/* ============================================================================
 * AI Unite — Landing page styles
 * Modern SaaS look: dark background, electric blue accents, white typography,
 * responsive grid layouts, smooth scroll animations and hover effects.
 * ========================================================================== */

/* ----------------------------- Design tokens ----------------------------- */
:root {
  --bg: #070b15;
  --bg-alt: #0c1322;
  --panel: #121a2c;
  --panel-2: #18233a;
  --border: #233149;
  --text: #eef3fb;
  --muted: #9aa7c2;
  --accent: #2f8bff;       /* electric blue */
  --accent-2: #5e9bff;
  --accent-glow: rgba(47, 139, 255, 0.45);
  --danger: #ff5468;
  --success: #34d399;
  --radius: 14px;
  --maxw: 1180px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
}

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

html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; }

/* ------------------------------- Buttons --------------------------------- */
.btn {
  display: inline-block;
  border: none;
  border-radius: 10px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
  padding: 0.8rem 1.4rem;
  font-family: inherit;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), #6a5bff);
  color: #fff;
  box-shadow: 0 10px 30px var(--accent-glow);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 40px var(--accent-glow); }
.btn-primary:active { transform: translateY(0); }
.btn-lg { padding: 1rem 2rem; font-size: 1.1rem; }
.btn-block { width: 100%; }

/* ------------------------------- Navbar ---------------------------------- */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(7, 11, 21, 0.6);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: background 0.3s ease, border-color 0.3s ease;
}
.navbar.scrolled {
  background: rgba(7, 11, 21, 0.92);
  border-bottom-color: var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 70px; }

.logo { display: flex; align-items: center; gap: 0.55rem; font-weight: 800; font-size: 1.25rem; }
.logo-mark {
  display: grid; place-items: center;
  width: 36px; height: 36px; border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), #6a5bff);
  color: #fff; font-size: 0.95rem;
}
.logo-text { color: var(--text); }

.nav-links { display: flex; align-items: center; gap: 1.8rem; }
.nav-links a { color: var(--muted); font-weight: 500; transition: color 0.2s; }
.nav-links a:hover { color: var(--text); }
.nav-cta {
  background: var(--accent);
  color: #fff !important;
  padding: 0.55rem 1.1rem;
  border-radius: 9px;
}
.nav-cta:hover { background: var(--accent-2); }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; }
.nav-toggle span { width: 26px; height: 2px; background: var(--text); border-radius: 2px; transition: 0.3s; }

/* -------------------------------- Hero ----------------------------------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  z-index: 0;
}
.hero-overlay {
  position: absolute; inset: 0;
  background:
    radial-gradient(900px 500px at 20% 20%, rgba(47,139,255,0.22), transparent 60%),
    linear-gradient(180deg, rgba(7,11,21,0.7), rgba(7,11,21,0.96));
  z-index: 1;
}
.hero-content { position: relative; z-index: 2; text-align: center; padding: 6rem 1.25rem 4rem; }

.eyebrow {
  display: inline-block;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.35rem 1rem;
  margin-bottom: 1.4rem;
}

.hero h1 {
  font-size: clamp(2.2rem, 5.5vw, 4rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 1.2rem;
  background: linear-gradient(180deg, #fff, #c4d4f5);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.subhead { font-size: clamp(1.05rem, 2vw, 1.4rem); color: var(--muted); max-width: 720px; margin: 0 auto 2.2rem; }

.trust-badges {
  list-style: none;
  display: flex; flex-wrap: wrap; gap: 0.7rem; justify-content: center;
  margin-top: 2.5rem;
}
.trust-badges li {
  background: rgba(18, 26, 44, 0.7);
  border: 1px solid var(--border);
  padding: 0.5rem 0.9rem;
  border-radius: 999px;
  font-size: 0.85rem;
  color: var(--muted);
}

/* ------------------------------ Sections --------------------------------- */
.section { padding: 5.5rem 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 3rem; }
.section-head h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.8rem;
}
.section-head p { color: var(--muted); font-size: 1.1rem; }

