/* ============================================
   Prepwise Learning | Modern, elegant, minimal
   ============================================ */

:root {
  --bg: #0a0e1a;
  --bg-soft: #0f1424;
  --surface: #ffffff;
  --surface-2: #f7f8fb;
  --ink: #0a0e1a;
  --ink-2: #1f2937;
  --muted: #6b7280;
  --line: #e6e8ef;
  --accent: #6366f1;
  --accent-2: #8b5cf6;
  --accent-3: #22d3ee;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04), 0 2px 8px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 8px 30px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 30px 80px rgba(15, 23, 42, 0.18);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "SF Pro Display",
    "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--surface-2);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  line-height: 1.65;
  letter-spacing: -0.01em;

  /* Tamper-resistance: block selection / drag / context menu UI */
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
  -webkit-touch-callout: none;
  -webkit-tap-highlight-color: transparent;
}

/* Allow selection inside form fields if any are added later */
input, textarea {
  -webkit-user-select: text;
  user-select: text;
}

/* Prevent image dragging / saving via drag */
img {
  -webkit-user-drag: none;
  -khtml-user-drag: none;
  -moz-user-drag: none;
  -o-user-drag: none;
  user-drag: none;
  pointer-events: auto;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}
a:hover { color: var(--accent-2); }

img { display: block; max-width: 100%; }

::selection { background: rgba(99, 102, 241, 0.18); color: var(--ink); }

/* ----- Top navigation ----- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(180%) blur(18px);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  background: rgba(255, 255, 255, 0.72);
  border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}
.nav-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 18px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.02em;
}
.brand img {
  width: 34px;
  height: 34px;
  border-radius: 9px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.4s var(--ease);
}
.brand:hover img { transform: rotate(-6deg) scale(1.05); }
.nav-links {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.nav-links a {
  position: relative;
  color: var(--ink-2);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: 999px;
  transition: all 0.25s var(--ease);
}
.nav-links a:hover {
  color: var(--ink);
  background: rgba(99, 102, 241, 0.08);
}

/* ----- Hero ----- */
.hero {
  position: relative;
  overflow: hidden;
  background: radial-gradient(1200px 600px at 50% -10%, rgba(99, 102, 241, 0.18), transparent 60%),
              radial-gradient(800px 500px at 90% 10%, rgba(34, 211, 238, 0.14), transparent 60%),
              linear-gradient(180deg, #ffffff 0%, #f7f8fb 100%);
  padding: 120px 28px 140px;
  text-align: center;
}
.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.55;
  pointer-events: none;
  animation: float 12s ease-in-out infinite;
}
.hero::before {
  width: 380px; height: 380px;
  background: radial-gradient(circle, #8b5cf6 0%, transparent 70%);
  top: -120px; left: -100px;
}
.hero::after {
  width: 420px; height: 420px;
  background: radial-gradient(circle, #22d3ee 0%, transparent 70%);
  bottom: -160px; right: -140px;
  animation-delay: -6s;
}
@keyframes float {
  0%, 100% { transform: translateY(0) translateX(0); }
  50% { transform: translateY(-30px) translateX(20px); }
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 760px;
  margin: 0 auto;
}
.hero img {
  width: 96px;
  height: 96px;
  border-radius: 22px;
  box-shadow: var(--shadow-lg);
  margin: 0 auto 28px;
  animation: rise 0.9s var(--ease) both;
}
.hero .eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(99, 102, 241, 0.1);
  margin-bottom: 22px;
  animation: rise 0.9s 0.1s var(--ease) both;
}
.hero h1 {
  font-size: clamp(38px, 6vw, 64px);
  line-height: 1.05;
  margin: 0 0 22px;
  font-weight: 800;
  letter-spacing: -0.035em;
  background: linear-gradient(180deg, #0a0e1a 0%, #475569 120%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: rise 0.9s 0.15s var(--ease) both;
}
.hero p.lead {
  font-size: 19px;
  color: var(--muted);
  max-width: 600px;
  margin: 0 auto 40px;
  animation: rise 0.9s 0.25s var(--ease) both;
}
.hero-cta {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  animation: rise 0.9s 0.35s var(--ease) both;
}

