/* ============================================
   Kanchi Gupta Personal Brand Design Variables (Linear.app Style)
   ============================================ */
:root {
  /* Default: Dark Theme */
  --bg: #08090a;
  --text: #f7f8f8;
  --muted: #8a8f98;
  --accent: #7170ff;
  --accent-rgb: 113, 112, 255;
  --card-bg: rgba(255, 255, 255, 0.02);
  --card-border: rgba(255, 255, 255, 0.08);
  --hero-gradient: linear-gradient(135deg, #7170ff 0%, #b0aeff 100%);
  --button-hover: #828fff;
  --input-bg: rgba(255, 255, 255, 0.02);
}

/* Light Theme overrides */
html.light {
  --bg: #f7f8f8;
  --text: #08090a;
  --muted: #62666d;
  --accent: #5e6ad2;
  --accent-rgb: 94, 106, 210;
  --card-bg: rgba(0, 0, 0, 0.015);
  --card-border: rgba(0, 0, 0, 0.06);
  --hero-gradient: linear-gradient(135deg, #5e6ad2 0%, #7170ff 100%);
  --button-hover: #7170ff;
  --input-bg: rgba(0, 0, 0, 0.02);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-feature-settings: "cv01", "ss03";
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.3s, color 0.3s;
  overflow-x: hidden;
  position: relative;
}

/* ---------- 3D Canvas Background & Ambient Glow Orbs ---------- */
#nodes-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: -1;
  opacity: 0.85;
}

.ambient-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(var(--accent-rgb), 0.08) 0%, rgba(0, 0, 0, 0) 70%);
  filter: blur(100px);
  z-index: -2;
  pointer-events: none;
  animation: floatOrb 25s infinite alternate ease-in-out;
}

html.light .ambient-glow {
  background: radial-gradient(circle, rgba(var(--accent-rgb), 0.04) 0%, rgba(0, 0, 0, 0) 70%);
}

.glow-1 {
  top: -10%;
  left: -200px;
}

.glow-2 {
  bottom: 10%;
  right: -200px;
  animation-duration: 35s;
  animation-delay: -5s;
}

@keyframes floatOrb {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(80px, 50px) scale(1.15); }
}

/* ---------- Navigation bar ---------- */
.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 2rem;
  position: sticky;
  top: 0;
  background: rgba(15, 15, 15, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  z-index: 100;
  transition: background 0.3s, border-color 0.3s;
}

html.light .nav {
  background: rgba(249, 249, 251, 0.7);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.nav-name {
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
  background: var(--hero-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.2s;
}

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

#theme-toggle {
  background: none;
  border: 1px solid var(--card-border);
  border-radius: 999px;
  font-size: 1rem;
  padding: 0.4rem 0.8rem;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

#theme-toggle:hover {
  background: var(--card-bg);
}

/* ---------- Hero ---------- */
.hero {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
  padding: 8rem 2rem 6rem;
}

.hero-greeting {
  color: var(--accent);
  font-weight: 600;
  font-size: 1.1rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.hero h1 {
  font-size: clamp(2.8rem, 8vw, 4.8rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  background: var(--hero-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-tagline {
  color: var(--muted);
  font-size: clamp(1.1rem, 3vw, 1.35rem);
  max-width: 680px;
  margin: 0 auto 2.5rem;
  font-weight: 450;
}

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

.button {
  display: inline-block;
  padding: 0.85rem 2rem;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform 0.15s, opacity 0.2s, background-color 0.2s;
  cursor: pointer;
}

.button.primary {
  background: var(--accent);
  color: #FFFFFF;
}

.button.primary:hover {
  background: var(--button-hover);
}

.button.secondary {
  background: transparent;
  border: 1px solid var(--card-border);
  color: var(--text);
}

.button.secondary:hover {
  background: var(--card-bg);
}

.button:active {
  transform: scale(0.98);
}

/* ---------- Content sections ---------- */
section {
  max-width: 900px;
  margin: 0 auto;
  padding: 5rem 2rem;
  border-bottom: 1px solid var(--card-border);
}

h2 {
  font-size: 2.2rem;
  font-weight: 750;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  text-align: center;
}

.section-subtitle {
  text-align: center;
  color: var(--muted);
  font-size: 1.1rem;
  margin-bottom: 3rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- About Section ---------- */
.about-content {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  font-size: 1.1rem;
  color: var(--muted);
  max-width: 720px;
  margin: 0 auto;
}

.about-content p {
  line-height: 1.7;
}

/* ---------- Active Projects Grid ---------- */
.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}

.project-card:hover {
  transform: translateY(-4px);
  border-color: rgba(var(--accent-rgb), 0.4);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.project-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-bottom: 1rem;
}

.project-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}

.project-card p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.5;
  flex-grow: 1;
}

/* ---------- Resources Hub Section ---------- */
.resource-filters {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.filter-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  color: var(--muted);
  padding: 0.5rem 1.25rem;
  border-radius: 6px;
  font-weight: 550;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.2s;
}

.filter-btn:hover {
  color: var(--text);
  border-color: var(--muted);
}

.filter-btn.active {
  background: var(--accent);
  color: #FFFFFF;
  border-color: var(--accent);
}

.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.resource-card {
  background: rgba(26, 26, 26, 0.45);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.3s, box-shadow 0.4s, background 0.3s;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.resource-card:hover {
  transform: translateY(-6px);
  border-color: rgba(var(--accent-rgb), 0.5);
  box-shadow: 0 12px 40px rgba(var(--accent-rgb), 0.12);
  background: rgba(26, 26, 26, 0.65);
}

.resource-card.hidden {
  opacity: 0;
  transform: scale(0.95);
  display: none;
}

.resource-category {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 0.5rem;
  display: block;
}

.resource-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}

.resource-card p {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.5;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.resource-format {
  align-self: flex-start;
  font-size: 0.75rem;
  font-weight: 700;
  background: rgba(var(--accent-rgb), 0.1);
  color: var(--accent);
  padding: 0.25rem 0.75rem;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.resource-link {
  align-self: flex-start;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
  transition: opacity 0.2s;
}

.resource-link:hover {
  opacity: 0.8;
}

/* ---------- Contact Section ---------- */
#contact {
  text-align: center;
  border-bottom: none;
}

#contact p {
  color: var(--muted);
  font-size: 1.1rem;
  margin-bottom: 2.5rem;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.contact-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  padding: 1.25rem 2.5rem;
  border-radius: 8px;
  transition: transform 0.2s, border-color 0.2s;
  min-width: 240px;
}

.contact-item:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
}

.contact-item span {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}

.contact-item strong {
  font-size: 1.05rem;
  color: var(--text);
  font-weight: 600;
}

/* ---------- Footer ---------- */
footer {
  text-align: center;
  padding: 3rem 2rem;
  color: var(--muted);
  border-top: 1px solid var(--card-border);
  font-size: 0.9rem;
}

/* ---------- Mobile Optimization ---------- */
@media (max-width: 600px) {
  .nav {
    padding: 1rem 1.5rem;
  }
  .nav-links {
    gap: 1rem;
  }
  .hero {
    padding: 6rem 1.5rem 4rem;
  }
  section {
    padding: 4rem 1.5rem;
  }
  .contact-item {
    width: 100%;
  }
}