/* ==========================================================================
   Luc Nguyen (Lucnn) - Personal Brand & Portfolio Stylesheet
   Design Philosophy: Apple Design & Fluid Interfaces (WWDC Principles for Web)
   Crafted with: Translucent Materials, Specular Light Highlights,
                 Optical Typography & Squircle Geometries.
   ========================================================================== */

:root {
  /* Apple System Typography Stack */
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Inter", "Helvetica Neue", system-ui, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", Menlo, Monaco, Consolas, monospace;

  /* Color Palette - Dark Core (macOS Tahoe & Deep Space Gray) */
  --bg-primary: #08090d;
  --bg-secondary: #0e1017;
  --bg-card: rgba(22, 26, 38, 0.6);
  --bg-card-hover: rgba(28, 34, 50, 0.78);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-subtle: rgba(255, 255, 255, 0.05);
  --border-hover: rgba(255, 255, 255, 0.2);

  /* Apple Translucent Materials (Glassmorphism & Depth) */
  --glass-bg: rgba(22, 26, 38, 0.62);
  --glass-bg-hover: rgba(30, 36, 52, 0.78);
  --glass-bg-subtle: rgba(16, 19, 28, 0.5);
  --glass-border: rgba(255, 255, 255, 0.1);
  --glass-border-subtle: rgba(255, 255, 255, 0.06);
  --glass-border-hover: rgba(255, 255, 255, 0.24);
  --glass-blur: blur(24px) saturate(190%);
  --glass-blur-sm: blur(14px) saturate(180%);

  /* Apple Layered Shadows with Specular Top Highlight */
  --glass-shadow-sm: 0 1px 0 0 rgba(255, 255, 255, 0.12) inset, 0 4px 16px 0 rgba(0, 0, 0, 0.25);
  --glass-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.14) inset, 0 10px 32px -4px rgba(0, 0, 0, 0.42), 0 2px 8px -1px rgba(0, 0, 0, 0.25);
  --glass-shadow-hover: 0 1px 0 0 rgba(255, 255, 255, 0.24) inset, 0 20px 48px -6px rgba(0, 0, 0, 0.58), 0 0 28px -4px rgba(10, 132, 255, 0.22);

  --text-primary: #f5f5f7;
  --text-secondary: #a1a1a6;
  --text-muted: #6e6e73;

  /* Apple System Accent Palette */
  --accent-cyan: #0a84ff;       /* Apple System Blue */
  --accent-blue: #0071e3;       /* Apple Pro Blue */
  --accent-purple: #bf5af2;     /* Apple System Purple */
  --accent-emerald: #30d158;    /* Apple System Green */
  --accent-amber: #ffd60a;      /* Apple System Yellow / Amber */
  --accent-rose: #ff453a;       /* Apple System Red */

  /* Apple Squircle Geometries */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  /* Apple Spring Curves (Critically Damped Default: Damping 1.0, Response 0.35s) */
  --spring-default: cubic-bezier(0.16, 1, 0.3, 1);
  --spring-snappy: cubic-bezier(0.2, 0.9, 0.2, 1);
  --spring-bounce: cubic-bezier(0.34, 1.4, 0.64, 1);
  --transition-fast: 0.12s var(--spring-default);
  --transition-normal: 0.28s var(--spring-default);
  --transition-spring: 0.45s var(--spring-default);

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-card: var(--glass-shadow);
  --shadow-hover: var(--glass-shadow-hover);
}

/* Light Theme Variables (macOS Light Appearance & Clean Crystal) */
body.light-theme {
  --bg-primary: #f5f5f7;
  --bg-secondary: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.76);
  --bg-card-hover: rgba(255, 255, 255, 0.92);
  --border-color: rgba(0, 0, 0, 0.08);
  --border-subtle: rgba(0, 0, 0, 0.04);
  --border-hover: rgba(0, 0, 0, 0.18);

