/*
 * ===============================================================================
 * WORLD-CLASS RESUME WEBSITE - CSS STYLES
 * Author: Vu Tuan Chien - Enterprise Lean & Agile Coach
 * Version: 2.1.2 (Updated: 2025-10-29)
 * 
 * Built following modern web standards and best practices:
 * - Mobile-first responsive design (MDN/web.dev recommendations)
 * - CSS Grid and Flexbox for layouts
 * - Accessible design patterns
 * - Performance optimized
 * - Modern typography system
 * - Clean, semantic structure
 * ===============================================================================
 */

/* =============================================================================
   CSS CUSTOM PROPERTIES (DESIGN SYSTEM)
   ============================================================================= */

:root {
  /* Color Palette - Professional and Modern */
  --color-primary: #2563eb;         /* Blue - Professional, trustworthy */
  --color-primary-light: #3b82f6;   /* Light blue */
  --color-primary-dark: #1d4ed8;    /* Dark blue */
  --color-secondary: #10b981;       /* Green - Lean/Agile theme */
  --color-accent: #f59e0b;          /* Amber - Attention/CTA */
  
  /* Neutral Colors */
  --color-white: #ffffff;
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-gray-900: #111827;
  
  /* Semantic Colors */
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-info: var(--color-primary);
  
  /* Background Colors */
  --bg-primary: var(--color-white);
  --bg-secondary: var(--color-gray-50);
  --bg-tertiary: #f0f9ff;           /* Very light blue */
  --bg-dark: var(--color-gray-900);
  
  /* Typography Scale (Using perfect scale ratios) */
  --font-family-primary: 'Inter', system-ui, -apple-system, sans-serif;
  --font-family-mono: 'JetBrains Mono', 'SF Mono', Consolas, monospace;
  
  /* Fluid Typography using clamp() - Recommended by MDN */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);      /* 12-14px */
  --text-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);        /* 14-16px */
  --text-base: clamp(1rem, 0.9rem + 0.5vw, 1.125rem);        /* 16-18px */
  --text-lg: clamp(1.125rem, 1rem + 0.625vw, 1.25rem);       /* 18-20px */
  --text-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);        /* 20-24px */
  --text-2xl: clamp(1.5rem, 1.3rem + 1vw, 1.875rem);         /* 24-30px */
  --text-3xl: clamp(1.875rem, 1.6rem + 1.375vw, 2.25rem);    /* 30-36px */
  --text-4xl: clamp(2.25rem, 1.9rem + 1.75vw, 3rem);         /* 36-48px */
  --text-5xl: clamp(3rem, 2.5rem + 2.5vw, 4rem);             /* 48-64px */
  
  /* Font Weights */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Line Heights */
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.625;
  
  /* Spacing Scale (Using 8px base unit) */
  --space-xs: 0.25rem;    /* 4px */
  --space-sm: 0.5rem;     /* 8px */
  --space-md: 1rem;       /* 16px */
  --space-lg: 1.5rem;     /* 24px */
  --space-xl: 2rem;       /* 32px */
  --space-2xl: 3rem;      /* 48px */
  --space-3xl: 4rem;      /* 64px */
  --space-4xl: 6rem;      /* 96px */
  
  /* Container Widths */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;
  --container-2xl: 1536px;
  
  /* Border Radius */
  --radius-sm: 0.25rem;   /* 4px */
  --radius-md: 0.5rem;    /* 8px */
  --radius-lg: 0.75rem;   /* 12px */
  --radius-xl: 1rem;      /* 16px */
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;
  
  /* Z-index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal: 1040;
  --z-popover: 1050;
  --z-tooltip: 1060;
}

/* =============================================================================
   RESET AND BASE STYLES
   ============================================================================= */

/* Modern CSS Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 100%; /* Allow user zoom */
}

body {
  font-family: var(--font-family-primary);
  font-size: var(--text-base);
  line-height: var(--line-height-normal);
  color: var(--color-gray-700);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

/* Responsive Media - MDN recommendation */
img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

/* Remove button styling */
button {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
  background: transparent;
  border: 0;
  cursor: pointer;
}

/* Focus management for accessibility */
:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* Screen reader only content */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Skip link for accessibility */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--color-primary);
  color: white;
  padding: 8px;
  text-decoration: none;
  border-radius: var(--radius-md);
  z-index: var(--z-tooltip);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 6px;
}

