/* ================= LIQUID GLASS DESIGN SYSTEM ================= */

/* ========== DESIGN TOKENS ========== */
:root {
  /* Background colors (light theme) */
  --bg-primary: #ffffff;
  --bg-secondary: #f5f5f5;
  --bg-tertiary: #eeeeee;

  /* Primary Accent Color */
  --accent-primary: #2979FF;
  --accent-primary-dim: rgba(41, 121, 255, 0.06);
  --accent-primary-light: rgba(41, 121, 255, 0.12);

  /* Text colors */
  --text-primary: #0b0b0b;
  --text-secondary: #4a4a4a;
  --text-tertiary: #6b6b6b;

  /* Glass Effects */
  --glass-bg: rgba(255,255,255,0.9);
  --glass-border: rgba(16,16,16,0.06);
  --glass-blur: blur(6px);
  --glass-shadow: 0 6px 20px rgba(16,16,16,0.06);
  --surface-bg: linear-gradient(180deg, rgba(255,255,255,0.92), rgba(245,245,245,0.9));
  --surface-bg-soft: linear-gradient(135deg, rgba(255,255,255,0.92), rgba(245,245,245,0.9));
  --surface-bg-strong: linear-gradient(180deg, rgba(255,255,255,0.95), rgba(245,245,245,0.92));
  --surface-border: rgba(16,16,16,0.06);
  --surface-shadow: 0 6px 20px rgba(16,16,16,0.06);
  --page-noise-color: rgba(0,0,0,0.02);
  --preview-image-overlay: rgba(255,255,255,0.84);

  /* Spacing & Layout */
  --radius-main: 12px;
  --radius-round: 50px;
  --container-width: 1200px;

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);

  /* Logo accents */
  --logo-accent: #FFD166;
  --logo-accent-dim: rgba(255,209,102,0.12);
  --logo-bg-start: #ffffff;
  --logo-bg-end: #f2f2f2;
}

.dark-theme {
  /* Background colors (dark theme) */
  --bg-primary: #050505;
  --bg-secondary: #0d0d0d;
  --bg-tertiary: #141414;

  /* Text colors */
  --text-primary: #ffffff;
  --text-secondary: rgba(255,255,255,0.75);
  --text-tertiary: rgba(255,255,255,0.5);

  /* Glass Effects */
  --glass-bg: rgba(20,20,20,0.7);
  --glass-border: rgba(255,255,255,0.08);
  --glass-blur: blur(16px);
  --glass-shadow: 0 10px 40px rgba(0,0,0,0.4);
  --surface-bg: linear-gradient(180deg, rgba(24,24,24,0.92), rgba(15,15,15,0.9));
  --surface-bg-soft: linear-gradient(135deg, rgba(28,28,28,0.92), rgba(18,18,18,0.9));
  --surface-bg-strong: linear-gradient(180deg, rgba(34,34,34,0.95), rgba(20,20,20,0.92));
  --surface-border: rgba(255,255,255,0.08);
  --surface-shadow: 0 10px 40px rgba(0,0,0,0.4);
  --page-noise-color: rgba(255,255,255,0.02);
  --preview-image-overlay: rgba(8,8,8,0.72);

  /* Logo Background */
  --logo-bg-start: #0d0d0d;
  --logo-bg-end: #141414;
}


/* ========== RESET & BASE ========== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  opacity: 0;
  animation: fadeIn 0.6s ease forwards;
  margin: 0;
  padding: 0;
  overflow-x: hidden;

}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: radial-gradient(circle at 10% 20%, var(--page-noise-color) 0%, transparent 20%),
              radial-gradient(circle at 90% 80%, var(--page-noise-color) 0%, transparent 20%);
  pointer-events: none;
  z-index: -1;
}

body.reaction-active {
  opacity: 0;
  filter: blur(5px);
  transition: opacity 0.5s ease, filter 0.5s ease;
}

@keyframes fadeIn {
  from { opacity: 0; filter: blur(5px); }
  to { opacity: 1; filter: blur(0); }
}

/* ========== TYPOGRAPHY ========== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.2;
}

h1 {
  font-size: 3.5rem;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  transition: var(--transition-smooth);
}

h1:hover {
  text-shadow: 0 0 6px rgba(0,0,0,0.06);
}

h2 {
  font-size: 2rem;
  padding-left: 1rem;
  border-left: 3px solid var(--accent-primary);
  margin-bottom: 1.5rem;
}

h3 {
  font-size: 1.25rem;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  max-width: 70ch;
}

