/* ==========================================================================
   Sahil's Notes - Main Stylesheet
   Optimized for performance - no external dependencies
   ========================================================================== */

/* CSS Variables for theming */
:root {
  --bg-primary: #f3f4f6;
  --bg-secondary: #ffffff;
  --bg-tertiary: #e5e7eb;
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #9ca3af;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  --header-bg: rgba(255,255,255,0.85);
  --footer-bg: #1f2937;
  --footer-text: #9ca3af;
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
}

[data-theme="dark"] {
  --bg-primary: #111827;
  --bg-secondary: #1f2937;
  --bg-tertiary: #374151;
  --text-primary: #f9fafb;
  --text-secondary: #d1d5db;
  --text-muted: #6b7280;
  --header-bg: rgba(31,41,55,0.9);
  --footer-bg: #0f172a;
  --shadow: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.3);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  letter-spacing: -0.01em;
  transition: background var(--transition-normal), color var(--transition-normal);
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--accent-hover); }

/* Typography */
h1, h2, h3, h4 { line-height: 1.3; font-weight: 600; color: var(--text-primary); }
h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.375rem; }
p { color: var(--text-secondary); font-size: 1.0625rem; }

/* Layout */
.container { width: 100%; max-width: 1600px; margin: 0 auto; padding: 0 1.5rem; }
@media (min-width: 640px) { .container { padding: 0 2.5rem; } }
@media (min-width: 1024px) { .container { padding: 0 4rem; } }
@media (min-width: 1400px) { .container { padding: 0 5rem; } }

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@keyframes fadeInScale {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}

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

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

@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
}

/* Animations - desktop only for performance */
@media (min-width: 768px) {
  .fade-in { animation: fadeIn 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards; }
  .fade-in-up { animation: fadeInUp 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards; }
  .fade-in-scale { animation: fadeInScale 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards; }
  .slide-in-right { animation: slideInRight 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards; }
  .stagger-1 { animation-delay: 0.05s; }
  .stagger-2 { animation-delay: 0.1s; }
  .stagger-3 { animation-delay: 0.15s; }
  .stagger-4 { animation-delay: 0.2s; }
  .stagger-5 { animation-delay: 0.25s; }
  .stagger-6 { animation-delay: 0.3s; }
  main { animation: fadeInUp 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards; }
}

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

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-secondary) 50%, var(--bg-tertiary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: 0.375rem;
}

.skeleton-text { height: 1rem; margin-bottom: 0.5rem; }
.skeleton-text:last-child { width: 60%; }
.skeleton-title { height: 1.5rem; width: 70%; margin-bottom: 0.75rem; }
.skeleton-image { width: 100%; padding-top: 56.25%; /* 16:9 */ }
.skeleton-avatar { width: 3rem; height: 3rem; border-radius: 50%; }

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  box-shadow: var(--shadow);
}
@media (min-width: 768px) {
  .header {
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
}
@media (min-width: 768px) {
  .header-inner { padding: 1rem 0; }
}

.logo { display: flex; align-items: center; gap: 0.75rem; }
.logo img { width: 2.5rem; height: 2.5rem; border-radius: 50%; }
.logo-text h1 { font-size: 1.125rem; font-weight: 600; }
.logo-text p { font-size: 0.875rem; color: var(--text-muted); }

.nav { display: none; gap: 1.5rem; align-items: center; }
@media (min-width: 768px) { .nav { display: flex; } }

.menu-toggle { display: flex; margin-left: auto; }
@media (min-width: 768px) { .menu-toggle { display: none; } }

.theme-label { margin-left: 0.5rem; font-size: 0.875rem; color: var(--text-secondary); }

.nav a {
  color: var(--text-secondary);
  font-weight: 500;
  padding: 0.5rem 0;
  position: relative;
}
.nav a:hover { color: var(--text-primary); }
.nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--transition-fast);
}
.nav a:hover::after { width: 100%; }

/* Dark mode toggle */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 0.5rem;
  color: var(--text-secondary);
  transition: background var(--transition-fast), color var(--transition-fast);
}
.theme-toggle:hover { background: var(--bg-tertiary); color: var(--text-primary); }
.theme-toggle svg { width: 1.25rem; height: 1.25rem; }

/* Language switcher */
.lang-switch {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}
.lang-switch:hover {
  color: var(--primary);
}

/* Mobile menu */
.menu-toggle {
  display: flex;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text-secondary);
  transition: transform 0.2s ease, color 0.2s ease;
}
.menu-toggle:hover { color: var(--text-primary); }
.menu-toggle:active { transform: scale(0.9); }
@media (min-width: 768px) { .menu-toggle { display: none; } }
.menu-toggle svg { width: 1.5rem; height: 1.5rem; }

