/* ============================================================
   Developer Portfolio Template - style.css
   Author  : Portfolio Template
   Version : 1.0
   Description: Dark-mode developer portfolio stylesheet with
                neon accents, smooth animations, and full
                Bootstrap 5 integration.
============================================================ */

/* ─── Google Fonts ──────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@300;400;500;600;700&family=Inter:wght@300;400;500;600;700;800;900&display=swap');

/* ─── CSS Custom Properties ─────────────────────────────── */
:root {
  --bg-primary   : #080f1a;
  --bg-secondary : #0d1b2e;
  --bg-card      : #0f2137;
  --bg-card-hover: #13293f;
  --accent-blue  : #00b4ff;
  --accent-green : #00ffb3;
  --accent-purple: #7b5ea7;
  --text-primary : #e8f4fd;
  --text-secondary: #8fa8c0;
  --text-muted   : #5c7a96;
  --border-color : rgba(0, 180, 255, 0.15);
  --glow-blue    : 0 0 20px rgba(0, 180, 255, 0.4);
  --glow-green   : 0 0 20px rgba(0, 255, 179, 0.4);
  --gradient-hero: linear-gradient(135deg, #080f1a 0%, #0d1b2e 50%, #071524 100%);
  --gradient-accent: linear-gradient(135deg, #00b4ff, #00ffb3);
  --gradient-btn : linear-gradient(135deg, #00b4ff 0%, #0077cc 100%);
  --font-code    : 'Fira Code', monospace;
  --font-sans    : 'Inter', sans-serif;
  --transition   : 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --radius       : 12px;
  --radius-lg    : 20px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

/* Custom scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--accent-blue); border-radius: 3px; }

/* ─── Selection ─────────────────────────────────────────── */
::selection { background: rgba(0, 180, 255, 0.25); color: #fff; }

/* ─── Typography Utilities ──────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.25;
}

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

a { color: var(--accent-blue); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-green); }

.font-mono { font-family: var(--font-code); }

/* Gradient text */
.gradient-text {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Section badge */
.section-badge {
  display: inline-block;
  font-family: var(--font-code);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent-blue);
  background: rgba(0, 180, 255, 0.1);
  border: 1px solid rgba(0, 180, 255, 0.3);
  border-radius: 50px;
  padding: 4px 16px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin-bottom: 1rem;
}

/* Section heading */
.section-title {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1rem;
  max-width: 560px;
}

/* ─── Buttons ───────────────────────────────────────────── */
.btn-neon {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--gradient-btn);
  color: #fff;
  font-weight: 600;
  font-size: 0.9rem;
  border: none;
  border-radius: 50px;
  padding: 12px 28px;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  transition: var(--transition);
  box-shadow: 0 4px 24px rgba(0, 180, 255, 0.35);
  letter-spacing: 0.3px;
}
.btn-neon::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(255,255,255,0.08);
  opacity: 0;
  transition: var(--transition);
}
.btn-neon:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(0, 180, 255, 0.55); color: #fff; }
.btn-neon:hover::before { opacity: 1; }

.btn-outline-neon {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: var(--accent-blue);
  font-weight: 600;
  font-size: 0.9rem;
  border: 2px solid var(--accent-blue);
  border-radius: 50px;
  padding: 10px 26px;
  cursor: pointer;
  transition: var(--transition);
  letter-spacing: 0.3px;
}
.btn-outline-neon:hover {
  background: rgba(0, 180, 255, 0.12);
  box-shadow: var(--glow-blue);
  color: var(--accent-blue);
  transform: translateY(-2px);
}

/* ─── Navbar ────────────────────────────────────────────── */
.navbar {
  background: rgba(8, 15, 26, 0.85) !important;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  padding: 14px 0;
  transition: var(--transition);
}
.navbar.scrolled {
  background: rgba(8, 15, 26, 0.97) !important;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.4);
}

.navbar-brand {
  font-family: var(--font-code);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary) !important;
}
.navbar-brand span { color: var(--accent-blue); }
.navbar-brand .cursor {
  display: inline-block;
  width: 2px;
  height: 1.1em;
  background: var(--accent-green);
  vertical-align: middle;
  margin-left: 2px;
  animation: blink 1s step-end infinite;
}