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

/* ========== UTILITIES: LIQUID GLASS ========== */
.liquid-glass {
  background: var(--surface-bg);
  backdrop-filter: blur(12px) saturate(150%);
  -webkit-backdrop-filter: blur(12px) saturate(150%);
  border: 2px solid var(--accent-primary-dim);
  box-shadow: 
    0 8px 30px rgba(0, 0, 0, 0.1),
    0 0 15px var(--accent-primary-dim);
  
  border-radius: var(--radius-main);
  background: linear-gradient(
    145deg,
    rgba(255, 255, 255, 0.05),
    rgba(255, 255, 255, 0.15)
  ), var(--surface-bg);
  
  transition: var(--transition-smooth);
  cursor: pointer;
}

.liquid-glass:not(.navbar) {
  overflow: hidden;
}

.liquid-glass:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow:
    0 12px 40px rgba(0, 0, 0, 0.15),
    0 0 25px var(--accent-primary-dim);
}


/* ========== BRAND LOGO ========== */
.nav-brand { display: flex; align-items: center; gap: 0.6rem; }

.brand-logo {
  height: 40px;
  width: 40px;
  display: inline-block;
  vertical-align: middle;
  border-radius: 50%;
  object-fit: cover;
  padding: 2px;
  background: linear-gradient(135deg, var(--logo-bg-start), var(--logo-bg-end));
  border: 2px solid rgba(255,255,255,0.6);
  box-shadow: 0 6px 18px rgba(16,16,16,0.06), 0 0 0 4px var(--logo-accent-dim);
  transition: transform .18s ease, box-shadow .18s ease;
}

.brand-logo:hover {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 10px 26px rgba(16,16,16,0.08), 0 0 0 6px var(--logo-accent-dim);
}

.footer-brand .brand-logo { height: 28px; width: 28px; }
.sr-only { position: absolute!important; height: 1px; width: 1px; overflow: hidden; clip: rect(1px,1px,1px,1px); white-space: nowrap; border: 0; padding: 0; margin: -1px; }

/* ========== NAVBAR ========== */
.navbar {
  position: sticky;
  top: 20px;
  z-index: 100;
  width: 90%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: -0.02em;
}

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

.nav-menu {
  display: flex;
  gap: 2rem;
}

.nav-link {
  color: var(--text-secondary);
  font-size: 0.95rem;
  position: relative;
  transition: color var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
  color: var(--accent-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  width: 0;
  height: 1px;
  bottom: -4px;
  left: 0;
  background-color: var(--accent-primary);
  transition: width var(--transition-fast);
}

.nav-link:hover::after {
  width: 100%;
}

/* Hide menu toggle by default (desktop) */
.menu-toggle {
  display: none;
}

/* Always show mode toggle */
.mode-toggle {
  display: flex;
}

/* Mobile-specific adjustments */
@media (max-width: 768px) {
  /* Show menu toggle on mobile */
  .menu-toggle {
    display: flex;
  }

  /* Navbar layout for mobile */
  .navbar {
    justify-content: space-between;
    padding: 0.6rem 1rem;
  }

  /* Controls container: mode toggle + menu toggle */
  .nav-controls {
    gap: 0.5rem;
  }

  /* Hide nav links initially on mobile */
  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-main);
    flex-direction: column;
    width: 180px;
    padding: 1rem;
    box-shadow: var(--glass-shadow);
  }

  .nav-menu.show {
    display: flex;
    margin-left: 180px;
  }
  /* Stack links vertically */
  .nav-link {
    margin: 0.5rem 0;
    text-align: right;
  }
}

.theme-btn {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  backdrop-filter: var(--glass-blur);
  padding: 0.5rem 0.9rem;
  border-radius: var(--radius-round);
  cursor: pointer;
  transition: var(--transition-fast);
}

.theme-btn:hover {
  transform: scale(1.05);
}


/* ========== BUTTONS ========== */
.btn {
  display: inline-block;
  padding: 0.8rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  border: 1px solid var(--accent-primary);
  color: var(--accent-primary);
  background: transparent;
  text-align: center;
  position: relative;
  overflow: hidden;
  text-decoration: none;
  border-radius: var(--radius-main);
  transition: all var(--transition-smooth);
}

.btn:hover {
  background: rgba(41, 121, 255, 0.1);
  box-shadow: 0 6px 18px rgba(41, 121, 255, 0.15);
  transform: translateY(-2px);
}

.btn-primary {
  display: inline-block;
  padding: 1rem 2rem;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid var(--accent-primary);
  color: #ffffff;
  background: var(--accent-primary);
  text-align: center;
  text-decoration: none;
  border-radius: var(--radius-main);
  transition: all var(--transition-smooth);
}

.btn-primary:hover {
  background: transparent;
  color: var(--accent-primary);
  box-shadow: 0 12px 30px rgba(41, 121, 255, 0.3);
  transform: translateY(-3px);
}

.btn-secondary {
  display: inline-block;
  padding: 1rem 2rem;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid var(--accent-primary);
  color: var(--accent-primary);
  background: transparent;
  text-align: center;
  text-decoration: none;
  border-radius: var(--radius-main);
  transition: all var(--transition-smooth);
}

