:root {
  --radius: 0.75rem;                /* Border radius for rounded corners */
  --space: 1rem;                    /* Base spacing unit */
  --color-background: #f9fdff;      /* Light gray background */
  --color-blue: #044cd4;            /* Main blue accent */
  --color-aqua-green: #00c8b9;      /* Aqua green accent */
  --color-yellow: #ffc700;          /* Yellow highlight */
  --color-orange-red: #ff6245;      /* Orange-red accent */
  --color-card: #ffffff;            /* Card background color */
  --color-text: black;            /* Main text color */
  --shadow: 0 30px 60px -10px rgba(4,77,212,0.15); /* Card shadow */
  --transition: 0.6s cubic-bezier(.22,.61,.36,1);  /* Default transition */
  --fs-base: 1.5rem;                  /* Base font size */
  --break-md: 768px;                /* Medium breakpoint for responsiveness */
  font-family: 'Inter', system-ui,-apple-system,BlinkMacSystemFont,sans-serif; /* Font stack */
}

/* =========================
   Box Sizing
   ========================= */
/* Use border-box for all elements for easier sizing */
*,
*::before,
*::after { box-sizing:border-box; }
/* ==========================
Logo
===========================*/
.logo {
  display: flex;
  align-items: center;
  /* optional: limit size so it stays compact in header */
  max-height: 100px;
}

.logo img {
  display: block;
  height: 5vh;        /* desired visual height */
  width: auto;         /* preserve aspect ratio */
  max-width: 100%;     /* responsive */
}


/* =========================
   Body Styles
   ========================= */
/* Set up background, text color, and base layout */
body {
  margin:0;
  color: var(--color-text);
  line-height:1.5;
  font-size: var(--fs-base);
  min-height:100vh;
  scroll-behavior: smooth;
}

html {
  scroll-behavior: smooth;
}

/* =========================
   Background Canvas
   ========================= */
/* Fixed canvas for network background, behind all content */
#network-bg {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0; /* Ensure it's behind other content */
  pointer-events: none;
  display: block;
}

/* Ensure main content is above the background canvas */
body > * {
  position: relative;
  z-index: 1;
}

.page-glow {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -2;
  background:
    radial-gradient(
      circle at 30% 40%, 
      transparent 70%, 
      color-mix(in srgb, white 40%, var(--color-aqua-green) 60%) 100%
    ),
    radial-gradient(
      circle at 70% 60%, 
      transparent 80%, 
      color-mix(in srgb, white 40%, var(--color-yellow) 60%) 100%
    );
  filter: blur(250px);
  will-change: transform;
}








/* =========================
   Header Styles
   ========================= */
/* Sticky header with blur and border */
.site-header {
  position:sticky;
  top:0;
  z-index:100;
  backdrop-filter: blur(14px);
  background: rgba(255,255,255,0.85);
  border-bottom:1px solid rgba(31,41,55,0.08);
}
.site-header .inner {
  max-width:1120px;
  margin:0 auto;
  padding:0.75rem 1rem;
  display:flex;
  align-items:center;
  gap:1rem;
  justify-content:space-between;
}
.logo {
  font-weight:700;
  font-size:1.25rem;
  letter-spacing:0.5px;
  color: var(--color-blue); /* Logo uses main blue */
}

/* =========================
   Navigation Styles
   ========================= */
/* Hide navigation by default (shown on desktop) */
.nav {
  display:none;
  gap:1.25rem;
}
.nav a {
  position:relative;
  font-weight:500;
  padding:0.35rem 0.5rem;
  text-decoration:none;
  color: var(--color-text);
}
/* Underline animation on hover */
.nav a::after {
  content:'';
  position:absolute;
  left:0;
  bottom:-4px;
  width:0;
  height:3px;
  background: var(--color-aqua-green);
  border-radius:2px;
  transition: width .3s;
}
.nav a:hover::after { width:100%; }

.user-journey {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 2rem;
  background: var(--color-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  position: relative;
}

.user-journey h2 {
  color: var(--color-blue);
  font-size: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}