.navbar-nav .nav-link {
  color: var(--text-secondary) !important;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 6px 14px !important;
  position: relative;
  transition: color var(--transition);
  letter-spacing: 0.3px;
}
.navbar-nav .nav-link::after {
  content: '';
  position: absolute;
  bottom: 0; left: 50%; right: 50%;
  height: 2px;
  background: var(--gradient-accent);
  border-radius: 2px;
  transition: var(--transition);
}
.navbar-nav .nav-link:hover,
.navbar-nav .nav-link.active {
  color: var(--text-primary) !important;
}
.navbar-nav .nav-link:hover::after,
.navbar-nav .nav-link.active::after {
  left: 14px; right: 14px;
}

.navbar-toggler {
  border: 1px solid var(--border-color);
  color: var(--text-primary);
}
.navbar-toggler-icon {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(0,180,255,0.9)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

/* ─── Hero Section ──────────────────────────────────────── */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}

/* Animated grid background */
#hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 180, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 180, 255, 0.04) 1px, transparent 1px);
  background-size: 50px 50px;
  animation: gridMove 20s linear infinite;
}

/* Glowing orbs */
#hero::after {
  content: '';
  position: absolute;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(0, 180, 255, 0.08) 0%, transparent 70%);
  top: -100px; right: -100px;
  border-radius: 50%;
  animation: pulse 6s ease-in-out infinite;
}

.hero-content { position: relative; z-index: 2; }

.hero-greeting {
  font-family: var(--font-code);
  font-size: 1rem;
  color: var(--accent-green);
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 10px;
}
.hero-greeting::before { content: '// '; color: var(--text-muted); }

.hero-title {
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: 1rem;
}

.hero-title .typed-wrapper {
  display: block;
  color: var(--accent-blue);
  min-height: 1.15em;
}

.hero-description {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 520px;
  margin-bottom: 2rem;
  line-height: 1.8;
}

/* Code snippet card */
.code-snippet {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
  font-family: var(--font-code);
  font-size: 0.82rem;
  position: relative;
  overflow: hidden;
}
.code-snippet::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--gradient-accent);
}
.code-snippet .dot-bar {
  display: flex;
  gap: 6px;
  margin-bottom: 1rem;
}
.code-snippet .dot {
  width: 10px; height: 10px;
  border-radius: 50%;
}
.code-snippet .dot-red   { background: #ff5f57; }
.code-snippet .dot-yellow{ background: #febc2e; }
.code-snippet .dot-green { background: #28c840; }

.code-line { margin-bottom: 4px; }
.code-keyword  { color: #c792ea; }
.code-function { color: #82aaff; }
.code-string   { color: var(--accent-green); }
.code-comment  { color: var(--text-muted); font-style: italic; }
.code-variable { color: #f78c6c; }
.code-number   { color: #f07178; }

/* Stats row */
.hero-stats { margin-top: 2.5rem; }
.stat-item { text-align: left; }
.stat-number {
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}
.stat-label { font-size: 0.78rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-top: 4px; }

/* Scroll indicator */
.scroll-indicator {
  position: absolute;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-family: var(--font-code);
  animation: fadeInUp 1s 1.5s both;
  z-index: 2;
}
.scroll-mouse {
  width: 22px; height: 36px;
  border: 2px solid var(--border-color);
  border-radius: 11px;
  position: relative;
}
.scroll-mouse::after {
  content: '';
  position: absolute;
  top: 6px; left: 50%;
  transform: translateX(-50%);
  width: 3px; height: 6px;
  background: var(--accent-blue);
  border-radius: 3px;
  animation: scrollDown 1.8s ease-in-out infinite;
}

/* ─── Skills Section ────────────────────────────────────── */
#skills { padding: 100px 0; background: var(--bg-secondary); }

.skill-category-tabs .nav-link {
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: 50px;
  padding: 8px 22px;
  font-size: 0.85rem;
  font-weight: 500;
  margin: 4px;
  transition: var(--transition);
}
.skill-category-tabs .nav-link:hover,
.skill-category-tabs .nav-link.active {
  background: var(--gradient-btn);
  border-color: transparent;
  color: #fff;
  box-shadow: 0 4px 16px rgba(0, 180, 255, 0.3);
}