.btn-secondary:hover {
  background: rgba(41, 121, 255, 0.1);
  box-shadow: 0 8px 24px rgba(41, 121, 255, 0.2);
  transform: translateY(-3px);
}

/* ========== HERO SECTION ========== */
/* .hero {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 0 20px;
  position: relative;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 3rem;
  max-width: 600px;
} */
/* =========================
   HERO SECTION
========================= */
/* ===================================================
   HERO HOME (INDEX PAGE ONLY)
   Requires: <section class="hero hero-home">
=================================================== */

.hero-home {
  position: relative;
  min-height: 100vh;
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem;
  overflow: hidden;
  background: var(--bg-primary);
}

/* ---------- Subtle Grid Background ---------- */

.hero-home .hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--accent-primary-dim) 1px, transparent 1px),
    linear-gradient(90deg, var(--accent-primary-dim) 1px, transparent 1px);
  background-size: 50px 50px;
  opacity: 0.4;
  z-index: 0;
  pointer-events: none;
}

/* ---------- Diethyl Ether Bird Molecule ---------- */

.hero-home .ether-bird {
  position: absolute;
  stroke: var(--accent-primary);
  fill: var(--accent-primary);
  stroke-width: 2;
  opacity: 0.08;
  pointer-events: none;
  z-index: 1;
}

/* Main molecule */
.hero-home .ether-main {
  width: 500px;
  animation: floatMain 28s ease-in-out infinite;
}

/* Background molecule */
.hero-home .ether-bg {
  width: 300px;
  opacity: 0.05;
  animation: floatBg 40s linear infinite reverse;
}

/* Atom Styling */
.hero-home .atom.oxygen {
  filter: drop-shadow(0 0 10px var(--accent-primary));
}

.hero-home .atom.carbon {
  opacity: 0.85;
}

/* Floating Animations */

@keyframes floatMain {
  0% { transform: translate(-30vw, 10vh) rotate(0deg); }
  50% { transform: translate(20vw, -5vh) rotate(6deg); }
  100% { transform: translate(80vw, 10vh) rotate(0deg); }
}

@keyframes floatBg {
  0% { transform: translate(90vw, -10vh) rotate(0deg); }
  100% { transform: translate(-40vw, 60vh) rotate(360deg); }
}

/* ---------- Glass Content Card ---------- */

.hero-home .hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
  padding: 3rem;
  text-align: center;
  border-radius: var(--radius-main);

  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);

  transition: var(--transition-smooth);
}

/* ---------- Title ---------- */

.hero-home .hero-title {
  font-size: 3rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  letter-spacing: 1px;
}

.hero-home .accent {
  color: var(--accent-primary);
}

/* ---------- Subtitle ---------- */

.hero-home .hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.6;
}

/* ---------- Button ---------- */

.hero-home .hero-btn {
  display: inline-block;
  padding: 0.9rem 2rem;
  border-radius: var(--radius-round);
  background: var(--accent-primary-light);
  border: 1px solid var(--accent-primary);
  color: var(--text-primary);
  text-decoration: none;
  transition: var(--transition-fast);
}

.hero-home .hero-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 0 20px var(--accent-primary-dim);
}

/* ---------- Responsive ---------- */

@media (max-width: 768px) {

  .hero-home .hero-content {
    padding: 2rem;
  }

  .hero-home .hero-title {
    font-size: 2rem;
  }

  .hero-home .hero-subtitle {
    font-size: 1rem;
  }

  .hero-home .ether-main {
    width: 250px;
  }

  .hero-home .ether-bg {
    width: 180px;
  }
}

/* =========================
   DEFAULT HERO (Inner Pages)
========================= */

.hero {
  padding: 6rem 2rem 3rem 2rem;
  text-align: center;
  background: var(--bg-primary);
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.hero-subtitle {
  max-width: 700px;
  margin: 0 auto;
  color: var(--text-secondary);
  font-size: 1.1rem;
  line-height: 1.6;
}

.hero-btn {
  padding: 0.8rem 2rem;
  border-radius: 50px;
  border: 1px solid rgba(41,121,255,0.6);
  background: rgba(41,121,255,0.08);
  color: var(--text-primary);
  text-decoration: none;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.hero-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 0 20px rgba(41,121,255,0.6);
  background: rgba(41,121,255,0.15);
}

/* ================= HERO HOME MOBILE FIX ================= */
@media (max-width: 768px) {

  /* Shrink hero height */
  .hero-home {
    min-height: auto; /* let content dictate height */
    padding: 3rem 1rem 2rem 1rem;
  }

  /* Center content without extra top/bottom margin */
  .hero-home .hero-content {
    padding: 2rem 1.5rem;
    max-width: 90%;
  }

  /* Adjust molecules so they don't overflow or leave extra space */
  .hero-home .ether-main {
    width: 200px;
    top: 10%;
    left: 50%;
    transform: translateX(-50%);
  }