/* Journey container with vertical line */
.journey-steps {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 3rem;
  padding-left: 3rem;
}

.journey-steps::before {
  content: "";
  position: absolute;
  left: 1.3rem;
  top: 0;
  bottom: 0;
  width: 4px;
  background: rgba(0, 200, 185, 0.2);
  z-index: 0;
}

.step {
  position: relative;
  background: var(--color-background);
  border-radius: var(--radius);
  padding: 1.5rem 1.5rem 1.5rem 4rem;
  border: 1px solid rgba(0,0,0,0.05);
  transition: transform 0.3s ease;
}
.step:hover {
  transform: translateY(-5px);
}

.icon-dot {
  position: absolute;
  left: -0.2rem;
  top: 1.2rem;
  width: 1.5rem;
  height: 1.5rem;
  background: var(--color-card);
  border: 3px solid var(--color-aqua-green);
  border-radius: 50%;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.icon-dot svg {
  width: 0.9rem;
  height: 0.9rem;
  fill: var(--color-aqua-green);
}

.icon-dot.filled {
  background: var(--color-aqua-green);
}
.icon-dot.filled svg {
  fill: white;
}

.step h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.step p {
  font-size: 1rem;
  line-height: 1.5;
}

.cta-buttons {
  margin-top: 2rem;
  text-align: center;
}

.cta-buttons a {
  display: inline-block;
  background: var(--color-blue);
  color: white;
  padding: 0.75rem 1.5rem;
  margin: 0.5rem;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: bold;
  transition: background 0.3s ease;
}
.cta-buttons a:hover {
  background: var(--color-aqua-green);
}

@media (min-width: var(--break-md)) {
  .journey-steps {
    padding-left: 4rem;
  }
}

/* Intro Section */
.intro-section {
  padding: 3rem 1.5rem;
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
}

.intro-section h1 {
  color: var(--color-blue);
  font-size: 2.2rem;
  margin-bottom: 1rem;
}

.intro-section p {
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
}

.intro-section ul {
  text-align: left;
  display: inline-block;
  margin: 1rem auto 2rem auto;
  padding-left: 1.2rem;
}

.intro-section li {
  margin-bottom: 0.75rem;
}

/* User Journey */
.journey {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1rem 5rem;
  position: relative;
}

.journey::before {
  content: '';
  position: absolute;
  left: 20px;
  top: 0;
  bottom: 0;
  width: 4px;
  background: linear-gradient(var(--color-aqua-green), var(--color-blue));
  transform-origin: top;
  transform: scaleY(0);
  transition: transform 1s ease-out;
}

.journey.active::before {
  transform: scaleY(1);
}

.step {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 3rem;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.step.visible {
  opacity: 1;
  transform: translateY(0);
}

.dot {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  background: var(--color-aqua-green);
  border-radius: 50%;
  border: 3px solid var(--color-blue);
  position: relative;
  margin-top: 0.3rem;
}

.step-content {
  background: var(--color-card);
  border-radius: var(--radius);
  padding: 1rem;
  box-shadow: var(--shadow);
}

.step-content h3 {
  margin-top: 0;
  color: var(--color-blue);
}
/* Call to Action */
.cta {
  background: var(--color-card);
  text-align: center;
  padding: 3rem 1rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin: 2rem auto;
  max-width: 900px;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.cta.visible {
  opacity: 1;
  transform: translateY(0);
}

.cta h2 {
  color: var(--color-blue);
  margin-bottom: 1rem;
}

.cta p {
  margin-bottom: 2rem;
}

.cta-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  text-decoration: none;
  color: white;
  transition: background var(--transition), transform 0.2s;
}

.btn-aqua {
  background: var(--color-aqua-green);
}

.btn-blue {
  background: var(--color-blue);
}

.btn:hover {
  transform: scale(1.05);
}
.comparison-section {
  background: var(--color-background);
  padding: 3rem 1rem;
  text-align: center;
}

.comparison-section h2 {
  color: var(--color-blue);
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.comparison-intro {
  font-size: 1.1rem;
  max-width: 700px;
  margin: 0 auto 2rem;
}

