/* ============================================
   PORTFOLIO WEBSITE - DESIGN SYSTEM
   ============================================ */

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

/* ============================================
   CSS VARIABLES - THEME SYSTEM
   ============================================ */

:root {
  /* Light Mode Colors - Olive & White */
  --color-primary: #6b8e23;
  --color-primary-dark: #556b1a;
  --color-primary-light: #8ab83a;
  --color-secondary: #808000;
  --color-background: #ffffff;
  --color-surface: #f5f5f5;
  --color-surface-elevated: #fafafa;
  --color-text: #1a1a1a;
  --color-text-secondary: #4a4a4a;
  --color-text-muted: #6b6b6b;
  --color-border: #e0e0e0;
  --color-shadow: rgba(0, 0, 0, 0.1);
  --color-shadow-hover: rgba(0, 0, 0, 0.15);

  /* Typography */
  --font-primary:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-code: "Fira Code", "Courier New", monospace;

  /* Font Sizes */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

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

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Shadows */
  --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);
}

/* Dark Mode Colors - Black & Very Light Yellow */
[data-theme="dark"] {
  --color-primary: #f5f4e8;
  --color-primary-dark: #e8e6d5;
  --color-primary-light: #fffef0;
  --color-secondary: #fffef0;
  --color-background: #0a0a0a;
  --color-surface: #1a1a1a;
  --color-surface-elevated: #252525;
  --color-text: #fffef0;
  --color-text-secondary: #e8e6d5;
  --color-text-muted: #a8a79c;
  --color-border: #2a2a2a;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --color-shadow-hover: rgba(0, 0, 0, 0.5);
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-primary);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-background);
  transition:
    background-color var(--transition-base),
    color var(--transition-base);
  overflow-x: hidden;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

h1 {
  font-size: var(--text-5xl);
}
h2 {
  font-size: var(--text-4xl);
}
h3 {
  font-size: var(--text-3xl);
}
h4 {
  font-size: var(--text-2xl);
}
h5 {
  font-size: var(--text-xl);
}
h6 {
  font-size: var(--text-lg);
}

p {
  margin-bottom: var(--space-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);
}

code {
  font-family: var(--font-code);
  font-size: 0.9em;
  background-color: var(--color-surface);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
}

/* ============================================
   LAYOUT UTILITIES
   ============================================ */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.section {
  padding: var(--space-20) 0;
}

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

.section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(
    90deg,
    var(--color-primary),
    var(--color-secondary)
  );
  margin: var(--space-4) auto 0;
  border-radius: var(--radius-full);
}

/* Grid System */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}
.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* Flexbox Utilities */
.flex {
  display: flex;
}

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

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.flex-col {
  display: flex;
  flex-direction: column;
}

/* ============================================
   NAVIGATION BAR
   ============================================ */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: var(--color-background);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-4) 0;
  z-index: 1000;
  transition: all var(--transition-base);
  backdrop-filter: blur(10px);
  background-color: rgba(255, 255, 255, 0.9);
}

[data-theme="dark"] .navbar {
  background-color: rgba(10, 10, 10, 0.9);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

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

.nav-logo {
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-text);
  background: linear-gradient(
    135deg,
    var(--color-primary),
    var(--color-secondary)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  gap: var(--space-8);
  list-style: none;
  align-items: center;
}

.nav-link {
  color: var(--color-text-secondary);
  font-weight: 500;
  position: relative;
  padding: var(--space-2) 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(
    90deg,
    var(--color-primary),
    var(--color-secondary)
  );
  transition: width var(--transition-base);
}

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

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

/* Theme Toggle Button */
.theme-toggle {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-size: var(--text-lg);
}

.theme-toggle:hover {
  background: var(--color-surface-elevated);
  transform: rotate(20deg);
}

/* ============================================
   BUTTONS
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  text-decoration: none;
  font-family: var(--font-primary);
}

.btn-primary {
  background: linear-gradient(135deg, #6b8e23, #808000);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

.btn-secondary:hover {
  background: var(--color-surface-elevated);
  border-color: var(--color-primary);
}

/* ============================================
   CARDS
   ============================================ */

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

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

.card-title {
  font-size: var(--text-xl);
  font-weight: 700;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}

.card-text {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
}

.card-meta {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  display: flex;
  gap: var(--space-4);
  align-items: center;
}

/* ============================================
   FORMS
   ============================================ */

.form-group {
  margin-bottom: var(--space-5);
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}

.form-input,
.form-textarea {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  font-family: var(--font-primary);
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(107, 142, 35, 0.1);
}

[data-theme="dark"] .form-input:focus,
[data-theme="dark"] .form-textarea:focus {
  box-shadow: 0 0 0 3px rgba(245, 244, 232, 0.1);
}

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

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

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding-top: 80px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(
    circle at 50% 50%,
    var(--color-primary),
    transparent 70%
  );
  opacity: 0.05;
  z-index: -1;
}

.hero-content {
  max-width: 800px;
  animation: fadeInUp 0.8s ease-out;
}

.hero-title {
  font-size: clamp(2.5rem, 8vw, 4rem);
  margin-bottom: var(--space-6);
  background: linear-gradient(
    135deg,
    var(--color-primary),
    var(--color-secondary)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: var(--text-xl);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-8);
}

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

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

.footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: var(--space-12) 0 var(--space-6);
  margin-top: var(--space-20);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-8);
  margin-bottom: var(--space-8);
}

.footer-section h4 {
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: var(--space-2);
}

.footer-links a {
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

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

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

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

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

@media (max-width: 768px) {
  .nav-menu {
    gap: var(--space-4);
  }

  .section {
    padding: var(--space-12) 0;
  }

  .hero {
    padding-top: 100px;
  }

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

  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.text-center {
  text-align: center;
}
.text-muted {
  color: var(--color-text-muted);
}
.mb-4 {
  margin-bottom: var(--space-4);
}
.mb-6 {
  margin-bottom: var(--space-6);
}
.mb-8 {
  margin-bottom: var(--space-8);
}
.mt-4 {
  margin-top: var(--space-4);
}
.mt-6 {
  margin-top: var(--space-6);
}
.mt-8 {
  margin-top: var(--space-8);
}