  .hero-home .ether-bg {
    width: 120px;
  }

  /* Reduce subtitle spacing */
  .hero-home .hero-subtitle {
    margin-bottom: 1.5rem;
    font-size: 1rem;
  }

  /* Button scaling */
  .hero-home .hero-btn {
    padding: 0.7rem 1.5rem;
    font-size: 0.95rem;
  }
}




/* ========== SECTION CONTAINER ========== */
.section-container {
  max-width: var(--container-width);
  margin: 4rem auto;
  padding: 0 20px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.empty-card {
  padding: 1.5rem;
  border-radius: var(--radius-main);
  color: var(--text-secondary);
  border: 1px dashed rgba(41, 121, 255, 0.35);
}

/* ========== BLOG CARDS ========== */
.blog-card {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  height: 100%;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.blog-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-smooth);
}

.blog-card:hover::after {
  transform: scaleX(1);
}

.blog-card::before {
  content: attr(data-index);
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  font-family: monospace;
  color: var(--glass-border);
  font-size: 2rem;
  font-weight: 700;
  opacity: 0.5;
  transition: all var(--transition-smooth);
}

.blog-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 50px rgba(41, 121, 255, 0.2);
  transform: translateY(-8px);
}

.blog-card:hover::before {
  color: var(--accent-primary);
  opacity: 0.4;
  transform: scale(1.1);
}

.blog-date {
  font-size: 0.85rem;
  font-family: monospace;
  color: var(--text-tertiary);
  margin-bottom: 0.5rem;
}

.blog-title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
  line-height: 1.3;
}

.blog-card:hover .blog-title {
  color: var(--accent-primary);
}

.blog-preview {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  max-width: 70ch;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: var(--transition-fast);
  line-height: 1.5;
}

.card-footer {
  margin-top: auto;
  padding-top: 1.5rem;
  opacity: 0.7;
  transition: opacity var(--transition-smooth);
}

.blog-card:hover .card-footer {
  opacity: 1;
}

.read-link {
  font-size: 0.9rem;
  color: var(--accent-primary);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
}

.read-link:hover {
  gap: 0.8rem;
}

.blog-clickable {
  transition: all var(--transition-smooth);
  cursor: pointer;
}

.blog-clickable:active {
  transform: scale(0.98);
}

/* ========== PROJECT CARDS ========== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  height: 100%;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.project-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-smooth);
}

.project-card:hover::after {
  transform: scaleX(1);
}

.project-card::before {
  content: attr(data-index);
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  font-family: monospace;
  color: var(--glass-border);
  font-size: 2rem;
  font-weight: 700;
  opacity: 0.5;
  transition: all var(--transition-smooth);
}

.project-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 50px rgba(41, 121, 255, 0.2);
  transform: translateY(-8px);
}

.project-card:hover::before {
  color: var(--accent-primary);
  opacity: 0.4;
  transform: scale(1.1);
}

.project-date {
  font-size: 0.85rem;
  font-family: monospace;
  color: var(--text-tertiary);
  margin-bottom: 0.5rem;
  display: block;
}

.project-title {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
  line-height: 1.3;
}

.project-card:hover .project-title {
  color: var(--accent-primary);
}

.project-preview {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  max-width: 70ch;
  line-height: 1.5;
  flex-grow: 1;
}

.project-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.project-tag {
  display: inline-block;
  padding: 0.35rem 0.8rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(41, 121, 255, 0.3);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.project-card:hover .project-tag {
  background: rgba(41, 121, 255, 0.15);
  border-color: rgba(41, 121, 255, 0.5);
  transform: translateY(-2px);
}

.project-footer {
  display: flex;
  gap: 1rem;
  margin-top: auto;
  flex-wrap: wrap;
}

.project-link {
  font-size: 0.9rem;
  color: var(--accent-primary);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.project-link:hover {
  gap: 0.8rem;
}

/* ========== COURSE CARDS ========== */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.course-card {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  height: 100%;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.course-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-smooth);
}

.course-card:hover::after {
  transform: scaleX(1);
}

.course-card::before {
  content: attr(data-index);
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  font-family: monospace;
  color: var(--glass-border);
  font-size: 2rem;
  font-weight: 700;
  opacity: 0.5;
  transition: all var(--transition-smooth);
}

.course-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 50px rgba(41, 121, 255, 0.2);
  transform: translateY(-8px);
}

.course-card:hover::before {
  color: var(--accent-primary);
  opacity: 0.4;
  transform: scale(1.1);
}

.course-level {
  display: inline-block;
  padding: 0.35rem 0.8rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(41, 121, 255, 0.3);
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.course-title {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
  line-height: 1.3;
}

.course-card:hover .course-title {
  color: var(--accent-primary);
}

.course-preview {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  max-width: 70ch;
  line-height: 1.5;
  flex-grow: 1;
}

.course-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
  color: var(--text-tertiary);
}

.course-duration,
.course-difficulty {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: color var(--transition-fast);
}