.mobile-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--bg-secondary);
  box-shadow: var(--shadow-lg);
  padding: 0.5rem 1rem 1rem;
}
.mobile-menu.active {
  display: block;
  animation: fadeInUp 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards;
}
.mobile-menu a, .mobile-menu button {
  display: flex;
  align-items: center;
  padding: 0.875rem 0;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--bg-tertiary);
  transition: color 0.2s ease, padding-left 0.2s ease;
}
.mobile-menu a:hover, .mobile-menu button:hover {
  color: var(--accent);
  padding-left: 0.5rem;
}
.mobile-menu a:last-of-type { border-bottom: none; }

/* Hero/Banner */
.hero {
  padding: 4rem 1rem;
  text-align: center;
  background-size: cover;
  background-position: center;
  position: relative;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(255,255,255,0.7), rgba(255,255,255,0.9));
}
[data-theme="dark"] .hero::before {
  background: linear-gradient(to bottom, rgba(17,24,39,0.7), rgba(17,24,39,0.9));
}
.hero-content { position: relative; z-index: 1; }
.hero h2 { font-size: 2.5rem; font-weight: 800; margin-bottom: 0.5rem; }
@media (min-width: 640px) { .hero h2 { font-size: 3rem; } }

/* Cards */
.card {
  background: var(--bg-secondary);
  border-radius: 0.75rem;
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
  cursor: pointer;
  border: 1px solid transparent;
  position: relative;
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(59, 130, 246, 0.15), 0 8px 16px rgba(0, 0, 0, 0.1);
  border-color: rgba(59, 130, 246, 0.3);
}
[data-theme="dark"] .card:hover {
  box-shadow: 0 20px 40px rgba(96, 165, 250, 0.2), 0 8px 16px rgba(0, 0, 0, 0.3);
  border-color: rgba(96, 165, 250, 0.4);
}
.card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 0.75rem;
  opacity: 0;
  transition: opacity 0.25s ease;
  pointer-events: none;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.05) 0%, transparent 50%);
}
.card:hover::after { opacity: 1; }
a.card {
  display: block;
  text-decoration: none;
  color: inherit;
}
a.card:hover { color: inherit; }
.card-image {
  width: 100%;
  height: 14rem;
  object-fit: cover;
  transition: transform 0.3s ease;
}
.card:hover .card-image { transform: scale(1.03); }
.card-body { padding: 1.5rem; position: relative; z-index: 1; }
.card-title { margin-bottom: 0.5rem; transition: color 0.2s ease; font-size: 1.25rem; }
.card:hover .card-title { color: var(--accent); }
.card-text { font-size: 1rem; margin-bottom: 0.75rem; }
.card-link {
  display: inline-flex;
  align-items: center;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  transition: gap 0.2s ease;
  gap: 0.25rem;
}
.card:hover .card-link { gap: 0.5rem; }

/* Reading time badge */
.reading-time {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}
.reading-time svg { width: 0.875rem; height: 0.875rem; }

/* Grid layouts */
.grid { display: grid; gap: 1.5rem; }
.grid-2 { grid-template-columns: 1fr; }
.grid-3 { grid-template-columns: 1fr; }
@media (min-width: 640px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1024px) {
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
}

/* Two column layout */
.layout-2col { display: flex; flex-direction: column; gap: 3rem; }
@media (min-width: 768px) {
  .layout-2col { flex-direction: row; gap: 3rem; }
  .layout-2col .col-main { flex: 2.5; }
  .layout-2col .col-side { flex: 1; }
}
@media (min-width: 1200px) {
  .layout-2col { gap: 4rem; }
  .layout-2col .col-main { flex: 3; }
}

/* Gallery */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}
@media (min-width: 640px) { .gallery-grid { grid-template-columns: repeat(3, 1fr); gap: 1.5rem; } }
@media (min-width: 1024px) { .gallery-grid { grid-template-columns: repeat(4, 1fr); gap: 1.5rem; } }
@media (min-width: 1400px) { .gallery-grid { grid-template-columns: repeat(5, 1fr); } }

.gallery-item {
  position: relative;
  border-radius: 0.75rem;
  overflow: hidden;
  cursor: pointer;
  aspect-ratio: 1;
  box-shadow: var(--shadow);
  transition: transform 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94),
              box-shadow 0.3s ease;
}
.gallery-item:hover {
  transform: translateY(-5px) scale(1.02);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}
[data-theme="dark"] .gallery-item:hover {
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
}
.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.gallery-item:hover img { transform: scale(1.1); }
.gallery-item-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 1rem 0.75rem;
  background: linear-gradient(transparent, rgba(0,0,0,0.8));
  color: white;
  font-size: 0.8rem;
  text-align: center;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}
.gallery-item:hover .gallery-item-overlay {
  opacity: 1;
  transform: translateY(0);
}

