/* ===== CSS Variables ===== */
:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-primary-light: #3b82f6;
  --color-secondary: #64748b;
  --color-text: #1e293b;
  --color-text-light: #64748b;
  --color-background: #ffffff;
  --color-background-alt: #f8fafc;
  --color-border: #e2e8f0;
  --color-success: #10b981;

  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

img {
  max-width: 100%;
  height: auto;
}

/* ===== Container ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: inherit;
  font-weight: 500;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-sm {
  padding: 8px 16px;
  font-size: 14px;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 16px;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background-color: var(--color-background-alt);
  border-color: var(--color-secondary);
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text);
}

.logo-icon {
  width: 28px;
  height: 28px;
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a:not(.btn) {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text-light);
  transition: color 0.2s ease;
}

.nav-links a:not(.btn):hover {
  color: var(--color-text);
}

/* ===== Hero Section ===== */
.hero {
  padding: 160px 0 100px;
  text-align: center;
  background: linear-gradient(180deg, var(--color-background-alt) 0%, var(--color-background) 100%);
}

.hero-title {
  font-size: clamp(40px, 6vw, 64px);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 20px;
  color: var(--color-text-light);
  max-width: 600px;
  margin: 0 auto 40px;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-image {
  margin-top: 60px;
}

.device-mockup {
  max-width: 800px;
  margin: 0 auto;
  background: linear-gradient(135deg, #e0e7ff 0%, #c7d2fe 100%);
  border-radius: var(--radius-xl);
  padding: 20px;
  box-shadow: var(--shadow-xl);
}

.mockup-screen {
  background: white;
  border-radius: var(--radius-md);
  padding: 24px;
  min-height: 300px;
}

.mockup-header {
  height: 24px;
  background: var(--color-background-alt);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  width: 40%;
}

.mockup-row {
  height: 48px;
  background: var(--color-background-alt);
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
}

.mockup-row:last-child {
  margin-bottom: 0;
}

/* ===== Section Styles ===== */
.section-title {
  font-size: clamp(32px, 4vw, 42px);
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.section-subtitle {
  font-size: 18px;
  color: var(--color-text-light);
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

/* ===== Features Section ===== */
.features {
  padding: 100px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 32px;
}

.feature-card {
  padding: 32px;
  background: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: all 0.3s ease;
}

.feature-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-icon svg {
  width: 24px;
  height: 24px;
  color: var(--color-primary);
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--color-text-light);
  line-height: 1.6;
}

/* ===== How It Works Section ===== */
.how-it-works {
  padding: 100px 0;
  background-color: var(--color-background-alt);
}

.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.step {
  flex: 1;
  min-width: 250px;
  max-width: 320px;
  text-align: center;
  padding: 24px;
}

.step-number {
  width: 56px;
  height: 56px;
  background: var(--color-primary);
  color: white;
  font-size: 24px;
  font-weight: 700;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
}

.step h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
}

.step p {
  color: var(--color-text-light);
  line-height: 1.6;
}

.step-connector {
  width: 60px;
  height: 2px;
  background: var(--color-border);
  margin-top: 52px;
}

/* ===== CTA Section ===== */
.cta {
  padding: 100px 0;
  text-align: center;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: white;
}

.cta h2 {
  font-size: clamp(32px, 4vw, 42px);
  font-weight: 700;
  margin-bottom: 16px;
}

.cta > .container > p {
  font-size: 18px;
  opacity: 0.9;
  max-width: 500px;
  margin: 0 auto 40px;
}

.cta-form {
  display: flex;
  gap: 12px;
  max-width: 480px;
  margin: 0 auto 20px;
  flex-wrap: wrap;
  justify-content: center;
}

.cta-form input {
  flex: 1;
  min-width: 240px;
  padding: 14px 20px;
  font-size: 16px;
  font-family: inherit;
  border: none;
  border-radius: var(--radius-md);
  outline: none;
}

.cta-form input::placeholder {
  color: var(--color-text-light);
}

.cta-form .btn {
  background: var(--color-text);
  color: white;
}

.cta-form .btn:hover {
  background: #0f172a;
}

.cta-note {
  font-size: 14px;
  opacity: 0.8;
}

/* ===== Footer ===== */
.footer {
  padding: 60px 0 30px;
  background: var(--color-text);
  color: white;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .logo {
  color: white;
  margin-bottom: 12px;
}

.footer-brand .logo-icon {
  color: white;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 14px;
}

.footer-links {
  display: flex;
  gap: 32px;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.6);
  font-size: 14px;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: white;
}

.footer-bottom {
  padding-top: 30px;
  text-align: center;
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.4);
  font-size: 14px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-links {
    gap: 20px;
  }

  .nav-links a:not(.btn) {
    display: none;
  }

  .hero {
    padding: 140px 0 80px;
  }

  .hero-subtitle {
    font-size: 18px;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .step-connector {
    display: none;
  }

  .steps {
    flex-direction: column;
    align-items: center;
  }

  .cta-form {
    flex-direction: column;
    align-items: stretch;
  }

  .cta-form input {
    min-width: unset;
  }

  .footer-content {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .hero-cta {
    flex-direction: column;
    align-items: stretch;
  }

  .btn-lg {
    padding: 16px 24px;
  }
}