/* ==========================================================================
   Michael Beatty (mabeatty.com) — Personal Portfolio & Engineering Hub
   Modern, dynamic, glassmorphic design system
   ========================================================================== */

:root {
  /* Color Palette - Dark Theme (Default) */
  --bg-primary: #070b14;
  --bg-secondary: #0c1322;
  --bg-card: rgba(15, 23, 42, 0.65);
  --bg-card-hover: rgba(22, 33, 58, 0.85);
  --bg-glass: rgba(255, 255, 255, 0.03);
  --bg-glass-active: rgba(255, 255, 255, 0.08);

  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-accent: #38bdf8;

  --accent-cyan: #38bdf8;
  --accent-blue: #3b82f6;
  --accent-indigo: #6366f1;
  --accent-purple: #a855f7;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;

  --gradient-brand: linear-gradient(135deg, #38bdf8 0%, #6366f1 50%, #a855f7 100%);
  --gradient-surface: linear-gradient(180deg, rgba(255, 255, 255, 0.04) 0%, rgba(255, 255, 255, 0) 100%);
  --gradient-glow: radial-gradient(circle at 50% 0%, rgba(56, 189, 248, 0.15), transparent 70%);

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-card: rgba(255, 255, 255, 0.12);
  --border-glow: rgba(56, 189, 248, 0.4);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px -4px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 40px -10px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 35px -5px rgba(56, 189, 248, 0.25);

  --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-slow: 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Light Theme Variables */
[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #f1f5f9;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: rgba(255, 255, 255, 0.98);
  --bg-glass: rgba(0, 0, 0, 0.03);
  --bg-glass-active: rgba(0, 0, 0, 0.07);

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --text-accent: #0284c7;

  --border-subtle: rgba(0, 0, 0, 0.08);
  --border-card: rgba(0, 0, 0, 0.12);
  --border-glow: rgba(2, 132, 199, 0.4);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 8px 24px -4px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 20px 40px -10px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 35px -5px rgba(2, 132, 199, 0.2);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Ambient Background Lights & Grid */
.bg-ambient {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.ambient-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
  will-change: transform;
}

.ambient-orb-1 {
  width: 550px;
  height: 550px;
  background: radial-gradient(circle, #38bdf8 0%, transparent 70%);
  top: -150px;
  right: -100px;
  animation: floatOrb 22s ease-in-out infinite alternate;
}

.ambient-orb-2 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, #6366f1 0%, transparent 70%);
  bottom: 10%;
  left: -150px;
  animation: floatOrb 28s ease-in-out infinite alternate-reverse;
}

.ambient-orb-3 {
  width: 450px;
  height: 450px;
  background: radial-gradient(circle, #a855f7 0%, transparent 70%);
  top: 45%;
  right: 15%;
  opacity: 0.2;
}

.bg-grid-overlay {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(to right, var(--border-subtle) 1px, transparent 1px),
    linear-gradient(to bottom, var(--border-subtle) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(circle at 50% 30%, black 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(circle at 50% 30%, black 30%, transparent 80%);
  opacity: 0.5;
}

@keyframes floatOrb {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, -50px) scale(1.08); }
  100% { transform: translate(-30px, 30px) scale(0.95); }
}

/* Typography Utilities */
h1, h2, h3, h4, .font-heading {
  font-family: var(--font-heading);
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
}

.text-gradient {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

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

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

/* Layout Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* Navigation Header */
.header-nav {
  position: fixed;
  top: 16px;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 24px;
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-full);
  padding: 10px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.15rem;
}

.brand-badge {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 15px rgba(56, 189, 248, 0.3);
  position: relative;
  overflow: hidden;
}

.brand-badge::before {
  content: '';
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: var(--gradient-brand);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
}

.brand-initials {
  font-size: 0.95rem;
  font-weight: 800;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: 6px 0;
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--gradient-brand);
  transition: width var(--transition-fast);
  border-radius: 2px;
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-icon {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid var(--border-subtle);
  background: var(--bg-glass);
  color: var(--text-secondary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-icon:hover {
  color: var(--text-primary);
  background: var(--bg-glass-active);
  border-color: var(--border-card);
  transform: translateY(-1px);
}

.nav-toggle {
  display: none;
}

/* Hero Section */
.hero-section {
  padding-top: 140px;
  padding-bottom: 70px;
  min-height: 85vh;
  display: flex;
  align-items: center;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 50px;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.25);
  border-radius: var(--radius-full);
  color: var(--accent-emerald);
  font-size: 0.85rem;
  font-weight: 500;
  width: fit-content;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent-emerald);
  box-shadow: 0 0 10px var(--accent-emerald);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { transform: scale(1.1); box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.hero-title {
  font-size: 3.5rem;
  line-height: 1.1;
  font-weight: 800;
}

.hero-subtitle {
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--accent-cyan);
  margin-top: -8px;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 580px;
}