.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  max-width: 1000px; 
  margin: 0 auto;
}

.comparison-card {
  background: var(--color-card);
  padding: 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  text-align: left;
}

.comparison-card h3 {
  margin-bottom: 1rem;
  color: white;
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
}

.card-blue h3 {
  background: var(--color-blue);
}

.card-aqua h3 {
  background: var(--color-aqua-green);
}

.comparison-card ul {
  padding-left: 1.2rem;
}

.comparison-card ul li {
  margin-bottom: 0.75rem;
  font-size: 1rem;
}

/* =========================
   Footer Styles
   ========================= */
/* Footer with padding, background, and border */
.site-footer {
  padding:2rem 1rem;
  background: rgba(255,255,255,0.9);
  border-top:1px solid rgba(31,41,55,0.08);
}
.site-footer .inner {
  max-width:1120px;
  margin:0 auto;
  text-align:center;
  font-size:.9rem;
  color: var(--color-text);
}

/* Footer General */
.expanded-footer {
  background-color: var(--color-background);
  color: black;
  padding: 4rem 2rem 2rem;
  font-size: 0.95rem;
  line-height: 1.5;
}

.footer-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 2rem;
  max-width: 1200px;
  margin: 0 auto 2rem;
}

.footer-col {
  flex: 1 1 220px;
  min-width: 220px;
}

.footer-col h3 {
  margin-bottom: 1rem;
  font-size: 1.1rem;
  color: var(--color-blue);
}

.social-links {
  display: flex;
  gap: 1rem;
  padding: 0;
  list-style: none;
}

.social-links a {
  font-size: 2rem;
  color: black;
  transition: color 0.3s ease;
}

.social-links a:hover {
  color:var(--color-blue);
}

.newsletter-form {
  display: flex;
  border-radius: 5px;
  overflow: hidden;
  background-color: var(--color-background);
  border: var(--color-blue) 1px solid;
}

.newsletter-form input[type="email"] {
  flex: 1;
  padding: 0.6rem;
  border: none;
  background: transparent;
  color: var(--color-text);
}

.newsletter-form button {
  background: var(--color-blue);
  border: none;
  padding: 0 1rem;
  color: var(--color-background);
  cursor: pointer;
}

.membership-logos img {
  height: 50px;
  margin-right: 1rem;
}

.membership-logos a img {
  transition: transform 0.3s ease, filter 0.3s ease;
}

.membership-logos a:hover img {
  transform: scale(1.05);
  filter: brightness(1.2);
}


/* University Logos Section */
.university-logos-container {
  text-align: center;
  padding: 2rem 1rem 1rem;
  border-top: 1px solid #333;
}

.university-logos-container h3 {
  color: var(--color-blue);
  margin-bottom: 1rem;
}

.university-logos {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
}

.university-logos img {
  height: 50px;
  object-fit: contain;
  filter: brightness(0.9);
}

.university-logos a img {
  transition: transform 0.3s ease, filter 0.3s ease;
}

.university-logos a:hover img {
  transform: scale(1.05);
  filter: brightness(1.2);
}

/* Disclaimer */
.footer-disclaimer {
  text-align: center;
  font-size: 0.8rem;
  color: black;
  margin-top: 2rem;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
  padding: 1rem;
  border-top: 1px solid #333;
}

/* Responsive for mobile */
@media (max-width: 768px) {
  .comparison-grid {
    grid-template-columns: 1fr;
  }
}

/* Responsive */
@media (min-width: 768px) {
  .journey::before {
    left: 50%;
    margin-left: -2px;
  }
  .step {
    flex-direction: row;
  }
  .dot {
    width: 24px;
    height: 24px;
  }
}

/* =========================
   Papers & Authors Menu Additions
   ========================= */
/* THIS IS THE KEY PART OF THE CSS ABOUT GRAPHS */
/* Generic graph section wrapper */
.graph-section {
  padding: 2rem 1rem;
}