/* =============================================================================
   LAYOUT COMPONENTS
   ============================================================================= */

/* Container - Mobile-first with max-width constraints */
.container {
  width: 100%;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-md);
  padding-right: var(--space-md);
}

/* Responsive breakpoints using min-width (mobile-first) */
@media (min-width: 640px) {
  .container {
    max-width: var(--container-sm);
    padding-left: var(--space-lg);
    padding-right: var(--space-lg);
  }
}

@media (min-width: 768px) {
  .container {
    max-width: var(--container-md);
  }
}

@media (min-width: 1024px) {
  .container {
    max-width: var(--container-lg);
    padding-left: var(--space-xl);
    padding-right: var(--space-xl);
  }
}

@media (min-width: 1280px) {
  .container {
    max-width: var(--container-xl);
  }
}

@media (min-width: 1536px) {
  .container {
    max-width: var(--container-2xl);
  }
}

/* =============================================================================
   HEADER AND NAVIGATION
   ============================================================================= */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-gray-200);
  z-index: var(--z-fixed);
  transition: all var(--transition-normal) cubic-bezier(0.4, 0, 0.2, 1);
}

.header-scrolled {
  background-color: rgba(255, 255, 255, 0.98);
  box-shadow: var(--shadow-lg);
}

.header-hidden {
  transform: translateY(-100%);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  max-width: var(--container-xl);
  margin: 0 auto;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  text-decoration: none;
}

.nav-avatar {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: 2px solid var(--color-primary-light);
}

.nav-name {
  font-size: var(--text-lg);
}

/* Mobile responsive for hero stats */
@media (max-width: 640px) {
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .hero-description {
    text-align: left;
  }
}

/* Mobile Navigation Toggle */
.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: var(--space-sm);
  background: none;
  border: none;
  cursor: pointer;
  z-index: var(--z-modal);
}

.nav-toggle-line {
  width: 24px;
  height: 2px;
  background-color: var(--color-gray-700);
  transition: all var(--transition-fast);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* Navigation Menu */
.nav-menu {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(10px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
  list-style: none;
  transform: translateX(-100%);
  transition: transform var(--transition-normal);
  z-index: var(--z-fixed);
}

.nav-menu-open {
  transform: translateX(0);
}

.nav-link {
  display: block;
  font-size: var(--text-xl);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
  text-decoration: none;
  padding: var(--space-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover,
.nav-link:focus {
  color: var(--color-primary);
  background-color: var(--bg-tertiary);
}

.nav-link-primary {
  background-color: var(--color-primary);
  color: white;
}

.nav-link-primary:hover,
.nav-link-primary:focus {
  background-color: var(--color-primary-dark);
  color: white;
}

/* Desktop Navigation */
@media (min-width: 768px) {
  .nav-toggle {
    display: none;
  }
  
  .nav-menu {
    position: static;
    background: none;
    backdrop-filter: none;
    flex-direction: row;
    gap: var(--space-lg);
    transform: none;
  }
  
  .nav-link {
    font-size: var(--text-base);
    padding: var(--space-sm) var(--space-md);
  }
}

/* =============================================================================
   BUTTONS AND INTERACTIVE ELEMENTS
   ============================================================================= */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-lg);
  font-weight: var(--font-weight-medium);
  text-decoration: none;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.btn-primary:hover,
.btn-primary:focus {
  background-color: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.btn-secondary:hover,
.btn-secondary:focus {
  background-color: var(--color-primary);
  color: white;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-gray-700);
  border-color: var(--color-gray-300);
}

.btn-outline:hover,
.btn-outline:focus {
  background-color: var(--color-gray-50);
  color: var(--color-gray-900);
  border-color: var(--color-gray-400);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.btn-full {
  width: 100%;
  justify-content: center;
}

/* =============================================================================
   HERO SECTION
   ============================================================================= */

.hero {
  padding: calc(80px + var(--space-4xl)) 0 var(--space-4xl);
  background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-primary) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 25% 25%, rgba(37, 99, 235, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 75% 75%, rgba(16, 185, 129, 0.1) 0%, transparent 50%);
  pointer-events: none;
}

