/* CSS Custom Properties */
:root {
  /* Colors - Enhanced Palette */
  --color-primary: #3b82f6;
  --color-primary-dark: #2563eb;
  --color-primary-light: #60a5fa;
  --color-secondary: #64748b;
  --color-accent: #f59e0b;
  --color-accent-light: #fbbf24;
  --color-success: #10b981;
  --color-error: #ef4444;
  --color-warning: #f59e0b;

  /* Gradient Colors */
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);

  /* Neutral colors */
  --color-white: #ffffff;
  --color-gray-50: #f8fafc;
  --color-gray-100: #f1f5f9;
  --color-gray-200: #e2e8f0;
  --color-gray-300: #cbd5e1;
  --color-gray-400: #94a3b8;
  --color-gray-500: #64748b;
  --color-gray-600: #475569;
  --color-gray-700: #334155;
  --color-gray-800: #1e293b;
  --color-gray-900: #0f172a;

  /* Dark mode colors */
  --color-bg-primary: var(--color-white);
  --color-bg-secondary: var(--color-gray-50);
  --color-bg-tertiary: var(--color-gray-100);
  --color-text-primary: var(--color-gray-900);
  --color-text-secondary: var(--color-gray-600);
  --color-text-muted: var(--color-gray-500);
  --color-border: var(--color-gray-200);
  --color-shadow: rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-family-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono",
    Consolas, "Courier New", monospace;

  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;

  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* Spacing */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;
  --spacing-20: 5rem;
  --spacing-24: 6rem;

  /* Layout */
  --container-max-width: 1200px;
  --border-radius-sm: 0.375rem;
  --border-radius-md: 0.5rem;
  --border-radius-lg: 0.75rem;
  --border-radius-xl: 1rem;

  /* Shadows - Enhanced */
  --shadow-sm: 0 1px 2px 0 var(--color-shadow);
  --shadow-md: 0 4px 6px -1px var(--color-shadow);
  --shadow-lg: 0 10px 15px -3px var(--color-shadow);
  --shadow-xl: 0 20px 25px -5px var(--color-shadow);
  --shadow-2xl: 0 25px 50px -12px var(--color-shadow);
  --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.3);
  --shadow-glow-accent: 0 0 20px rgba(245, 158, 11, 0.3);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;

  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal: 1040;
  --z-popover: 1050;
  --z-tooltip: 1060;
}

/* Dark mode */
[data-theme="dark"] {
  --color-bg-primary: var(--color-gray-900);
  --color-bg-secondary: var(--color-gray-800);
  --color-bg-tertiary: var(--color-gray-700);
  --color-text-primary: var(--color-white);
  --color-text-secondary: var(--color-gray-300);
  --color-text-muted: var(--color-gray-400);
  --color-border: var(--color-gray-700);
  --color-shadow: rgba(0, 0, 0, 0.3);
}

[data-theme="dark"] .header {
  background-color: rgba(15, 23, 42, 0.95);
}

/* Reset and base styles */
*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  transition: background-color var(--transition-normal),
    color var(--transition-normal);
}

/* Skip link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--color-primary);
  color: var(--color-white);
  padding: var(--spacing-2) var(--spacing-4);
  text-decoration: none;
  border-radius: var(--border-radius-sm);
  z-index: var(--z-tooltip);
  font-weight: var(--font-weight-medium);
}

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

/* Focus styles */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-text-primary);
}

h1 {
  font-size: var(--font-size-4xl);
}

h2 {
  font-size: var(--font-size-3xl);
}

h3 {
  font-size: var(--font-size-2xl);
}

h4 {
  font-size: var(--font-size-xl);
}

h5 {
  font-size: var(--font-size-lg);
}

h6 {
  font-size: var(--font-size-base);
}

p {
  margin-bottom: var(--spacing-4);
  color: var(--color-text-secondary);
}

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

a:hover {
  color: var(--color-primary-dark);
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--border-radius-sm);
}

/* Container */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-4);
}

/* Header */
.header {
  background-color: rgba(255, 255, 255, 0.95);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-4) 0;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding-left: var(--spacing-4);
  padding-right: var(--spacing-4);
  position: relative;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-2);
  border-radius: var(--border-radius-md);
  transition: background-color var(--transition-fast);
  min-width: 44px;
  min-height: 44px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
}