  /* Light Translucent Materials */
  --glass-bg: rgba(255, 255, 255, 0.74);
  --glass-bg-hover: rgba(255, 255, 255, 0.92);
  --glass-bg-subtle: rgba(245, 245, 247, 0.65);
  --glass-border: rgba(255, 255, 255, 0.8);
  --glass-border-subtle: rgba(0, 0, 0, 0.06);
  --glass-border-hover: rgba(0, 113, 227, 0.35);

  --glass-shadow-sm: 0 1px 0 0 rgba(255, 255, 255, 0.9) inset, 0 2px 8px 0 rgba(0, 0, 0, 0.04);
  --glass-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.9) inset, 0 12px 32px -4px rgba(0, 0, 0, 0.08), 0 2px 6px -1px rgba(0, 0, 0, 0.04);
  --glass-shadow-hover: 0 1px 0 0 rgba(255, 255, 255, 1) inset, 0 20px 44px -4px rgba(0, 0, 0, 0.12), 0 0 24px -2px rgba(0, 113, 227, 0.16);

  --text-primary: #1d1d1f;
  --text-secondary: #515154;
  --text-muted: #86868b;

  --accent-cyan: #0071e3;
  --accent-blue: #0077ed;

  --shadow-card: var(--glass-shadow);
  --shadow-hover: var(--glass-shadow-hover);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.55;
  overflow-x: hidden;
  transition: background-color var(--transition-normal), color var(--transition-normal);
  position: relative;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Apple Smooth Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
  border: 2px solid transparent;
  background-clip: content-box;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.3);
  background-clip: content-box;
}
body.light-theme ::-webkit-scrollbar-thumb {
  background: rgba(0, 0, 0, 0.18);
  background-clip: content-box;
}
body.light-theme ::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 0, 0, 0.32);
  background-clip: content-box;
}

/* Tactile Response — Kill Latency on Pointer-Down (WWDC Fluid Interfaces Rule #1) */
button,
a,
input,
select,
textarea {
  -webkit-tap-highlight-color: transparent;
}

.btn-primary:active,
.btn-secondary:active,
.btn-control:active,
.filter-btn:active,
.floating-zalo-btn:active,
.contact-channel-item:active {
  transform: scale(0.972);
  transition: transform 90ms ease-out !important;
}

/* Ambient Spheres (Subtle Depth Atmosphere) */
.tech-bg {
  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);
  pointer-events: none;
  will-change: transform;
}

.orb-1 {
  top: -120px;
  left: 15%;
  width: 580px;
  height: 580px;
  background: radial-gradient(circle, rgba(10, 132, 255, 0.16) 0%, rgba(0, 113, 227, 0.05) 60%, transparent 100%);
  animation: orbDrift1 26s var(--spring-default) infinite alternate;
}
.orb-2 {
  top: 25%;
  right: -100px;
  width: 520px;
  height: 520px;
  background: radial-gradient(circle, rgba(191, 90, 242, 0.12) 0%, rgba(10, 132, 255, 0.04) 65%, transparent 100%);
  animation: orbDrift2 32s var(--spring-default) infinite alternate;
}
.orb-3 {
  bottom: 12%;
  left: -80px;
  width: 540px;
  height: 540px;
  background: radial-gradient(circle, rgba(48, 209, 88, 0.09) 0%, rgba(10, 132, 255, 0.04) 65%, transparent 100%);
  animation: orbDrift3 28s var(--spring-default) infinite alternate;
}
.orb-4 {
  top: 60%;
  right: 18%;
  width: 480px;
  height: 480px;
  background: radial-gradient(circle, rgba(0, 113, 227, 0.11) 0%, rgba(191, 90, 242, 0.04) 65%, transparent 100%);
  animation: orbDrift4 34s var(--spring-default) infinite alternate;
}