.course-card:hover .course-duration,
.course-card:hover .course-difficulty {
  color: var(--accent-primary);
}

.course-topics {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.course-topic {
  display: inline-block;
  padding: 0.35rem 0.8rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(41, 121, 255, 0.3);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.course-card:hover .course-topic {
  background: rgba(41, 121, 255, 0.15);
  border-color: rgba(41, 121, 255, 0.5);
  transform: translateY(-2px);
}

.course-link {
  display: inline-block;
  font-size: 0.9rem;
  color: var(--accent-primary);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
  padding: 0.8rem 1.5rem;
  border: 1px solid var(--accent-primary);
  background: transparent;
  border-radius: var(--radius-main);
  cursor: pointer;
}

.course-link:hover {
  background: rgba(41, 121, 255, 0.1);
  border-color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(41, 121, 255, 0.15);
}

/* ========== ABOUT PAGE ========== */
.about-button-section {
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 6rem auto;
}

.about-btn {
  padding: 1.2rem 2.5rem !important;
  font-size: 1.1rem !important;
  font-weight: 600 !important;
  border: 2px solid var(--accent-primary) !important;
  color: var(--accent-primary) !important;
  background: var(--surface-bg-strong) !important;
  backdrop-filter: blur(6px) saturate(120%) !important;
  -webkit-backdrop-filter: blur(6px) saturate(120%) !important;
  box-shadow: 0 8px 24px rgba(41, 121, 255, 0.1) !important;
  transition: var(--transition-smooth) !important;
  text-decoration: none;
  display: inline-block;
  cursor: pointer;
  border-radius: var(--radius-main) !important;
}

.about-btn:hover {
  border-color: var(--accent-primary) !important;
  background: linear-gradient(180deg, rgba(41, 121, 255, 0.06), rgba(41, 121, 255, 0.04)) !important;
  box-shadow: 0 12px 32px rgba(41, 121, 255, 0.2) !important;
  transform: translateY(-4px) !important;
}

.about-hero {
  background: var(--surface-bg-soft);
  padding: 3rem;
  border-radius: var(--radius-main);
  margin-bottom: 3rem;
  border: 1px solid var(--surface-border);
  box-shadow: var(--surface-shadow);
}

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

.about-hero-photo {
  display: flex;
  justify-content: center;
  align-items: center;
}

.photo-frame {
  position: relative;
  width: 280px;
  height: 280px;
}

.photo-frame-border {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 3px solid var(--accent-primary);
  opacity: 0.3;
  animation: rotateFrame 20s linear infinite;
}

@keyframes rotateFrame {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.profile-photo {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--accent-primary);
  box-shadow: 0 20px 60px rgba(41, 121, 255, 0.3), inset 0 0 30px rgba(41, 121, 255, 0.1);
  transition: all var(--transition-smooth);
  position: relative;
  z-index: 1;
}

.profile-photo:hover {
  box-shadow: 0 30px 80px rgba(41, 121, 255, 0.4), inset 0 0 30px rgba(41, 121, 255, 0.15);
  transform: scale(1.02);
}

.about-hero-info h1 {
  font-size: 2.8rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  border: none;
  padding: 0;
}

.about-hero-subtitle {
  font-size: 1.1rem;
  color: var(--accent-primary);
  font-weight: 600;
  margin-bottom: 1.5rem;
  letter-spacing: 0.5px;
}

.about-hero-bio {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 2rem;
  max-width: 500px;
}

.about-hero-cta {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.about-section {
  margin-bottom: 2rem;
}

.about-section-icon {
  font-size: 2.5rem;
  color: var(--accent-primary);
  margin-bottom: 1rem;
  opacity: 0.8;
}

.about-section-content {
  padding: 2rem;
}

.about-section-content h2 {
  font-size: 1.8rem;
  border: none;
  padding: 0;
  margin-bottom: 1.5rem;
}

.about-section-content p {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 1rem;
}

.about-values-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.value-card {
  padding: 2rem;
  text-align: center;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.value-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 40px rgba(41, 121, 255, 0.15);
  transform: translateY(-5px);
}

.value-icon {
  font-size: 2.8rem;
  color: var(--accent-primary);
  margin-bottom: 1rem;
  transition: transform var(--transition-smooth);
}

.value-card:hover .value-icon {
  animation: spin 0.8s ease-in-out;
}

@keyframes spin {
  0% { transform: rotateY(0deg); }
  100% { transform: rotateY(360deg); }
}

.value-card h3 {
  font-size: 1.5rem;
  margin-bottom: 0.8rem;
  color: var(--text-primary);
}

.value-card p {
  color: var(--text-secondary);
  line-height: 1.7;
}

.about-highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3rem;
  padding: 2rem;
  text-align: center;
  background: var(--surface-bg-soft);
  border-radius: var(--radius-main);
  border: 1px solid var(--surface-border);
  box-shadow: var(--surface-shadow);
}

