/* ==========================================================================
   gviolato.com — Main stylesheet
   ========================================================================== */

/* --------------------------------------------------------------------------
   Custom properties
   -------------------------------------------------------------------------- */
:root {
  --ink: #0f172a;
  --text: #1e293b;
  --muted: #64748b;
  --accent: #1d4ed8;
  --accent-dark: #1e40af;
  --border: #e2e8f0;
  --bg: #ffffff;
  --bg-alt: #f8fafc;

  --max-w: 860px;
  --nav-h: 60px;

  --radius: 6px;
  --radius-lg: 12px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.10);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 16px);
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--accent-dark);
}

ul {
  list-style: none;
}

/* --------------------------------------------------------------------------
   Typography helpers
   -------------------------------------------------------------------------- */
.section-label {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

h2.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 0.5rem;
  line-height: 1.25;
}

h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--ink);
  line-height: 1.3;
}

.section-intro {
  color: var(--muted);
  max-width: 560px;
  margin-bottom: 2.5rem;
}

/* --------------------------------------------------------------------------
   Layout helpers
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

section {
  padding-block: 5rem;
}

section:nth-child(even) {
  background: var(--bg-alt);
}

/* --------------------------------------------------------------------------
   Navigation
   -------------------------------------------------------------------------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.nav-brand {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--ink);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.nav-brand:hover {
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 0.25rem;
  align-items: center;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--muted);
  padding: 0.35rem 0.6rem;
  border-radius: var(--radius);
  transition: color 0.15s, background 0.15s;
}

.nav-links a:hover {
  color: var(--ink);
  background: var(--bg-alt);
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
  border: none;
  background: none;
  border-radius: var(--radius);
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */
.hero {
  padding-block: 5rem 4rem;
  background: var(--bg);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 3rem;
  align-items: center;
}

.hero-text h1 {
  font-size: clamp(2rem, 5vw, 2.75rem);
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 0.5rem;
}

.hero-subtitle {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 1.25rem;
}

.hero-tagline {
  font-size: 1rem;
  color: var(--muted);
  max-width: 480px;
  margin-bottom: 2rem;
  line-height: 1.65;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.6rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
  text-decoration: none;
}

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

.btn-primary:hover {
  background: var(--accent-dark);
  color: #fff;
  box-shadow: 0 2px 8px rgba(29, 78, 216, 0.3);
}

.btn-secondary {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--border);
}

.btn-secondary:hover {
  background: var(--bg-alt);
  border-color: #cbd5e1;
  color: var(--ink);
}

/* Profile photo */
.hero-photo {
  flex-shrink: 0;
}

.photo-circle {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  overflow: hidden;
  border: 3px solid var(--border);
  box-shadow: var(--shadow-md);
  background: var(--bg-alt);
  position: relative;
}

.photo-circle img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Fallback initials circle */
.photo-initials {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: linear-gradient(135deg, #1e3a5f 0%, var(--accent) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 3px solid var(--border);
  box-shadow: var(--shadow-md);
}

.photo-initials span {
  font-size: 2.25rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.03em;
}

/* --------------------------------------------------------------------------
   About
   -------------------------------------------------------------------------- */
.about-body p {
  color: var(--text);
  margin-bottom: 1.25rem;
  max-width: 680px;
}

.about-body p:last-child {
  margin-bottom: 0;
}

.about-meta {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.about-meta-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--muted);
}

.about-meta-item svg {
  flex-shrink: 0;
  color: var(--accent);
}

/* --------------------------------------------------------------------------
   Services
   -------------------------------------------------------------------------- */
.services-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.service-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.service-card:hover {
  box-shadow: var(--shadow-md);
  border-color: #cbd5e1;
}

.service-card h3 {
  margin-bottom: 0.6rem;
  color: var(--ink);
}

.service-desc {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 1rem;
  line-height: 1.6;
}

.service-bullets {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.service-bullets li {
  font-size: 0.85rem;
  color: var(--text);
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.service-bullets li::before {
  content: '';
  display: block;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
  margin-top: 0.55em;
}

/* --------------------------------------------------------------------------
   Experience timeline
   -------------------------------------------------------------------------- */
.timeline {
  position: relative;
  padding-left: 1.5rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.5rem;
  bottom: 0.5rem;
  width: 2px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  padding-bottom: 2.5rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -1.5rem;
  top: 0.45rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-alt);
  box-shadow: 0 0 0 2px var(--accent);
  transform: translateX(-4px);
}

.timeline-period {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.03em;
  margin-bottom: 0.2rem;
}

.timeline-role {
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.3;
}

.timeline-company {
  font-size: 0.875rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.timeline-company .sep {
  margin-inline: 0.3rem;
}

.timeline-desc {
  font-size: 0.9rem;
  color: var(--text);
  line-height: 1.65;
  max-width: 640px;
}

