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

:root {
  --black:    #0f0f0f;
  --white:    #ffffff;
  --bg:       #ffffff;
  --bg-alt:   #f8f9fb;
  --grey-100: #f3f4f6;
  --grey-200: #e5e7eb;
  --grey-400: #9ca3af;
  --grey-600: #6b7280;
  --grey-800: #1f2937;
  --accent:      #6366f1;
  --accent-dark: #4f46e5;
  --accent-light: rgba(99,102,241,0.08);
  --radius: 14px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--black);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, .logo {
  font-family: 'Sora', 'Inter', sans-serif;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 28px;
}

/* NAV */
nav {
  position: sticky;
  top: 0;
  background: rgba(255,255,255,0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--grey-200);
  z-index: 100;
}
.nav-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 16px 28px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--accent);
  text-decoration: none;
}
.brand { color: var(--accent); }
.logo img {
  width: 28px;
  height: 28px;
}

/* BUTTONS */
.btn {
  display: inline-block;
  padding: 11px 22px;
  border-radius: 999px;
  font-size: 0.875rem;
  font-weight: 600;
  font-family: inherit;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: transform 0.15s, box-shadow 0.15s, opacity 0.15s;
  letter-spacing: -0.01em;
}
.btn:hover { opacity: 0.88; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn-sm { padding: 8px 18px; font-size: 0.8rem; }
.btn-primary {
  background: var(--accent);
  color: var(--white);
  box-shadow: 0 2px 14px rgba(99,102,241,0.35);
}
.btn-primary:hover {
  box-shadow: 0 4px 22px rgba(99,102,241,0.45);
}

/* HERO */
.hero {
  padding: 120px 0 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -80px;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 600px;
  background: radial-gradient(ellipse at center, rgba(99,102,241,0.09) 0%, transparent 68%);
  pointer-events: none;
}
.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.4rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.07;
  margin-bottom: 24px;
  color: var(--black);
}
.hero h1 .highlight {
  color: var(--accent);
}
.hero-image {
  margin-top: 64px;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}
.hero-image img {
  width: 100%;
  height: auto;
  border-radius: 16px;
  box-shadow: 0 24px 80px rgba(0,0,0,0.12);
}
.subtitle {
  font-size: 1.1rem;
  color: var(--grey-600);
  max-width: 520px;
  margin: 0 auto 44px;
  line-height: 1.65;
  font-weight: 400;
}

/* DEMOS */
.demos {
  background: var(--bg-alt);
  padding: 96px 0;
  text-align: center;
  border-top: 1px solid var(--grey-200);
  border-bottom: 1px solid var(--grey-200);
}
.demos h2, .how h2, .signup h2 {
  font-size: clamp(1.7rem, 3.5vw, 2.4rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  margin-bottom: 12px;
  color: var(--black);
}
.section-sub {
  color: var(--grey-400);
  margin-bottom: 52px;
  font-size: 1rem;
}
.demo-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  text-align: left;
}
.demo-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  border: 1px solid var(--grey-200);
  box-shadow: 0 2px 12px rgba(0,0,0,0.05);
  transition: box-shadow 0.22s, transform 0.22s;
  display: flex;
  flex-direction: column;
}
.demo-card:hover {
  box-shadow: 0 12px 40px rgba(99,102,241,0.13);
  transform: translateY(-4px);
}
.demo-card-img {
  background: var(--white);
  border-bottom: 1px solid var(--grey-200);
  aspect-ratio: 460 / 716;
  overflow: hidden;
}
.demo-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
  display: block;
}
.demo-card-text {
  padding: 18px 20px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
}
.demo-card-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 14px;
  background: rgba(99,102,241,0.10);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}
.demo-card-icon svg {
  width: 24px;
  height: 24px;
}
.demo-card-text h3 {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--black);
  letter-spacing: -0.02em;
  margin-bottom: 4px;
  line-height: 1.3;
}
.demo-card-text p {
  font-size: 0.825rem;
  color: var(--grey-600);
  line-height: 1.6;
  margin: 0;
}
@media (max-width: 720px) {
  .demo-grid { grid-template-columns: 1fr; max-width: 380px; margin: 0 auto; }
}

/* HOW IT WORKS */
.how {
  padding: 96px 0;
  text-align: center;
  background: var(--bg);
}
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 36px;
  margin-top: 52px;
  text-align: left;
}
.step-num {
  width: 38px;
  height: 38px;
  background: var(--accent);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.875rem;
  margin-bottom: 16px;
  box-shadow: 0 2px 12px rgba(99,102,241,0.3);
}
.step h3 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}
.step p {
  font-size: 0.875rem;
  color: var(--grey-600);
  line-height: 1.65;
}

/* SIGNUP */
.signup {
  background: var(--grey-800);
  color: var(--white);
  padding: 96px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.signup::before {
  content: '';
  position: absolute;
  top: -60px;
  left: 50%;
  transform: translateX(-50%);
  width: 700px;
  height: 400px;
  background: radial-gradient(ellipse at center, rgba(99,102,241,0.2) 0%, transparent 70%);
  pointer-events: none;
}
.signup h2 { color: var(--white); }
.signup > .container > p {
  color: var(--grey-400);
  margin: 14px auto 40px;
  max-width: 460px;
  font-size: 1rem;
}
.input-row {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}
.input-row input {
  padding: 13px 20px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.07);
  color: var(--white);
  font-size: 0.95rem;
  font-family: inherit;
  width: 230px;
  outline: none;
  transition: border-color 0.15s, background 0.15s;
  letter-spacing: -0.01em;
}
.input-row input::placeholder { color: rgba(255,255,255,0.3); }
.input-row input:focus {
  border-color: var(--accent);
  background: rgba(99,102,241,0.1);
}
.form-message {
  margin-top: 18px;
  font-size: 0.875rem;
  min-height: 1.4em;
}
.form-message.success { color: #34d399; }
.form-message.error   { color: #f87171; }

/* FOOTER */
footer {
  padding: 44px 0;
  border-top: 1px solid var(--grey-200);
  text-align: center;
  background: var(--bg);
}
footer p {
  font-size: 0.825rem;
  color: var(--grey-400);
  max-width: 580px;
  margin: 0 auto 8px;
  line-height: 1.6;
}
.footer-small { font-size: 0.75rem; }
footer a { color: var(--grey-400); text-decoration: none; }
footer a:hover { color: var(--grey-600); text-decoration: underline; }

@media (max-width: 600px) {
  .hero { padding: 80px 0 64px; }
  .demos, .how, .signup { padding: 72px 0; }
  .input-row input { width: 100%; }
  .input-row .btn { width: 100%; text-align: center; }
}