/* Skill icon card */
.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  transition: var(--transition);
  cursor: default;
  position: relative;
  overflow: hidden;
}
.skill-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-accent);
  opacity: 0;
  transition: var(--transition);
}
.skill-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 180, 255, 0.5);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3), var(--glow-blue);
}
.skill-card:hover::before { opacity: 0.05; }

.skill-icon {
  font-size: 2.5rem;
  margin-bottom: 0.75rem;
  display: block;
}
.skill-name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}
.skill-level {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-family: var(--font-code);
}

/* Progress bar */
.skill-bar-wrap { margin-bottom: 1.5rem; }
.skill-bar-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 8px;
}
.skill-bar-label { font-size: 0.875rem; font-weight: 500; color: var(--text-primary); }
.skill-bar-pct { font-size: 0.8rem; color: var(--accent-blue); font-family: var(--font-code); }
.progress {
  height: 6px;
  background: rgba(255,255,255,0.06);
  border-radius: 6px;
  overflow: hidden;
}
.progress-bar {
  background: var(--gradient-accent);
  border-radius: 6px;
  width: 0;
  transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 10px rgba(0, 180, 255, 0.5);
}

/* ─── Projects Section ──────────────────────────────────── */
#projects { padding: 100px 0; background: var(--bg-primary); }

.filter-tabs { margin-bottom: 2.5rem; }
.filter-btn {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  border-radius: 50px;
  padding: 7px 20px;
  font-size: 0.82rem;
  font-weight: 500;
  margin: 4px;
  cursor: pointer;
  transition: var(--transition);
}
.filter-btn:hover, .filter-btn.active {
  background: rgba(0, 180, 255, 0.12);
  border-color: var(--accent-blue);
  color: var(--accent-blue);
}

/* Project card */
.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
  height: 100%;
}
.project-card:hover {
  transform: translateY(-8px);
  border-color: rgba(0, 180, 255, 0.4);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4), var(--glow-blue);
}

.project-img-wrap {
  position: relative;
  overflow: hidden;
  height: 200px;
}
.project-img-wrap img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
  filter: brightness(0.85);
}
.project-card:hover .project-img-wrap img { transform: scale(1.08); filter: brightness(1); }

.project-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 30%, rgba(8, 15, 26, 0.95) 100%);
  display: flex;
  align-items: flex-end;
  padding: 1rem;
  opacity: 0;
  transition: var(--transition);
}
.project-card:hover .project-overlay { opacity: 1; }
.project-overlay-links { display: flex; gap: 8px; }
.project-overlay-links a {
  width: 36px; height: 36px;
  border-radius: 50%;
  background: rgba(0, 180, 255, 0.2);
  border: 1px solid rgba(0, 180, 255, 0.5);
  color: var(--accent-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  transition: var(--transition);
}
.project-overlay-links a:hover {
  background: var(--accent-blue);
  color: #fff;
}

.project-body { padding: 1.25rem 1.5rem 1.5rem; }
.project-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 0.75rem; }
.project-tag {
  font-family: var(--font-code);
  font-size: 0.68rem;
  background: rgba(0, 180, 255, 0.1);
  color: var(--accent-blue);
  border: 1px solid rgba(0, 180, 255, 0.25);
  border-radius: 4px;
  padding: 2px 8px;
  letter-spacing: 0.5px;
}
.project-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}
.project-desc { font-size: 0.84rem; color: var(--text-secondary); line-height: 1.6; }

/* ─── Experience Section ────────────────────────────────── */
#experience { padding: 100px 0; background: var(--bg-secondary); }

.timeline { position: relative; padding-left: 30px; }
.timeline::before {
  content: '';
  position: absolute;
  left: 0; top: 8px; bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--accent-blue), var(--accent-green), transparent);
  border-radius: 2px;
}

.timeline-item { position: relative; margin-bottom: 2.5rem; }
.timeline-item::before {
  content: '';
  position: absolute;
  left: -37px; top: 8px;
  width: 14px; height: 14px;
  background: var(--accent-blue);
  border: 3px solid var(--bg-secondary);
  border-radius: 50%;
  box-shadow: var(--glow-blue);
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem 1.75rem;
  transition: var(--transition);
  position: relative;
}
.timeline-card:hover {
  border-color: rgba(0, 180, 255, 0.4);
  box-shadow: 0 8px 32px rgba(0,0,0,0.3);
  transform: translateX(4px);
}

