@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- ACADEMIC MINIMALIST LIGHT DESIGN SYSTEM --- */
:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-heading: 'Space Grotesk', var(--font-sans);
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Light Theme Academic Palette */
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --border-color: #e2e8f0;
  --border-hover: #cbd5e1;
  
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  
  --accent-cyan: #0284c7;   /* Academic Blue */
  --accent-violet: #6d28d9; /* Academic Purple */
  --accent-amber: #b45309;  /* Academic Amber/Orange */
  
  --transition-fast: all 0.2s ease-out;
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1140px;
}

/* --- RESET & BASIC STYLES --- */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scrollbar-color: var(--border-hover) var(--bg-base);
  scrollbar-width: thin;
}

body {
  background-color: var(--bg-base);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.6;
  overflow-x: hidden;
  padding: 3rem 0;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition-fast);
}

/* --- TYPOGRAPHY --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.25;
  color: var(--text-primary);
}

h2 {
  font-size: 1.6rem;
  font-weight: 700;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.5rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

p {
  color: var(--text-secondary);
}

.gradient-text {
  color: var(--accent-cyan);
}

/* --- APP CONTAINER & GRID --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.academic-grid {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 3.5rem;
  align-items: start;
}

/* --- LEFT COLUMN: SIDEBAR --- */
.sidebar {
  position: sticky;
  top: 3rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.profile-avatar-container {
  width: 220px;
  height: 220px;
  margin: 0 auto;
}

.profile-avatar {
  width: 100%;
  height: 100%;
  border-radius: 6px;
  object-fit: cover;
  border: 1px solid var(--border-color);
}

.profile-info {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.profile-name {
  font-size: 1.8rem;
  font-weight: 700;
  line-height: 1.15;
}

.profile-title-typing {
  font-size: 0.95rem;
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-weight: 600;
  min-height: 24px;
}

.profile-bio {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1.25rem;
}

.sidebar-contact-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  font-size: 0.9rem;
}

.contact-item {
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.contact-item a:hover {
  color: var(--accent-cyan);
}

.contact-item i {
  color: var(--text-muted);
  width: 16px;
  height: 16px;
}

/* --- RIGHT COLUMN: MAIN CONTENT --- */
.main-content {
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

/* Tab filter links */
.portfolio-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg-base);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.5rem;
  display: flex;
  gap: 1.25rem;
  margin-bottom: 1rem;
}

.nav-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.5rem 0.25rem;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.95rem;
  position: relative;
  transition: var(--transition-fast);
}

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

.nav-btn.active {
  color: var(--text-primary);
}

.nav-btn.active::after {
  content: '';
  position: absolute;
  bottom: -0.65rem;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--text-primary);
}

/* --- RESUME ENTRIES --- */
.resume-entry {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  transition: var(--transition-fast);
}

.resume-entry:hover {
  border-color: var(--border-hover);
  box-shadow: 0 4px 12px rgba(15, 23, 42, 0.04);
}

.entry-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1.5rem;
}

.entry-title-block {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.entry-icon {
  width: 48px;
  height: 48px;
  border-radius: 6px;
  object-fit: cover;
  border: 1px solid var(--border-color);
  background: #f1f5f9;
}

.entry-text-block {
  display: flex;
  flex-direction: column;
}

.entry-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
}

.entry-role {
  font-size: 0.85rem;
  color: var(--accent-cyan);
  font-weight: 600;
  font-family: var(--font-mono);
}

.entry-category-badge {
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: var(--text-secondary);
}

.entry-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.entry-desc ul {
  list-style: none;
  margin-top: 0.4rem;
  padding-left: 0.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.entry-desc li {
  position: relative;
  padding-left: 1.1rem;
}

.entry-desc li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent-cyan);
  font-weight: bold;
}

/* Badges section */
.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-top: 0.25rem;
}

.badge-label {
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  text-transform: uppercase;
  min-width: 80px;
}

.tech-badge {
  background: rgba(2, 132, 199, 0.05);
  border: 1px solid rgba(2, 132, 199, 0.15);
  color: var(--accent-cyan);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
}

.tech-badge.violet {
  background: rgba(109, 40, 217, 0.05);
  border-color: rgba(109, 40, 217, 0.15);
  color: var(--accent-violet);
}

.tech-badge.amber {
  background: rgba(180, 83, 9, 0.05);
  border-color: rgba(180, 83, 9, 0.15);
  color: var(--accent-amber);
}

.technique-badge {
  background: #f8fafc;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
}