/* Card container for graphs/tables */
.graph-card {
  background: var(--color-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2rem;
  margin: 2rem auto;
  max-width: 1100px;
}

.graph-card h2 {
  color: var(--color-blue);
  margin-bottom: 1rem;
  text-align: center;
}

.graph-caption {
  font-size: 1rem;
  color: #555;
  margin-bottom: 1.5rem;
  text-align: center;
}

/* Responsive table */
.table-responsive {
  overflow-x: auto;
}

.styled-table {
  width: 100%;
  border-collapse: separate; 
  border-spacing: 0;      
  font-size: 1rem;
  border-radius: var(--radius);
  overflow: hidden;           
  box-shadow: var(--shadow);  
}

.styled-table th,
.styled-table td {
  border: 1px solid #ddd;
  padding: 0.75rem;
  text-align: left;
}

.styled-table th {
  background: var(--color-blue);
  color: white;
  text-align: center;
}

.styled-table td a {
  color: var(--color-aqua-green);
  text-decoration: none;
  font-weight: 500;
}

.styled-table td a:hover {
  text-decoration: underline;
}

/* Responsive tweaks */
@media (max-width: 768px) {
  .graph-card {
    padding: 1rem;
  }

  .styled-table th,
  .styled-table td {
    font-size: 0.9rem;
    padding: 0.5rem;
  }
}

#authors-per-year {
  width: 100%;
  aspect-ratio: 16 / 9;
  min-height: 400px; /* fallback for browsers without aspect-ratio support */
}

.collab-graphs {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
      justify-content: space-between;
    }
    .collab-graphs iframe {
      flex: 1 1 48%;
      min-width: 320px;
    }
    @media (max-width: 768px) {
      .collab-graphs {
        flex-direction: column;
      }
      .collab-graphs iframe {
        width: 100%;
      }
    }

/* =========================
   Extra Styles Applied
   ========================= */

/* Responsive iframe wrapper */
.responsive-iframe {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%; /* 16:9 ratio */
  height: 0;
  overflow: hidden;
}
.responsive-iframe iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* Collaboration graphs layout */
.collab-graphs {
  display: flex;
  flex-wrap: nowrap;
  gap: 2rem;
  justify-content: center;
}

.collab-graphs iframe {
  flex: 1 1 50%;
  min-width: 480px;
  height: 700px;
}

@media (max-width: 900px) {
  .collab-graphs {
    flex-direction: column;
  }
  .collab-graphs iframe {
    width: 100%;
    min-width: 100%;
    height: 500px;
  }
}

/* Collaboration stats highlights */
.collab-stats {
  margin: 2rem auto;
  text-align: center;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
}

.collab-stat {
  background: linear-gradient(135deg, var(--color-blue), var(--color-aqua-green));
  color: white;
  font-size: 1.3rem;
  font-weight: 700;
  padding: 1.5rem 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  flex: 1 1 260px;
  max-width: 320px;
  transition: transform 0.3s ease;
  justify-content: center;
  text-align: center;
  display: flex;
  align-items: center;
}

.collab-stat:hover {
  transform: translateY(-6px) scale(1.03);
}

/* VIDEOTUTORIAL */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease;
  z-index: 1000;
}

.modal.active {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  position: relative;
  width: 90%;
  max-width: 900px;
  background: #ffffff;
  border-radius: 12px;
  padding: 20px;
  transform: scale(0.9);
  transition: transform 0.3s ease;
}

.modal.active .modal-content {
  transform: scale(1);
}

.modal video {
  width: 100%;
  height: auto;
  border-radius: 8px;
}

.close {
  position: absolute;
  top: 12px;
  right: 15px;
  font-size: 28px;
  background: none;
  border: none;
  cursor: pointer;
}

.video-btn {
  background-color: #f2f2f2;
  color: #000000;
  border: 1px solid #cccccc;
  padding: 6px 12px;
  font-size: 13px;
  font-weight: 500;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.video-btn:hover {
  background-color: #e6e6e6;
  border-color: #999999;
}

.video-btn:active {
  transform: scale(0.97);
}