.timeline-period {
  font-family: var(--font-code);
  font-size: 0.75rem;
  color: var(--accent-green);
  background: rgba(0, 255, 179, 0.08);
  border: 1px solid rgba(0, 255, 179, 0.2);
  border-radius: 4px;
  padding: 2px 10px;
  display: inline-block;
  margin-bottom: 0.75rem;
}
.timeline-position {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}
.timeline-company {
  font-size: 0.9rem;
  color: var(--accent-blue);
  font-weight: 500;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 6px;
}
.timeline-desc { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.7; margin-bottom: 1rem; }

.timeline-tech { display: flex; flex-wrap: wrap; gap: 6px; }
.timeline-tech span {
  font-family: var(--font-code);
  font-size: 0.68rem;
  background: rgba(123, 94, 167, 0.15);
  color: #b48ece;
  border: 1px solid rgba(123, 94, 167, 0.3);
  border-radius: 4px;
  padding: 2px 8px;
}

/* ─── Testimonials Section ──────────────────────────────── */
#testimonials { padding: 100px 0; background: var(--bg-primary); }

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  height: 100%;
  position: relative;
  overflow: hidden;
  transition: var(--transition);
}
.testimonial-card::before {
  content: '"';
  position: absolute;
  top: -10px; right: 24px;
  font-size: 8rem;
  color: rgba(0, 180, 255, 0.06);
  font-family: Georgia, serif;
  line-height: 1;
  pointer-events: none;
}
.testimonial-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 180, 255, 0.3);
  box-shadow: 0 16px 48px rgba(0,0,0,0.3);
}

.testimonial-stars { color: #ffc107; font-size: 0.85rem; margin-bottom: 1rem; letter-spacing: 2px; }
.testimonial-text { font-size: 0.92rem; color: var(--text-secondary); line-height: 1.8; margin-bottom: 1.5rem; font-style: italic; }

.testimonial-author { display: flex; align-items: center; gap: 12px; }
.testimonial-avatar {
  width: 48px; height: 48px;
  border-radius: 50%;
  border: 2px solid var(--accent-blue);
  object-fit: cover;
}
.testimonial-name { font-size: 0.9rem; font-weight: 700; color: var(--text-primary); }
.testimonial-role { font-size: 0.77rem; color: var(--text-muted); font-family: var(--font-code); }

/* ─── Contact Section ───────────────────────────────────── */
#contact { padding: 100px 0; background: var(--bg-secondary); }

.contact-info-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 1.75rem;
}
.contact-icon-wrap {
  width: 48px; height: 48px;
  background: rgba(0, 180, 255, 0.1);
  border: 1px solid rgba(0, 180, 255, 0.25);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--accent-blue);
  flex-shrink: 0;
}
.contact-info-label { font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 2px; }
.contact-info-value { font-size: 0.9rem; color: var(--text-primary); font-weight: 500; }

/* Contact form */
.contact-form-wrap {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
}

.form-control, .form-select {
  background: rgba(255,255,255,0.04) !important;
  border: 1px solid var(--border-color) !important;
  color: var(--text-primary) !important;
  border-radius: var(--radius) !important;
  padding: 12px 16px;
  font-size: 0.9rem;
  transition: var(--transition);
}
.form-control:focus, .form-select:focus {
  border-color: var(--accent-blue) !important;
  box-shadow: 0 0 0 3px rgba(0, 180, 255, 0.15) !important;
  background: rgba(0, 180, 255, 0.04) !important;
  outline: none;
}
.form-control::placeholder { color: var(--text-muted); }
.form-label { font-size: 0.82rem; font-weight: 500; color: var(--text-secondary); margin-bottom: 6px; text-transform: uppercase; letter-spacing: 0.8px; }

textarea.form-control { resize: vertical; min-height: 130px; }

/* Social links */
.social-links { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 2rem; }
.social-link {
  width: 44px; height: 44px;
  border-radius: 50%;
  background: rgba(0, 180, 255, 0.1);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  transition: var(--transition);
}
.social-link:hover {
  background: var(--gradient-btn);
  border-color: transparent;
  color: #fff;
  transform: translateY(-3px);
  box-shadow: var(--glow-blue);
}