/* Lightbox */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(0,0,0,0);
  display: none;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  padding: 1rem;
  backdrop-filter: blur(0);
  transition: background 0.3s ease, backdrop-filter 0.3s ease;
}
.lightbox.active {
  display: flex;
  background: rgba(0,0,0,0.92);
  backdrop-filter: blur(10px);
}
.lightbox-content {
  position: relative;
  max-width: 90vw;
  max-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.9) translateY(20px);
  transition: opacity 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94),
              transform 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.lightbox.active .lightbox-content {
  opacity: 1;
  transform: scale(1) translateY(0);
}
.lightbox img {
  max-width: 100%;
  max-height: 80vh;
  object-fit: contain;
  border-radius: 0.5rem;
  box-shadow: 0 25px 80px rgba(0,0,0,0.5);
  transition: transform 0.3s ease;
}
.lightbox img.switching {
  opacity: 0;
  transform: scale(0.95);
}
.lightbox-title {
  color: white;
  margin-top: 1.5rem;
  font-size: 0.9rem;
  text-align: center;
  background: rgba(255,255,255,0.1);
  padding: 0.75rem 1.5rem;
  border-radius: 2rem;
  backdrop-filter: blur(10px);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.3s ease 0.1s, transform 0.3s ease 0.1s;
}
.lightbox.active .lightbox-title {
  opacity: 1;
  transform: translateY(0);
}
.lightbox-close {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  background: rgba(255,255,255,0.1);
  border: none;
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.75rem;
  line-height: 1;
  border-radius: 50%;
  width: 3rem;
  height: 3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.8);
  transition: opacity 0.3s ease, transform 0.3s ease, background 0.2s ease;
}
.lightbox.active .lightbox-close {
  opacity: 0.8;
  transform: scale(1);
}
.lightbox-close:hover {
  opacity: 1;
  background: rgba(255,255,255,0.2);
  transform: scale(1.1);
}
.lightbox-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%) scale(0.9);
  background: rgba(255,255,255,0.1);
  border: none;
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 1rem;
  opacity: 0;
  transition: opacity 0.3s ease, transform 0.3s ease, background 0.2s ease;
  border-radius: 50%;
  width: 3.5rem;
  height: 3.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(10px);
}
.lightbox.active .lightbox-nav {
  opacity: 0.7;
  transform: translateY(-50%) scale(1);
}
.lightbox-nav:hover {
  opacity: 1;
  background: rgba(255,255,255,0.2);
  transform: translateY(-50%) scale(1.1);
}
.lightbox-prev { left: 1.5rem; }
.lightbox-next { right: 1.5rem; }

/* Image counter */
.lightbox-counter {
  position: absolute;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  color: rgba(255,255,255,0.6);
  font-size: 0.8rem;
  opacity: 0;
  transition: opacity 0.3s ease 0.2s;
}
.lightbox.active .lightbox-counter { opacity: 1; }

/* Search */
.search-box {
  position: relative;
  margin-bottom: 1.5rem;
}
.search-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 2.75rem;
  border: 1px solid var(--bg-tertiary);
  border-radius: 0.5rem;
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-size: 1rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.search-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.1);
}
.search-input::placeholder { color: var(--text-muted); }
.search-icon {
  position: absolute;
  left: 0.875rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  pointer-events: none;
}
.search-icon svg { width: 1.25rem; height: 1.25rem; }

/* Footer */
.footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 2rem 0;
  text-align: center;
}
.footer p { font-size: 0.875rem; color: var(--footer-text); }
.footer p:last-child { font-size: 0.75rem; margin-top: 0.25rem; }

/* Single post */
.post-single {
  background: var(--bg-secondary);
  border-radius: 0.5rem;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.post-single img { width: 100%; }
.post-single-body { padding: 2rem; }
.post-single h1 { font-size: 1.75rem; margin-bottom: 1rem; }
@media (min-width: 640px) { .post-single h1 { font-size: 2rem; } }
.post-single-content { line-height: 1.8; }
.post-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 1.5rem;
}