.hero-content {
  display: grid;
  gap: var(--space-2xl);
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-text {
  text-align: center;
  max-width: 100%;
}

.hero-title {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
}

.hero-greeting {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-medium);
  color: var(--color-primary);
}

.hero-name {
  font-size: var(--text-5xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gray-900);
  line-height: var(--line-height-tight);
}

.hero-role {
  font-size: var(--text-2xl);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-600);
}

.hero-description {
  font-size: var(--text-lg);
  color: var(--color-gray-600);
  margin-bottom: var(--space-xl);
  max-width: 720px;
  margin-left: auto;
  margin-right: auto;
  text-align: justify;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  margin-bottom: var(--space-2xl);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  margin-top: var(--space-2xl);
}

.stat-item {
  text-align: center;
}

.stat-number {
  display: block;
  font-size: var(--text-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
}

.stat-label {
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  font-weight: var(--font-weight-medium);
}

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

.avatar-container {
  position: relative;
  display: inline-block;
}

.avatar {
  width: 280px;
  height: 280px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: 4px solid white;
  box-shadow: var(--shadow-xl);
}

.avatar-badge {
  position: absolute;
  bottom: 20px;
  right: 20px;
  width: 48px;
  height: 48px;
  background-color: var(--color-secondary);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--text-lg);
  border: 4px solid white;
  box-shadow: var(--shadow-md);
}

/* Desktop Hero Layout */
@media (min-width: 768px) {
  .hero-content {
    grid-template-columns: 1.2fr 400px;
    gap: var(--space-2xl);
    text-align: left;
  }
  
  .hero-text {
    text-align: left;
    max-width: 100%;
  }
  
  .hero-description {
    margin-left: 0;
    margin-right: 0;
    max-width: 100%;
  }
  
  .hero-actions {
    flex-direction: row;
  }
  
  .hero-stats {
    grid-template-columns: repeat(4, 1fr);
    text-align: left;
  }
  
  .avatar {
    width: 320px;
    height: 320px;
  }
}

/* =============================================================================
   SECTION COMPONENTS
   ============================================================================= */

section {
  padding: var(--space-4xl) 0;
}

section:nth-child(even) {
  background-color: var(--bg-secondary);
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.section-title {
  font-size: var(--text-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-md);
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--color-gray-600);
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
  line-height: 1.6;
  letter-spacing: -0.01em;
}

/* =============================================================================
   ABOUT SECTION
   ============================================================================= */

.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  margin: 0 auto var(--space-3xl);
  align-items: stretch;
  max-width: 860px;
}

.about-heading {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-md);
}

/* Feature Cards for Objective & Philosophy */
.about-feature-card {
  position: relative;
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.96), rgba(242, 249, 255, 0.9));
  padding: var(--space-2xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(37, 99, 235, 0.08);
  transition: all var(--transition-base);
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  height: 100%;
  overflow: hidden;
  backdrop-filter: blur(6px);
}

.about-feature-card::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 20% 20%, rgba(37, 99, 235, 0.12), transparent 60%),
              radial-gradient(circle at 85% 15%, rgba(59, 130, 246, 0.18), transparent 55%);
  z-index: 0;
}

.about-feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(37, 99, 235, 0.18);
}

.feature-card-icon {
  position: relative;
  z-index: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-lg);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.feature-card-icon i {
  font-size: var(--text-2xl);
  color: white;
}

.about-feature-card p {
  margin-bottom: var(--space-md);
  color: var(--color-gray-600);
  line-height: 1.7;
  text-align: justify;
}

.about-feature-card .about-heading {
  position: relative;
  z-index: 1;
  font-size: var(--text-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-lg);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.objective-body,
.philosophy-body {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--space-md);
}

.objective-body p,
.philosophy-body p {
  margin-bottom: 0;
}

.philosophy-list {
  list-style: none;
  padding-left: 0;
  margin-top: var(--space-xl);
  display: grid;
  gap: var(--space-md);
  counter-reset: philosophy-counter;
}

.philosophy-list li {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg);
  background: rgba(255, 255, 255, 0.95);
  border: 1px solid rgba(37, 99, 235, 0.08);
  border-radius: var(--radius-lg);
  box-shadow: 0 6px 18px rgba(15, 23, 42, 0.06);
  transition: all var(--transition-base);
  counter-increment: philosophy-counter;
  color: var(--color-gray-600);
  line-height: 1.65;
  text-align: left;
}