.mobile-menu-toggle:hover {
  background-color: var(--color-bg-secondary);
  cursor: pointer;
}

.mobile-menu-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.hamburger-line {
  width: 24px;
  height: 2px;
  background-color: var(--color-text-primary);
  transition: all var(--transition-fast);
  border-radius: 1px;
}

.mobile-menu-toggle[aria-expanded="true"] .hamburger-line:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

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

.mobile-menu-toggle[aria-expanded="true"] .hamburger-line:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

.logo a {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
}

.nav-list {
  display: flex;
  list-style: none;
  gap: var(--spacing-6);
  margin: 0;
  padding: 0;
}

/* Mobile Navigation */
.nav-list.mobile-open {
  display: flex;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background-color: var(--color-bg-primary);
  flex-direction: column;
  padding: var(--spacing-4);
  box-shadow: var(--shadow-lg);
  border-top: 1px solid var(--color-border);
  gap: var(--spacing-2);
  z-index: var(--z-dropdown);
}

.nav-link {
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  padding: var(--spacing-3) var(--spacing-4);
  position: relative;
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
  display: block;
}

.nav-list.mobile-open .nav-link {
  padding: var(--spacing-3) var(--spacing-4);
  border-radius: var(--border-radius-md);
  background-color: transparent;
}

.nav-list.mobile-open .nav-link:hover,
.nav-list.mobile-open .nav-link:focus {
  background-color: var(--color-bg-secondary);
}

.nav-link:hover,
.nav-link:focus {
  color: var(--color-primary);
  cursor: pointer;
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition-fast);
}

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

.nav-link.active {
  color: var(--color-primary);
  font-weight: var(--font-weight-semibold);
}

/* Theme toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  padding: var(--spacing-2);
  cursor: pointer;
  transition: all var(--transition-fast);
  min-width: 44px;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background-color: var(--color-bg-secondary);
  border-color: var(--color-primary);
  cursor: pointer;
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.theme-icon {
  font-size: var(--font-size-lg);
}

/* Main content */
.main {
  min-height: calc(100vh - 80px);
}

/* Section styles */
section {
  padding: var(--spacing-16) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-12);
}

/* Hero section */
.hero {
  background: linear-gradient(
    135deg,
    var(--color-bg-secondary) 0%,
    var(--color-bg-tertiary) 100%
  );
  padding: var(--spacing-20) 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-primary);
  opacity: 0.1;
  z-index: 1;
}

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

.hero-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.hero-title {
  margin-bottom: var(--spacing-4);
}

.highlight {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  color: transparent;
  display: inline-block;
  font-weight: var(--font-weight-bold);
  position: relative;
  transition: all 0.3s ease;
}

/* Fallback for browsers that don't support background-clip: text */
@supports not (background-clip: text) {
  .highlight {
    background: none;
    -webkit-text-fill-color: initial;
    color: var(--color-primary);
  }
}

.hero-subtitle {
  font-size: var(--font-size-xl);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-6);
}

.hero-description {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-8);
}

.hero-actions {
  display: flex;
  gap: var(--spacing-4);
  justify-content: center;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-3) var(--spacing-6);
  border-radius: var(--border-radius-md);
  font-weight: var(--font-weight-medium);
  text-decoration: none;
  transition: all var(--transition-normal);
  border: none;
  cursor: pointer;
  min-height: 44px;
  min-width: 44px;
  position: relative;
  overflow: hidden;
}

.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 var(--transition-slow);
}

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

.btn-primary {
  background: var(--gradient-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover,
.btn-primary:focus {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  cursor: pointer;
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
  position: relative;
}

.btn-secondary::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 100%;
  background: var(--gradient-primary);
  transition: width var(--transition-normal);
  z-index: -1;
}

.btn-secondary:hover::after,
.btn-secondary:focus::after {
  width: 100%;
}

.btn-secondary:hover,
.btn-secondary:focus {
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  cursor: pointer;
}

/* About section */
.about-content {
  display: grid;
  gap: var(--spacing-12);
  align-items: center;
}

.about-text p {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-6);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-6);
}

.stat {
  text-align: center;
  padding: var(--spacing-6);
  background-color: var(--color-bg-secondary);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--color-border);
}

