/* CSS Reset and CSS Variables */
:root {
  --bg-primary: hsl(230, 30%, 6%);
  --bg-secondary: hsl(230, 25%, 10%);
  --card-bg: rgba(20, 20, 35, 0.45);
  --card-border: rgba(255, 255, 255, 0.07);
  --card-border-focus: rgba(138, 43, 226, 0.4);
  
  --text-primary: hsl(210, 20%, 98%);
  --text-secondary: hsl(220, 15%, 72%);
  --text-muted: hsl(220, 10%, 50%);
  
  --primary-glow: linear-gradient(135deg, hsl(263, 85%, 65%), hsl(200, 95%, 55%));
  
  --color-purple: hsl(263, 85%, 60%);
  --color-purple-glow: rgba(138, 43, 226, 0.35);
  --color-cyan: hsl(190, 95%, 50%);
  --color-cyan-glow: rgba(0, 206, 209, 0.3);
  --color-success: hsl(145, 75%, 45%);
  --color-success-glow: rgba(46, 204, 113, 0.2);
  --color-error: hsl(355, 80%, 55%);
  --color-error-glow: rgba(231, 76, 60, 0.2);

  --font-family: 'Rubik', 'Outfit', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --border-radius-lg: 24px;
  --border-radius-md: 16px;
  --border-radius-sm: 8px;
}

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow-x: hidden;
  position: relative;
}

/* Background Glow Effects */
.bg-glow {
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  filter: blur(120px);
  z-index: -1;
  opacity: 0.45;
  pointer-events: none;
  animation: glow-float 20s infinite alternate ease-in-out;
}

.bg-glow-1 {
  background: radial-gradient(circle, var(--color-purple), transparent 70%);
  top: -10%;
  right: -10%;
}

.bg-glow-2 {
  background: radial-gradient(circle, var(--color-cyan), transparent 70%);
  bottom: -15%;
  left: -10%;
  animation-delay: -5s;
}

@keyframes glow-float {
  0% {
    transform: translate(0, 0) scale(1);
  }
  100% {
    transform: translate(-50px, 50px) scale(1.15);
  }
}

/* App Container Layout */
.app-container {
  width: 100%;
  max-width: 600px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 32px;
  z-index: 10;
}

/* Header */
.app-header {
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.logo-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.logo-icon {
  width: 38px;
  height: 38px;
  color: var(--color-cyan);
  filter: drop-shadow(0 0 10px var(--color-cyan-glow));
}

.app-header h1 {
  font-size: 2.2rem;
  font-weight: 800;
  font-family: 'Outfit', sans-serif;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #fff 30%, var(--text-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.tagline {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 480px;
  margin: 0 auto;
}

/* Main Card Glassmorphic container */
.main-card {
  background: var(--card-bg);
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-lg);
  padding: 36px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3), 
              inset 0 1px 0 rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
  transition: var(--transition-smooth);
}

/* Connection Status Badge */
.status-badge {
  position: absolute;
  top: 20px;
  left: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 500;
  border: 1px solid transparent;
  transition: var(--transition-smooth);
}

.status-badge.disconnected {
  background: rgba(231, 76, 60, 0.1);
  border-color: rgba(231, 76, 60, 0.2);
  color: var(--color-error);
}

.status-badge.connecting {
  background: rgba(243, 156, 18, 0.1);
  border-color: rgba(243, 156, 18, 0.2);
  color: hsl(40, 95%, 55%);
}

.status-badge.connected {
  background: rgba(46, 204, 113, 0.1);
  border-color: rgba(46, 204, 113, 0.2);
  color: var(--color-success);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: currentColor;
}

.status-badge.connecting .status-dot {
  animation: pulse 1.5s infinite ease-in-out;
}

@keyframes pulse {
  0%, 100% { opacity: 0.4; transform: scale(0.9); }
  50% { opacity: 1; transform: scale(1.1); }
}

/* Card Sections */
.card-section {
  display: none;
  flex-direction: column;
  gap: 24px;
  animation: fade-in 0.4s ease;
  margin-top: 15px;
}

.card-section.active {
  display: flex;
}

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

/* Buttons */
.action-btn {
  font-family: var(--font-family);
  background: var(--primary-glow);
  color: #fff;
  border: none;
  padding: 14px 28px;
  border-radius: var(--border-radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: var(--transition-smooth);
  box-shadow: 0 4px 15px var(--color-purple-glow);
}

.action-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--color-purple-glow), 0 0 10px var(--color-cyan-glow);
}

.action-btn:active {
  transform: translateY(0);
}

.action-btn.btn-danger {
  background: var(--color-error);
  box-shadow: 0 4px 15px var(--color-error-glow);
}

.action-btn.btn-danger:hover {
  box-shadow: 0 8px 25px var(--color-error-glow);
}