.philosophy-list li::before {
  content: counter(philosophy-counter);
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  color: white;
  font-weight: var(--font-weight-bold);
  font-size: var(--text-base);
  border-radius: 50%;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.2);
}

.philosophy-item {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.philosophy-item-title {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
}

.philosophy-item-description {
  margin: 0;
  color: var(--color-gray-600);
}

.philosophy-list li:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
  transform: translateY(-2px);
}

.about-values {
  margin-top: var(--space-3xl);
}

.values-grid {
  display: grid;
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}

.value-card {
  text-align: center;
  padding: var(--space-xl);
  background-color: var(--bg-primary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition-normal);
}

.value-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.value-icon {
  font-size: var(--text-3xl);
  color: var(--color-primary);
  margin-bottom: var(--space-md);
}

.value-title {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-sm);
}

.value-description {
  color: var(--color-gray-600);
}

/* Desktop About Layout */
@media (min-width: 768px) {
  .about-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-2xl);
    justify-items: stretch;
  }
  
  .values-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .values-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* =============================================================================
   EXPERTISE SECTION
   ============================================================================= */

.expertise-grid {
  display: grid;
  gap: var(--space-2xl);
}

.expertise-category {
  background-color: var(--bg-primary);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
}

.category-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.category-icon {
  font-size: var(--text-2xl);
  color: var(--color-primary);
}

.category-title {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
}

.skills-grid {
  display: grid;
  gap: var(--space-lg);
}

.skill-item {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-sm);
}

.skill-name {
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
}

.skill-bar {
  height: 8px;
  background-color: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.skill-progress {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

/* Desktop Expertise Layout */
@media (min-width: 768px) {
  .expertise-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-xl);
  }
}

@media (min-width: 1024px) {
  .expertise-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-lg);
  }
}

/* =============================================================================
   EXPERIENCE SECTION (TIMELINE)
   ============================================================================= */

.timeline {
  position: relative;
  padding-left: var(--space-xl);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 12px;
  top: 0;
  bottom: 0;
  width: 2px;
  background-color: var(--color-gray-300);
}

.timeline-item {
  position: relative;
  margin-bottom: var(--space-3xl);
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -18px;
  top: 6px;
  width: 12px;
  height: 12px;
  background-color: var(--color-primary);
  border-radius: var(--radius-full);
  border: 3px solid var(--bg-primary);
  box-shadow: 0 0 0 3px var(--color-gray-300);
}

.timeline-date {
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}

.timeline-content {
  background-color: var(--bg-primary);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
}

.timeline-title {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
}

.timeline-company {
  font-size: var(--text-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-primary);
  margin-bottom: var(--space-md);
}

.timeline-description {
  color: var(--color-gray-600);
  margin-bottom: var(--space-md);
  text-align: justify;
  line-height: 1.7;
}

.timeline-achievements {
  list-style: none;
  margin-bottom: var(--space-md);
}

.timeline-achievements li {
  padding: var(--space-xs) 0;
  color: var(--color-gray-600);
  position: relative;
  padding-left: var(--space-lg);
}

.timeline-achievements li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--color-secondary);
  font-weight: var(--font-weight-bold);
}

.timeline-skills {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.skill-tag {
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--bg-tertiary);
  color: var(--color-primary);
  font-size: var(--text-xs);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-primary);
}

/* Desktop Timeline Layout */
@media (min-width: 768px) {
  .timeline {
    padding-left: var(--space-2xl);
  }
  
  .timeline::before {
    left: 24px;
  }
  
  .timeline-item::before {
    left: -30px;
    width: 16px;
    height: 16px;
  }
}

/* -----------------------------------------------------------------------------
   Key Initiatives + Details toggle (thêm trải nghiệm mở rộng, không phá layout)
   ----------------------------------------------------------------------------- */
.key-initiatives {
  margin-top: var(--space-md);
}

.key-initiatives .key-title {
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
}

.key-initiatives .key-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: var(--space-md);
}

