/* Modern Design System for PresHost */
:root {
  --font-heading: 'Outfit', 'Inter', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;

  /* Color Palette (Deep space / Dark mode focus) */
  --bg-dark: #0a0b10;
  --bg-card: rgba(20, 22, 33, 0.65);
  --bg-card-hover: rgba(28, 31, 46, 0.85);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(139, 92, 246, 0.3);
  
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-inverse: #090a0f;

  --accent-primary: #8b5cf6; /* Violet */
  --accent-secondary: #3b82f6; /* Blue */
  --accent-glow: rgba(139, 92, 246, 0.15);
  
  --success: #10b981;
  
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --border-radius-lg: 16px;
  --border-radius-md: 10px;
  --border-radius-sm: 6px;
}

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

body {
  background-color: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-body);
  line-height: 1.5;
  overflow-x: hidden;
  min-height: 100vh;
}

/* Ambient glow backgrounds */
.glow-bg {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.glow-1 {
  position: absolute;
  top: -10%;
  right: 15%;
  width: 40vw;
  height: 40vw;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.18) 0%, transparent 70%);
  filter: blur(80px);
  animation: float-slow 20s infinite ease-in-out alternate;
}

.glow-2 {
  position: absolute;
  bottom: 5%;
  left: 10%;
  width: 35vw;
  height: 35vw;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.15) 0%, transparent 70%);
  filter: blur(80px);
  animation: float-slow 25s infinite ease-in-out alternate-reverse;
}

@keyframes float-slow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(3vw, 5vh) scale(1.1); }
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Header */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 3rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.brand {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.logo {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  width: 46px;
  height: 46px;
  border-radius: var(--border-radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 20px rgba(139, 92, 246, 0.3);
}

.logo-icon {
  color: #fff;
  width: 24px;
  height: 24px;
}

.brand-text h1 {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  background: linear-gradient(135deg, #fff 40%, #c084fc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.brand-text p {
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.2rem;
  border-radius: var(--border-radius-md);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  color: #fff;
  border: none;
  box-shadow: 0 4px 15px rgba(139, 92, 246, 0.2);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(139, 92, 246, 0.35);
  background: linear-gradient(135deg, #996bf8, #4f8ff7);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
}

/* Controls section: Search and Filters */
.controls-section {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 2.5rem;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  padding: 1.5rem;
  border-radius: var(--border-radius-lg);
  backdrop-filter: blur(10px);
}

.search-box {
  position: relative;
  width: 100%;
}

.search-icon {
  position: absolute;
  left: 1.2rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  width: 20px;
  height: 20px;
  pointer-events: none;
}

#search-input {
  width: 100%;
  padding: 1rem 1rem 1rem 3.2rem;
  background: rgba(10, 11, 16, 0.6);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  color: var(--text-main);
  font-family: var(--font-body);
  font-size: 1rem;
  outline: none;
  transition: var(--transition-smooth);
}

#search-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px var(--accent-glow);
  background: rgba(10, 11, 16, 0.8);
}

.filters-container {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.filter-label {
  color: var(--text-muted);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.categories-list {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.category-pill {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  padding: 0.4rem 1rem;
  border-radius: 100px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.category-pill:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-main);
}

.category-pill.active {
  background: var(--accent-primary);
  color: #fff;
  border-color: var(--accent-primary);
  box-shadow: 0 4px 10px rgba(139, 92, 246, 0.2);
}

/* Presentations Grid Section */
.grid-section {
  flex-grow: 1;
  margin-bottom: 3rem;
}

.grid-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.grid-header h2 {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  font-weight: 600;
}

.badge {
  background: rgba(139, 92, 246, 0.15);
  color: #c084fc;
  border: 1px solid rgba(139, 92, 246, 0.2);
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
}

.presentations-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
  min-height: 200px;
}

/* Presentation Card */
.presentation-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 1.5rem;
  backdrop-filter: blur(10px);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.presentation-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition-smooth);
}

.presentation-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.3), 0 0 15px var(--accent-glow);
}

.presentation-card:hover::before {
  opacity: 1;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.card-category {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 700;
  color: var(--accent-primary);
}

.card-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.card-body h3 {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  line-height: 1.3;
}

.card-body p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 1.2rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  height: 2.7rem;
}

.card-tags {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.card-tag {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-muted);
  font-size: 0.75rem;
  padding: 0.15rem 0.5rem;
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--border-color);
}

.card-actions {
  display: flex;
  gap: 0.8rem;
  margin-top: auto;
}

.card-actions .btn {
  flex: 1;
  justify-content: center;
  font-size: 0.85rem;
  padding: 0.5rem 1rem;
}

/* Loader & Empty states */
.loader-container {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem;
  text-align: center;
  color: var(--text-muted);
}

.loader {
  border: 3px solid rgba(255, 255, 255, 0.05);
  border-top: 3px solid var(--accent-primary);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 1s linear infinite;
  margin-bottom: 1rem;
}

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

.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 4rem 2rem;
  border: 1px dashed var(--border-color);
  border-radius: var(--border-radius-lg);
  background: rgba(255, 255, 255, 0.01);
}

.empty-state i {
  color: var(--text-muted);
  width: 48px;
  height: 48px;
  margin-bottom: 1rem;
  opacity: 0.5;
}

.empty-state h3 {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

.empty-state p {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* How to add card info */
.info-section {
  margin-bottom: 3rem;
}

.info-card {
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.06), rgba(59, 130, 246, 0.04));
  border: 1px solid rgba(139, 92, 246, 0.15);
  border-radius: var(--border-radius-lg);
  padding: 1.5rem;
  display: flex;
  gap: 1.2rem;
  align-items: flex-start;
  backdrop-filter: blur(10px);
}

.info-icon {
  background: rgba(139, 92, 246, 0.15);
  color: var(--accent-primary);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.info-icon i {
  width: 20px;
  height: 20px;
}

.info-content h3 {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
}

.info-content p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

.info-content code {
  background: rgba(255, 255, 255, 0.08);
  padding: 0.1rem 0.3rem;
  border-radius: var(--border-radius-sm);
  font-family: monospace;
  font-size: 0.85rem;
  color: #e9d5ff;
}

/* Footer */
.footer {
  text-align: center;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.8rem;
}

/* Responsiveness */
@media (max-width: 768px) {
  .header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 2rem;
  }
  
  .header-actions {
    width: 100%;
  }
  
  .header-actions .btn {
    width: 100%;
    justify-content: center;
  }
  
  .controls-section {
    padding: 1rem;
  }
  
  .filters-container {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.6rem;
  }
  
  .presentations-grid {
    grid-template-columns: 1fr;
  }
  
  .info-card {
    flex-direction: column;
    gap: 0.8rem;
  }
}