/* ==========================================================================
   vinTsys Corporate Website CSS
   ========================================================================== */

/* 1. Design System Tokens (CSS Custom Properties) */
:root {
  --color-brand: #C49A3C;
  --color-brand-dark: #9A7A2A;
  --color-brand-light: #E8DCC4;
  --color-bg: #FAFAF7;
  --color-surface: #F2F0EA;
  --color-border: #E0D9CC;
  --color-text-primary: #1C1A17;
  --color-text-secondary: #6B6558;
  --color-white: #FFFFFF;
  --color-dark-footer: #1C1A17;
  --color-footer-text: #A09880;

  /* Typography */
  --font-sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: 'JetBrains Mono', Courier, monospace;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 3rem;
  --spacing-xl: 5rem;

  /* Border Radius & Transitions */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  --shadow-sm: 0 2px 4px rgba(28, 26, 23, 0.04);
  --shadow-md: 0 4px 12px rgba(28, 26, 23, 0.08);
  --shadow-lg: 0 8px 24px rgba(28, 26, 23, 0.12);
}

/* 2. Reset & Base Styles */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-text-primary);
}

p {
  margin-bottom: 1.25rem;
}

a {
  color: var(--color-brand);
  text-decoration: none;
  transition: color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
}

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

ul {
  list-style: none;
}

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

/* Base Accessibility / Focus Styles */
*:focus-visible {
  outline: 3px solid var(--color-brand);
  outline-offset: 3px;
}

/* Layout Container */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section-badge {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--color-brand);
  margin-bottom: var(--spacing-sm);
  display: inline-block;
}

.section-badge.badge-inverted {
  color: var(--color-white);
  border-bottom: 2px solid var(--color-white);
  padding-bottom: 2px;
}

.section-heading {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-md);
}

.section-body {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 720px;
}

/* 3. Navigation Header */
.header-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: rgba(250, 250, 247, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.header-nav.scrolled {
  background-color: rgba(250, 250, 247, 0.95);
  border-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: var(--spacing-sm) var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo-link {
  display: flex;
  align-items: center;
  z-index: 1010;
}

.nav-logo-img {
  height: 36px;
  width: auto;
}

.nav-mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1010;
  padding: 0.5rem;
}

.hamburger-line {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-text-primary);
  margin: 4px 0;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.nav-list {
  display: flex;
  gap: var(--spacing-md);
}

.nav-link {
  color: var(--color-text-secondary);
  font-weight: 500;
  font-size: 0.9375rem;
  padding: 0.5rem 0;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-brand);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition-fast);
}

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

.nav-link:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-cta-btn {
  background-color: var(--color-brand);
  color: var(--color-white);
  padding: 0.625rem 1.25rem;
  font-size: 0.975rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
  display: inline-block;
}

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

/* 4. Hero Section */
.section-hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl) 0 var(--spacing-lg);
  background-color: var(--color-bg);
  position: relative;
  overflow: hidden;
}

.section-hero::before {
  content: '';
  position: absolute;
  top: -20%;
  right: -20%;
  width: 50%;
  height: 60%;
  background: radial-gradient(circle, rgba(196, 154, 60, 0.05) 0%, rgba(250, 250, 247, 0) 70%);
  z-index: 1;
  pointer-events: none;
}

.hero-container {
  max-width: 1000px;
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  gap: var(--spacing-xl);
  z-index: 2;
}

.hero-logo-col {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-text-col {
  flex: 1 1 auto;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
}

.hero-logo-mark-img {
  height: 300px;
  width: auto;
}

.hero-headline {
  font-size: 3.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: var(--spacing-md);
  color: var(--color-text-primary);
}

.hero-subline {
  font-size: 1.25rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 0 var(--spacing-lg);
}

.hero-preview {
  max-width: 600px;
  margin: 0 0 var(--spacing-lg);
}

.hero-preview-lead {
  font-size: 1.1rem;
  font-weight: 600;
  line-height: 1.6;
  color: var(--color-text-primary);
  margin: 0 0 0.5rem;
}

.hero-preview-item {
  font-size: 1.1rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
  margin: 0 0 0.35rem;
}

.hero-preview-item strong {
  color: var(--color-brand-dark);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
  width: 100%;
  max-width: 600px;
}

.hero-btn-primary {
  background-color: var(--color-brand);
  color: var(--color-white);
  padding: 1rem 2rem;
  font-size: 1.0625rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  transition: background-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.hero-btn-primary:hover {
  background-color: var(--color-brand-dark);
  color: var(--color-white);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.hero-link-secondary {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color var(--transition-fast), transform var(--transition-fast);
}

