/* =========================================
   PROFESSIONAL DESIGN SYSTEM
   20+ Years UX/UI Best Practices
   ========================================= */

/* Color Variables - Professional Palette */
:root {
  /* Primary Colors */
  --brand-dark: #0f766e;
  --brand: #14b8a6;
  --brand-light: #ccfbf1;
  --accent: #2563eb;
  --accent-light: #dbeafe;

  /* Neutral Scale */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --bg-primary: #f8fafc;
  --bg-secondary: #f1f5f9;
  --bg-tertiary: #ffffff;
  
  /* Status Colors */
  --success: #16a34a;
  --warning: #ea580c;
  --info: #0284c7;
  --danger: #dc2626;

  /* Borders & Shadows */
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 6px rgba(15, 23, 42, 0.1);
  --shadow-lg: 0 10px 15px rgba(15, 23, 42, 0.15);
  --shadow-xl: 0 20px 25px rgba(15, 23, 42, 0.2);
  --shadow-focus: 0 0 0 3px rgba(20, 184, 166, 0.1);

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;

  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 18px;
  --radius-full: 999px;

  /* Typography */
  --font-sans: "Manrope", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: "Playfair Display", Georgia, serif;
  --font-mono: "Consolas", "Monaco", "Courier New", monospace;

  --line-height-tight: 1.2;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;

  /* Z-index */
  --z-sticky: 10;
  --z-modal: 100;
  --z-dropdown: 20;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-primary);
  line-height: var(--line-height-normal);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Background Animations */
.background-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(140deg, rgba(20, 184, 166, 0.06), transparent 60%);
  z-index: 1;
}

.ambient-light {
  position: fixed;
  pointer-events: none;
  z-index: 0;
  opacity: 0.4;
  mix-blend-mode: screen;
}

.ambient-light.top {
  top: -10%;
  left: 10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(20, 184, 166, 0.3), transparent);
  border-radius: 50%;
  filter: blur(60px);
}

.ambient-light.bottom {
  bottom: -10%;
  right: 5%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.2), transparent);
  border-radius: 50%;
  filter: blur(80px);
}

/* Header / Navigation */
.topbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  backdrop-filter: blur(12px);
  background: rgba(248, 250, 252, 0.92);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md) clamp(var(--spacing-md), 4vw, var(--spacing-xl));
  gap: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
}

.brand-wrap {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.brand-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--brand-dark), var(--accent));
  color: white;
  border-radius: var(--radius-lg);
  font-size: 1.25rem;
  box-shadow: 0 4px 12px rgba(20, 184, 166, 0.3);
}

.brand-content {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.kicker {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  font-weight: 600;
}

.brand-title {
  font-size: clamp(1rem, 2.5vw, 1.5rem);
  font-weight: 700;
  line-height: var(--line-height-tight);
}

.header-actions {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

.theme-toggle {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  background: var(--bg-tertiary);
  border-radius: var(--radius-lg);
  cursor: pointer;
  font-size: 1.1rem;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background: var(--bg-secondary);
  border-color: var(--brand);
  color: var(--brand-dark);
  transform: scale(1.05);
}

/* Main Container */
.container {
  width: min(1200px, 95%);
  margin: var(--spacing-lg) auto;
  position: relative;
  flex: 1;
}

/* Hero Section */
.hero-section {
  padding: clamp(var(--spacing-xl), 5vw, var(--spacing-2xl));
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-xl);
  animation: slideInUp 0.6s ease;
}

.hero-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: var(--line-height-tight);
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--text-primary), var(--brand-dark));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 70ch;
  line-height: var(--line-height-relaxed);
  margin-bottom: var(--spacing-lg);
}

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

.stat {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.stat-number {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--brand-dark);
}

.stat-label {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* Controls Section */
.controls-section {
  margin-bottom: var(--spacing-xl);
  animation: slideInUp 0.6s ease 100ms backwards;
}

.search-container {
  display: grid;
  gap: var(--spacing-md);
}

.search-wrap {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.search-wrap:focus-within {
  border-color: var(--brand);
  box-shadow: var(--shadow-focus);
}

.search-icon {
  color: var(--text-muted);
  margin-right: var(--spacing-md);
  font-size: 1.1rem;
}

#projectSearch {
  flex: 1;
  border: none;
  background: transparent;
  font: inherit;
  color: var(--text-primary);
  outline: none;
  font-size: 1rem;
}

#projectSearch::placeholder {
  color: var(--text-muted);
}

.controls-meta {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
  justify-content: space-between;
}

.badge {
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid var(--accent);
  border-radius: var(--radius-full);
  padding: var(--spacing-sm) var(--spacing-md);
  font-weight: 600;
  font-size: 0.9rem;
  white-space: nowrap;
}

.filter-toggle {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  background: var(--bg-tertiary);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 1rem;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
}

.filter-toggle:hover {
  border-color: var(--brand);
  color: var(--brand-dark);
  background: var(--bg-secondary);
}

