:root {
  --primary: #00d9ff;
  --primary-dim: #00a8cc;
  --accent: #ffd700;
  --bg-dark: #0a0e27;
  --bg-darker: #050810;
  --surface: #151b2f;
  --surface-light: #1e2639;
  --text-primary: #ffffff;
  --text-secondary: #b0b8c8;
  --border: #2a3347;
}

* {
  box-sizing: border-box;
}

html {
  max-width: 100%;
  overflow-x: hidden;
}

body {
  margin: 0;
  min-height: 100dvh;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text-primary);
  background: var(--bg-dark);
  line-height: 1.6;
  max-width: 100%;
  overflow-x: hidden;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--primary-dim);
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--border);
  background: rgba(10, 14, 39, 0.95);
  backdrop-filter: blur(12px);
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px clamp(20px, 5vw, 40px);
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 1.1rem;
}

.logo img {
  width: 40px;
  height: 40px;
  object-fit: contain;
}

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

.nav a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.nav a:hover {
  color: var(--primary);
}

.nav a.cta {
  background: var(--primary);
  color: var(--bg-dark);
  padding: 8px 16px;
  border-radius: 6px;
  font-weight: 600;
}

.nav a.cta:hover {
  background: var(--primary-dim);
  color: var(--bg-dark);
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  color: var(--primary);
  font-size: 1.35rem;
  font-weight: 800;
  cursor: pointer;
}

.menu-toggle:hover,
.menu-toggle:focus-visible {
  border-color: var(--primary);
  outline: none;
}

/* Main content */
main {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  overflow-x: hidden;
}

/* Hero Section */
.hero {
  padding: clamp(60px, 10vw, 100px) clamp(20px, 5vw, 40px);
  text-align: center;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.hero h1 {
  font-size: clamp(2.5rem, 7vw, 4rem);
  line-height: 1.2;
  margin: 0 0 20px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.3rem;
  color: var(--text-secondary);
  margin: 0 0 20px;
  font-weight: 600;
}

.hero-description {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin: 0 0 40px;
  line-height: 1.8;
}

.beta-note {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 24px;
}

/* Buttons */
.button {
  display: inline-block;
  padding: 14px 32px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 1rem;
  text-align: center;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
  text-decoration: none;
}

.button-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  color: var(--bg-dark);
}

.button-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(0, 217, 255, 0.3);
}

.button:disabled {
  cursor: wait;
  opacity: 0.65;
  transform: none;
}

.button-large {
  padding: 16px 48px;
  font-size: 1.1rem;
}

/* Simulation Promo */
.simulation-promo {
  padding: 56px clamp(20px, 5vw, 40px);
  border-top: 1px solid var(--border);
  background: rgba(0, 217, 255, 0.03);
}

.simulation-promo-content {
  max-width: 780px;
  margin: 0 auto;
  text-align: center;
}

.simulation-promo h2 {
  margin: 0 0 14px;
  font-size: clamp(1.8rem, 4vw, 2.4rem);
}

.simulation-promo p {
  margin: 0 0 26px;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* Features Section */
.features {
  padding: 80px clamp(20px, 5vw, 40px);
  border-top: 1px solid var(--border);
}

.features h2 {
  font-size: clamp(2rem, 5vw, 2.8rem);
  text-align: center;
  margin: 0 0 60px;
  font-weight: 800;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px 24px;
  transition: all 0.3s ease;
}

.feature-card:hover {
  border-color: var(--primary);
  background: var(--surface-light);
  transform: translateY(-4px);
}

.feature-icon {
  width: 68px;
  height: 68px;
  display: grid;
  place-items: center;
  margin-bottom: 16px;
}

.feature-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.feature-card h3 {
  margin: 0 0 12px;
  font-size: 1.2rem;
  color: var(--primary);
}

.feature-card p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* How It Works */
.how-it-works {
  padding: 80px clamp(20px, 5vw, 40px);
  background: rgba(0, 217, 255, 0.03);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.how-it-works h2 {
  font-size: clamp(2rem, 5vw, 2.8rem);
  text-align: center;
  margin: 0 0 60px;
  font-weight: 800;
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px 24px;
  position: relative;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  color: var(--bg-dark);
  border-radius: 50%;
  font-weight: 800;
  font-size: 1.3rem;
  margin-bottom: 20px;
}