.key-initiatives .key-list li {
  padding: var(--space-xs) 0;
  color: var(--color-gray-600);
  position: relative;
  padding-left: var(--space-lg);
}

.key-initiatives .key-list li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--color-secondary);
  font-weight: var(--font-weight-bold);
}

.initiatives-details {
  margin-top: var(--space-sm);
}

.initiatives-details summary {
  cursor: pointer;
  color: var(--color-primary);
  font-weight: var(--font-weight-medium);
  list-style: none;
}

/* Ẩn marker mặc định của summary để tùy biến */
.initiatives-details summary::-webkit-details-marker {
  display: none;
}

/* Icon mũi tên cho toggle */
.initiatives-details summary::after {
  content: '▼';
  display: inline-block;
  margin-left: 8px;
  font-size: 0.75em;
  transform: translateY(-1px);
  transition: transform var(--transition-fast);
}

.initiatives-details[open] summary::after {
  transform: rotate(180deg) translateY(1px);
}

.details-content {
  margin-top: var(--space-md);
}

.details-content h4 {
  font-size: var(--text-base);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin: var(--space-sm) 0;
}

.details-content ul {
  list-style: none;
  padding-left: 0;
  margin-bottom: var(--space-md);
}

.details-content li {
  padding: var(--space-xs) 0;
  color: var(--color-gray-600);
  position: relative;
  padding-left: var(--space-lg);
}

.details-content li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--color-secondary);
  font-weight: var(--font-weight-bold);
}

/* =============================================================================
   EDUCATION SECTION
   ============================================================================= */

.education-grid {
  display: grid;
  gap: var(--space-2xl);
}

.education-item {
  display: flex;
  gap: var(--space-xl);
  background-color: var(--bg-primary);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition-normal);
}

.education-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.education-highlight {
  background: linear-gradient(135deg, #f0f9ff 0%, #ffffff 100%);
  border: 2px solid var(--color-primary-light);
}

.education-icon {
  flex-shrink: 0;
  width: 60px;
  height: 60px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--text-2xl);
}

.education-content {
  flex: 1;
}

.education-degree {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
}

.education-school {
  font-size: var(--text-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-primary);
  margin-bottom: var(--space-xs);
}

.education-date {
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  margin-bottom: var(--space-md);
}

.education-status {
  margin-bottom: var(--space-md);
}

.education-gpa {
  margin-bottom: var(--space-md);
}

.gpa-badge {
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background: linear-gradient(135deg, var(--color-primary), #3b82f6dd);
  color: white;
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-full);
}

.status-badge {
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background: linear-gradient(135deg, var(--color-secondary), #10b981dd);
  color: white;
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-full);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.8;
  }
}

.education-description {
  color: var(--color-gray-600);
  margin-bottom: var(--space-md);
  line-height: var(--line-height-relaxed);
}

.education-skills {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

/* Responsive Education Layout */
@media (max-width: 768px) {
  .education-item {
    flex-direction: column;
    gap: var(--space-md);
  }
  
  .education-icon {
    width: 50px;
    height: 50px;
    font-size: var(--text-xl);
  }
}

/* Desktop layout - giữ xếp dọc full-width cho dễ đọc */
@media (min-width: 1024px) {
  .education-grid {
    grid-template-columns: 1fr;
    max-width: 900px;
    margin: 0 auto;
  }
}

/* =============================================================================
   ACHIEVEMENTS SECTION
   ============================================================================= */

.achievements-grid {
  display: grid;
  gap: var(--space-3xl);
}

.achievement-card {
  background-color: var(--bg-primary);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
  text-align: center;
}

.achievement-icon {
  margin-bottom: var(--space-lg);
}

.achievement-icon i {
  font-size: var(--text-4xl);
  color: var(--color-primary);
}

.achievement-title {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-lg);
}

.certification-list {
  text-align: left;
}

.cert-item {
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

.cert-item:last-child {
  border-bottom: none;
}

.cert-org {
  display: block;
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  margin-top: var(--space-xs);
}

.cert-link {
  display: inline-block;
  margin-top: var(--space-xs);
  font-size: var(--text-sm);
  color: var(--color-primary);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.cert-link:hover {
  text-decoration: underline;
  color: var(--color-primary-dark);
}

.cert-link i {
  font-size: 0.875em;
  margin-right: 4px;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-lg);
}