.stat-number {
  display: block;
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
  margin-bottom: var(--spacing-2);
}

.stat-label {
  color: var(--color-text-secondary);
  font-weight: var(--font-weight-medium);
}

/* Projects section */
.projects {
  background-color: var(--color-bg-secondary);
}

.projects-grid {
  display: grid;
  gap: var(--spacing-8);
  grid-template-columns: 1fr;
}

.project-card {
  background-color: var(--color-bg-primary);
  border-radius: var(--border-radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  border: 1px solid var(--color-border);
  position: relative;
}

.project-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-normal);
  z-index: 1;
}

.project-card:hover::before {
  opacity: 0.05;
  pointer-events: none;
}

.project-card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: var(--shadow-2xl);
}

.project-card:hover .project-image {
  transform: scale(1.05);
}

.project-image {
  height: 200px;
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  transition: transform var(--transition-slow);
}

.project-image::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    45deg,
    transparent 30%,
    rgba(255, 255, 255, 0.1) 50%,
    transparent 70%
  );
  transform: translateX(-100%);
  transition: transform var(--transition-slow);
}

.project-card:hover .project-image::before {
  transform: translateX(100%);
}

.project-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
}

.project-icon {
  font-size: var(--font-size-2xl);
  color: var(--color-white);
  font-weight: var(--font-weight-bold);
  text-align: center;
  letter-spacing: 0.05em;
}

.project-content {
  padding: var(--spacing-6);
  position: relative;
  z-index: 2;
}

.project-title {
  margin-bottom: var(--spacing-3);
  color: var(--color-text-primary);
}

.project-description {
  margin-bottom: var(--spacing-4);
}

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-2);
  margin-bottom: var(--spacing-4);
}

.tech-tag {
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  padding: var(--spacing-1) var(--spacing-3);
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  border: 1px solid var(--color-border);
}

.project-links {
  display: flex;
  gap: var(--spacing-4);
  position: relative;
  z-index: 4;
}

.project-link {
  color: var(--color-primary);
  font-weight: var(--font-weight-medium);
  padding: var(--spacing-2) 0;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-fast);
  text-decoration: none;
  display: inline-block;
  position: relative;
  z-index: 3;
}

.project-link:hover {
  border-bottom-color: var(--color-primary);
  cursor: pointer;
  color: var(--color-primary-dark);
}

.project-link:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--border-radius-sm);
}

/* Skills section */
.skills-grid {
  display: grid;
  gap: var(--spacing-8);
  grid-template-columns: 1fr;
}

.skill-category {
  background-color: var(--color-bg-secondary);
  padding: var(--spacing-8);
  border-radius: var(--border-radius-xl);
  border: 1px solid var(--color-border);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.skill-category::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-normal);
  z-index: 1;
}

.skill-category:hover::before {
  opacity: 0.05;
}

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

.skill-category-title {
  margin-bottom: var(--spacing-6);
  text-align: center;
  color: var(--color-primary);
  position: relative;
  z-index: 2;
}

.skill-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-3);
  justify-content: center;
  position: relative;
  z-index: 2;
}

.skill-item {
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  padding: var(--spacing-2) var(--spacing-4);
  border-radius: var(--border-radius-md);
  font-weight: var(--font-weight-medium);
  border: 1px solid var(--color-border);
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.skill-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  transition: left var(--transition-normal);
  z-index: -1;
}

.skill-item:hover::before {
  left: 0;
}

.skill-item:hover {
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
  cursor: pointer;
}

/* Contact section */
.contact {
  background-color: var(--color-bg-secondary);
}

.contact-content {
  display: grid;
  gap: var(--spacing-12);
  grid-template-columns: 1fr;
}

.contact-subtitle {
  margin-bottom: var(--spacing-4);
  color: var(--color-primary);
}

.contact-description {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-8);
}

.contact-methods {
  display: grid;
  gap: var(--spacing-4);
}

.contact-method {
  display: flex;
  align-items: center;
}

.contact-link {
  color: var(--color-text-primary);
  font-weight: var(--font-weight-medium);
}

.contact-link:hover {
  cursor: pointer;
}

.contact-text {
  color: var(--color-text-primary);
  font-weight: var(--font-weight-medium);
}

