; }

/* ─── Aurora background ─────────────────────────────────────── */
.aurora {
  position: fixed;
  inset: 0;
  z-index: -2;
  overflow: hidden;
  pointer-events: none;
  background:
    radial-gradient(60% 45% at 12% -8%,  var(--orb-a) 0%, transparent 62%),
    radial-gradient(48% 38% at 88% 6%,   var(--orb-c) 0%, transparent 60%),
    radial-gradient(70% 55% at 50% 115%, var(--orb-b) 0%, transparent 62%);
}
.aurora::before, .aurora::after {
  content: '';
  position: absolute;
  width: 56vmax; height: 56vmax;
  border-radius: 50%;
  filter: blur(90px);
  opacity: .55;
  will-change: transform;
}
.aurora::before {
  background: radial-gradient(circle at 30% 30%, var(--orb-a), transparent 65%);
  top: -18vmax; left: -12vmax;
  animation: drift-a 26s ease-in-out infinite alternate;
}
.aurora::after {
  background: radial-gradient(circle at 60% 60%, var(--orb-b), transparent 65%);
  bottom: -22vmax; right: -14vmax;
  animation: drift-b 32s ease-in-out infinite alternate;
}
@keyframes drift-a {
  from { transform: translate(0,0) scale(1); }
  to   { transform: translate(9vmax, 6vmax) scale(1.15); }
}
@keyframes drift-b {
  from { transform: translate(0,0) scale(1.1); }
  to   { transform: translate(-8vmax, -7vmax) scale(0.95); }
}

/* Fine grid overlay for depth */
.gridlines {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(to right,  rgba(120,160,255,.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(120,160,255,.045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(75% 60% at 50% 32%, black 0%, transparent 100%);
  -webkit-mask-image: radial-gradient(75% 60% at 50% 32%, black 0%, transparent 100%);
}
:root[data-theme="light"] .gridlines {
  background-image:
    linear-gradient(to right,  rgba(37,99,235,.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(37,99,235,.06) 1px, transparent 1px);
}

@media (prefers-reduced-motion: reduce) {
  .aurora::before, .aurora::after { animation: none; }
  * { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

/* ─── Liquid glass primitives ───────────────────────────────── */
.glass {
  position: relative;
  background: var(--glass);
  border: 1px solid var(--glass-brd);
  border-radius: var(--r);
  backdrop-filter: blur(var(--glass-blur)) saturate(1.5);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(1.5);
  box-shadow: var(--glass-inset), var(--shadow-lift);
  transition: border-color .35s var(--ease), transform .35s var(--ease),
              box-shadow .35s var(--ease), background .35s var(--ease);
}
.glass::before {
  /* specular sweep along the top edge */
  content: '';
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  border-radius: inherit;
  background: linear-gradient(90deg,
    transparent 4%, var(--glass-brd-hi) 28%, transparent 68%);
  pointer-events: none;
}
.glass--hover:hover {
  border-color: var(--glass-brd-hi);
  background: var(--glass-strong);
  transform: translateY(-3px);
  box-shadow: var(--glass-inset), var(--shadow-lift), var(--glow-sm);
}
.glass--strong { background: var(--glass-strong); }

/* ─── Buttons ───────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .55rem;
  padding: .82rem 1.7rem;
  border-radius: 999px;
  font-family: var(--f-display);
  font-weight: 600;
  font-size: .95rem;
  letter-spacing: .01em;
  border: 1px solid transparent;
  transition: all .3s var(--ease);
  white-space: nowrap;
}
.btn--primary {
  color: #fff;
  background: linear-gradient(135deg, var(--blue-hi), var(--blue-lo));
  box-shadow: 0 8px 26px -8px rgba(37,99,235,.65),
              inset 0 1px 0 rgba(255,255,255,.28);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 34px -8px rgba(37,99,235,.8),
              inset 0 1px 0 rgba(255,255,255,.28), var(--glow-sm);
}
.btn--ghost {
  color: var(--txt);
  background: var(--glass);
  border-color: var(--glass-brd);
  backdrop-filter: blur(14px) saturate(1.4);
  -webkit-backdrop-filter: blur(14px) saturate(1.4);
}
.btn--ghost:hover {
  border-color: var(--glass-brd-hi);
  background: var(--glass-strong);
  transform: translateY(-2px);
}
.btn--sm { padding: .5rem 1.05rem; font-size: .84rem; }