@keyframes orbDrift1 {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(40px, 30px) scale(1.06); }
}
@keyframes orbDrift2 {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-35px, 25px) scale(0.95); }
}
@keyframes orbDrift3 {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(30px, -20px) scale(1.04); }
}
@keyframes orbDrift4 {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-25px, 20px) scale(0.96); }
}

body.light-theme .ambient-orb {
  opacity: 0.35;
  filter: blur(100px);
}
body.light-theme .orb-1 {
  background: radial-gradient(circle, rgba(0, 113, 227, 0.18) 0%, rgba(10, 132, 255, 0.06) 60%, transparent 100%);
}
body.light-theme .orb-2 {
  background: radial-gradient(circle, rgba(191, 90, 242, 0.12) 0%, rgba(0, 113, 227, 0.05) 65%, transparent 100%);
}
body.light-theme .orb-3 {
  background: radial-gradient(circle, rgba(48, 209, 88, 0.12) 0%, rgba(0, 113, 227, 0.05) 65%, transparent 100%);
}
body.light-theme .orb-4 {
  background: radial-gradient(circle, rgba(0, 113, 227, 0.14) 0%, rgba(191, 90, 242, 0.05) 65%, transparent 100%);
}

/* Glassmorphism Reusable Classes */
.glassmorphism,
.glass-panel {
  background: var(--glass-bg) !important;
  backdrop-filter: var(--glass-blur) !important;
  -webkit-backdrop-filter: var(--glass-blur) !important;
  border: 1px solid var(--glass-border) !important;
  box-shadow: var(--glass-shadow) !important;
  border-radius: var(--radius-lg);
}
.glassmorphism:hover,
.glass-panel:hover {
  background: var(--glass-bg-hover) !important;
  border-color: var(--glass-border-hover) !important;
  box-shadow: var(--glass-shadow-hover) !important;
}

/* Container */
.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 1.5rem;
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   Navigation Bar (macOS Floating Chrome Layer)
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: 100;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.08) inset, 0 8px 24px -2px rgba(0, 0, 0, 0.28);
  transition: all var(--transition-normal);
}
body.light-theme .navbar {
  background: var(--glass-bg);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.9) inset, 0 8px 24px -2px rgba(0, 0, 0, 0.05);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
  transition: opacity var(--transition-fast);
}
.nav-brand:hover {
  opacity: 0.88;
}

.brand-avatar {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  overflow: hidden;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}
.brand-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.brand-text {
  display: flex;
  flex-direction: column;
}
.brand-name {
  font-weight: 700;
  font-size: 0.98rem;
  letter-spacing: -0.02em;
}
.brand-title {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  list-style: none;
}
.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  transition: color var(--transition-fast), transform var(--transition-fast);
  padding: 6px 4px;
}
.nav-link:hover {
  color: var(--text-primary);
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.btn-control {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  border: 1px solid var(--glass-border);
  color: var(--text-secondary);
  padding: 6px 13px;
  font-size: 0.84rem;
  font-weight: 500;
  border-radius: var(--radius-full);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-fast);
  text-decoration: none;
  box-shadow: var(--glass-shadow-sm);
}
.btn-control:hover {
  background: var(--glass-bg-hover);
  color: var(--text-primary);
  border-color: var(--glass-border-hover);
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--text-primary);
  color: var(--bg-primary);
  border: 1px solid var(--text-primary);
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}
.btn-primary:hover {
  opacity: 0.92;
  transform: translateY(-1.5px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.35);
}
body.light-theme .btn-primary {
  background: #1d1d1f;
  color: #ffffff;
  border-color: #1d1d1f;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.12);
}

.btn-secondary {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  color: var(--text-primary);
  border: 1px solid var(--glass-border);
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--glass-shadow-sm);
}
.btn-secondary:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-hover);
  transform: translateY(-1.5px);
  box-shadow: var(--glass-shadow);
}

.btn-zalo {
  border-color: rgba(0, 104, 255, 0.25);
  color: var(--text-primary);
}
.btn-zalo:hover {
  background: rgba(0, 104, 255, 0.12);
  border-color: #0068ff;
  color: #0068ff;
  box-shadow: 0 0 16px -2px rgba(0, 104, 255, 0.35);
}

.mobile-toggle {
  display: none;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-size: 1.4rem;
  cursor: pointer;
}

/* ==========================================================================
   Hero Section (Apple Optical Typography & Keynote Stature)
   ========================================================================== */
.hero-section {
  padding: 5.5rem 0 4.5rem;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 3.5rem;
  align-items: center;
}