/* ─── Footer ────────────────────────────────────────────── */
footer {
  background: var(--bg-primary);
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
}
.footer-brand {
  font-family: var(--font-code);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
}
.footer-brand span { color: var(--accent-blue); }
.footer-copy { font-size: 0.82rem; color: var(--text-muted); }
.footer-links a { font-size: 0.82rem; color: var(--text-muted); margin-left: 1.25rem; transition: color var(--transition); }
.footer-links a:hover { color: var(--accent-blue); }

/* ─── Page Hero (inner pages) ───────────────────────────── */
.page-hero {
  padding: 140px 0 80px;
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
}
.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 180, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 180, 255, 0.04) 1px, transparent 1px);
  background-size: 50px 50px;
}

/* ─── Back to top ───────────────────────────────────────── */
#back-to-top {
  position: fixed;
  bottom: 30px; right: 30px;
  width: 44px; height: 44px;
  background: var(--gradient-btn);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 1rem;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 999;
  box-shadow: 0 4px 20px rgba(0, 180, 255, 0.4);
  transition: var(--transition);
}
#back-to-top.visible { display: flex; }
#back-to-top:hover { transform: translateY(-3px); box-shadow: 0 8px 30px rgba(0, 180, 255, 0.6); }

/* ─── Keyframe Animations ───────────────────────────────── */
@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50%       { transform: scale(1.1); opacity: 0.7; }
}

@keyframes gridMove {
  0%   { background-position: 0 0; }
  100% { background-position: 50px 50px; }
}

@keyframes scrollDown {
  0%   { top: 6px; opacity: 1; }
  100% { top: 20px; opacity: 0; }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInLeft {
  from { opacity: 0; transform: translateX(-30px); }
  to   { opacity: 1; transform: translateX(0); }
}

@keyframes fadeInRight {
  from { opacity: 0; transform: translateX(30px); }
  to   { opacity: 1; transform: translateX(0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-12px); }
}

/* Scroll reveal base */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-left { opacity: 0; transform: translateX(-30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal-left.visible { opacity: 1; transform: translateX(0); }
.reveal-right { opacity: 0; transform: translateX(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal-right.visible { opacity: 1; transform: translateX(0); }

/* Stagger delays */
.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }
.delay-4 { transition-delay: 0.4s; }
.delay-5 { transition-delay: 0.5s; }

/* Float animation on hero image */
.hero-img-float { animation: float 5s ease-in-out infinite; }

/* ─── Preloader ─────────────────────────────────────────── */
#preloader {
  position: fixed;
  inset: 0;
  background: var(--bg-primary);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 1rem;
  transition: opacity 0.5s ease;
}
#preloader.hidden { opacity: 0; pointer-events: none; }
.preloader-ring {
  width: 50px; height: 50px;
  border: 3px solid rgba(0, 180, 255, 0.2);
  border-top-color: var(--accent-blue);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
.preloader-text {
  font-family: var(--font-code);
  font-size: 0.8rem;
  color: var(--text-muted);
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ─── Toast notification ────────────────────────────────── */
.toast-notification {
  position: fixed;
  bottom: 30px; left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--bg-card);
  border: 1px solid var(--accent-green);
  border-radius: var(--radius);
  color: var(--accent-green);
  font-size: 0.85rem;
  font-family: var(--font-code);
  padding: 12px 24px;
  z-index: 9999;
  box-shadow: var(--glow-green);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.toast-notification.show { transform: translateX(-50%) translateY(0); }

/* ─── Responsive ────────────────────────────────────────── */
@media (max-width: 991.98px) {
  .navbar-collapse {
    background: rgba(8, 15, 26, 0.97);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1rem;
    margin-top: 0.5rem;
  }
  #hero { text-align: center; }
  .hero-description { margin: 0 auto 2rem; }
  .hero-greeting { justify-content: center; }
  .hero-stats .stat-item { text-align: center; }
  .hero-btn-group { justify-content: center !important; }
}

@media (max-width: 767.98px) {
  section { padding: 70px 0 !important; }
  .section-title { font-size: 1.8rem; }
  .code-snippet { display: none; }
  .contact-form-wrap { padding: 1.5rem; }
}