/* Filter Panel */
.filter-panel {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  animation: slideDown 0.3s ease;
}

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-lg);
}

.filter-label {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  cursor: pointer;
  user-select: none;
}

.filter-label input {
  cursor: pointer;
  width: 18px;
  height: 18px;
  accent-color: var(--brand);
}

.filter-label span {
  color: var(--text-secondary);
  font-weight: 500;
}

/* Info Banner */
.info-banner {
  background: linear-gradient(135deg, rgba(20, 184, 166, 0.1), rgba(37, 99, 235, 0.05));
  border: 1px solid var(--brand-light);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  animation: slideInUp 0.6s ease 200ms backwards;
}

.info-icon {
  font-size: 1.5rem;
  color: var(--brand-dark);
  flex-shrink: 0;
}

.info-banner h3 {
  font-size: 1rem;
  margin: 0 0 var(--spacing-xs) 0;
  color: var(--brand-dark);
}

.info-banner p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* Category Section */
.category-section {
  margin-bottom: var(--spacing-xl);
}

.section-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.category-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
}

.category-btn {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-lg);
  cursor: pointer;
  font-weight: 600;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.category-btn:hover {
  border-color: var(--brand);
  color: var(--brand-dark);
  background: var(--brand-light);
}

.category-btn.active {
  background: linear-gradient(135deg, var(--brand-dark), var(--brand));
  color: white;
  border-color: var(--brand);
  box-shadow: 0 4px 12px rgba(20, 184, 166, 0.3);
}

.category-count {
  background: rgba(0, 0, 0, 0.1);
  padding: 0 var(--spacing-xs);
  border-radius: 4px;
  font-size: 0.85rem;
}

.category-btn.active .category-count {
  background: rgba(255, 255, 255, 0.3);
}

/* Projects Grid */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.card {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
  opacity: 0;
  animation: cardSlideIn 0.5s ease forwards;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-dark), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}

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

.card:hover::before {
  transform: scaleX(1);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--spacing-md);
}

.card-type-badge {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  background: var(--accent-light);
  color: var(--accent);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
  white-space: nowrap;
}

.card-type-icon {
  font-size: 0.9rem;
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin: 0;
  color: var(--text-primary);
}

.card-path {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  background: var(--bg-secondary);
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  margin: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.card-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin: 0;
  line-height: var(--line-height-normal);
  flex-grow: 1;
}

.card-meta {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.category-tag {
  display: inline-block;
  background: var(--brand-light);
  color: var(--brand-dark);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
}

.card-actions {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-fast);
  white-space: nowrap;
  text-align: center;
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-dark), var(--brand));
  color: white;
  box-shadow: 0 4px 12px rgba(15, 118, 110, 0.3);
  flex: 1;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(15, 118, 110, 0.4);
}

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

.btn-secondary:hover {
  background: var(--brand-light);
  border-color: var(--brand);
  color: var(--brand-dark);
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: var(--spacing-2xl);
  color: var(--text-muted);
}

.empty-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
  opacity: 0.6;
}

.empty-state h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  color: var(--text-secondary);
}

.empty-state p {
  margin: 0;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  margin-top: auto;
  padding: var(--spacing-xl) var(--spacing-md);
}

.footer-content {
  width: min(1200px, 95%);
  margin: 0 auto;
  text-align: center;
}

.footer-content p {
  margin: var(--spacing-sm) 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.designer-note {
  font-style: italic;
  margin-top: var(--spacing-md);
}

/* Animations */
@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

/* Stagger animation for cards */
@for $i from 1 through 12 {
  .card:nth-child(#{$i}) {
    animation-delay: #{$i * 50ms};
  }
}

/* Responsive Design */
@media (max-width: 768px) {
  .topbar {
    flex-wrap: wrap;
  }

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

  .controls-meta {
    flex-direction: column;
    width: 100%;
  }

  .category-tabs {
    gap: var(--spacing-sm);
  }

  .grid {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-md);
  }

  .card {
    padding: var(--spacing-md);
  }

  .card-actions {
    flex-wrap: wrap;
  }

  .btn-primary {
    min-width: auto;
  }
}

@media (max-width: 640px) {
  :root {
    --spacing-xl: 1.5rem;
    --spacing-2xl: 2rem;
  }

  .topbar {
    padding: var(--spacing-md);
  }

  .hero-section {
    padding: var(--spacing-lg);
  }

  .hero-title {
    font-size: 1.5rem;
  }

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

  .category-tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    gap: var(--spacing-sm);
  }

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

  .card-header {
    flex-direction: column;
  }

  .card-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}

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

@media (prefers-color-scheme: dark) {
  :root {
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #1e293b;
    --border: #334155;
    --border-light: #475569;
  }

  .topbar {
    background: rgba(15, 23, 42, 0.92);
  }

  .search-wrap,
  .filter-toggle,
  .theme-toggle {
    background: var(--bg-secondary);
  }
}