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

.hero-badge-wrap {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  border: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  box-shadow: var(--glass-shadow-sm);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  letter-spacing: -0.01em;
  margin-bottom: 1.5rem;
  width: fit-content;
}

.status-dot-green {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
}

.hero-title {
  font-size: 2.85rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.035em;
  margin-bottom: 0.85rem;
  color: var(--text-primary);
}

.hero-title .highlight-name {
  color: var(--text-primary);
  background: linear-gradient(180deg, #ffffff 30%, #a1a1a6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
body.light-theme .hero-title .highlight-name {
  background: linear-gradient(180deg, #1d1d1f 30%, #515154 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--accent-cyan);
  margin-bottom: 1.25rem;
  letter-spacing: -0.015em;
}

.hero-desc {
  font-size: 1.04rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 2.25rem;
  max-width: 580px;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-bottom: 2.75rem;
}

.hero-stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.hero-stat-card {
  display: flex;
  flex-direction: column;
}

.hero-stat-val {
  font-size: 1.95rem;
  font-weight: 800;
  color: var(--text-primary);
  font-family: var(--font-mono);
  letter-spacing: -0.04em;
  line-height: 1.05;
}
.stat-plus {
  color: var(--accent-cyan);
  font-size: 1.25rem;
  font-weight: 700;
}

.hero-stat-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-top: 4px;
  letter-spacing: -0.01em;
}

/* Right Visual Profile Card (Apple Squircle Glass Card) */
.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
}

.profile-card {
  width: 100%;
  max-width: 410px;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 1.85rem;
  box-shadow: var(--glass-shadow);
  transition: all var(--transition-spring);
}
.profile-card:hover {
  transform: translateY(-3px);
  border-color: var(--glass-border-hover);
  box-shadow: var(--glass-shadow-hover);
}

.card-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--glass-border);
}

.terminal-dots {
  display: flex;
  align-items: center;
  gap: 7px;
}
.terminal-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.dot-red { background: #ff5f56; border: 1px solid rgba(0, 0, 0, 0.12); }
.dot-yellow { background: #ffbd2e; border: 1px solid rgba(0, 0, 0, 0.12); }
.dot-green { background: #27c93f; border: 1px solid rgba(0, 0, 0, 0.12); }

.status-indicator {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  color: var(--accent-emerald);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.profile-avatar-box {
  width: 92px;
  height: 92px;
  margin: 0 auto 1.25rem;
  border-radius: var(--radius-full);
  overflow: hidden;
  border: 2px solid var(--glass-border);
  background: var(--bg-secondary);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}
.profile-avatar-box img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.profile-card-info {
  text-align: center;
  margin-bottom: 1.25rem;
}
.profile-card-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin-bottom: 3px;
}
.profile-card-role {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.profile-tech-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
  margin-bottom: 1.35rem;
}
.tech-pill {
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: var(--glass-bg-subtle);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  color: var(--text-secondary);
  border: 1px solid var(--glass-border-subtle);
  font-family: var(--font-mono);
  font-weight: 500;
  transition: all var(--transition-fast);
}
.tech-pill:hover {
  color: var(--text-primary);
  border-color: var(--glass-border);
  transform: translateY(-1px);
}

.profile-card-terminal-snippet {
  background: rgba(8, 10, 15, 0.7);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.6;
}
body.light-theme .profile-card-terminal-snippet {
  background: rgba(240, 240, 243, 0.8);
}
.code-cyan { color: var(--accent-cyan); font-weight: 600; }
.code-green { color: var(--accent-emerald); }
.code-blue { color: #60a5fa; }

/* ==========================================================================
   Common Section Headers (Apple Keynote Clarity)
   ========================================================================== */
.section {
  padding: 5.5rem 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 3.5rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.6rem;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  margin-bottom: 0.85rem;
  line-height: 1.2;
}

.section-subtitle {
  font-size: 1.02rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==========================================================================
   About Me Section
   ========================================================================== */
.about-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 3.25rem;
  align-items: start;
}

.about-text .lead-text {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
  line-height: 1.6;
  letter-spacing: -0.015em;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 1.1rem;
  font-size: 0.98rem;
  line-height: 1.7;
}