.highlight-item {
  padding: 1.5rem;
}

.highlight-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-primary);
  line-height: 1;
  margin-bottom: 0.5rem;
}

.highlight-label {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 600;
}

.skills-group {
  margin-bottom: 2rem;
  padding: 2rem;
  background: var(--surface-bg-soft);
  border-radius: var(--radius-main);
  border: 1px solid var(--surface-border);
  box-shadow: var(--surface-shadow);
}

.skills-group:last-child {
  margin-bottom: 0;
}

.skills-group h4 {
  font-size: 1.1rem;
  color: var(--text-primary);
  margin-bottom: 1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid rgba(41, 121, 255, 0.2);
}

.skills-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.skill-badge {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: linear-gradient(135deg, rgba(41, 121, 255, 0.1), rgba(41, 121, 255, 0.05));
  color: var(--accent-primary);
  border: 1px solid rgba(41, 121, 255, 0.4);
  border-radius: 20px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition-smooth);
}

.skill-badge:hover {
  background: var(--accent-primary);
  color: #ffffff;
  border-color: var(--accent-primary);
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 8px 16px rgba(41, 121, 255, 0.25);
}

.about-connect {
  text-align: center;
  padding: 3rem;
  margin-bottom: 3rem;
  background: linear-gradient(135deg, rgba(41, 121, 255, 0.05), rgba(41, 121, 255, 0.02));
  border-radius: var(--radius-main);
}

.about-connect h2 {
  border: none;
  padding: 0;
  margin-bottom: 1rem;
  font-size: 2rem;
}

.about-connect p {
  max-width: 600px;
  margin: 0 auto 2rem;
  font-size: 1rem;
  color: var(--text-secondary);
}

.connect-links {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.connect-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--accent-primary);
  border: 2px solid var(--accent-primary);
  background: transparent;
  border-radius: var(--radius-main);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.connect-btn:hover {
  background: var(--accent-primary);
  color: #ffffff;
  box-shadow: 0 12px 30px rgba(41, 121, 255, 0.3);
  transform: translateY(-3px);
}

/* ========== FOOTER ========== */
/* =========================
   Footer Styling
========================= */
.footer {
  margin-top: 4rem;
  padding: 3rem 1.5rem;
  border-top: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  box-shadow: var(--glass-shadow);
  text-align: center;
  position: relative;
  z-index: 10;
  transition: background 0.4s, color 0.4s;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* Gradient stripe on top */
.footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 80%;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-primary-dim));
  border-radius: 2px 2px 0 0;
}

/* Footer content flex */
.footer-content {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

/* Brand logo */
.footer-brand img.brand-logo {
  width: 50px;
  height: auto;
  transition: transform 0.3s ease;
}

.footer-brand:hover img.brand-logo {
  transform: scale(1.1);
}

/* Footer links */
.footer-link {
  color: var(--text-secondary);
  font-size: 0.9rem;
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

/* Accent underline on hover */
.footer-link::after {
  content: "";
  display: block;
  width: 0%;
  height: 2px;
  background: var(--accent-primary);
  transition: width 0.3s ease;
  position: absolute;
  bottom: -2px;
  left: 0;
}

.footer-link:hover::after {
  width: 100%;
}

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

/* Copyright */
.footer .copyright {
  color: var(--text-tertiary);
  font-size: 0.8rem;
  margin: 0.3rem 0 0 0;
}

/* Made with love */
.footer .made-with-love {
  color: var(--text-tertiary);
  font-size: 0.8rem;
  margin: 0.2rem 0 0 0;
}

/* =========================
   Mobile Adjustments
========================= */
@media (max-width: 768px) {
  .footer-content {
    flex-direction: column;
    gap: 0.8rem;
    align-items: center;
  }

  .footer-brand img.brand-logo {
    width: 40px;
  }
}



/* ========== RESPONSIVE DESIGN ========== */
@media (max-width: 768px) {
  h1 { font-size: 2.5rem; }
  h2 { font-size: 1.75rem; }

  .navbar {
    width: 95%;
    padding: 1rem;
  }

  .nav-menu {
    position: fixed;
    top: 80px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bg-secondary);
    padding: 2rem;
    gap: 1.5rem;
    border-bottom: 1px solid var(--glass-border);
    transform: translateY(-150%);
    transition: transform var(--transition-smooth);
    z-index: 99;
  }

  .nav-menu.active {
    transform: translateY(0);
  }

  .menu-toggle {
    display: block;
  }

  .grid-3 {
    grid-template-columns: 1fr;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }

  .courses-grid {
    grid-template-columns: 1fr;
  }

  .about-hero-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .about-hero {
    padding: 2rem;
  }

  .about-hero-info h1 {
    font-size: 2rem;
  }

  .about-hero-cta {
    gap: 1rem;
    flex-direction: column;
  }

  .btn-primary, .btn-secondary {
    padding: 0.8rem 1.5rem;
    font-size: 0.9rem;
    width: 100%;
    text-align: center;
  }