.hero-link-secondary:hover {
  color: var(--color-brand-dark);
  transform: translateY(2px);
}

/* 5. ScholarInt Section */
.section-scholarint {
  padding: var(--spacing-xl) 0;
  border-top: 1px solid var(--color-border);
  background-color: var(--color-bg);
}

.scholarint-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  align-items: start;
}

.scholarint-signals {
  background-color: var(--color-surface);
  padding: var(--spacing-md);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
}

.signal-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.signal-item {
  display: flex;
  gap: var(--spacing-sm);
  align-items: flex-start;
}

.signal-icon {
  color: var(--color-brand);
  flex-shrink: 0;
  margin-top: 0.125rem;
}

.signal-text {
  font-size: 0.9375rem;
  color: var(--color-text-primary);
  font-weight: 500;
  line-height: 1.5;
}

.scholarint-status-callout {
  background-color: var(--color-surface);
  border-left: 4px solid var(--color-brand);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-bottom: var(--spacing-lg);
  max-width: 720px;
}

.status-note {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  margin-bottom: 0;
  font-style: italic;
}

.scholarint-action {
  margin-top: var(--spacing-md);
}

.scholarint-btn {
  background-color: var(--color-brand);
  color: var(--color-white);
  padding: 0.875rem 1.75rem;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  display: inline-block;
}

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

/* 6. Learn Section */
.section-learn {
  padding: var(--spacing-xl) 0;
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
}

.learn-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--spacing-lg);
  align-items: start;
}

.learn-journal-link {
  font-weight: 600;
  font-size: 1.0625rem;
  display: inline-block;
  margin-top: var(--spacing-sm);
  border-bottom: 2px solid transparent;
}

.learn-journal-link:hover {
  border-bottom-color: var(--color-brand-dark);
}

.learn-cards {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.article-card {
  background-color: var(--color-bg);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.article-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.article-title {
  font-size: 1.1875rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.article-desc {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  line-height: 1.5;
}

/* 7. BioNT Recognition Section */
.section-biont {
  padding: var(--spacing-xl) 0;
  background-color: var(--color-bg);
  border-top: 1px solid var(--color-border);
}

.biont-citation-block {
  border-left: 4px solid var(--color-brand);
  padding-left: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
  max-width: 800px;
}

.citation-paragraph {
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--color-text-primary);
  margin-bottom: 1rem;
}

.citation-paragraph:last-child {
  margin-bottom: 0;
}

.clarifying-note {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  max-width: 720px;
  line-height: 1.6;
}

/* 8. Our Work Section */
.section-our-work {
  padding: var(--spacing-xl) 0;
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
}

.our-work-intro {
  font-size: 1.0625rem;
  color: var(--color-text-secondary);
  max-width: 720px;
  margin-bottom: var(--spacing-lg);
}

.demo-card {
  background-color: var(--color-bg);
  padding: var(--spacing-lg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  max-width: 800px;
}

.demo-badge {
  font-family: var(--font-sans);
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  padding: 0.25rem 0.625rem;
  border-radius: 50px;
  display: inline-block;
  margin-bottom: var(--spacing-sm);
}

.demo-title {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
}

.demo-body-content {
  margin-bottom: var(--spacing-md);
}

.demo-body-paragraph {
  font-size: 0.9625rem;
  color: var(--color-text-secondary);
  line-height: 1.65;
}

.demo-body-paragraph:last-child {
  margin-bottom: 0;
}

.demo-status-tag {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-brand-dark);
  display: inline-block;
}

/* 9. About Section */
.section-about {
  padding: var(--spacing-xl) 0;
  background-color: var(--color-bg);
  border-top: 1px solid var(--color-border);
}

.about-subsection {
  margin-top: var(--spacing-md);
}

.about-subsection-founder {
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-md);
}

.about-grid .section-body {
  max-width: 100%;
  font-size: 1.125rem;
}

/* 10. Contact / CTA Section */
.section-contact {
  padding: var(--spacing-xl) 0;
  background-color: var(--color-brand);
  color: var(--color-white);
  border-top: 1px solid var(--color-brand-dark);
  text-align: center;
}

.contact-container {
  max-width: 800px;
}

.contact-heading {
  color: var(--color-white);
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-md);
}

