:root {
  --color-background: #ffffff;
  --color-surface: #f5f7fb;
  --color-accent: #0b5fff;
  --color-text: #111827;
  --color-muted: #4b5563;
  --color-border: #e5e7eb;
  --color-alt: #f9fafc;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --transition: all 0.3s ease;
  --shadow-card: 0 20px 45px rgba(15, 23, 42, 0.12);
  --shadow-light: 0 1px 2px rgba(15, 23, 42, 0.1), 0 8px 20px rgba(15, 23, 42, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-family);
  background: var(--color-background);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover,
a:focus {
  text-decoration: underline;
}

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

.container {
  width: min(1080px, 92vw);
  margin: 0 auto;
}

.eyebrow {
  letter-spacing: 0.2em;
  text-transform: uppercase;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: 1rem;
}

.lead {
  font-size: 1.125rem;
  color: var(--color-muted);
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.8rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: var(--transition);
}

.btn.primary {
  background: var(--color-accent);
  color: #fff;
}

.btn.primary:hover,
.btn.primary:focus {
  filter: brightness(0.9);
}

.btn.ghost {
  background: transparent;
  border-color: var(--color-border);
  color: var(--color-text);
}

.btn.ghost:hover,
.btn.ghost:focus {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.section {
  padding: 5rem 0;
}

.section.alternate {
  background: var(--color-alt);
}

.section-header {
  max-width: 640px;
  margin-bottom: 2.5rem;
}

.section-header h2 {
  margin: 0 0 0.75rem;
  font-size: 2rem;
}

.section-header p {
  margin: 0;
  color: var(--color-muted);
}

.site-header {
  position: sticky;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  z-index: 10;
  transition: var(--transition);
  border-bottom: 1px solid transparent;
}

.site-header.is-scrolled {
  border-bottom-color: rgba(229, 231, 235, 0.9);
  box-shadow: var(--shadow-light);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
  gap: 1rem;
}

.brand {
  font-weight: 700;
  font-size: 1.1rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.95rem;
  font-weight: 500;
}

.site-nav a {
  position: relative;
  padding-bottom: 0.25rem;
}

.site-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -0.3rem;
  width: 100%;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: var(--transition);
}

.site-nav a:focus::after,
.site-nav a:hover::after {
  transform: scaleX(1);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.menu-toggle span {
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: var(--transition);
}

.hero {
  padding-top: 7rem;
  background: linear-gradient(135deg, #f7faff 0%, #eef3ff 45%, #ffffff 100%);
}

.hero-inner {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: center;
  gap: 4rem;
}

.hero-copy h1 {
  font-size: clamp(2.2rem, 4vw, 3.2rem);
  line-height: 1.1;
  margin-bottom: 1.25rem;
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  padding: 0;
  margin: 0 0 1.8rem;
  list-style: none;
}

.hero-facts li {
  padding: 1rem;
  background: rgba(11, 95, 255, 0.08);
  border-radius: 16px;
  text-align: center;
  font-size: 0.9rem;
}

.hero-facts strong {
  display: block;
  font-size: 1.4rem;
  color: var(--color-accent);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.contact-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--color-muted);
}

.hero-portrait {
  position: relative;
  border-radius: 28px;
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.hero-portrait::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(11, 95, 255, 0.2) 0%, rgba(11, 95, 255, 0) 60%);
}

.hero-portrait img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.card {
  background: #fff;
  border-radius: 20px;
  padding: 1.75rem;
  box-shadow: var(--shadow-light);
  border: 1px solid rgba(226, 232, 240, 0.6);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 0.8rem;
  font-size: 1.15rem;
}

.card p {
  margin: 0;
  color: var(--color-muted);
}

.timeline {
  display: grid;
  gap: 2rem;
}

.timeline-item {
  padding: 1.5rem;
  border-radius: 18px;
  background: #fff;
  border: 1px solid rgba(209, 213, 219, 0.4);
  box-shadow: var(--shadow-light);
}

.timeline-meta h3 {
  margin: 0;
}

.timeline-meta span {
  display: block;
  color: var(--color-muted);
  margin-top: 0.3rem;
  font-size: 0.9rem;
}

.timeline-item ul {
  margin: 1rem 0 0;
  padding-left: 1.2rem;
  color: var(--color-muted);
}

.focus-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.focus-grid article {
  padding: 1.75rem;
  border-radius: 20px;
  border: 1px solid rgba(209, 213, 219, 0.5);
  background: linear-gradient(135deg, rgba(11, 95, 255, 0.08), rgba(11, 95, 255, 0));
}

.focus-grid h3 {
  margin-top: 0;
}

.expertise-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2.5rem;
  align-items: start;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  padding: 0;
  margin: 1.2rem 0 0;
  list-style: none;
}

.tag-list li {
  background: #fff;
  border-radius: 999px;
  padding: 0.5rem 1.2rem;
  border: 1px solid rgba(209, 213, 219, 0.6);
  font-size: 0.9rem;
}

.education {
  margin-top: 1rem;
  color: var(--color-muted);
  font-size: 0.95rem;
}

.chatbot-card {
  background: #fff;
  border-radius: 24px;
  padding: 2rem;
  box-shadow: var(--shadow-card);
  border: 1px solid rgba(209, 213, 219, 0.5);
}

.chatbot-card gradio-app {
  display: block;
  width: 100%;
  min-height: 550px;
  border-radius: 18px;
  overflow: hidden;
}

.contact {
  text-align: center;
}

.contact-inner {
  display: grid;
  gap: 2rem;
  justify-items: center;
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 1.5rem 0;
  background: #fff;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
}

@media (max-width: 960px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-facts {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-portrait {
    max-width: 360px;
    margin: 0 auto;
  }
}

@media (max-width: 760px) {
  .site-nav {
    position: absolute;
    top: 100%;
    right: 1rem;
    background: #fff;
    border-radius: 16px;
    padding: 1rem 1.5rem;
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
    box-shadow: var(--shadow-card);
    transform: translateY(-10px);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
  }

  .site-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
  }

  .menu-toggle {
    display: flex;
  }

  .footer-inner {
    flex-direction: column;
    gap: 0.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}