.metric-item {
  text-align: center;
}

.metric-value {
  display: block;
  font-size: var(--text-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
}

.metric-label {
  font-size: var(--text-sm);
  color: var(--color-gray-600);
}

.community-list {
  list-style: none;
  text-align: left;
}

.community-list li {
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-gray-200);
  color: var(--color-gray-600);
}

.community-list li:last-child {
  border-bottom: none;
}

/* Desktop Achievements Layout */
@media (min-width: 768px) {
  .achievements-grid {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  }
}

/* =============================================================================
   CONTACT SECTION
   ============================================================================= */

.contact-grid {
  display: grid;
  gap: var(--space-3xl);
}

.contact-heading {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-md);
}

.contact-description {
  color: var(--color-gray-600);
  margin-bottom: var(--space-xl);
  text-align: justify;
  line-height: 1.7;
}

.download-cv-section {
  margin: var(--space-xl) 0;
}

.download-cv-section .btn {
  margin: 0;
}

.contact-methods {
  margin-bottom: var(--space-xl);
}

.contact-method {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}

.contact-icon {
  font-size: var(--text-xl);
  color: var(--color-primary);
  margin-top: var(--space-xs);
}

.contact-method-title {
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
}

.contact-link {
  color: var(--color-primary);
  text-decoration: none;
}

.contact-link:hover,
.contact-link:focus {
  text-decoration: underline;
}

.contact-text {
  color: var(--color-gray-600);
}

.social-links {
  display: flex;
  gap: var(--space-md);
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background-color: var(--color-gray-100);
  color: var(--color-gray-600);
  border-radius: var(--radius-full);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.social-link:hover,
.social-link:focus {
  background-color: var(--color-primary);
  color: white;
  transform: translateY(-2px);
}

/* Form Styles */
.contact-form-container {
  background-color: var(--bg-primary);
  padding: var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
}

.form-group {
  margin-bottom: var(--space-lg);
}

.form-label {
  display: block;
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
  margin-bottom: var(--space-sm);
}

.form-input {
  width: 100%;
  padding: var(--space-md);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: var(--text-base);
  transition: all var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-input-error {
  border-color: var(--color-error);
}

.form-error {
  display: block;
  color: var(--color-error);
  font-size: var(--text-sm);
  margin-top: var(--space-xs);
}

textarea.form-input {
  resize: vertical;
  min-height: 120px;
}

/* Desktop Contact Layout */
@media (min-width: 768px) {
  .contact-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-4xl);
  }
}

/* =============================================================================
   FOOTER
   ============================================================================= */

.footer {
  background-color: var(--color-gray-900);
  color: var(--color-gray-300);
  padding: var(--space-xl) 0;
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  text-align: center;
}

.footer-note {
  font-size: var(--text-sm);
  color: var(--color-gray-400);
}

.footer-right {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer-link {
  color: var(--color-gray-400);
  text-decoration: none;
  font-size: var(--text-sm);
  transition: color var(--transition-fast);
}

.footer-link:hover,
.footer-link:focus {
  color: var(--color-primary-light);
}

/* Desktop Footer Layout */
@media (min-width: 768px) {
  .footer-content {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    text-align: left;
  }
  
  .footer-right {
    flex-direction: row;
    gap: var(--space-lg);
  }
}

/* =============================================================================
   ANIMATIONS AND INTERACTIONS
   ============================================================================= */

/* Smooth entrance animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Hover effects for interactive elements */
.value-card,
.expertise-category,
.timeline-content,
.achievement-card {
  transition: all var(--transition-normal);
}

.value-card:hover,
.expertise-category:hover,
.achievement-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

/* Focus indicators for accessibility */
.nav-link:focus,
.btn:focus,
.form-input:focus,
.social-link:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* =============================================================================
   RESPONSIVE DESIGN ENHANCEMENTS
   ============================================================================= */

/* Large screens - optimize for readability */
@media (min-width: 1200px) {
  .hero-description,
  .section-subtitle {
    font-size: var(--text-xl);
  }
}

/* Reduce animations for users who prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  .header {
    transition: none;
  }
  
  .skill-progress {
    transition: none;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --color-primary: #0066cc;
    --color-secondary: #009900;
    --color-gray-600: #000000;
    --color-gray-700: #000000;
  }
  
