/* ================================================================
   CSS VARIABLES & RESET
   ================================================================ */
:root {
  --bg:           #f8f9fa;
  --surface:      #ffffff;
  --surface2:     #f1f3f5;
  --surface3:     #e9ecef;
  --border:       #dee2e6;
  --accent:       #5c7cfa;
  --accent-dim:   rgba(92,124,250,.08);
  --accent-hover: #4c6ef5;
  --text:         #212529;
  --text2:        #6c757d;
  --success:      #37b24d;
  --warning:      #f59f00;
  --danger:       #f03e3e;
  --danger-dim:   rgba(240,62,62,.08);
  --success-dim:  rgba(55,178,77,.08);
  --r:            8px;
  --r-lg:         14px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
}

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

/* ================================================================
   HEADER
   ================================================================ */
header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 32px;
  height: 60px;
  display: flex;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  box-shadow: 0 1px 3px rgba(0,0,0,.05);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -.3px;
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--accent);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
}

.logo span {
  color: var(--accent);
}

nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 6px;
}

nav > div {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link {
  padding: 7px 14px;
  border-radius: var(--r);
  color: var(--text2);
  font-size: 14px;
  font-weight: 500;
  transition: color .15s, background .15s;
}

.nav-link:hover {
  color: var(--text);
  background: var(--surface2);
}

.btn-login {
  padding: 7px 18px;
  border-radius: var(--r);
  background: var(--accent);
  color: #fff;
  border: none;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .2px;
  transition: background .15s, transform .1s;
  margin-left: 8px;
}

.btn-login:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.back-link {
  margin-left: auto;
  font-size: 13px;
  color: var(--text2);
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: var(--r);
  transition: color .15s, background .15s;
}

.back-link:hover {
  color: var(--text);
  background: var(--surface2);
}

/* ================================================================
   HERO SECTION
   ================================================================ */
.hero {
  padding: 90px 32px 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 50% at 50% -10%, rgba(92,124,250,.12) 0%, transparent 70%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 14px;
  background: var(--accent-dim);
  border: 1px solid rgba(92,124,250,.2);
  border-radius: 20px;
  font-size: 12px;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: .5px;
  text-transform: uppercase;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(32px, 6vw, 58px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -1.5px;
  max-width: 760px;
  margin: 0 auto 20px;
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: 18px;
  color: var(--text2);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-primary {
  padding: 13px 28px;
  background: var(--accent);
  color: #fff;
  border-radius: var(--r);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .1px;
  transition: background .15s, transform .1s, box-shadow .15s;
  box-shadow: 0 4px 20px rgba(92,124,250,.25);
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(92,124,250,.35);
}

.btn-secondary {
  padding: 13px 28px;
  background: var(--surface2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--r);
  font-size: 15px;
  font-weight: 600;
  transition: background .15s, transform .1s, border-color .15s;
}

.btn-secondary:hover {
  background: var(--surface3);
  border-color: var(--accent);
  transform: translateY(-2px);
}

/* ================================================================
   SECTION GENERAL
   ================================================================ */
section {
  padding: 72px 32px;
}

.section-label {
  font-size: 12px;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  text-align: center;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(22px, 3.5vw, 32px);
  font-weight: 800;
  letter-spacing: -.5px;
  text-align: center;
  margin-bottom: 12px;
}

.section-sub {
  color: var(--text2);
  text-align: center;
  max-width: 480px;
  margin: 0 auto 52px;
  font-size: 15px;
}

/* ================================================================
   FEATURES GRID
   ================================================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  max-width: 1080px;
  margin: 0 auto;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 28px 24px;
  transition: border-color .2s, transform .2s, box-shadow .2s;
}

.feature-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: 0 8px 32px rgba(0,0,0,.08);
}

.feature-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  margin-bottom: 16px;
}

.feature-card h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--text2);
  font-size: 14px;
  line-height: 1.65;
}

/* ================================================================
   HOW IT WORKS
   ================================================================ */
.how-section {
  background: var(--surface);
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0;
  max-width: 900px;
  margin: 0 auto;
  position: relative;
}

.steps::before {
  content: '';
  position: absolute;
  top: 28px;
  left: calc(16.6% + 24px);
  right: calc(16.6% + 24px);
  height: 1px;
  background: var(--border);
}

.step {
  text-align: center;
  padding: 0 20px;
}

.step-num {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--surface2);
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 800;
  color: var(--accent);
  margin: 0 auto 16px;
  position: relative;
  z-index: 1;
}

.step h4 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 8px;
}

.step p {
  font-size: 13px;
  color: var(--text2);
}

/* ================================================================
   TECH STACK
   ================================================================ */
.tech-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  max-width: 700px;
  margin: 0 auto;
}

.tech-chip {
  padding: 8px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text2);
  display: flex;
  align-items: center;
  gap: 7px;
}

.tech-chip span {
  font-size: 16px;
}

/* ================================================================
   CTA BANNER
   ================================================================ */
.cta-section {
  background: linear-gradient(135deg, rgba(92,124,250,.08) 0%, rgba(55,178,77,.05) 100%);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  text-align: center;
}

.cta-section h2 {
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 800;
  letter-spacing: -.5px;
  margin-bottom: 12px;
}

.cta-section p {
  color: var(--text2);
  margin-bottom: 32px;
  font-size: 16px;
}

/* ================================================================
   FOOTER
   ================================================================ */
footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 28px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

footer .logo {
  font-size: 15px;
}

footer p {
  font-size: 13px;
  color: var(--text2);
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  font-size: 13px;
  color: var(--text2);
  transition: color .15s;
}

.footer-links a:hover {
  color: var(--text);
}

/* ================================================================
   RESPONSIVE
   ================================================================ */
@media (max-width: 600px) {
  header {
    padding: 0 16px;
  }
  .hero {
    padding: 60px 16px 56px;
  }
  section {
    padding: 56px 16px;
  }
  .steps::before {
    display: none;
  }
  footer {
    padding: 20px 16px;
    flex-direction: column;
    align-items: flex-start;
  }
}