.text-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-family: var(--font-family);
  font-size: 0.9rem;
  cursor: pointer;
  transition: var(--transition-smooth);
  align-self: center;
  text-decoration: underline;
  text-underline-offset: 4px;
}

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

/* Page 1: Welcome & Setup styling */
.welcome-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 20px;
  margin-top: 15px;
}

@media (max-width: 480px) {
  .welcome-grid {
    grid-template-columns: 1fr;
  }
}

.choice-btn {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-md);
  padding: 32px 20px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 16px;
  color: var(--text-primary);
  font-family: var(--font-family);
  transition: var(--transition-smooth);
  position: relative;
}

.choice-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--border-radius-md);
  padding: 1.5px;
  background: linear-gradient(135deg, transparent 50%, rgba(255, 255, 255, 0.1));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.choice-btn:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-4px);
}

.btn-icon-wrapper {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-smooth);
}

.btn-icon {
  width: 28px;
  height: 28px;
  color: #fff;
}

.send-glow {
  background: linear-gradient(135deg, var(--color-purple), hsl(263, 85%, 45%));
  box-shadow: 0 8px 20px var(--color-purple-glow);
}

.receive-glow {
  background: linear-gradient(135deg, var(--color-cyan), hsl(190, 95%, 35%));
  box-shadow: 0 8px 20px var(--color-cyan-glow);
}

.request-glow {
  background: linear-gradient(135deg, var(--color-success), hsl(145, 75%, 35%));
  box-shadow: 0 8px 20px var(--color-success-glow);
}

.choice-btn h3 {
  font-size: 1.25rem;
  font-weight: 700;
}

.choice-btn p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Join Code Input Section */
.quick-join-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 10px;
  animation: slide-up 0.4s ease;
}

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

.input-group {
  display: flex;
  gap: 12px;
}

.input-group input {
  flex: 1;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-md);
  padding: 14px 18px;
  color: #fff;
  font-family: var(--font-family);
  font-size: 1.1rem;
  text-align: center;
  letter-spacing: 2px;
  outline: none;
  transition: var(--transition-smooth);
}

.input-group input:focus {
  border-color: var(--color-cyan);
  box-shadow: 0 0 12px rgba(0, 206, 209, 0.25);
}

/* Page 2: File Select & Drag-drop Zone */
.drag-drop-zone {
  border: 2px dashed rgba(255, 255, 255, 0.15);
  border-radius: var(--border-radius-lg);
  padding: 40px 20px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  cursor: pointer;
  background: rgba(255, 255, 255, 0.01);
  transition: var(--transition-smooth);
  position: relative;
}

.drag-drop-zone:hover, .drag-drop-zone.dragover {
  border-color: var(--color-purple);
  background: rgba(138, 43, 226, 0.03);
  box-shadow: inset 0 0 15px rgba(138, 43, 226, 0.05);
}

.file-input-hidden {
  display: none;
}

.upload-icon {
  width: 48px;
  height: 48px;
  color: var(--text-secondary);
  transition: var(--transition-smooth);
}

.drag-drop-zone:hover .upload-icon {
  transform: translateY(-4px);
  color: var(--color-purple);
}

.drag-drop-zone h3 {
  font-size: 1.15rem;
  font-weight: 600;
}

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

/* Selected File Card in Drag Zone */
.selected-file-info {
  margin-top: 15px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-md);
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  max-width: 400px;
  animation: scale-up 0.3s ease;
  position: relative;
  z-index: 10;
}

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

.file-icon {
  width: 32px;
  height: 32px;
  color: var(--color-purple);
  flex-shrink: 0;
}

.file-meta {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  overflow: hidden;
  text-align: start;
}

.file-name {
  font-size: 0.95rem;
  font-weight: 500;
  width: 100%;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  direction: ltr; /* English filenames friendly */
}

.file-size {
  font-size: 0.8rem;
  color: var(--text-secondary);
  direction: ltr;
}

.btn-remove-file {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition-smooth);
  padding: 4px;
}

.btn-remove-file:hover {
  color: var(--color-error);
  transform: scale(1.1);
}

/* Share info (Link & Code) */
.share-info-card {
  display: flex;
  flex-direction: column;
  gap: 20px;
  background: rgba(255, 255, 255, 0.02);
  border-radius: var(--border-radius-md);
  padding: 24px;
  border: 1px solid var(--card-border);
}

.share-box {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.share-box label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.share-code-display {
  font-family: 'Outfit', sans-serif;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  color: var(--color-cyan);
  text-shadow: 0 0 8px var(--color-cyan-glow);
  text-align: center;
  background: rgba(0, 0, 0, 0.2);
  border-radius: var(--border-radius-md);
  padding: 14px 12px;
  border: 1px dashed rgba(255, 255, 255, 0.1);
  direction: ltr;
  word-break: break-all;
}

.copy-input-group {
  display: flex;
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-md);
  overflow: hidden;
  direction: ltr;
}