  .photo-frame {
    width: 220px;
    height: 220px;
  }

  .about-values-grid {
    grid-template-columns: 1fr;
  }

  .about-highlights {
    grid-template-columns: repeat(2, 1fr);
  }

  .connect-links {
    gap: 0.5rem;
    flex-direction: column;
  }

  .connect-btn {
    padding: 0.7rem 1.2rem;
    font-size: 0.85rem;
    width: 100%;
    justify-content: center;
  }
}

/* ========== COLLEGE ASSIGNMENTS ========== */
.college-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.assignment-card {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  height: 100%;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.assignment-card::before {
  content: attr(data-index);
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  font-family: monospace;
  color: var(--glass-border);
  font-size: 2rem;
  font-weight: 700;
  opacity: 0.5;
  transition: all var(--transition-smooth);
}

.assignment-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 50px rgba(41, 121, 255, 0.2);
  transform: translateY(-8px);
}

.assignment-card:hover::before {
  color: var(--accent-primary);
  opacity: 0.4;
  transform: scale(1.1);
}

.assignment-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid rgba(41, 121, 255, 0.15);
}

.assignment-course {
  display: inline-block;
  padding: 0.4rem 0.9rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
}

.assignment-date {
  font-size: 0.85rem;
  color: var(--text-tertiary);
  font-family: monospace;
}

.assignment-title {
  font-size: 1.4rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
  line-height: 1.3;
}

.assignment-card:hover .assignment-title {
  color: var(--accent-primary);
}

.assignment-description {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.6;
  flex-grow: 1;
}

.assignment-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.assignment-tag {
  display: inline-block;
  padding: 0.35rem 0.8rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(41, 121, 255, 0.3);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.assignment-card:hover .assignment-tag {
  background: rgba(41, 121, 255, 0.15);
  border-color: rgba(41, 121, 255, 0.5);
  transform: translateY(-2px);
}

.assignment-doc {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: auto;
}

.doc-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--accent-primary);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.doc-link:hover {
  gap: 0.8rem;
  text-decoration: underline;
}

/* ========== PRESENTATIONS ========== */
.presentations-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.presentation-card {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  height: 100%;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  transition: all var(--transition-smooth);
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
}

.presentation-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-smooth);
}

.presentation-card:hover::after {
  transform: scaleX(1);
}

.presentation-card::before {
  content: attr(data-index);
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  font-family: monospace;
  color: var(--glass-border);
  font-size: 2rem;
  font-weight: 700;
  opacity: 0.5;
  transition: all var(--transition-smooth);
}

.presentation-card:hover::before {
  color: var(--accent-primary);
  opacity: 0.4;
  transform: scale(1.1);
}

.presentation-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 50px rgba(41, 121, 255, 0.2);
  transform: translateY(-8px);
}

.presentation-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid rgba(41, 121, 255, 0.15);
}

.presentation-category {
  display: inline-block;
  padding: 0.4rem 0.9rem;
  background: rgba(41, 121, 255, 0.1);
  color: var(--accent-primary);
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
}

.presentation-date {
  font-size: 0.85rem;
  color: var(--text-tertiary);
  font-family: monospace;
}

.presentation-title {
  font-size: 1.4rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
  line-height: 1.3;
}

.presentation-card:hover .presentation-title {
  color: var(--accent-primary);
}

.presentation-desc {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.6;
  flex-grow: 1;
}

.presentation-stats {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  padding: 1rem;
  background: rgba(41, 121, 255, 0.05);
  border-radius: 8px;
  border: 1px solid rgba(41, 121, 255, 0.1);
}

.stat-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.stat-icon {
  font-size: 1.2rem;
}

.stat-text {
  font-weight: 500;
}

.presentation-actions {
  display: flex;
  gap: 1rem;
  margin-top: auto;
  flex-wrap: wrap;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1.2rem;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--radius-main);
  transition: all var(--transition-smooth);
  cursor: pointer;
  flex: 1;
  justify-content: center;
  border: 2px solid var(--accent-primary);
}

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

.download-btn:hover {
  background: transparent;
  color: var(--accent-primary);
  box-shadow: 0 6px 20px rgba(41, 121, 255, 0.3);
  transform: translateY(-2px);
}

.preview-btn {
  color: var(--accent-primary);
  background: transparent;
}

.preview-btn:hover {
  background: rgba(41, 121, 255, 0.1);
  box-shadow: 0 6px 20px rgba(41, 121, 255, 0.15);
  transform: translateY(-2px);
}

/* ========== TIPS GRID ========== */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.tip-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 2rem;
  background: var(--surface-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-main);
  box-shadow: var(--surface-shadow);
  transition: all var(--transition-smooth);
}

.tip-card:hover {
  border-color: var(--accent-primary);
  box-shadow: 0 12px 40px rgba(41, 121, 255, 0.15);
  transform: translateY(-5px);
}