/* ─── Chips / badges ────────────────────────────────────────── */
.chip {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .34rem .9rem;
  border-radius: 999px;
  font-family: var(--f-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--ice);
  background: var(--glass);
  border: 1px solid var(--glass-brd);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.chip .dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan);
  animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse { 0%,100% { opacity: 1 } 50% { opacity: .35 } }

/* ─── Typography helpers ────────────────────────────────────── */
.display {
  font-family: var(--f-display);
  font-weight: 700;
  letter-spacing: -.03em;
  line-height: 1.06;
}
.grad-text {
  background: linear-gradient(100deg, var(--txt) 6%, var(--blue-hi) 48%, var(--cyan) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.mono { font-family: var(--f-mono); }
.sub  { color: var(--txt-2); }

/* ─── Nav (shared) ──────────────────────────────────────────── */
.nav2040 {
  position: fixed;
  top: 14px; left: 50%;
  transform: translateX(-50%);
  z-index: 1000;
  width: min(1140px, calc(100% - 28px));
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .6rem .8rem .6rem 1.25rem;
  border-radius: 999px;
  background: var(--nav-bg);
  border: 1px solid var(--glass-brd);
  backdrop-filter: blur(24px) saturate(1.6);
  -webkit-backdrop-filter: blur(24px) saturate(1.6);
  box-shadow: var(--glass-inset), 0 10px 34px -14px rgba(2,8,30,.5);
}
.nav2040 .brand {
  display: flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--f-display);
  font-weight: 700;
  font-size: 1.06rem;
  letter-spacing: -.02em;
}
.nav2040 .brand .orb {
  width: 26px; height: 26px;
  border-radius: 50%;
  background:
    radial-gradient(circle at 32% 28%, rgba(255,255,255,.85) 0%, transparent 32%),
    conic-gradient(from 210deg, var(--blue-hi), var(--cyan), var(--violet), var(--blue-hi));
  box-shadow: var(--glow-sm);
}
.nav2040 .brand .brand-logo {
  width: 26px; height: 26px;
  object-fit: contain;
  filter: drop-shadow(0 0 6px rgba(56,189,248,.35));
}
.nav2040 .links {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  font-size: .9rem;
  color: var(--txt-2);
}
.nav2040 .links a { transition: color .25s; }
.nav2040 .links a:hover { color: var(--txt); }
.nav2040 .actions { display: flex; align-items: center; gap: .55rem; }

/* Theme toggle */
.theme-toggle {
  width: 40px; height: 40px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 1px solid var(--glass-brd);
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  font-size: 1.05rem;
  line-height: 1;
  transition: all .3s var(--ease);
}
.theme-toggle:hover {
  border-color: var(--glass-brd-hi);
  transform: rotate(18deg) scale(1.06);
  box-shadow: var(--glow-sm);
}
.theme-toggle .ico-sun  { display: none; }
.theme-toggle .ico-moon { display: block; }
:root[data-theme="light"] .theme-toggle .ico-sun  { display: block; }
:root[data-theme="light"] .theme-toggle .ico-moon { display: none; }

/* Language select */
.lang-select {
  appearance: none;
  -webkit-appearance: none;
  padding: .45rem 1.75rem .45rem .85rem;
  border-radius: 999px;
  border: 1px solid var(--glass-brd);
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: var(--txt);
  font-family: var(--f-mono);
  font-size: .78rem;
  cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--txt-2) 50%),
                    linear-gradient(135deg, var(--txt-2) 50%, transparent 50%);
  background-position: calc(100% - 15px) 55%, calc(100% - 10px) 55%;
  background-size: 5px 5px;
  background-repeat: no-repeat;
  transition: border-color .3s;
}
.lang-select:hover { border-color: var(--glass-brd-hi); }
.lang-select option { background: var(--bg2); color: var(--txt); }