.copy-input-group input {
  flex: 1;
  background: none;
  border: none;
  padding: 12px 16px;
  color: var(--text-secondary);
  font-family: 'Outfit', sans-serif;
  font-size: 0.9rem;
  outline: none;
}

.btn-copy {
  background: rgba(255, 255, 255, 0.05);
  border: none;
  color: var(--text-primary);
  width: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.btn-copy:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--color-cyan);
}

.status-tip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.spin {
  animation: spinner 1.2s infinite linear;
}

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

/* Page 3: Waiting State styling */
.waiting-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 40px 20px;
  text-align: center;
}

.waiting-icon {
  width: 56px;
  height: 56px;
  color: var(--color-cyan);
}

.waiting-state h3 {
  font-size: 1.3rem;
  font-weight: 600;
}

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

/* Page 4: Transfer Progress Styling */
.transfer-header {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.transfer-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.transfer-info h3 {
  font-size: 1.2rem;
  font-weight: 700;
}

.transfer-direction-badge {
  background: var(--primary-glow);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 50px;
}

.file-card-mini {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-md);
  padding: 12px 16px;
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Progress bar container */
.progress-container {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.progress-bar-wrapper {
  height: 10px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 10px;
  overflow: hidden;
  position: relative;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: var(--primary-glow);
  border-radius: 10px;
  transition: width 0.1s linear;
  box-shadow: 0 0 10px var(--color-purple-glow);
}

.progress-stats {
  display: flex;
  justify-content: space-between;
  font-family: 'Outfit', sans-serif;
  font-size: 0.85rem;
  font-weight: 600;
}

.progress-pct {
  color: var(--color-cyan);
}

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

.transfer-details {
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: rgba(0, 0, 0, 0.15);
  border-radius: var(--border-radius-md);
  padding: 16px;
  font-size: 0.9rem;
}

.detail-row {
  display: flex;
  justify-content: space-between;
  color: var(--text-secondary);
}

.detail-row span:last-child {
  color: var(--text-primary);
  font-family: 'Outfit', sans-serif;
  font-weight: 500;
}

/* Page 5: Completion State Styling */
.success-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  text-align: center;
  padding: 20px 0;
}

.success-icon-wrapper {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: rgba(46, 204, 113, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(46, 204, 113, 0.2);
}

.success-icon {
  width: 40px;
  height: 40px;
  color: var(--color-success);
}

.success-state h3 {
  font-size: 1.4rem;
  font-weight: 700;
}

.success-state p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  max-width: 380px;
}

#complete-file-card {
  width: 100%;
  max-width: 360px;
  margin: 10px 0;
}

/* Footer Styling */
.app-footer {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8rem;
  max-width: 480px;
  margin: 0 auto;
}

.app-footer p {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  line-height: 1.5;
}

.app-footer i {
  width: 14px;
  height: 14px;
}

.hidden {
  display: none !important;
}

/* Language Selector */
.lang-selector-container {
  position: absolute;
  top: 20px;
  right: 20px;
  z-index: 100;
}

.lang-select {
  background: rgba(20, 20, 35, 0.6);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-sm);
  color: var(--text-primary);
  padding: 6px 12px;
  font-family: var(--font-family);
  font-size: 0.8rem;
  outline: none;
  cursor: pointer;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: var(--transition-smooth);
}

.lang-select:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--color-cyan);
}

.lang-select option {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
}

/* Modal Overlay & Card styling (Glassmorphism & animations) */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(5, 5, 15, 0.75);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  transition: opacity 0.3s ease;
}

.modal-card {
  background: rgba(20, 20, 35, 0.85);
  border: 1px solid var(--card-border-focus);
  border-radius: var(--border-radius-lg);
  padding: 30px;
  max-width: 420px;
  width: 90%;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5), 0 0 25px var(--color-purple-glow);
  text-align: center;
  animation: modal-enter 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes modal-enter {
  from {
    transform: scale(0.9) translateY(20px);
    opacity: 0;
  }
  to {
    transform: scale(1) translateY(0);
    opacity: 1;
  }
}

.modal-header {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.modal-icon {
  width: 48px;
  height: 48px;
  color: var(--color-cyan);
  filter: drop-shadow(0 0 8px var(--color-cyan-glow));
}

.modal-header h3 {
  font-size: 1.4rem;
  font-weight: 700;
  background: var(--primary-glow);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.modal-body p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 28px;
}

.modal-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.modal-actions .action-btn {
  flex: 1;
  padding: 12px 24px;
}

/* SHA-256 integrity check badges */
.hash-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-sm);
  font-size: 0.75rem;
  font-family: monospace;
  color: var(--text-secondary);
  margin-top: 8px;
}

.hash-badge.success {
  border-color: var(--color-success);
  color: var(--color-success);
  background: var(--color-success-glow);
}

.hash-badge.failed {
  border-color: var(--color-error);
  color: var(--color-error);
  background: var(--color-error-glow);
}