.about-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-top: 2rem;
}

.about-feat-item {
  display: flex;
  gap: 13px;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  border: 1px solid var(--glass-border);
  padding: 1.2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--glass-shadow-sm);
  transition: all var(--transition-normal);
}
.about-feat-item:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-hover);
  transform: translateY(-2px);
  box-shadow: var(--glass-shadow);
}

.feat-icon-box {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  flex-shrink: 0;
}
.feat-icon-box svg {
  width: 20px;
  height: 20px;
}

.feat-info h4 {
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}
.feat-info p {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 0;
}

.about-card-stack {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.value-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 1.6rem;
  box-shadow: var(--glass-shadow-sm);
  transition: all var(--transition-normal);
}
.value-card:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-hover);
  transform: translateY(-2px);
  box-shadow: var(--glass-shadow);
}

.value-card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 0.75rem;
}
.value-number {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent-cyan);
  padding: 4px 9px;
  border-radius: var(--radius-sm);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border);
}
.value-card h3 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.015em;
}
.value-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==========================================================================
   Ecosystem & Projects Section (Apple Segmented Control & Squircle Cards)
   ========================================================================== */
.filter-tabs {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 4px;
  margin: 0 auto 3rem;
  padding: 5px;
  background: var(--glass-bg-subtle);
  backdrop-filter: var(--glass-blur-sm);
  -webkit-backdrop-filter: var(--glass-blur-sm);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-full);
  box-shadow: var(--glass-shadow-sm);
}

.filter-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 8px 18px;
  font-size: 0.86rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-normal);
}
.filter-btn:hover {
  color: var(--text-primary);
}
.filter-btn.active {
  background: var(--text-primary);
  color: var(--bg-primary);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.28);
}
body.light-theme .filter-btn.active {
  background: #1d1d1f;
  color: #ffffff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.12);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
}

.project-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 1.7rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-spring);
  box-shadow: var(--glass-shadow);
  position: relative;
  overflow: hidden;
}
.project-card:hover {
  border-color: var(--glass-border-hover);
  background: var(--glass-bg-hover);
  transform: translateY(-4px);
  box-shadow: var(--glass-shadow-hover);
}

.project-badge-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.1rem;
}

.project-cat-tag {
  font-size: 0.74rem;
  font-weight: 600;
  color: var(--accent-cyan);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border-subtle);
  padding: 3px 9px;
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.project-status-tag {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.project-status-tag.status-live {
  color: var(--accent-emerald);
}

.project-icon-title {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 0.95rem;
}

.project-icon-box {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}
.project-icon-box img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.project-icon-box svg {
  width: 22px;
  height: 22px;
  color: var(--text-primary);
}

.project-title {
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.project-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.2rem;
  flex-grow: 1;
}

.project-features-list {
  list-style: none;
  margin-bottom: 1.35rem;
  display: flex;
  flex-direction: column;
  gap: 7px;
}
.project-features-list li {
  font-size: 0.82rem;
  color: var(--text-muted);
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.45;
}
.project-features-list li::before {
  content: "—";
  color: var(--accent-cyan);
  font-weight: 700;
}

.project-tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 1.35rem;
}
.tech-tag {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  background: var(--glass-bg-subtle);
  color: var(--text-muted);
  border: 1px solid var(--glass-border-subtle);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
}

.project-actions {
  margin-top: auto;
}
.btn-card {
  width: 100%;
  justify-content: center;
  font-size: 0.85rem;
  padding: 9px 16px;
}

/* ==========================================================================
   Services Section
   ========================================================================== */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
}

.service-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 1.85rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-spring);
  box-shadow: var(--glass-shadow);
}
.service-card:hover {
  border-color: var(--glass-border-hover);
  background: var(--glass-bg-hover);
  transform: translateY(-4px);
  box-shadow: var(--glass-shadow-hover);
}

.service-icon-wrap {
  width: 46px;
  height: 46px;
  border-radius: var(--radius-lg);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  margin-bottom: 1.35rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}
.service-icon-wrap svg {
  width: 24px;
  height: 24px;
}