.step h3 {
  margin: 0 0 12px;
  font-size: 1.1rem;
  color: var(--primary);
}

.step p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Simulation */
.simulation {
  padding: 80px clamp(20px, 5vw, 40px);
  border-top: 1px solid var(--border);
  background: rgba(0, 217, 255, 0.03);
  min-width: 0;
  overflow-x: hidden;
}

.section-heading {
  max-width: 780px;
  margin: 0 auto 36px;
  text-align: center;
}

.section-heading h2 {
  margin: 0 0 14px;
  font-size: clamp(2rem, 5vw, 2.8rem);
  font-weight: 800;
}

.section-heading p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.simulation-form {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr)) auto;
  gap: 14px;
  align-items: end;
  margin: 0 0 24px;
  padding: 22px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  min-width: 0;
  max-width: 100%;
}

.simulation-form label {
  display: grid;
  gap: 8px;
  min-width: 0;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 700;
}

.simulation-form input,
.simulation-form select {
  width: 100%;
  max-width: 100%;
  min-width: 0;
  min-height: 46px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-darker);
  color: var(--text-primary);
  padding: 10px 12px;
  font: inherit;
}

.simulation-form select {
  cursor: pointer;
}

.simulation-form input[type="date"] {
  appearance: none;
  -webkit-appearance: none;
}

.simulation-form input:focus,
.simulation-form select:focus {
  border-color: var(--primary);
  outline: none;
}

.field-with-help {
  position: relative;
}

.field-label-row {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.help-trigger {
  display: inline;
  width: auto;
  height: auto;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--primary);
  font: inherit;
  font-size: 0.95rem;
  font-weight: 800;
  line-height: 1;
  cursor: help;
}

.help-trigger:hover,
.help-trigger:focus-visible {
  color: var(--accent);
  outline: none;
}

.help-tooltip {
  position: absolute;
  left: 0;
  bottom: calc(100% + 8px);
  z-index: 20;
  display: none;
  width: min(320px, 80vw);
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-darker);
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 600;
  line-height: 1.45;
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.35);
}

.field-with-help:hover .help-tooltip,
.field-with-help:focus-within .help-tooltip {
  display: block;
}

.simulation-status,
.simulation-error {
  margin: 0 0 20px;
  padding: 14px 16px;
  border-radius: 8px;
  font-weight: 700;
}

.simulation-status {
  border: 1px solid rgba(0, 217, 255, 0.32);
  background: rgba(0, 217, 255, 0.1);
  color: var(--primary);
}

.simulation-error {
  border: 1px solid rgba(255, 92, 92, 0.36);
  background: rgba(255, 92, 92, 0.12);
  color: #ff9f9f;
}

.simulation-summary {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
  margin: 0 0 24px;
  min-width: 0;
}

.simulation-summary div {
  min-width: 0;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
}

.simulation-summary span,
.simulation-summary strong {
  display: block;
}

.simulation-summary span {
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 700;
}

.simulation-summary strong {
  margin-top: 5px;
  color: var(--text-primary);
  font-size: 1rem;
  overflow-wrap: anywhere;
}

.simulation-results[hidden] {
  display: none;
}

.simulation-results {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  min-width: 0;
}

.simulation-outcome {
  margin: 0;
  padding: 18px 20px;
  border: 1px solid rgba(255, 215, 0, 0.38);
  border-left: 4px solid var(--accent);
  border-radius: 8px;
  background: rgba(255, 215, 0, 0.08);
  color: var(--text-primary);
  font-size: 1.08rem;
  font-weight: 800;
  line-height: 1.55;
  max-width: 100%;
  overflow-wrap: anywhere;
}

.simulation-outcome[hidden] {
  display: none;
}

.simulation-result-section h3 {
  margin: 0 0 14px;
  color: var(--primary);
  font-size: 1.25rem;
  line-height: 1.3;
}

.metric-select-label {
  display: inline-grid;
  gap: 8px;
  margin: 0 0 16px;
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 700;
}