/* --------------------------------------------------------------------------
   Research
   -------------------------------------------------------------------------- */
.research-subsection {
  margin-bottom: 3rem;
}

.research-subsection:last-child {
  margin-bottom: 0;
}

.research-subsection h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
  text-transform: uppercase;
  letter-spacing: 0.07em;
  font-size: 0.8rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.patent-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.patent-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.5rem 1rem;
  align-items: start;
  transition: box-shadow 0.15s ease;
}

.patent-item:hover {
  box-shadow: var(--shadow-sm);
}

.patent-title {
  font-weight: 600;
  color: var(--ink);
  font-size: 0.925rem;
}

.patent-numbers {
  font-size: 0.78rem;
  color: var(--accent);
  font-weight: 600;
  white-space: nowrap;
  text-align: right;
}

.patent-desc {
  font-size: 0.875rem;
  color: var(--muted);
  grid-column: 1 / -1;
  line-height: 1.55;
}

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.pub-item {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: 0 1rem;
  align-items: start;
}

.pub-year {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent);
  padding-top: 0.1rem;
}

.pub-body {}

.pub-text {
  font-size: 0.9rem;
  color: var(--text);
  line-height: 1.55;
}

.pub-role {
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: 0.2rem;
}

/* --------------------------------------------------------------------------
   Demos
   -------------------------------------------------------------------------- */
.demos-coming-soon {
  color: var(--muted);
  font-style: italic;
}

.demos-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.demo-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.demo-card:hover {
  box-shadow: var(--shadow-md);
  border-color: #cbd5e1;
}

.demo-card h3 {
  color: var(--ink);
}

.demo-desc {
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.6;
  flex: 1;
}

.demo-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 0.5rem;
}

.demo-tech {
  font-size: 0.75rem;
  color: var(--muted);
  font-family: 'SF Mono', 'Fira Code', monospace;
}

.demo-link {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.demo-link:hover {
  color: var(--accent-dark);
}

/* --------------------------------------------------------------------------
   Contact
   -------------------------------------------------------------------------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.6fr;
  gap: 4rem;
  align-items: start;
}

.contact-info p {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 1.5rem;
  line-height: 1.65;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text);
}

.contact-link svg {
  color: var(--accent);
  flex-shrink: 0;
}

/* Form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.form-group label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: 0.01em;
}

.form-group input,
.form-group textarea {
  padding: 0.6rem 0.85rem;
  font-size: 0.9rem;
  font-family: inherit;
  color: var(--text);
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  width: 100%;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(29, 78, 216, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.form-submit {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: flex-start;
}

.form-message {
  font-size: 0.875rem;
  padding: 0.6rem 1rem;
  border-radius: var(--radius);
  display: none;
}

.form-message.success {
  display: block;
  background: #f0fdf4;
  color: #166534;
  border: 1px solid #bbf7d0;
}

.form-message.error {
  display: block;
  background: #fef2f2;
  color: #991b1b;
  border: 1px solid #fecaca;
}

.btn-submit {
  width: 100%;
  justify-content: center;
  padding: 0.75rem;
}

.btn-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Turnstile wrapper */
.turnstile-wrapper {
  margin-top: 0.25rem;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
  padding-block: 2rem;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.footer-copy {
  font-size: 0.825rem;
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.footer-links a {
  font-size: 0.825rem;
  color: var(--muted);
  transition: color 0.15s;
}

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

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 700px) {
  section {
    padding-block: 3.5rem;
  }

  /* Nav */
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: stretch;
    padding: 0.75rem 1.5rem 1rem;
    gap: 0.15rem;
    box-shadow: var(--shadow-md);
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    padding: 0.55rem 0.5rem;
  }

  .nav-toggle {
    display: flex;
  }

  /* Hero */
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-photo {
    order: -1;
    display: flex;
    justify-content: center;
  }

  .photo-circle,
  .photo-initials {
    width: 120px;
    height: 120px;
  }

  .photo-initials span {
    font-size: 1.75rem;
  }

  .hero-tagline {
    margin-inline: auto;
  }

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

  /* Services */
  .services-grid {
    grid-template-columns: 1fr;
  }

  /* Timeline */
  .timeline {
    padding-left: 1.25rem;
  }

  /* Research */
  .patent-item {
    grid-template-columns: 1fr;
  }

  .patent-numbers {
    text-align: left;
  }

  .pub-item {
    grid-template-columns: 1fr;
  }

  .pub-year {
    margin-bottom: 0.2rem;
  }

  /* Demos */
  .demos-grid {
    grid-template-columns: 1fr;
  }

  /* Contact */
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  /* Footer */
  .footer-inner {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}

@media (max-width: 480px) {
  h2.section-title {
    font-size: 1.5rem;
  }
}