/* Mobile nav */
.nav-burger { display: none; }
.nav-mobile { display: none; }
@media (max-width: 880px) {
  .nav2040 .links { display: none; }
  .nav-burger {
    display: grid;
    place-items: center;
    width: 40px; height: 40px;
    border-radius: 50%;
    border: 1px solid var(--glass-brd);
    background: var(--glass);
    font-size: 1.15rem;
  }
  .nav-mobile {
    position: fixed;
    top: 76px; left: 50%;
    transform: translateX(-50%) translateY(-8px);
    width: min(1140px, calc(100% - 28px));
    z-index: 999;
    display: flex;
    flex-direction: column;
    gap: .25rem;
    padding: .8rem;
    border-radius: var(--r);
    background: var(--nav-bg);
    border: 1px solid var(--glass-brd);
    backdrop-filter: blur(24px) saturate(1.6);
    -webkit-backdrop-filter: blur(24px) saturate(1.6);
    opacity: 0;
    pointer-events: none;
    transition: all .3s var(--ease);
  }
  .nav-mobile.open { opacity: 1; pointer-events: auto; transform: translateX(-50%) translateY(0); }
  .nav-mobile a {
    padding: .7rem 1rem;
    border-radius: var(--r-sm);
    color: var(--txt-2);
    font-size: .95rem;
  }
  .nav-mobile a:hover { background: var(--glass-strong); color: var(--txt); }
}

/* ─── Sections & layout ─────────────────────────────────────── */
.wrap { width: min(1140px, calc(100% - 40px)); margin: 0 auto; }
.section { padding: 6.5rem 0; }
.section-head { max-width: 680px; margin-bottom: 3.2rem; }
.section-head .chip { margin-bottom: 1.1rem; }
.section-head h2 {
  font-family: var(--f-display);
  font-size: clamp(1.7rem, 3.6vw, 2.6rem);
  font-weight: 700;
  letter-spacing: -.03em;
  line-height: 1.12;
  margin-bottom: .9rem;
}
.section-head p { color: var(--txt-2); font-size: 1.05rem; }

/* ─── Code blocks ───────────────────────────────────────────── */
.codeblock {
  background: var(--code-bg);
  border: 1px solid var(--glass-brd);
  border-radius: var(--r-sm);
  padding: 1.1rem 1.25rem;
  font-family: var(--f-mono);
  font-size: .82rem;
  line-height: 1.75;
  color: #cfe0ff;
  overflow-x: auto;
  white-space: pre;
}
.codeblock .c-dim { color: #5c6f96; }
.codeblock .c-blu { color: #7db3ff; }
.codeblock .c-cyn { color: #67e8f9; }
.codeblock .c-ok  { color: #6ee7b7; }
.codeblock .c-wrn { color: #fcd34d; }

/* ─── Forms ─────────────────────────────────────────────────── */
.field label {
  display: block;
  font-family: var(--f-display);
  font-weight: 600;
  font-size: .92rem;
  margin-bottom: .45rem;
}
.field .hint { font-size: .8rem; color: var(--txt-3); margin-top: .35rem; }
.input, textarea.input {
  width: 100%;
  padding: .78rem 1rem;
  border-radius: var(--r-sm);
  border: 1px solid var(--glass-brd);
  background: var(--glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  color: var(--txt);
  font-family: var(--f-text);
  font-size: .95rem;
  transition: border-color .25s, box-shadow .25s;
}
.input:focus, textarea.input:focus {
  outline: none;
  border-color: var(--blue-hi);
  box-shadow: 0 0 0 3px rgba(59,130,246,.18);
}
textarea.input { resize: vertical; min-height: 90px; font-family: var(--f-mono); font-size: .86rem; }

/* Range slider */
input[type="range"].range {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--blue-hi) var(--fill, 50%), var(--glass-brd) var(--fill, 50%));
  outline: none;
}
input[type="range"].range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px; height: 20px;
  border-radius: 50%;
  background: radial-gradient(circle at 32% 30%, #fff 0%, var(--blue-hi) 55%, var(--blue-lo) 100%);
  border: 1px solid rgba(255,255,255,.55);
  box-shadow: var(--glow-sm);
  cursor: pointer;
}
input[type="range"].range::-moz-range-thumb {
  width: 20px; height: 20px;
  border-radius: 50%;
  background: radial-gradient(circle at 32% 30%, #fff 0%, var(--blue-hi) 55%, var(--blue-lo) 100%);
  border: 1px solid rgba(255,255,255,.55);
  box-shadow: var(--glow-sm);
  cursor: pointer;
}