.metric-select-label select {
  min-width: 260px;
  min-height: 44px;
  padding: 9px 42px 9px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-darker);
  color: var(--text-primary);
  font: inherit;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
}

.metric-select-label select:hover,
.metric-select-label select:focus {
  border-color: var(--primary);
  outline: none;
}

.metric-select-label option {
  background: var(--bg-darker);
  color: var(--text-primary);
}

.simulation-chart {
  min-width: 0;
  max-width: 100%;
  min-height: 420px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  overflow: hidden;
}

.simulation-chart .js-plotly-plot,
.simulation-chart .plot-container,
.simulation-chart .svg-container {
  max-width: 100%;
}

/* For Whom Section */
.for-whom {
  padding: 80px clamp(20px, 5vw, 40px);
  background: rgba(255, 215, 0, 0.02);
  border-top: 1px solid var(--border);
}

.for-whom h2 {
  font-size: clamp(2rem, 5vw, 2.8rem);
  margin: 0 0 40px;
  font-weight: 800;
  text-align: center;
}

.audience {
  max-width: 800px;
  margin: 0 auto;
}

.audience p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin: 0 0 24px;
}

.audience ul {
  list-style: none;
  padding: 0;
  margin: 0 0 32px;
}

.audience li {
  padding: 12px 0;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  position: relative;
  padding-left: 28px;
}

.audience li:before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 800;
}

.note {
  background: rgba(0, 217, 255, 0.1);
  border-left: 3px solid var(--primary);
  padding: 16px 20px;
  border-radius: 6px;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.note strong {
  color: var(--primary);
}

/* Download Section */
.download {
  padding: 80px clamp(20px, 5vw, 40px);
  text-align: center;
  border-top: 1px solid var(--border);
}

.download h2 {
  font-size: clamp(2rem, 5vw, 2.8rem);
  margin: 0 0 20px;
  font-weight: 800;
}

.download > p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin: 0 0 40px;
}

.requirements {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 24px;
}

/* Footer */
.footer {
  border-top: 1px solid var(--border);
  padding: 32px clamp(20px, 5vw, 40px);
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
  background: rgba(0, 0, 0, 0.2);
}

.footer a {
  color: var(--primary);
}

/* Responsive */
@media (max-width: 768px) {
  .header-content {
    position: relative;
  }

  .menu-toggle {
    display: grid;
  }

  .nav {
    display: none;
    position: absolute;
    top: calc(100% + 10px);
    left: clamp(20px, 5vw, 40px);
    right: clamp(20px, 5vw, 40px);
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: rgba(10, 14, 39, 0.98);
    box-shadow: 0 18px 40px rgba(0, 0, 0, 0.35);
  }

  .nav.show {
    display: flex;
  }

  .nav a,
  .nav a.cta {
    display: block;
    width: 100%;
    padding: 11px 12px;
    border-radius: 6px;
    font-size: 0.95rem;
  }

  .nav a:hover {
    background: rgba(0, 217, 255, 0.08);
  }

  .hero {
    padding: 40px clamp(20px, 5vw, 40px);
  }

  .hero h1 {
    font-size: 2rem;
  }

  .features,
  .how-it-works,
  .simulation,
  .simulation-promo,
  .for-whom,
  .download {
    padding: 60px 16px;
  }

  .features h2,
  .how-it-works h2,
  .section-heading h2,
  .for-whom h2,
  .download h2 {
    font-size: 1.8rem;
    margin-bottom: 40px;
  }

  .features-grid,
  .steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .simulation-form {
    grid-template-columns: 1fr;
    padding: 16px;
  }

  .simulation-summary {
    grid-template-columns: minmax(0, 1fr);
  }

  .simulation-outcome {
    padding: 16px;
    font-size: 1rem;
  }

  .metric-select-label,
  .metric-select-label select,
  .help-tooltip {
    width: 100%;
    min-width: 0;
  }

  .simulation-chart {
    min-height: 360px;
  }
}

@media (max-width: 640px) {
  .hero-subtitle {
    font-size: 1.1rem;
  }

  .button {
    padding: 12px 24px;
    font-size: 0.9rem;
  }

  .button-large {
    padding: 14px 32px;
    font-size: 1rem;
  }
}