  .btn {
    border-width: 2px;
  }
  
  .form-input {
    border-width: 2px;
  }
}

/* Print styles */
@media print {
  .header,
  .nav-toggle,
  .hero-actions,
  .contact-form-container,
  .footer {
    display: none;
  }
  
  .hero {
    padding-top: var(--space-xl);
  }
  
  body {
    font-size: 12pt;
    line-height: 1.4;
    color: black;
  }
  
  .section-title {
    page-break-after: avoid;
  }
  
  .timeline-item {
    page-break-inside: avoid;
  }
}

/* Award Section Styles */
.award-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.award-item {
  padding: var(--space-sm);
  border-left: 3px solid var(--color-accent);
  background: rgba(var(--color-accent-rgb), 0.05);
  border-radius: 4px;
}

.award-item strong {
  display: block;
  color: var(--color-accent);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.award-description {
  margin: 0;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

/* =============================================================================
   PROFESSIONAL NOTIFICATIONS
   ============================================================================= */

.notification {
  position: fixed;
  top: var(--space-lg);
  right: var(--space-lg);
  z-index: var(--z-tooltip);
  max-width: 400px;
  background: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--color-gray-200);
  overflow: hidden;
  animation: slideInRight 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.notification-success {
  border-left: 4px solid var(--color-success);
}

.notification-error {
  border-left: 4px solid var(--color-error);
}

.notification-info {
  border-left: 4px solid var(--color-info);
}

.notification-content {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md);
  color: var(--color-gray-700);
  font-size: var(--text-sm);
  line-height: var(--line-height-normal);
}

.notification-content i {
  flex-shrink: 0;
  font-size: var(--text-base);
}

.notification-success .notification-content i {
  color: var(--color-success);
}

.notification-error .notification-content i {
  color: var(--color-error);
}

.notification-info .notification-content i {
  color: var(--color-info);
}

.notification-close {
  position: absolute;
  top: var(--space-xs);
  right: var(--space-xs);
  background: none;
  border: none;
  color: var(--color-gray-400);
  cursor: pointer;
  padding: var(--space-xs);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast);
}

.notification-close:hover {
  color: var(--color-gray-600);
}

.notification-fade-out {
  animation: slideOutRight 0.3s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes slideInRight {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes slideOutRight {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(100%);
    opacity: 0;
  }
}

/* =============================================================================
   SCROLL ANIMATIONS
   ============================================================================= */

.animate-in {
  animation: fadeInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

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

/* Initial state for animated elements */
section:not(.hero),
.timeline-item,
.expertise-category,
.value-card,
.achievement-card,
.education-item {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1), 
              transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Enhanced button interactions */
.btn {
  position: relative;
  overflow: hidden;
  transition: all var(--transition-normal) cubic-bezier(0.4, 0, 0.2, 1);
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: left 0.5s;
}

.btn:hover::before {
  left: 100%;
}

.btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
  transform: none;
}

.btn:disabled::before {
  display: none;
}

/* Enhanced form focus states */
.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  transform: translateY(-1px);
}

.form-input-error {
  border-color: var(--color-error);
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.form-error {
  color: var(--color-error);
  font-size: var(--text-xs);
  margin-top: var(--space-xs);
  display: block;
  min-height: 1.2em;
}

/* Enhanced skill bars animation */
.skill-progress {
  transition: width 1s cubic-bezier(0.4, 0, 0.2, 1) 0.3s;
}

.expertise-category.animate-in .skill-progress {
  animation: expandWidth 1s cubic-bezier(0.4, 0, 0.2, 1) 0.5s forwards;
}

@keyframes expandWidth {
  from {
    width: 0;
  }
}

/* Professional loading spinner */
.fa-spinner {
  animation: spin 1s linear infinite;
}

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

/* =============================================================================
   LOADING STATES & PAGE TRANSITIONS
   ============================================================================= */

body {
  opacity: 0;
  transition: opacity 0.3s ease-in-out;
}

body.loaded {
  opacity: 1;
}

/* Hero loading animations */
.hero-content > * {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.hero-loaded .hero-content > * {
  opacity: 1;
  transform: translateY(0);
}

