/* Premium Utilitarian Minimalism - Black & White UI for Messaging Platform */

/* 1. CSS Reset & Base Styles */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

/* 2. Color Palette (Warm Monochrome + Spot Pastels) */
:root {
  /* Canvas / Background */
  --canvas: #FFFFFF; /* Pure White */
  --canvas-warm: #F7F6F3; /* Warm Bone/Off-White */

  /* Primary Surface (Cards) */
  --surface: #FFFFFF;
  --surface-alt: #F9F9F8;

  /* Structural Borders / Dividers */
  --border: #EAEAEA;
  --border-light: rgba(0,0,0,0.06);

  /* Text Colors */
  --text-primary: #111111; /* Off-black/charcoal (never absolute black) */
  --text-secondary: #787774; /* Muted gray */
  --text-muted: #999999;

  /* Accent Colors (Highly desaturated pastels) */
  --accent-red: #FDEBEC;
  --accent-red-text: #9F2F2D;
  --accent-blue: #E1F3FE;
  --accent-blue-text: #1F6C9F;
  --accent-green: #EDF3EC;
  --accent-green-text: #346538;
  --accent-yellow: #FBF3DB;
  --accent-yellow-text: #956400;

  /* 3. Typography Architecture */
  /* Primary Sans-Serif (Body, UI, Buttons) */
  --font-sans: 'SF Pro Display', 'Geist Sans', 'Helvetica Neue', 'Switzer', sans-serif;

  /* Editorial Serif (Hero Headings & Quotes) */
  --font-serif: 'Lyon Text', 'Newsreader', 'Playfair Display', 'Instrument Serif', serif;

  /* Monospace (Code, Keystrokes, Meta-data) */
  --font-mono: 'Geist Mono', 'SF Mono', 'JetBrains Mono', monospace;
}

/* 4. Base Styles */
body {
  font-family: var(--font-sans);
  background-color: var(--canvas);
  color: var(--text-primary);
  line-height: 1.6; /* Generous line-height for legibility */
  min-height: 100dvh; /* Prevents iOS Safari viewport issues */
  position: relative;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 5. Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--text-primary);
  margin-bottom: 1rem;
  line-height: 1.1; /* Tight line-height for headings */
  letter-spacing: -0.03em; /* Tight tracking */
}

h1 {
  font-size: 2.5rem;
}

h2 {
  font-size: 2rem;
}

h3 {
  font-size: 1.75rem;
}

h4 {
  font-size: 1.5rem;
}

h5 {
  font-size: 1.25rem;
}

h6 {
  font-size: 1rem;
}

p {
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

blockquote {
  font-family: var(--font-serif);
  font-style: italic;
  border-left: 3px solid var(--border);
  padding-left: 1.5rem;
  margin: 2rem 0;
  color: var(--text-secondary);
}

/* 6. Container & Layout */
.container {
  width: 100%;
  max-width: none;
  margin: 0;
  padding: 2rem; /* comfortable padding on all sides */
  text-align: left;
  box-sizing: border-box;
}

section {
  margin-bottom: 4rem; /* py-24 equivalent */
}

/* 7. Button Styles */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--text-primary); /* Solid background #111111 */
  color: var(--canvas); /* text #FFFFFF */
  border: none;
  border-radius: 6px; /* Slight border-radius */
  padding: 0.75rem 1.5rem;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 0.875rem;
  cursor: pointer;
  transition: background-color 0.2s ease, transform 0.1s ease;
  text-decoration: none;
}

.button:hover {
  background-color: #333333; /* Subtle color shift on hover */
  transform: translateY(-1px);
}

.button:active {
  transform: scale(0.98); /* Micro-scale on active */
}

.button:active {
  transform: scale(0.98); /* Micro-scale on active */
}

.button-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.button-secondary:hover {
  background-color: var(--canvas-warm);
}

/* 8. Form Elements */
input[type="text"],
input[type="password"],
input[type="email"],
textarea {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background-color: var(--canvas);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  transition: border-color 0.2s ease;
}

input[type="text"]:focus,
input[type="password"]:focus,
input[type="email"]:focus,
textarea:focus {
  outline: none;
  border-color: var(--text-primary);
  box-shadow: 0 0 0 2px rgba(0,0,0,0.1);
}