.service-card h3 {
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.8rem;
  letter-spacing: -0.02em;
  line-height: 1.35;
}

.service-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.35rem;
}

.service-benefits {
  list-style: none;
  margin-bottom: 1.85rem;
  display: flex;
  flex-direction: column;
  gap: 9px;
  flex-grow: 1;
}
.service-benefits li {
  font-size: 0.85rem;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.45;
}
.service-benefits li svg {
  color: var(--accent-emerald);
  flex-shrink: 0;
  margin-top: 2px;
}

.service-footer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1.35rem;
  border-top: 1px solid var(--glass-border);
  margin-top: auto;
}

.service-badge {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
}

/* ==========================================================================
   Tech Stack & Skills Section
   ========================================================================== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.6rem;
}

.skill-category-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 1.7rem;
  box-shadow: var(--glass-shadow);
  transition: all var(--transition-spring);
}
.skill-category-card:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-hover);
  transform: translateY(-3px);
  box-shadow: var(--glass-shadow-hover);
}

.skill-cat-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1.35rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--glass-border);
  letter-spacing: -0.015em;
}
.skill-cat-title svg {
  color: var(--accent-cyan);
}

.skill-items-list {
  display: flex;
  flex-direction: column;
  gap: 1.05rem;
}

.skill-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.skill-name-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.84rem;
}
.skill-name {
  color: var(--text-secondary);
  font-weight: 500;
}
.skill-level {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.skill-progress-bar {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
}
body.light-theme .skill-progress-bar {
  background: rgba(0, 0, 0, 0.08);
}
.skill-progress-fill {
  height: 100%;
  background: var(--accent-cyan);
  border-radius: var(--radius-full);
}

/* ==========================================================================
   Contact Section
   ========================================================================== */
.contact-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 2.75rem;
}

.contact-info-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 2.2rem;
  display: flex;
  flex-direction: column;
  box-shadow: var(--glass-shadow);
}
.contact-info-card h3 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}
.contact-info-card p {
  color: var(--text-secondary);
  font-size: 0.94rem;
  line-height: 1.6;
  margin-bottom: 2rem;
}

.contact-channels {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-channel-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 13px 18px;
  border-radius: var(--radius-lg);
  background: var(--glass-bg-subtle);
  border: 1px solid var(--glass-border);
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-normal);
  box-shadow: var(--glass-shadow-sm);
}
.contact-channel-item:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-hover);
  transform: translateX(3px);
  box-shadow: var(--glass-shadow);
}

.contact-channel-item.channel-zalo:hover {
  border-color: rgba(0, 104, 255, 0.45);
  box-shadow: 0 4px 20px -2px rgba(0, 104, 255, 0.25);
}

.channel-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  flex-shrink: 0;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}
.channel-icon svg {
  width: 22px;
  height: 22px;
}

.channel-icon-zalo {
  background: #0068ff;
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.25);
}
.channel-icon-zalo svg {
  fill: #ffffff;
}

.channel-meta {
  display: flex;
  flex-direction: column;
}
.channel-label {
  font-size: 0.76rem;
  color: var(--text-muted);
  font-weight: 500;
}
.channel-val {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-primary);
  font-family: var(--font-mono);
}

.contact-form-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 2.2rem;
  box-shadow: var(--glass-shadow);
}
.contact-form-card h3 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

.form-status-alert {
  display: none;
  padding: 13px 18px;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  margin-bottom: 1.5rem;
  line-height: 1.5;
}
.form-status-alert.success {
  display: block;
  background: rgba(48, 209, 88, 0.12);
  border: 1px solid rgba(48, 209, 88, 0.35);
  color: #34d399;
}
.form-status-alert.error {
  display: block;
  background: rgba(255, 69, 58, 0.12);
  border: 1px solid rgba(255, 69, 58, 0.35);
  color: #f87171;
}

.form-group-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.1rem;
  margin-bottom: 1.1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 7px;
  margin-bottom: 1.1rem;
}

.form-label {
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-secondary);
  letter-spacing: -0.01em;
}

