/* ===========================
   MindVault — Landing Page
   style.css
   =========================== */

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: #0f0f0f;
  color: #f5f5f5;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: inherit;
  text-decoration: none;
}

/* ---------- TOKENS ---------- */
:root {
  --indigo: #6366f1;
  --indigo-light: #818cf8;
  --indigo-dim: rgba(99, 102, 241, 0.12);
  --indigo-glow: rgba(99, 102, 241, 0.25);
  --bg: #0f0f0f;
  --bg-surface: #161616;
  --bg-card: #1a1a1a;
  --bg-card-hover: #1f1f1f;
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --text-primary: #f5f5f5;
  --text-secondary: #a1a1aa;
  --text-muted: #71717a;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition: 200ms ease;
}

/* ---------- LAYOUT ---------- */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- SCROLL FADE ---------- */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- NAV ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(15, 15, 15, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav__inner {
  display: flex;
  align-items: center;
  height: 60px;
}

.nav__logo {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav__logo::before {
  content: '🧠';
  font-size: 1.2rem;
}

/* ---------- HERO ---------- */
.hero {
  padding: 100px 0 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  z-index: 1;
  max-width: 760px;
  margin: 0 auto;
}

.hero__badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 100px;
  background: var(--indigo-dim);
  border: 1px solid rgba(99, 102, 241, 0.3);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--indigo-light);
  margin-bottom: 28px;
}

.hero__headline {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.hero__headline em {
  font-style: normal;
  color: var(--indigo-light);
}

.hero__subheadline {
  font-size: clamp(1rem, 2vw, 1.15rem);
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero__social-proof {
  margin-top: 20px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.hero__social-proof strong {
  color: var(--text-secondary);
}

/* ---------- WAITLIST FORM ---------- */
.waitlist-form__group {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: 480px;
  margin: 0 auto;
}

.waitlist-form__input {
  flex: 1;
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  font-family: inherit;
  font-size: 0.95rem;
  color: var(--text-primary);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.waitlist-form__input::placeholder {
  color: var(--text-muted);
}

.waitlist-form__input:focus {
  border-color: var(--indigo);
  box-shadow: 0 0 0 3px var(--indigo-glow);
}

.waitlist-form__btn {
  padding: 14px 28px;
  background: var(--indigo);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  white-space: nowrap;
}

.waitlist-form__btn:hover {
  background: var(--indigo-light);
  box-shadow: 0 4px 20px var(--indigo-glow);
}

.waitlist-form__btn:active {
  transform: scale(0.98);
}

.waitlist-form__message {
  margin-top: 8px;
  font-size: 0.875rem;
  min-height: 1.4em;
  text-align: center;
}

.waitlist-form__message--success {
  color: #4ade80;
}

.waitlist-form__message--error {
  color: #f87171;
}

.waitlist-form__message--info {
  color: var(--indigo-light);
}

/* ---------- SECTION COMMON ---------- */
.section-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  text-align: center;
  margin-bottom: 12px;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  text-align: center;
  margin-bottom: 56px;
}

/* ---------- PROBLEMS ---------- */
.problems {
  padding: 100px 0;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.problems .section-title {
  margin-bottom: 48px;
}

.problems__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.problem-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: border-color var(--transition), transform var(--transition);
}

.problem-card:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

.problem-card__icon {
  font-size: 1.8rem;
  margin-bottom: 14px;
  line-height: 1;
}

.problem-card__title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 10px;
  line-height: 1.4;
}

.problem-card__body {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ---------- HOW IT WORKS ---------- */
.how-it-works {
  padding: 100px 0;
}

.steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 640px;
  margin: 0 auto;
}

.step {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 28px 0;
}

.step__connector {
  width: 2px;
  height: 32px;
  background: linear-gradient(to bottom, var(--indigo), transparent);
  margin-left: 27px;
  opacity: 0.4;
}

.step__number {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--indigo-dim);
  border: 1px solid rgba(99, 102, 241, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--indigo-light);
  letter-spacing: 0.05em;
}

.step__content {
  padding-top: 8px;
}

.step__title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.step__body {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ---------- WAITLIST SECTION ---------- */
.waitlist-section {
  padding: 100px 0;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  text-align: center;
}

.waitlist-section__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.waitlist-section__subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 36px;
}

.waitlist-section__privacy {
  margin-top: 16px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ---------- FOOTER ---------- */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer__text {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ---------- DESKTOP ---------- */
@media (min-width: 640px) {
  .waitlist-form__group {
    flex-direction: row;
  }
}

@media (min-width: 768px) {
  .problems__grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .steps {
    gap: 0;
  }

  .step {
    padding: 32px 0;
  }
}

@media (min-width: 1024px) {
  .hero {
    padding: 130px 0 100px;
  }

  .problems {
    padding: 120px 0;
  }

  .how-it-works {
    padding: 120px 0;
  }

  .waitlist-section {
    padding: 120px 0;
  }
}