@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --color-surface: #faf9f6;
  --color-surface-alt: #f0eee9;
  --color-surface-card: #ffffff;
  
  --color-on-surface: #181816;
  --color-on-surface-muted: #62625c;
  --color-on-surface-subtle: #96968e;
  
  --color-accent: #181816;
  --color-accent-hover: #333330;
  --color-accent-text: #ffffff;
  
  --border-subtle: rgba(24, 24, 22, 0.08);
  --border-hover: rgba(24, 24, 22, 0.22);
  
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --ease-newton: cubic-bezier(0.16, 1, 0.3, 1);
  --duration-interaction: 250ms;

  --shadow-nav: 0 4px 24px -6px rgba(0, 0, 0, 0.08), 0 0 1px rgba(0, 0, 0, 0.06);
  --shadow-card: 0 8px 30px rgba(0, 0, 0, 0.04);
}

/* Reset & Global */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  background-color: var(--color-surface);
  color: var(--color-on-surface);
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-color: var(--color-surface);
  color: var(--color-on-surface);
}

a {
  color: inherit;
  text-decoration: none;
  transition: opacity var(--duration-interaction) var(--ease-newton), color var(--duration-interaction) var(--ease-newton);
}

button {
  font-family: var(--font-sans);
  cursor: pointer;
  border: none;
  outline: none;
  background: none;
}

/* Header & Floating Navbar */
.header-wrapper {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  padding: 24px 16px;
  display: flex;
  justify-content: center;
  pointer-events: none;
}

.nav-container {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: 24px;
  height: 52px;
  padding: 0 8px 0 20px;
  border-radius: 14px;
  background: rgba(250, 249, 246, 0.82);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-nav);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.02em;
}

.brand-symbol {
  width: 18px;
  height: 20px;
  background-color: var(--color-accent);
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 2L2 22h20L12 2z'/%3E%3C/svg%3E") center/contain no-repeat;
  -webkit-mask: url("data:image/svg+xml,%3Csvg viewBox='0 0 24 24' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M12 2L2 22h20L12 2z'/%3E%3C/svg%3E") center/contain no-repeat;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link-item {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-on-surface);
  opacity: 0.7;
  padding: 6px 14px;
  border-radius: 8px;
}

.nav-link-item:hover {
  opacity: 1;
  background-color: rgba(24, 24, 22, 0.04);
}

.nav-divider {
  width: 1px;
  height: 20px;
  background-color: var(--border-subtle);
  margin: 0 4px;
}

/* Button Component */
.btn-newton {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  padding: 0 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: all var(--duration-interaction) var(--ease-newton);
  cursor: pointer;
  white-space: nowrap;
}

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

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

.btn-secondary {
  background-color: var(--color-surface-card);
  color: var(--color-on-surface);
  border: 1px solid var(--border-subtle);
}

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

/* Hero Section */
.hero-section {
  width: 100%;
  min-height: 90vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 140px 24px 80px 24px;
  position: relative;
}

.hero-title {
  font-size: 80px;
  line-height: 1.05;
  font-weight: 500;
  letter-spacing: -0.035em;
  margin-bottom: 24px;
  max-width: 900px;
}

.hero-subtitle {
  font-size: 20px;
  line-height: 1.55;
  color: var(--color-on-surface-muted);
  max-width: 580px;
  margin-bottom: 40px;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 80px;
}

/* Marquee Section */
.marquee-container {
  width: 100%;
  max-width: 1200px;
  overflow: hidden;
  position: relative;
  mask-image: linear-gradient(to right, transparent, black 15%, black 85%, transparent);
  -webkit-mask-image: linear-gradient(to right, transparent, black 15%, black 85%, transparent);
  padding: 20px 0;
}

.marquee-track {
  display: flex;
  align-items: center;
  gap: 48px;
  width: max-content;
  animation: marqueeScroll 25s linear infinite;
}

@keyframes marqueeScroll {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

.trusted-logo-text {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--color-on-surface-muted);
  opacity: 0.65;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Section Header */
.section-header {
  width: 100%;
  max-width: 1200px;
  margin-bottom: 48px;
}

.section-label {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-on-surface-subtle);
  margin-bottom: 12px;
}

.section-title {
  font-size: 40px;
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1.15;
  max-width: 720px;
}

/* Step Viewer ("What Newton Does") */
.section-workflow {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 100px 24px;
}

.workflow-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.workflow-preview-card {
  width: 100%;
  aspect-ratio: 4 / 3;
  background-color: var(--color-surface-card);
  border-radius: 16px;
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
  padding: 32px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  overflow: hidden;
}

.step-content-display {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.step-badge {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  padding: 4px 12px;
  border-radius: 20px;
  background-color: var(--color-surface-alt);
  color: var(--color-on-surface-muted);
}

.code-mock {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  background: var(--color-surface-alt);
  padding: 20px;
  border-radius: 12px;
  color: var(--color-on-surface);
  border: 1px solid var(--border-subtle);
}

/* Step Accordion List */
.step-accordion {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.step-item {
  display: flex;
  gap: 20px;
  cursor: pointer;
  padding: 16px 0;
  border-left: 2px solid var(--border-subtle);
  padding-left: 24px;
  transition: all var(--duration-interaction) var(--ease-newton);
}

.step-item.active {
  border-left-color: var(--color-accent);
}

.step-num {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-on-surface-subtle);
}

.step-item.active .step-num {
  color: var(--color-on-surface);
}

.step-title {
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 8px;
  letter-spacing: -0.02em;
}

.step-desc {
  font-size: 15px;
  line-height: 1.6;
  color: var(--color-on-surface-muted);
  display: none;
}

.step-item.active .step-desc {
  display: block;
}

/* Value Props Feature Grid */
.section-features {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 80px 24px 120px 24px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background-color: var(--color-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  transition: border-color var(--duration-interaction) var(--ease-newton);
}

.feature-card:hover {
  border-color: var(--border-hover);
}

.feature-icon-circle {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
}

.feature-card-title {
  font-size: 18px;
  font-weight: 500;
  letter-spacing: -0.02em;
}

.feature-card-desc {
  font-size: 14px;
  line-height: 1.6;
  color: var(--color-on-surface-muted);
}

/* Modal Popup */
.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background-color: rgba(24, 24, 22, 0.6);
  backdrop-filter: blur(8px);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-overlay.active {
  display: flex;
}

.modal-card {
  background-color: var(--color-surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  max-width: 500px;
  width: 100%;
  padding: 36px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.15);
  position: relative;
}

.modal-close-btn {
  position: absolute;
  top: 20px;
  right: 20px;
  font-size: 24px;
  color: var(--color-on-surface-subtle);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 20px;
}

.form-group label {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-on-surface);
}

.form-input {
  height: 44px;
  padding: 0 14px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background-color: var(--color-surface);
  font-family: var(--font-sans);
  font-size: 14px;
  outline: none;
}

.form-input:focus {
  border-color: var(--color-accent);
}

/* Footer */
.footer {
  border-top: 1px solid var(--border-subtle);
  padding: 80px 24px 60px 24px;
  background-color: var(--color-surface-alt);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 40px;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-on-surface-subtle);
  margin-bottom: 8px;
}

.footer-col a {
  font-size: 14px;
  color: var(--color-on-surface-muted);
}

.footer-col a:hover {
  color: var(--color-on-surface);
}

/* Mobile Breakpoints */
@media screen and (max-width: 991px) {
  .hero-title { font-size: 52px; }
  .workflow-grid { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
}

@media screen and (max-width: 640px) {
  .hero-title { font-size: 36px; }
  .hero-subtitle { font-size: 16px; }
  .feature-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
}