/* ----- Buttons ----- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 15px 28px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  color: #fff;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.01em;
  box-shadow: 0 10px 30px rgba(99, 102, 241, 0.35);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}
.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 40px rgba(99, 102, 241, 0.45);
  color: #fff;
}
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: none;
}
.btn-ghost:hover {
  background: #fff;
  color: var(--ink);
  border-color: var(--ink-2);
  box-shadow: var(--shadow-sm);
}

/* ----- Section heading ----- */
.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
}
.section-head .eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}
.section-head h2 {
  font-size: clamp(28px, 4vw, 40px);
  margin: 0;
  letter-spacing: -0.025em;
  font-weight: 800;
  line-height: 1.15;
}

/* ----- Features ----- */
.features {
  max-width: 1180px;
  margin: 0 auto;
  padding: 110px 28px;
}
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 22px;
}
.feature {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s var(--ease);
  overflow: hidden;
}
.feature::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.06), transparent 55%);
  opacity: 0;
  transition: opacity 0.4s var(--ease);
  pointer-events: none;
}
.feature:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(99, 102, 241, 0.3);
}
.feature:hover::after { opacity: 1; }
.feature-num {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.1em;
  margin-bottom: 16px;
}
.feature h3 {
  margin: 0 0 10px;
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.015em;
}
.feature p {
  color: var(--muted);
  font-size: 15px;
  margin: 0;
}

/* ----- Container / policy pages ----- */
.container {
  max-width: 820px;
  margin: 0 auto;
  padding: 80px 28px 100px;
  animation: rise 0.7s var(--ease) both;
}
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 56px 56px 48px;
  box-shadow: var(--shadow-sm);
}
h1.page-title {
  font-size: clamp(30px, 4vw, 42px);
  margin: 0 0 10px;
  font-weight: 800;
  letter-spacing: -0.03em;
}
.updated {
  color: var(--muted);
  font-size: 14px;
  margin-bottom: 36px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}
.policy h2 {
  font-size: 19px;
  margin: 38px 0 12px;
  color: var(--ink);
  font-weight: 700;
  letter-spacing: -0.015em;
}
.policy p,
.policy li {
  font-size: 15.5px;
  color: var(--ink-2);
}
.policy ul,
.policy ol { padding-left: 22px; }
.policy li { margin-bottom: 4px; }
.policy strong { color: var(--ink); font-weight: 600; }

/* ----- Footer ----- */
.footer {
  background: var(--bg);
  color: #94a3b8;
  padding: 64px 28px 48px;
  text-align: center;
  font-size: 14px;
  border-top: 1px solid rgba(255,255,255,0.04);
}
.footer-brand {
  color: #fff;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}
.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 0;
  margin-bottom: 24px;
}
.footer-links a {
  color: #cbd5e1;
  padding: 6px 16px;
  border-radius: 999px;
  font-size: 14px;
  transition: background 0.25s var(--ease), color 0.25s var(--ease);
}
.footer-links a:hover {
  background: rgba(255,255,255,0.06);
  color: #fff;
}
.footer-copy { color: #64748b; font-size: 13px; }

/* ----- Animations ----- */
@keyframes rise {
  0% { opacity: 0; transform: translateY(18px); }
  100% { opacity: 1; transform: translateY(0); }
}
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ----- Responsive ----- */
@media (max-width: 720px) {
  .hero { padding: 80px 22px 100px; }
  .features { padding: 70px 22px; }
  .card { padding: 32px 24px; }
  .container { padding: 48px 20px 70px; }
  .nav-inner { padding: 14px 20px; }
  .nav-links { gap: 2px; }
  .nav-links a { padding: 6px 10px; font-size: 13px; }
}