.contact-body {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.125rem;
  line-height: 1.6;
  max-width: 650px;
  margin: 0 auto var(--spacing-lg);
}

.contact-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
}

.contact-cta-btn {
  background-color: var(--color-white);
  color: var(--color-brand);
  padding: 1rem 2rem;
  font-size: 1.0625rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  transition: background-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
}

.contact-cta-btn:hover {
  background-color: var(--color-brand-dark);
  color: var(--color-white);
  transform: translateY(-2px);
}

.contact-direct {
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.8);
}

.contact-email {
  color: var(--color-white);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.contact-email:hover {
  color: rgba(255, 255, 255, 0.9);
}

/* 11. Footer Section */
.footer {
  background-color: var(--color-dark-footer);
  color: var(--color-footer-text);
  padding: var(--spacing-lg) 0;
  font-size: 0.875rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-container {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: var(--spacing-lg);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.footer-logo-mark {
  height: 36px;
  width: auto;
}

.footer-brand-text {
  display: flex;
  flex-direction: column;
}

.footer-company {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-white);
}

.footer-tagline {
  font-size: 0.75rem;
  color: var(--color-footer-text);
}

.footer-info {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  align-items: flex-end;
  text-align: right;
}

.footer-location {
  font-weight: 500;
  color: var(--color-white);
}

.footer-links {
  margin-bottom: 0;
}

.footer-link {
  color: var(--color-footer-text);
}

.footer-link:hover {
  color: var(--color-white);
}

.footer-email-link {
  color: var(--color-white);
  font-weight: 500;
}

.footer-email-link:hover {
  color: var(--color-brand);
}

.footer-copyright {
  margin-top: 0.5rem;
  font-size: 0.8125rem;
  opacity: 0.6;
}

/* ==========================================================================
   12. Responsive Styles (Breakpoints)
   ========================================================================== */

/* Mobile view adaptations (< 768px) */
@media (max-width: 767.98px) {
  .section-heading {
    font-size: 1.75rem;
  }

  .hero-headline {
    font-size: 2.5rem;
  }

  .hero-subline {
    font-size: 1.125rem;
  }

  /* Sticky Navigation Collapse Mobile */
  .nav-mobile-toggle {
    display: block;
  }

  .nav-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-bg);
    flex-direction: column;
    padding: var(--spacing-md);
    gap: var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition-normal), opacity var(--transition-normal);
    z-index: 990;
  }

  .header-nav.nav-open .nav-menu {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .header-nav.nav-open .hamburger-line:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }

  .header-nav.nav-open .hamburger-line:nth-child(2) {
    opacity: 0;
  }

  .header-nav.nav-open .hamburger-line:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }

  .nav-list {
    flex-direction: column;
    align-items: center;
    width: 100%;
    gap: var(--spacing-xs);
  }

  .nav-link {
    font-size: 1.0625rem;
    padding: 0.75rem 0;
  }

  .nav-cta-wrapper {
    width: 100%;
    text-align: center;
  }

  .nav-cta-btn {
    width: 80%;
  }

  /* Grid Stackings */
  .scholarint-grid,
  .learn-grid,
  .about-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }

  .footer-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: var(--spacing-md);
  }

  .footer-info {
    align-items: center;
    text-align: center;
  }

  /* Hero: Revert to stacked layout on mobile */
  .hero-container {
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-lg);
  }

  .hero-text-col {
    text-align: center;
  }

  .hero-actions {
    align-items: center;
  }

  .hero-subline {
    margin: 0 auto var(--spacing-lg);
  }

  .hero-logo-mark-img {
    height: 160px;
  }
}

/* Tablet view adaptations (640px to 1024px) */
@media (min-width: 640px) and (max-width: 1024px) {
  .hero-headline {
    font-size: 3rem;
  }
  
  .scholarint-grid,
  .learn-grid {
    gap: var(--spacing-md);
  }
}

/* Large screen spacing refinements */
@media (min-width: 1200px) {
  .container {
    padding: 0;
  }
}

/* ==========================================================================
   13. Print Guidelines
   ========================================================================== */
@media print {
  body {
    background-color: var(--color-white);
    color: #000000;
  }

  .header-nav,
  .hero-actions,
  .scholarint-action,
  .contact-actions {
    display: none !important;
  }

  .section-hero {
    min-height: auto;
    padding: var(--spacing-md) 0;
  }

  .container {
    max-width: 100%;
  }

  a[href^="http"]::after {
    content: " (" attr(href) ")";
  }
}