/* ========================================
   SpotMyBackup - Modern Responsive Design
   ======================================== */

/* CSS Variables - Design System */
:root {
  /* Colors */
  --bg-primary: #0a0a0a;
  --bg-secondary: #121212;
  --bg-card: rgba(30, 30, 30, 0.8);
  --bg-glass: rgba(255, 255, 255, 0.05);
  --spotify-green: #1DB954;
  --spotify-green-hover: #1ed760;
  --spotify-green-dark: #158a3d;
  --text-primary: #ffffff;
  --text-secondary: #b3b3b3;
  --text-muted: #727272;
  --border-color: rgba(255, 255, 255, 0.1);
  --shadow-color: rgba(0, 0, 0, 0.5);
  --glow-color: rgba(29, 185, 84, 0.3);

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

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 500px;

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: linear-gradient(135deg, var(--bg-primary) 0%, #1a1a2e 50%, var(--bg-primary) 100%);
  background-attachment: fixed;
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Animated Background Pattern */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image:
    radial-gradient(circle at 20% 80%, rgba(29, 185, 84, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(29, 185, 84, 0.05) 0%, transparent 50%);
  pointer-events: none;
  z-index: -1;
}

/* Container */
.container {
  width: 100%;
  max-width: 700px;
  margin: 0 auto;
  padding: var(--spacing-md);
}

/* Header / Heading */
.heading {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-md);
  box-shadow:
    0 8px 32px var(--shadow-color),
    0 0 0 1px rgba(255, 255, 255, 0.05);
  position: relative;
  overflow: hidden;
}

.heading::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(29, 185, 84, 0.5), transparent);
}

/* Logo */
.logo {
  max-width: 100px;
  height: auto;
  margin: 0 auto var(--spacing-sm);
  display: block;
}

/* Title Container */
.title-container {
  text-align: center;
  margin-bottom: var(--spacing-sm);
}

/* Heading centered content */
.heading {
  text-align: center;
}

/* Logo Title */
.title-bold {
  font-weight: 800;
  font-size: clamp(2rem, 5vw, 3rem);
  background: linear-gradient(135deg, var(--spotify-green) 0%, #1ed760 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.title-light {
  font-weight: 300;
  font-size: clamp(2rem, 5vw, 3rem);
  color: var(--text-secondary);
  letter-spacing: -0.02em;
}

.title-medium {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

/* Subtitle / Description */
#pnlLoggedOut span {
  display: block;
  color: var(--text-secondary);
  font-size: 1rem;
  margin: var(--spacing-md) 0;
  line-height: 1.7;
}

#pnlLoggedOut span b,
#pnlLoggedOut p b {
  color: var(--spotify-green);
  font-weight: 600;
}

/* Description paragraph */
.description {
  color: var(--text-secondary);
  font-size: 1rem;
  margin: var(--spacing-md) 0;
  line-height: 1.7;
}

/* Divider */
.divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color), transparent);
  margin: var(--spacing-lg) 0;
}

/* Center login button */
#pnlLoggedOut {
  text-align: center;
}

/* Primary Button */
.button-main {
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--bg-primary);
  background: linear-gradient(135deg, var(--spotify-green) 0%, var(--spotify-green-hover) 100%);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  padding: 1rem 2.5rem;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  transition:
    transform var(--transition-fast),
    box-shadow var(--transition-normal),
    background var(--transition-normal);
  box-shadow:
    0 4px 15px var(--glow-color),
    0 2px 4px rgba(0, 0, 0, 0.2);
  position: relative;
  overflow: hidden;
}

.button-main::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s ease;
}

.button-main:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow:
    0 8px 25px var(--glow-color),
    0 4px 8px rgba(0, 0, 0, 0.3);
}

.button-main:hover::before {
  left: 100%;
}

.button-main:active {
  transform: translateY(0) scale(0.98);
}

/* Remove old margin classes - handled by flexbox now */
.button-big,
.button-medium {
  margin: 0;
}

/* Action Panel - inside main container */
#pnlAction {
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
  padding: 0;
  margin: 0;
}

/* Secondary button style */
.button-secondary {
  background: transparent;
  color: var(--spotify-green);
  border: 2px solid var(--spotify-green);
  box-shadow: none;
}

.button-secondary:hover {
  background: rgba(29, 185, 84, 0.1);
  box-shadow: 0 4px 15px var(--glow-color);
}

/* Loading Account Panel */
#pnlLoadingAccount {
  text-align: center;
}

#pnlLoadingAccount .title-medium {
  color: var(--spotify-green);
}

#loadingPlaylists,
#loadingTracks {
  color: var(--text-secondary);
  font-size: 0.95rem;
  padding: var(--spacing-xs) 0;
}