.input-error {
  border-color: var(--accent-red-text);
  background-color: var(--accent-red);
}

.error-state {
  border-color: var(--accent-red-text);
  background-color: var(--accent-red);
}

.error-text {
  color: var(--accent-red-text);
  font-size: 0.875rem;
  margin-top: 0.5rem;
}

/* Skeleton Loader */
.skeleton {
  background: linear-gradient(90deg, var(--canvas-warm) 25%, var(--surface-alt) 50%, var(--canvas-warm) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite ease-in-out;
  border-radius: 4px;
}

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

.skeleton-text {
  height: 1rem;
  margin-bottom: 0.5rem;
}

.skeleton-title {
  height: 2rem;
  margin-bottom: 1rem;
}

.skeleton-avatar {
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  margin-bottom: 1rem;
}

/* Focus Rings for Accessibility */
.focus-ring:focus-visible {
  outline: 2px solid var(--text-primary);
  outline-offset: 2px;
}

/* Enhanced Bento Grid with Asymmetrical Layouts */
.bento-grid {
  display: grid;
  gap: 1rem;
  margin-bottom: 2rem;
}

/* Asymmetrical layouts - example configurations */
.bento-grid-2-cols {
  grid-template-columns: repeat(2, 1fr);
}

.bento-grid-2-cols-primary {
  grid-template-columns: 2fr 1fr;
}

.bento-grid-2-cols-secondary {
  grid-template-columns: 1fr 2fr;
}

.bento-grid-2-cols .bento-card:nth-child(1),
.bento-grid-2-cols-primary .bento-card:nth-child(1),
.bento-grid-2-cols-secondary .bento-card:nth-child(1) {
  grid-row: span 2;
}

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

.bento-grid-3-cols .bento-card:nth-child(1) {
  grid-column: span 2;
  grid-row: span 2;
}

.bento-card {
  border: 1px solid var(--border);
  border-radius: 8px; /* Crisp border-radius */
  padding: 2rem; /* Generous internal padding */
  background-color: var(--surface);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
  position: relative;
  overflow: hidden;
}

.bento-card:hover {
  box-shadow: 0 2px 8px rgba(0,0,0,0.04); /* Ultra-subtle shift */
  transform: translateY(-2px);
}

.bento-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background-color: var(--accent-blue);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.bento-card:hover::before {
  opacity: 0.7;
}

.bento-card-header {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.bento-card-header::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent-blue);
}

.bento-card-content {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Ambient Background Motion (optional) */
.ambient-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: -1;
  opacity: 0.02;
}

.ambient-bg::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, var(--accent-blue) 0%, transparent 70%);
  transform: translate(-50%, -50%);
  animation: ambientFloat 20s ease-in-out infinite;
}

@keyframes ambientFloat {
  0%, 100% {
    transform: translate(-50%, -50%) translate(0, 0);
  }
  33% {
    transform: translate(-50%, -50%) translate(-30px, -30px);
  }
  66% {
    transform: translate(-50%, -50%) translate(30px, 20px);
  }
}

/* 9. Component Styles */

/* Fieldset (for grouping) */
fieldset {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 2rem;
  margin-bottom: 2rem;
  background-color: var(--surface);
}

legend {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.125rem;
  color: var(--text-primary);
  padding: 0 0.5rem;
  margin-bottom: 1rem;
  display: block;
}

/* Tables */
.table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 2rem;
  background-color: var(--surface);
}

.table th,
.table td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
}

/* Friends table: give more width to name column */
.table-friends th:first-child,
.table-friends td:first-child {
  width: 65%;
}

.table-friends th:last-child,
.table-friends td:last-child {
  width: 35%;
}

.table th {
  background-color: var(--canvas-warm);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
}

.table tr:last-child td {
  border-bottom: none;
}

.table tbody tr:hover {
  background-color: var(--canvas-warm);
}

/* 10. Bento Box Feature Grids */
.bento-grid {
  display: grid;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

/* Asymmetrical layouts - example configurations */
.bento-grid-2-cols {
  grid-template-columns: repeat(2, 1fr);
}

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

.bento-card {
  border: 1px solid var(--border);
  border-radius: 8px; /* Crisp border-radius */
  padding: 2rem; /* Generous internal padding */
  background-color: var(--surface);
  transition: box-shadow 0.3s ease;
}