.entry-links {
  display: flex;
  gap: 1rem;
  margin-top: 0.25rem;
  padding-top: 0.5rem;
  border-top: 1px dashed var(--border-color);
}

.entry-link {
  font-size: 0.8rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  color: var(--text-secondary);
}

.entry-link:hover {
  color: var(--accent-cyan);
}

/* --- INTERACTIVE COLLAPSIBLE VISUALIZER --- */
.visualizer-card {
  margin-bottom: 1.5rem;
}

.visualizer-toggle-btn {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  width: 100%;
  padding: 0.8rem 1.25rem;
  border-radius: 8px;
  color: var(--text-secondary);
  font-family: var(--font-heading);
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition-fast);
}

.visualizer-toggle-btn:hover {
  border-color: var(--accent-cyan);
  color: var(--text-primary);
}

.visualizer-content {
  display: none;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 1.5rem;
  margin-top: 1rem;
  animation: fadeIn 0.25s ease-out;
}

.visualizer-content.active {
  display: grid;
}

.visualizer-container {
  border: 1px solid var(--border-color);
  background: #ffffff;
  border-radius: 8px;
  overflow: hidden;
  aspect-ratio: 1.6 / 1;
}

.network-svg {
  width: 100%;
  height: 100%;
}

.net-link {
  stroke: #cbd5e1;
  stroke-width: 1.25px;
  stroke-dasharray: 4 4;
}
.net-link.active {
  stroke: rgba(2, 132, 199, 0.3);
  animation: dash 25s linear infinite;
}

.net-node {
  fill: #ffffff;
  stroke-width: 2px;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.net-node-core { stroke: var(--accent-violet); }
.net-node-pharos { stroke: var(--accent-cyan); }
.net-node-client { stroke: var(--text-muted); }

.net-node:hover, .net-node.active {
  fill: #f1f5f9;
  stroke-width: 3px;
  r: 8;
}

.net-node-core:hover, .net-node-core.active { r: 12; stroke: #8b5cf6; }
.net-node-pharos:hover, .net-node-pharos.active { r: 10; stroke: #06b6d4; }

.packet { fill: var(--accent-cyan); }
.packet-violet { fill: var(--accent-violet); }

.signal-wave {
  stroke: rgba(2, 132, 199, 0.4);
  stroke-width: 0.75px;
  fill: none;
  opacity: 0;
  transform-origin: 250px 150px;
  animation: pulse-wave 3s infinite linear;
}
.signal-wave:nth-child(2) { animation-delay: 1s; }
.signal-wave:nth-child(3) { animation-delay: 2s; }

.visualizer-details {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.details-card {
  padding: 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
}

.details-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.details-header i {
  color: var(--accent-cyan);
}

.details-grid {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.details-row {
  display: flex;
  justify-content: space-between;
  border-bottom: 1px dashed var(--border-color);
  padding-bottom: 0.2rem;
  font-size: 0.8rem;
}

.details-label { color: var(--text-secondary); }
.details-value { font-family: var(--font-mono); color: var(--text-primary); }

/* Academic Terminal Styling (Light Console) */
.diagnostic-console {
  background: #f8fafc;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-primary);
  height: 90px;
  overflow-y: auto;
}

.console-line {
  margin-bottom: 0.2rem;
  white-space: pre-wrap;
}

.console-line.cyan {
  color: var(--accent-cyan);
}

/* --- TECHNICAL SKILLS MATRIX --- */
.skills-section {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 1.25rem;
}

.skills-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.25rem;
}

.skills-card h3 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.4rem;
}

.skills-card h3 i {
  color: var(--accent-cyan);
  font-size: 0.9rem;
}

.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.skill-chip {
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* --- FOOTER --- */
.footer {
  border-top: 1px solid var(--border-color);
  padding: 2.5rem 0;
  margin-top: 3.5rem;
}

.footer-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-copyright {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  font-size: 0.8rem;
}

.footer-links a {
  color: var(--text-muted);
}

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

/* --- KEYFRAME ANIMATIONS --- */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(3px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes dash {
  to { stroke-dashoffset: -1000; }
}

@keyframes pulse-wave {
  0% { r: 10px; opacity: 0.5; }
  100% { r: 250px; opacity: 0; }
}

/* --- RESPONSIVE STYLE --- */
@media (max-width: 868px) {
  body {
    padding: 1.5rem 0;
  }
  
  .academic-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  
  .sidebar {
    position: relative;
    top: 0;
    text-align: center;
    align-items: center;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 1.5rem;
  }
  
  .portfolio-nav {
    top: 0;
    justify-content: center;
    padding-top: 0.5rem;
  }
  
  .visualizer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-container {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}