#loadingTitle {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: var(--spacing-sm);
  padding: var(--spacing-sm);
  background: var(--bg-glass);
  border-radius: var(--radius-sm);
}

/* Import Panel */
#pnlImport,
#pnlUpload {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
}

#pnlFile {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  align-items: flex-start;
}

#pnlFile>div {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* File Input Styling */
input[type="file"] {
  font-family: inherit;
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding: var(--spacing-sm);
  background: var(--bg-glass);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color var(--transition-fast);
  width: 100%;
}

input[type="file"]:hover {
  border-color: var(--spotify-green);
}

input[type="file"]::file-selector-button {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--bg-primary);
  background: var(--spotify-green);
  border: none;
  border-radius: var(--radius-sm);
  padding: 0.5rem 1rem;
  margin-right: var(--spacing-sm);
  cursor: pointer;
  transition: background var(--transition-fast);
}

input[type="file"]::file-selector-button:hover {
  background: var(--spotify-green-hover);
}

/* Progress Bar */
.progress {
  width: 100%;
  padding: 0;
  margin-top: var(--spacing-md);
  background: var(--bg-glass);
  border-radius: var(--radius-full);
  overflow: hidden;
  height: 8px;
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--spotify-green) 0%, var(--spotify-green-hover) 100%);
  border-radius: var(--radius-full);
  transition: width 0.4s ease;
  position: relative;
}

.progress-bar::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255, 255, 255, 0.3) 50%, transparent 100%);
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }

  100% {
    transform: translateX(100%);
  }
}

/* Upload Panel */
#pnlUpload .title-medium {
  text-align: center;
  margin-bottom: var(--spacing-md);
}

#playlistStep,
#playlistTotal,
#trackStep,
#trackTotal {
  color: var(--spotify-green);
  font-weight: 600;
}

#globalStep {
  color: var(--text-muted);
  font-size: 0.9rem;
  text-align: center;
  margin-top: var(--spacing-sm);
}

/* Footer */
.footer {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  z-index: 100;
}

.footer .container {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-color);
  border-bottom: none;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-sm) var(--spacing-md);
  margin-bottom: 0;
}

.link {
  font-size: 0.85rem;
  padding: var(--spacing-xs) var(--spacing-sm);
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
  border-radius: var(--radius-sm);
}

.link:hover {
  color: var(--spotify-green);
}

/* GitHub Fork Ribbon */
body>a:first-child {
  opacity: 0.7;
  transition: opacity var(--transition-fast);
}

body>a:first-child:hover {
  opacity: 1;
}

/* Development Mode Panel Enhancement */
#devModePanel {
  border-radius: var(--radius-lg) !important;
  margin: var(--spacing-md) 0 !important;
}

/* ========================================
   Responsive Design
   ======================================== */

/* Tablet */
@media (max-width: 768px) {
  html {
    font-size: 15px;
  }

  .container {
    padding: var(--spacing-sm);
    margin-bottom: 80px;
    /* Space for footer */
  }

  .heading {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
  }

  .button-main {
    width: 100%;
    padding: 1rem 1.5rem;
  }

  #pnlAction {
    flex-direction: column;
  }

  #pnlAction>div {
    width: 100% !important;
  }

  /* Hide GitHub ribbon on tablet */
  body>a:first-child {
    display: none;
  }

  .footer .container {
    border-radius: 0;
  }
}

/* Mobile */
@media (max-width: 480px) {
  html {
    font-size: 14px;
  }

  .container {
    padding: var(--spacing-xs);
  }

  .heading {
    padding: var(--spacing-sm);
    border-radius: var(--radius-sm);
  }

  .title-bold,
  .title-light {
    font-size: 1.8rem;
  }

  #pnlLoggedOut span {
    font-size: 0.9rem;
  }

  .button-main {
    font-size: 0.85rem;
    padding: 0.875rem 1.25rem;
    letter-spacing: 1px;
  }

  #pnlImport,
  #pnlUpload {
    padding: var(--spacing-sm);
    border-radius: var(--radius-sm);
  }

  input[type="file"] {
    padding: var(--spacing-xs);
  }
}

/* Landscape phones */
@media (max-height: 500px) and (orientation: landscape) {
  .footer {
    position: relative;
  }

  .container {
    margin-bottom: 0;
  }
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.heading,
#pnlImport,
#pnlUpload {
  animation: fadeIn 0.5s ease;
}

/* Focus States for Accessibility */
.button-main:focus,
.link:focus,
input[type="file"]:focus {
  outline: 2px solid var(--spotify-green);
  outline-offset: 2px;
}

/* Print Styles */
@media print {
  body {
    background: white;
    color: black;
  }

  .footer,
  body>a:first-child {
    display: none;
  }
}