.bento-card:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.04); /* Ultra-diffuse shadow */
}

.bento-card-header {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.bento-card-content {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 11. Tags & Status Badges */
.tag {
  display: inline-flex;
  align-items: center;
  background-color: var(--accent-blue);
  color: var(--accent-blue-text);
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px; /* Pill-shaped */
  margin: 0.25rem;
}

.tag-red {
  background-color: var(--accent-red);
  color: var(--accent-red-text);
}

.tag-green {
  background-color: var(--accent-green);
  color: var(--accent-green-text);
}

.tag-yellow {
  background-color: var(--accent-yellow);
  color: var(--accent-yellow-text);
}

/* 12. Keystroke Micro-UIs */
kbd {
  border: 1px solid var(--border);
  border-radius: 4px;
  background-color: var(--canvas-warm);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.2rem 0.4rem;
  margin: 0 0.1rem;
}

/* 13. Accordions (FAQ) */
.accordion-item {
  border-bottom: 1px solid var(--border);
  padding: 1.5rem 0;
}

.accordion-item:last-child {
  border-bottom: none;
}

.accordion-button {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  font-family: var(--font-serif);
  font-size: 1.125rem;
  color: var(--text-primary);
  cursor: pointer;
  padding: 0;
  width: 100%;
  text-align: left;
}

.accordion-button:hover {
  color: var(--text-secondary);
}

.accordion-icon {
  font-size: 0.75rem;
  transition: transform 0.2s ease;
}

.accordion-button[aria-expanded="true"] .accordion-icon {
  transform: rotate(45deg);
}

.accordion-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  color: var(--text-secondary);
  line-height: 1.6;
  font-size: 0.875rem;
}

.accordion-panel p {
  margin-bottom: 1rem;
}

/* 14. Utility Classes */
.text-center {
  text-align: center;
}

.text-right {
  text-align: right;
}

.text-primary {
  color: var(--text-primary);
}

.text-secondary {
  color: var(--text-secondary);
}

.text-muted {
  color: var(--text-muted);
}

.bg-surface {
  background-color: var(--surface);
}

.bg-surface-alt {
  background-color: var(--surface-alt);
}

.border {
  border: 1px solid var(--border);
}

.border-radius {
  border-radius: 8px;
}

.mb-2 {
  margin-bottom: 0.5rem;
}

.mb-4 {
  margin-bottom: 1rem;
}

.mb-6 {
  margin-bottom: 1.5rem;
}

.mb-8 {
  margin-bottom: 2rem;
}

/* Focus Rings for Accessibility */
.focus-ring:focus-visible {
  outline: 2px solid var(--text-primary);
  outline-offset: 2px;
}

/* Skip Link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--text-primary);
  color: var(--canvas);
  padding: 8px 12px;
  z-index: 100;
  transition: top 0.3s ease;
}

.skip-link:focus {
  top: 0;
}

/* Responsive adjustments */
@media (max-width: 640px) {
  .bento-grid {
    grid-template-columns: 1fr;
  }
  .bento-grid-2-cols-primary,
  .bento-grid-2-cols-secondary {
    grid-template-columns: 1fr;
  }
  .container {
    padding: 3rem 1.5rem;
  }
}

/* 15. Subtle Motion & Micro-Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  opacity: 0;
  animation: fadeInUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.fade-in-up-delay-0 {
  animation-delay: 0ms;
}

.fade-in-up-delay-1 {
  animation-delay: 80ms;
}

.fade-in-up-delay-2 {
  animation-delay: 160ms;
}

.fade-in-up-delay-3 {
  animation-delay: 240ms;
}

/* Hover states for cards */
.bento-card:hover,
fieldset:hover {
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
  transform: translateY(-1px);
}

/* 16. Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .fade-in-up {
    animation: none;
  }

  .bento-card:hover,
  .fieldset:hover {
    box-shadow: none;
  }
}

/* 17. Responsiveness */
@media (max-width: 640px) {
  .container {
    padding: 1.5rem;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  .bento-grid-2-cols,
  .bento-grid-2-cols-primary,
  .bento-grid-2-cols-secondary,
  .bento-grid-3-cols {
    grid-template-columns: 1fr;
  }
}