/* Featured post */
.featured-post {
  display: block;
  background: var(--bg-secondary);
  border-radius: 0.75rem;
  box-shadow: var(--shadow);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  border: 1px solid transparent;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
a.featured-post:hover {
  color: inherit;
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(59, 130, 246, 0.15), 0 8px 16px rgba(0, 0, 0, 0.1);
  border-color: rgba(59, 130, 246, 0.3);
}
[data-theme="dark"] a.featured-post:hover {
  box-shadow: 0 20px 40px rgba(96, 165, 250, 0.2), 0 8px 16px rgba(0, 0, 0, 0.3);
  border-color: rgba(96, 165, 250, 0.4);
}
.featured-post img {
  width: 100%;
  transition: transform 0.3s ease;
}
.featured-post:hover img { transform: scale(1.02); }
.featured-post-body { padding: 2rem; }
.featured-post-body h3 { font-size: 1.5rem; }
.featured-post-body p { font-size: 1.0625rem; }
.featured-post:hover .card-title { color: var(--accent); }

/* Sidebar */
.sidebar-section { margin-bottom: 2.5rem; }
.sidebar-section h2 { margin-bottom: 1.25rem; font-size: 1.375rem; }
.sidebar-post {
  display: block;
  background: var(--bg-secondary);
  border-radius: 0.5rem;
  box-shadow: var(--shadow);
  padding: 1rem;
  margin-bottom: 1rem;
  text-decoration: none;
  color: inherit;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
a.sidebar-post:hover {
  color: inherit;
  transform: translateY(-3px);
  box-shadow: 0 10px 25px rgba(59, 130, 246, 0.12), 0 4px 10px rgba(0, 0, 0, 0.08);
  border-color: rgba(59, 130, 246, 0.25);
}
[data-theme="dark"] a.sidebar-post:hover {
  box-shadow: 0 10px 25px rgba(96, 165, 250, 0.15), 0 4px 10px rgba(0, 0, 0, 0.2);
  border-color: rgba(96, 165, 250, 0.3);
}
.sidebar-post img {
  width: 100%;
  height: 8rem;
  object-fit: cover;
  border-radius: 0.375rem;
  margin-bottom: 0.75rem;
  transition: transform 0.25s ease;
}
.sidebar-post:hover img { transform: scale(1.02); }
.sidebar-post h4 { font-size: 1rem; margin-bottom: 0.5rem; transition: color 0.2s ease; }
.sidebar-post:hover h4 { color: var(--accent); }
.sidebar-post p { font-size: 0.875rem; margin-bottom: 0.5rem; }

/* 404 page */
.error-page {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
}
.error-page h1 { font-size: 6rem; font-weight: 800; color: var(--accent); margin-bottom: 1rem; }
.error-page h2 { margin-bottom: 1rem; }
.error-page p { margin-bottom: 2rem; max-width: 400px; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.75rem;
  border-radius: 0.5rem;
  font-weight: 500;
  text-align: center;
  cursor: pointer;
  border: none;
  position: relative;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}
.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 50%);
  opacity: 0;
  transition: opacity 0.2s ease;
}
.btn:hover::before { opacity: 1; }
.btn:active { transform: scale(0.98); }
.btn-primary {
  background: var(--accent);
  color: white;
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}
.btn-primary:hover {
  background: var(--accent-hover);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}
.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}
.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

/* Utility classes */
.text-center { text-align: center; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.py-2 { padding-top: 1rem; padding-bottom: 1rem; }
.py-4 { padding-top: 2rem; padding-bottom: 2rem; }
.hidden { display: none !important; }

/* Typing cursor */
.typing-cursor::after {
  content: '|';
  animation: pulse 1s infinite;
}

/* Link styles */
.link { color: var(--accent); }
.link:hover { text-decoration: underline; }
.link-green { color: #22c55e; }

/* No results */
.no-results {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-muted);
}

/* Toast notification */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg-secondary);
  color: var(--text-primary);
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  box-shadow: var(--shadow-lg);
  z-index: 300;
  animation: fadeIn 0.3s ease-out;
}

/* Image blur-up loading effect */
.img-blur-wrapper {
  position: relative;
  overflow: hidden;
  background: var(--bg-tertiary);
}
.img-blur-wrapper img {
  transition: filter 0.4s ease, opacity 0.4s ease;
}
.img-blur-wrapper img.loading {
  filter: blur(20px);
  opacity: 0.6;
}
.img-blur-wrapper img.loaded {
  filter: blur(0);
  opacity: 1;
}

/* Gallery search */
.gallery-search,
.search-box {
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}
.search-results-count {
  text-align: center;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

/* ==========================================================================
   Takehara, Hiroshima - Topographic Background
   Stylized coastline of Seto Inland Sea area
   ========================================================================== */

.takehara-topo {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: -1;
  opacity: 0.35;
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
  background-image: url("../images/takehara-topo.svg");
}

[data-theme="dark"] .takehara-topo {
  opacity: 0.25;
  filter: invert(0.85) hue-rotate(180deg);
}