.form-input, .form-select, .form-textarea {
  background: rgba(8, 10, 15, 0.6);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  padding: 11px 15px;
  font-size: 0.9rem;
  border-radius: var(--radius-md);
  font-family: inherit;
  transition: all var(--transition-fast);
}
body.light-theme .form-input,
body.light-theme .form-select,
body.light-theme .form-textarea {
  background: rgba(255, 255, 255, 0.8);
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(10, 132, 255, 0.18);
}
.form-textarea {
  min-height: 115px;
  resize: vertical;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  border-top: 1px solid var(--border-color);
  padding: 4.5rem 0 2.5rem;
  background: var(--bg-secondary);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 2.75rem;
  margin-bottom: 3.5rem;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.88rem;
  line-height: 1.6;
  margin-top: 1rem;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1.1rem;
  letter-spacing: -0.01em;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 9px;
}
.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color var(--transition-fast);
}
.footer-links a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Floating Quick Contact Widget (Zalo - Apple Floating Island Style)
   ========================================================================== */
.floating-contact {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 999;
}

.floating-zalo-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 18px 10px 12px;
  background: rgba(0, 104, 255, 0.92);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: var(--radius-full);
  color: #ffffff !important;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.88rem;
  box-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.4) inset, 0 12px 32px -4px rgba(0, 104, 255, 0.45);
  transition: all var(--transition-normal);
  position: relative;
}
.floating-zalo-btn:hover {
  background: #0068ff;
  transform: translateY(-2px);
  box-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.5) inset, 0 18px 40px -4px rgba(0, 104, 255, 0.55);
}

.floating-zalo-icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}
.floating-zalo-icon svg {
  fill: #0068ff;
}

.floating-zalo-pulse {
  position: absolute;
  top: -4px;
  left: -4px;
  right: -4px;
  bottom: -4px;
  border-radius: var(--radius-full);
  border: 2px solid rgba(0, 104, 255, 0.6);
  pointer-events: none;
  animation: zaloPulse 2.4s var(--spring-default) infinite;
}

@keyframes zaloPulse {
  0% { transform: scale(0.96); opacity: 0.8; }
  50% { transform: scale(1.08); opacity: 0; }
  100% { transform: scale(1.08); opacity: 0; }
}

/* ==========================================================================
   Apple Accessibility & Media Queries (WWDC Principle #14)
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .ambient-orb {
    animation: none !important;
    transform: none !important;
  }
  .floating-zalo-pulse {
    animation: none !important;
    display: none !important;
  }
  .project-card:hover,
  .service-card:hover,
  .value-card:hover,
  .about-feat-item:hover,
  .profile-card:hover {
    transform: none !important;
  }
}

@media (prefers-reduced-transparency: reduce) {
  .glassmorphism,
  .glass-panel,
  .navbar,
  .profile-card,
  .project-card,
  .service-card,
  .skill-category-card,
  .contact-info-card,
  .contact-form-card,
  .about-feat-item,
  .value-card,
  .floating-zalo-btn {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
    background: var(--bg-secondary) !important;
  }
}

@media (prefers-contrast: more) {
  :root {
    --glass-border: rgba(255, 255, 255, 0.35);
    --border-color: rgba(255, 255, 255, 0.35);
  }
  body.light-theme {
    --glass-border: rgba(0, 0, 0, 0.35);
    --border-color: rgba(0, 0, 0, 0.35);
  }
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  .hero-visual {
    order: -1;
  }
  .projects-grid, .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .skills-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    width: 100%;
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--glass-border);
    flex-direction: column;
    padding: 1.5rem;
    gap: 1.25rem;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4);
  }
  .nav-links.active {
    display: flex;
  }
  .mobile-toggle {
    display: block;
  }
  .hero-title {
    font-size: 2.25rem;
  }
  .hero-stats-row {
    grid-template-columns: repeat(2, 1fr);
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .about-features {
    grid-template-columns: 1fr;
  }
  .projects-grid, .services-grid, .skills-grid {
    grid-template-columns: 1fr;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .form-group-row {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 0.75rem;
    text-align: center;
  }
  .floating-contact {
    bottom: 20px;
    right: 20px;
  }
}