.hero-loaded .hero-title {
  transition-delay: 0.1s;
}

.hero-loaded .hero-description {
  transition-delay: 0.2s;
}

.hero-loaded .hero-actions {
  transition-delay: 0.3s;
}

.hero-loaded .hero-stats {
  transition-delay: 0.4s;
}

.hero-visual {
  opacity: 0;
  transform: scale(0.9) translateY(20px);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.hero-loaded .hero-visual {
  opacity: 1;
  transform: scale(1) translateY(0);
  transition-delay: 0.2s;
}

/* Enhanced mobile responsiveness for notifications */
@media (max-width: 768px) {
  .notification {
    left: var(--space-md);
    right: var(--space-md);
    max-width: none;
  }
  
  @keyframes slideInRight {
    from {
      transform: translateY(-100%);
      opacity: 0;
    }
    to {
      transform: translateY(0);
      opacity: 1;
    }
  }
  
  @keyframes slideOutRight {
    from {
      transform: translateY(0);
      opacity: 1;
    }
    to {
      transform: translateY(-100%);
      opacity: 0;
    }
  }
}

/* Professional focus management */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--color-primary);
  color: white;
  padding: 8px;
  text-decoration: none;
  border-radius: var(--radius-sm);
  z-index: var(--z-tooltip);
  transition: top 0.3s;
}

.skip-link:focus {
  top: 6px;
}

/* Enhanced print styles */
@media print {
  .header,
  .notification,
  .btn,
  .social-links {
    display: none !important;
  }
  
  .hero {
    page-break-after: always;
  }
  
  body {
    font-size: 12pt;
    line-height: 1.4;
  }
  
  .section-title {
    color: #000 !important;
    page-break-after: avoid;
  }
}

/* =============================================================================
   PROFESSIONAL CERTIFICATIONS SECTION
   ============================================================================= */

.certifications-separate {
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
  padding: var(--space-4xl) 0;
  position: relative;
  overflow: hidden;
}

.certifications-separate::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 50%, rgba(37, 99, 235, 0.05) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(16, 185, 129, 0.05) 0%, transparent 50%);
  pointer-events: none;
}

.certifications-separate .container {
  position: relative;
  z-index: 1;
}

.certifications-separate .section-title {
  color: var(--color-gray-900);
}

.certifications-separate .section-subtitle {
  color: var(--color-gray-600);
}

.certifications-grid-separate {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  margin-top: var(--space-3xl);
}

@media (min-width: 768px) {
  .certifications-grid-separate {
    grid-template-columns: repeat(3, 1fr);
  }
}

.cert-category-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  border: 1px solid var(--color-gray-200);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.cert-category-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(37, 99, 235, 0.15);
  border-color: var(--color-primary);
}

.cert-category-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-md);
  border-bottom: 2px solid var(--color-gray-200);
}

.cert-category-header i {
  font-size: var(--text-2xl);
  color: var(--color-primary);
  background: var(--bg-tertiary);
  padding: var(--space-sm);
  border-radius: var(--radius-md);
}

.cert-category-header h3 {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-semibold);
  margin: 0;
  color: var(--color-gray-900);
}

.cert-items-compact {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.cert-compact {
  padding: var(--space-md);
  background: var(--color-gray-50);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-primary);
  transition: all var(--transition-fast);
}

.cert-compact:hover {
  background: var(--bg-tertiary);
  transform: translateX(4px);
  border-left-color: var(--color-secondary);
}

.cert-compact-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-xs);
  gap: var(--space-sm);
}

.cert-compact-header strong {
  font-size: var(--text-base);
  color: var(--color-gray-900);
  font-weight: var(--font-weight-semibold);
  line-height: 1.4;
}

.cert-badge {
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-weight-medium);
  white-space: nowrap;
  flex-shrink: 0;
}

.cert-badge.cert-active {
  background: var(--color-success);
  color: white;
}

.cert-org-compact {
  display: block;
  font-size: var(--text-sm);
  color: var(--color-gray-600);
  margin-top: var(--space-xs);
}

.cert-link-compact {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  margin-top: var(--space-sm);
  font-size: var(--text-sm);
  color: var(--color-primary);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-fast);
}

.cert-link-compact:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.cert-link-compact i {
  font-size: 0.875em;
}