.tip-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.tip-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.8rem;
  color: var(--text-primary);
}

.tip-card p {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 0;
}

/* ========== PREVIEW CARD BACKGROUND IMAGES ========== */
.has-bg-image {
  position: relative;
  background: var(--surface-bg);
}

.has-bg-image::before,
.has-bg-image::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
}

.has-bg-image::before {
  background-image: var(--preview-bg-image);
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
  z-index: 0;
}

.has-bg-image::after {
  background-image: linear-gradient(var(--preview-image-overlay), var(--preview-image-overlay));
  z-index: 1;
}

.has-bg-image > * {
  position: relative;
  z-index: 2;
}

/* ========== RESPONSIVE COLLEGE & PRESENTATIONS ========== */
@media (max-width: 768px) {
  .college-grid {
    grid-template-columns: 1fr;
  }

  .presentations-grid {
    grid-template-columns: 1fr;
  }

  .tips-grid {
    grid-template-columns: 1fr;
  }

  .assignment-card {
    padding: 1.5rem;
  }

  .presentation-card {
    padding: 1.5rem;
  }

  .presentation-stats {
    flex-direction: column;
    gap: 1rem;
  }

  .presentation-actions {
    flex-direction: column;
  }

  .action-btn {
    flex: none;
  }

  .assignment-doc {
    flex-direction: column;
  }

  .doc-link {
    width: 100%;
    justify-content: center;
  }
}

/* ========== MOBILE RESPONSIVE OVERRIDES (HOME + GRID PAGES) ========== */
.liquid-glass,
.hero-home .hero-content,
.blog-card,
.project-card,
.course-card,
.assignment-card,
.presentation-card,
.tip-card {
  transition: background 0.4s, color 0.4s, box-shadow 0.4s, border-color 0.4s, transform var(--transition-smooth);
}

@media (max-width: 768px) {
  .hero-home {
    min-height: auto;
    padding: 3rem 1rem 2rem 1rem;
    overflow: hidden;
  }

  .hero-home .hero-content {
    width: min(100%, 560px);
    max-width: 100%;
    margin: 0 auto;
    padding: 1.5rem 1rem;
    text-align: center;
  }

  .hero-home .ether-bird {
    max-width: 100vw;
  }

  .hero-home .ether-main {
    width: min(200px, 58vw);
    max-width: 200px;
  }

  .hero-home .ether-bg {
    width: min(120px, 34vw);
    max-width: 120px;
  }

  .hero-home .hero-subtitle {
    font-size: 1rem;
    margin-bottom: 1.5rem;
  }

  .hero-home .hero-btn {
    padding: 0.7rem 1.5rem;
    font-size: 0.95rem;
  }

  .section-container {
    padding: 0 1rem;
    margin: 2.5rem auto;
  }

  .grid-3,
  .projects-grid,
  .courses-grid,
  .college-grid,
  .presentations-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .blog-card,
  .project-card,
  .course-card,
  .assignment-card,
  .presentation-card,
  .tip-card {
    padding: 1rem;
  }

  .blog-preview,
  .project-preview,
  .course-preview,
  .assignment-description,
  .presentation-desc,
  .tip-card p,
  .stat-item,
  .read-link,
  .project-link,
  .course-link,
  .doc-link,
  .action-btn {
    font-size: 0.9rem;
  }

  .blog-title,
  .project-title,
  .course-title,
  .assignment-title,
  .presentation-title {
    font-size: 1.15rem;
  }

  .blog-card img,
  .project-card img,
  .course-card img,
  .assignment-card img,
  .presentation-card img {
    width: 100%;
    max-height: 150px;
    object-fit: cover;
    border-radius: calc(var(--radius-main) - 4px);
  }
}

/* Special for about.html */
.builder-hero-btn-container {
  display: flex;
  justify-content: center;
  margin: 2rem auto;
  width: 90%;
  max-width: var(--container-width);
}

.builder-hero-btn {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1.5rem 2rem;
  border-radius: var(--radius-main);
  background: var(--glass-bg);
  border: 3px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  backdrop-filter: blur(6px) saturate(120%);
  -webkit-backdrop-filter: blur(6px) saturate(120%);
  text-decoration: none;
  color: var(--text-primary);
  transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
}

.builder-hero-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 10px 30px rgba(41, 121, 255, 0.25);
  cursor: pointer;
}

.btn-content {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.btn-logo {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  border: 2px solid var(--accent-primary);
}

.btn-text h2 {
  margin: 0;
  font-size: 1.5rem;
}

.btn-text p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

/* Responsive */
@media (max-width: 600px) {
  .builder-hero-btn {
    flex-direction: column;
    text-align: center;
    padding: 1rem 1.5rem;
  }

  .btn-content {
    flex-direction: column;
    gap: 0.8rem;
  }

  .btn-logo {
    width: 50px;
    height: 50px;
  }
}