.hero-tech-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

.tech-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.tech-badge:hover {
  color: var(--text-primary);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(56, 189, 248, 0.15);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: 8px;
}

/* Button System */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  font-size: 0.98rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  font-family: var(--font-body);
}

.btn-primary {
  background: var(--gradient-brand);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 25px rgba(56, 189, 248, 0.5);
  color: #ffffff;
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-card);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
}

.btn-ghost:hover {
  color: var(--text-primary);
  background: var(--bg-glass-active);
  border-color: var(--border-card);
  transform: translateY(-2px);
}

/* Hero Visual / Interactive Hub */
.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
}

.profile-card {
  width: 100%;
  max-width: 420px;
  background: var(--bg-card);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  position: relative;
  overflow: hidden;
  transition: transform var(--transition-normal);
}

.profile-card:hover {
  transform: translateY(-4px);
}

.profile-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-brand);
}

.profile-header {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-bottom: 24px;
}

.avatar-container {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 2px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 25px rgba(56, 189, 248, 0.35);
  position: relative;
}

.avatar-letters {
  font-size: 2.2rem;
  font-weight: 800;
  font-family: var(--font-heading);
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.profile-meta h3 {
  font-size: 1.35rem;
  margin-bottom: 4px;
}

.profile-meta p {
  color: var(--accent-cyan);
  font-size: 0.9rem;
  font-weight: 500;
}

.profile-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px 12px;
  margin-bottom: 24px;
  text-align: center;
}

.stat-item .stat-num {
  font-size: 1.45rem;
  font-weight: 800;
  font-family: var(--font-heading);
  color: var(--text-primary);
}

.stat-item .stat-lbl {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  margin-top: 2px;
}

.hero-quick-terminal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.terminal-header {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 10px;
}

.dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
}
.dot-red { background: #ef4444; }
.dot-yellow { background: #f59e0b; }
.dot-green { background: #10b981; }

.terminal-line {
  line-height: 1.7;
}

.terminal-prompt {
  color: var(--accent-cyan);
}

.terminal-highlight {
  color: #f1f5f9;
  font-weight: 600;
}

/* Section Header Structure */
.section {
  padding: 80px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 50px auto;
}

.section-tag {
  display: inline-block;
  padding: 4px 12px;
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.25);
  border-radius: var(--radius-full);
  color: var(--accent-indigo);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.4rem;
  margin-bottom: 16px;
  line-height: 1.2;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   Interactive Lab & Telemetry Featurette
   ========================================================================== */
.lab-box {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.lab-tabs-nav {
  display: flex;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-subtle);
  overflow-x: auto;
  scrollbar-width: none;
}

.lab-tabs-nav::-webkit-scrollbar {
  display: none;
}

.lab-tab-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 28px;
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.lab-tab-btn:hover {
  color: var(--text-primary);
  background: var(--bg-glass);
}

.lab-tab-btn.active {
  color: var(--accent-cyan);
  border-bottom-color: var(--accent-cyan);
  background: var(--bg-card);
}

.tab-pane {
  display: none;
  padding: 36px;
  animation: fadeIn 0.3s ease;
}

.tab-pane.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Weather Station Telemetry Pane */
.telemetry-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.telemetry-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.telemetry-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-cyan);
}

.telemetry-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.telemetry-title {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

.telemetry-icon {
  font-size: 1.25rem;
  color: var(--accent-cyan);
}

.telemetry-value {
  font-size: 2.2rem;
  font-weight: 800;
  font-family: var(--font-heading);
  color: var(--text-primary);
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.telemetry-unit {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
}

.telemetry-sub {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 6px;
}

.telemetry-console-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 20px;
  font-size: 0.9rem;
}

.status-badge-inline {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  color: var(--accent-emerald);
}

.telemetry-controls {
  display: flex;
  gap: 12px;
}

/* Ohio HS Football / Harbin Calculator Pane */
.harbin-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: center;
}

.harbin-info h4 {
  font-size: 1.4rem;
  margin-bottom: 10px;
}

.harbin-info p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.7;
}

.harbin-formula-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  margin-bottom: 20px;
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 20px;
}

.calc-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.calc-group input, .calc-group select {
  width: 100%;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.95rem;
  outline: none;
  transition: border-color var(--transition-fast);
}

.calc-group input:focus, .calc-group select:focus {
  border-color: var(--accent-cyan);
}

.harbin-result-card {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.08) 0%, rgba(99, 102, 241, 0.08) 100%);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
}

.harbin-result-score {
  font-size: 2.8rem;
  font-weight: 800;
  font-family: var(--font-heading);
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin: 6px 0;
}

/* IoT & Embedded Packet Stream Pane */
.packet-stream-box {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 28px;
}

.packet-log {
  background: #020617;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 18px;
  height: 280px;
  overflow-y: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.6;
}