/* --------------------------- AI tool cards ------------------------------- */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.4rem;
}
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.8rem;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}
.card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
  box-shadow: var(--shadow);
}
.card-logo {
  width: 60px; height: 60px;
  display: grid; place-items: center;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 14px;
  margin-bottom: 1.2rem;
}
.card-logo .plus { font-size: 2rem; font-weight: 800; color: var(--accent-2); }
.card h3 { font-size: 1.3rem; margin-bottom: 0.6rem; }
.card-desc { color: var(--text); margin-bottom: 0.9rem; }
.card-strength, .card-use { color: var(--muted); font-size: 0.9rem; margin-bottom: 0.4rem; }
.card-strength strong, .card-use strong { color: var(--accent-2); }
.card-more { border-style: dashed; }

/* ----------------------------- How it works ----------------------------- */
.steps-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 1.4rem; }
.step {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
}
.step-num {
  display: grid; place-items: center;
  width: 52px; height: 52px;
  margin: 0 auto 1rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), #6a5bff);
  color: #fff; font-weight: 800; font-size: 1.3rem;
}
.step h3 { margin-bottom: 0.5rem; }
.step p { color: var(--muted); }

/* ----------------------------- Register form ---------------------------- */
.register-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}
.register-copy h2 { font-size: clamp(1.8rem, 3.2vw, 2.5rem); margin-bottom: 1rem; }
.register-copy p { color: var(--muted); font-size: 1.1rem; margin-bottom: 1.5rem; }
.register-points { list-style: none; display: flex; flex-direction: column; gap: 0.6rem; color: var(--muted); }

.register-form {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 2.2rem;
  box-shadow: var(--shadow);
}
.register-form h3 { font-size: 1.5rem; margin-bottom: 1.4rem; }
.form-group { margin-bottom: 1.2rem; }
.form-group label { display: block; font-size: 0.9rem; font-weight: 500; margin-bottom: 0.45rem; color: var(--text); }
.form-group input {
  width: 100%;
  padding: 0.85rem 1rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--text);
  font-size: 1rem;
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.form-group input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-glow); }
.form-group input.invalid { border-color: var(--danger); }
.error { display: block; color: var(--danger); font-size: 0.82rem; margin-top: 0.35rem; min-height: 1rem; }

.form-message { margin-top: 1rem; font-size: 0.95rem; text-align: center; min-height: 1.2rem; }
.form-message.success { color: var(--success); }
.form-message.fail { color: var(--danger); }

/* -------------------------------- FAQ ------------------------------------ */
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 1rem; }
.faq-item {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.5rem 1.4rem;
}
.faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 1rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary h3 { font-size: 1.1rem; font-weight: 600; display: inline; }
.faq-item summary::after { content: '+'; font-size: 1.5rem; color: var(--accent-2); transition: transform 0.2s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { color: var(--muted); padding-bottom: 1rem; }

/* ------------------------------- Footer ---------------------------------- */
.footer { background: var(--bg-alt); border-top: 1px solid var(--border); padding-top: 3.5rem; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 2rem; padding-bottom: 2.5rem; }
.footer-brand p { color: var(--muted); margin: 1rem 0; max-width: 360px; }
.footer-badges { justify-content: flex-start; margin-top: 0; }
.footer-col h4 { margin-bottom: 1rem; font-size: 1rem; }
.footer-col a { display: block; color: var(--muted); margin-bottom: 0.6rem; transition: color 0.2s; }
.footer-col a:hover { color: var(--accent-2); }
.footer-bottom { border-top: 1px solid var(--border); padding: 1.4rem 1.25rem; text-align: center; color: var(--muted); font-size: 0.9rem; }

/* --------------------------- Scroll animations --------------------------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ------------------------------ Responsive ------------------------------- */
@media (max-width: 860px) {
  .register-wrap { grid-template-columns: 1fr; gap: 2rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; }

  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: 70px; right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 1.2rem;
    background: var(--bg-alt);
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    padding: 1.5rem;
    width: 220px;
    transform: translateX(110%);
    transition: transform 0.3s ease;
  }
  .nav-links.open { transform: translateX(0); }
}

@media (max-width: 520px) {
  .footer-grid { grid-template-columns: 1fr; }
  .section { padding: 4rem 0; }
}