/* Toggle checkbox pill */
.check-pill {
  display: flex;
  align-items: flex-start;
  gap: .8rem;
  padding: .9rem 1.05rem;
  border-radius: var(--r-sm);
  border: 1px solid var(--glass-brd);
  background: var(--glass);
  cursor: pointer;
  transition: all .25s var(--ease);
}
.check-pill:hover { border-color: var(--glass-brd-hi); }
.check-pill input { display: none; }
.check-pill .box {
  flex: none;
  width: 20px; height: 20px;
  margin-top: 2px;
  border-radius: 6px;
  border: 1.5px solid var(--glass-brd-hi);
  display: grid;
  place-items: center;
  font-size: .72rem;
  color: transparent;
  transition: all .2s;
}
.check-pill input:checked + .box {
  background: linear-gradient(135deg, var(--blue-hi), var(--blue-lo));
  border-color: transparent;
  color: #fff;
}
.check-pill.on { border-color: var(--blue-hi); background: var(--glass-strong); box-shadow: var(--glow-sm); }
.check-pill .t { font-weight: 600; font-size: .92rem; }
.check-pill .d { font-size: .8rem; color: var(--txt-3); line-height: 1.45; }

/* Selectable option card */
.opt-card {
  position: relative;
  display: block;
  padding: 1.15rem 1.25rem;
  border-radius: var(--r);
  border: 1px solid var(--glass-brd);
  background: var(--glass);
  backdrop-filter: blur(14px) saturate(1.4);
  -webkit-backdrop-filter: blur(14px) saturate(1.4);
  cursor: pointer;
  text-align: left;
  width: 100%;
  transition: all .3s var(--ease);
}
.opt-card:hover { border-color: var(--glass-brd-hi); transform: translateY(-2px); }
.opt-card.sel {
  border-color: var(--blue-hi);
  background: var(--glass-strong);
  box-shadow: var(--glass-inset), var(--glow-sm);
}
.opt-card.sel::after {
  content: '✓';
  position: absolute;
  top: .8rem; right: .95rem;
  width: 22px; height: 22px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: .7rem;
  color: #fff;
  background: linear-gradient(135deg, var(--blue-hi), var(--blue-lo));
}
.opt-card .ic { font-size: 1.35rem; margin-bottom: .5rem; display: block; }
.opt-card .t { font-family: var(--f-display); font-weight: 600; font-size: 1rem; margin-bottom: .3rem; }
.opt-card .d { font-size: .82rem; color: var(--txt-2); line-height: 1.5; }

/* ─── Footer ────────────────────────────────────────────────── */
.footer2040 {
  margin-top: 4rem;
  padding: 3.2rem 0 2.6rem;
  border-top: 1px solid var(--glass-brd);
  background: linear-gradient(to bottom, transparent, rgba(59,130,246,.05));
}
.footer2040 .cols {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem 4rem;
  justify-content: space-between;
  margin-bottom: 2.2rem;
}
.footer2040 h4 {
  font-family: var(--f-display);
  font-size: .82rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--txt-3);
  margin-bottom: .9rem;
}
.footer2040 a { display: block; color: var(--txt-2); font-size: .9rem; padding: .22rem 0; transition: color .25s; }
.footer2040 a:hover { color: var(--blue-hi); }
.footer2040 .fine { color: var(--txt-3); font-size: .8rem; font-family: var(--f-mono); }

/* ─── Utility ───────────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }

.scroll-top {
  position: fixed;
  right: 22px; bottom: 22px;
  z-index: 900;
  width: 46px; height: 46px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 1.1rem;
  background: var(--glass-strong);
  border: 1px solid var(--glass-brd);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  opacity: 0;
  pointer-events: none;
  transition: all .35s var(--ease);
}
.scroll-top.show { opacity: 1; pointer-events: auto; }
.scroll-top:hover { border-color: var(--glass-brd-hi); transform: translateY(-3px); box-shadow: var(--glow-sm); }