.packet-row {
  display: flex;
  gap: 12px;
  margin-bottom: 6px;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.05);
  padding-bottom: 4px;
}

.pkt-time { color: var(--text-muted); }
.pkt-src { color: var(--accent-cyan); font-weight: 600; }
.pkt-data { color: #e2e8f0; }

.hardware-spec-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.spec-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.spec-icon {
  font-size: 1.8rem;
  color: var(--accent-indigo);
}

.spec-card h5 {
  font-size: 1rem;
  margin-bottom: 2px;
}

.spec-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   Projects Section
   ========================================================================== */
.project-filters {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 40px;
}

.filter-btn {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

.filter-btn.active {
  background: var(--text-primary);
  color: var(--bg-primary);
  border-color: var(--text-primary);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 28px;
}

.project-card {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.project-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg), 0 0 25px rgba(56, 189, 248, 0.15);
  border-color: var(--border-glow);
}

.project-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 18px;
}

.project-icon-badge {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--accent-cyan);
}

.project-stars-pill {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 4px 10px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-amber);
}

.project-card h3 {
  font-size: 1.35rem;
  margin-bottom: 10px;
  line-height: 1.3;
}

.project-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.project-tag {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  padding: 3px 9px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
}

.project-links {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 18px;
}

.project-link-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

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

/* ==========================================================================
   Skill & Architecture Matrix
   ========================================================================== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.skill-category-card {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.skill-category-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-cyan);
}

.skill-category-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
}

.skill-cat-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: var(--accent-cyan);
}

.skill-category-header h3 {
  font-size: 1.15rem;
}

.skill-items-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.skill-item-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.9rem;
}

.skill-item-name {
  color: var(--text-secondary);
  font-weight: 500;
}

.skill-item-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background: var(--bg-glass-active);
  color: var(--accent-cyan);
}

/* ==========================================================================
   About Me Section
   ========================================================================== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.about-content {
  display: flex;
  flex-direction: column;
  gap: 18px;
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.about-highlights {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 10px;
}

.highlight-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 18px;
}

.highlight-box h4 {
  font-size: 1.05rem;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.highlight-box p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.about-quote-box {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 36px;
  position: relative;
  box-shadow: var(--shadow-lg);
}

.about-quote-box::before {
  content: '"';
  position: absolute;
  top: 10px;
  left: 20px;
  font-size: 6rem;
  line-height: 1;
  color: var(--border-subtle);
  font-family: serif;
  pointer-events: none;
}

.quote-text {
  font-size: 1.25rem;
  font-weight: 500;
  line-height: 1.6;
  color: var(--text-primary);
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
}

.quote-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-info h5 {
  font-size: 1rem;
}

.author-info p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Contact Section
   ========================================================================== */
.contact-card-wrapper {
  background: var(--bg-card);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  position: relative;
  overflow: hidden;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.contact-info h3 {
  font-size: 2rem;
  line-height: 1.2;
}

.contact-info p {
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.7;
}

.contact-channels {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.channel-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 18px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.channel-item:hover {
  border-color: var(--accent-cyan);
  transform: translateX(4px);
}

.channel-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  background: var(--bg-glass);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: var(--accent-cyan);
}

.channel-details h5 {
  font-size: 0.9rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.channel-details a, .channel-details span {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

/* Quick Interactive Message Form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.form-group label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.15);
}

textarea.form-control {
  resize: vertical;
  min-height: 110px;
}

/* Toast Notification */
.toast-notice {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--bg-secondary);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-full);
  padding: 12px 24px;
  display: flex;
  align-items: center;
  gap: 10px;
  box-shadow: var(--shadow-lg), 0 0 20px rgba(56, 189, 248, 0.3);
  z-index: 1000;
  transform: translateY(100px);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.toast-notice.show {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: 40px 0 50px 0;
  background: var(--bg-secondary);
  margin-top: 60px;
}

.footer-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-copy {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-domain-badge {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 4px 10px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--accent-cyan);
}

/* Back to Top Floating Button */
.back-to-top {
  position: fixed;
  bottom: 24px;
  left: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 90;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-md);
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-cyan);
  transform: translateY(-3px);
}

/* ==========================================================================
   Responsive Media Queries
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-visual {
    order: -1;
  }

  .profile-card {
    max-width: 100%;
  }

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

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

  .harbin-container {
    grid-template-columns: 1fr;
  }

  .packet-stream-box {
    grid-template-columns: 1fr;
  }

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

  .contact-card-wrapper {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.6rem;
  }

  .hero-subtitle {
    font-size: 1.15rem;
  }

  .section-title {
    font-size: 2rem;
  }

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

  .nav-links {
    display: none;
  }

  .nav-links.mobile-open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 65px;
    left: 0;
    right: 0;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow-lg);
    gap: 16px;
  }

  .nav-toggle {
    display: inline-flex;
  }

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

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

  .footer-container {
    flex-direction: column;
    text-align: center;
  }
}