/* Form styles */
.contact-form {
  background-color: var(--color-bg-primary);
  padding: var(--spacing-8);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--color-border);
}

.form-group {
  margin-bottom: var(--spacing-6);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-2);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
}

.form-input {
  width: 100%;
  padding: var(--spacing-3) var(--spacing-4);
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius-md);
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  font-size: var(--font-size-base);
  transition: border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  transform: translateY(-1px);
}

.form-input:invalid:not(:focus):not(:placeholder-shown) {
  border-color: var(--color-error);
}

.form-input:valid:not(:focus):not(:placeholder-shown) {
  border-color: var(--color-success);
}

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

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

.form-error {
  color: var(--color-error);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-1);
  min-height: 1.25rem;
}

.form-actions {
  margin-top: var(--spacing-8);
}

/* Loading animation for submit button */
.btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
  position: relative;
}

.btn:disabled::after {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  border: 2px solid transparent;
  border-top: 2px solid currentColor;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-left: var(--spacing-2);
}

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

/* Success Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal.show {
  opacity: 1;
  visibility: visible;
}

.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.modal-content {
  position: relative;
  background-color: var(--color-bg-primary);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-2xl);
  max-width: 500px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-normal);
}

.modal.show .modal-content {
  transform: scale(1) translateY(0);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-6);
  border-bottom: 1px solid var(--color-border);
}

.modal-title {
  margin: 0;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semibold);
}

.modal-close {
  background: none;
  border: none;
  font-size: var(--font-size-2xl);
  color: var(--color-text-secondary);
  cursor: pointer;
  padding: var(--spacing-2);
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
  min-width: 44px;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-close:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-text-primary);
}

.modal-close:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.close-icon {
  font-weight: var(--font-weight-bold);
  line-height: 1;
}

.modal-body {
  padding: var(--spacing-6);
  text-align: center;
}

.modal-icon {
  margin-bottom: var(--spacing-4);
  display: flex;
  justify-content: center;
}

.modal-message {
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
  line-height: var(--line-height-relaxed);
  margin: 0;
}

.modal-footer {
  padding: var(--spacing-6);
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.modal-btn {
  min-width: 120px;
}

/* Modal animations */
@keyframes modalFadeIn {
  from {
    opacity: 0;
    transform: scale(0.9) translateY(20px);
  }
  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

@keyframes modalFadeOut {
  from {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
  to {
    opacity: 0;
    transform: scale(0.9) translateY(20px);
  }
}

/* Footer */
.footer {
  background-color: var(--color-bg-tertiary);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-8) 0;
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
  align-items: center;
  text-align: center;
}

.footer-info p {
  color: var(--color-text-secondary);
  margin: 0;
}

.footer-link {
  color: var(--color-text-secondary);
  font-weight: var(--font-weight-medium);
}

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

/* Mobile Responsive Design */
@media (max-width: 639px) {
  .mobile-menu-toggle {
    display: flex;
  }

  .nav-list {
    display: none;
  }

  .nav-list.mobile-open {
    display: flex;
  }

  .hero {
    padding: var(--spacing-12) 0;
  }

  .hero-title {
    font-size: var(--font-size-3xl);
    line-height: var(--line-height-tight);
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 280px;
  }

  .section-title {
    font-size: var(--font-size-2xl);
  }

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

  .projects-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-6);
  }

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

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

  .footer-content {
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-3);
  }

  .container {
    padding: 0 var(--spacing-3);
  }
}

/* Tablet and Desktop */
@media (min-width: 640px) {
  .hero-title {
    font-size: var(--font-size-5xl);
  }

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

  .projects-grid {
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  }

  .skills-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  }

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

  .footer-content {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

@media (min-width: 1024px) {
  .hero {
    padding: var(--spacing-24) 0;
  }

  .hero-title {
    font-size: 4rem;
  }

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

  .skills-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .nav-list {
    gap: var(--spacing-8);
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}

/* High contrast mode */
@media (prefers-contrast: high) {
  :root {
    --color-border: var(--color-text-primary);
    --color-shadow: rgba(0, 0, 0, 0.5);
  }

  .btn-secondary {
    border-width: 3px;
  }

  .form-input:focus {
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.3);
  }
}