/* ============================================================
   style.css — Google Material Design 3 inspired styles
   ============================================================ */

/* ---------- Google Font ---------- */
@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&family=Google+Sans:wght@400;500;700&display=swap');

/* ---------- CSS Custom Properties (Material Design tokens) ---------- */
:root {
  --md-primary:         #1a73e8;
  --md-primary-dark:    #1557b0;
  --md-primary-light:   #e8f0fe;
  --md-on-primary:      #ffffff;
  --md-surface:         #ffffff;
  --md-on-surface:      #202124;
  --md-on-surface-dim:  #5f6368;
  --md-outline:         #dadce0;
  --md-error:           #d93025;
  --md-error-light:     #fce8e6;
  --md-success:         #188038;
  --md-success-light:   #e6f4ea;
  --md-background:      #f8f9fa;

  --md-shadow-1: 0 1px 2px rgba(60,64,67,.3), 0 1px 3px 1px rgba(60,64,67,.15);
  --md-shadow-2: 0 1px 2px rgba(60,64,67,.3), 0 2px 6px 2px rgba(60,64,67,.15);
  --md-shadow-3: 0 4px 8px 3px rgba(60,64,67,.15), 0 1px 3px rgba(60,64,67,.3);

  --md-radius-sm:  4px;
  --md-radius-md:  8px;
  --md-radius-lg:  16px;
  --md-radius-xl:  28px;

  --md-transition: 200ms cubic-bezier(0.2, 0, 0, 1);
}

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

html, body {
  height: 100%;
}

body {
  font-family: 'Roboto', 'Google Sans', Arial, sans-serif;
  background: var(--md-background);
  color: var(--md-on-surface);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ---------- Screen management ---------- */
.screen {
  display: none;
  min-height: 100vh;
}
.screen.active {
  display: flex;
}

/* ---------- Utility ---------- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  clip: rect(0,0,0,0);
  overflow: hidden;
}

/* ============================================================
   SCREEN 1 — Sign In
   ============================================================ */
#screen-signin {
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.signin-card {
  background: var(--md-surface);
  border-radius: var(--md-radius-lg);
  box-shadow: var(--md-shadow-2);
  padding: 40px 36px 36px;
  max-width: 480px;
  width: 100%;
  text-align: center;
}

/* YouTube logo mark */
.youtube-logo-mark {
  width: 64px;
  height: 44px;
  margin: 0 auto 24px;
  display: block;
}

.signin-card h1 {
  font-family: 'Google Sans', 'Roboto', sans-serif;
  font-size: 24px;
  font-weight: 500;
  color: var(--md-on-surface);
  margin-bottom: 8px;
  letter-spacing: 0;
}

.signin-card .subtitle {
  font-size: 14px;
  color: var(--md-on-surface-dim);
  margin-bottom: 24px;
  line-height: 1.5;
}

/* App info & purpose box (Google OAuth verification) */
.app-info-box {
  background: var(--md-background);
  border: 1px solid var(--md-outline);
  border-radius: var(--md-radius-md);
  padding: 18px 20px;
  margin-bottom: 24px;
  text-align: left;
}

.app-info-box h2 {
  font-size: 15px;
  font-weight: 500;
  color: var(--md-on-surface);
  margin-bottom: 6px;
}

.app-info-box h3 {
  font-size: 13px;
  font-weight: 500;
  color: var(--md-on-surface);
  margin-top: 12px;
  margin-bottom: 4px;
}

.app-info-box p {
  font-size: 12.5px;
  color: var(--md-on-surface-dim);
  line-height: 1.5;
}

/* Privacy notice box */
.privacy-notice {
  background: var(--md-primary-light);
  border-radius: var(--md-radius-md);
  padding: 16px;
  margin-bottom: 32px;
  text-align: left;
}

.privacy-notice h2 {
  font-size: 13px;
  font-weight: 500;
  color: var(--md-primary-dark);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.privacy-notice ul {
  list-style: none;
  padding: 0;
}

.privacy-notice ul li {
  font-size: 13px;
  color: #174ea6;
  padding: 3px 0;
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.4;
}

.privacy-notice ul li::before {
  content: '•';
  flex-shrink: 0;
  margin-top: 1px;
}

/* Official Google Sign-In button */
.google-signin-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: var(--md-surface);
  color: #3c4043;
  border: 1px solid var(--md-outline);
  border-radius: var(--md-radius-sm);
  padding: 0 16px;
  height: 40px;
  font-family: 'Roboto', sans-serif;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--md-transition), box-shadow var(--md-transition);
  width: 100%;
  justify-content: center;
  letter-spacing: 0.25px;
  text-decoration: none;
}

.google-signin-btn:hover {
  background: #f8f9fa;
  box-shadow: var(--md-shadow-1);
}

.google-signin-btn:active {
  background: #e8eaed;
}

.google-signin-btn svg {
  flex-shrink: 0;
}

.google-signin-btn .btn-text {
  flex: 1;
  text-align: center;
}

/* Error message */
.signin-error {
  display: none;
  margin-top: 16px;
  padding: 12px 16px;
  background: var(--md-error-light);
  border-radius: var(--md-radius-sm);
  color: var(--md-error);
  font-size: 13px;
  text-align: left;
  line-height: 1.5;
}
.signin-error.visible { display: block; }

/* Legal links (Privacy Policy · Terms of Service) */
.legal-links {
  margin-top: 20px;
  font-size: 12px;
  color: var(--md-on-surface-dim);
  text-align: center;
}

.legal-links a {
  color: var(--md-on-surface-dim);
  text-decoration: none;
  transition: color 150ms;
}

.legal-links a:hover {
  color: var(--md-primary);
  text-decoration: underline;
}

/* ============================================================
   SCREEN 2 — Importing (progress)
   ============================================================ */
#screen-importing {
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 32px;
  padding: 24px;
}

/* Material circular progress */
.md-progress-ring {
  width: 64px;
  height: 64px;
  animation: md-rotate 1.4s linear infinite;
}

.md-progress-ring circle {
  fill: none;
  stroke: var(--md-primary);
  stroke-width: 4;
  stroke-dasharray: 150 50;
  stroke-linecap: round;
  animation: md-dash 1.4s ease-in-out infinite;
  transform-origin: center;
}

@keyframes md-rotate {
  100% { transform: rotate(360deg); }
}

@keyframes md-dash {
  0%   { stroke-dasharray: 1 200; stroke-dashoffset: 0; }
  50%  { stroke-dasharray: 90 200; stroke-dashoffset: -35px; }
  100% { stroke-dasharray: 90 200; stroke-dashoffset: -124px; }
}

.importing-title {
  font-family: 'Google Sans', sans-serif;
  font-size: 18px;
  font-weight: 500;
  color: var(--md-on-surface);
}

.importing-subtitle {
  font-size: 14px;
  color: var(--md-on-surface-dim);
  margin-top: -24px;
}

/* ============================================================
   SCREEN 3 — Result (success / failure)
   ============================================================ */
#screen-result {
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.result-card {
  background: var(--md-surface);
  border-radius: var(--md-radius-lg);
  box-shadow: var(--md-shadow-2);
  padding: 48px 40px;
  max-width: 420px;
  width: 100%;
  text-align: center;
}

.result-icon {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  font-size: 36px;
}

.result-icon.success {
  background: var(--md-success-light);
  color: var(--md-success);
}

.result-icon.error {
  background: var(--md-error-light);
  color: var(--md-error);
}

.result-title {
  font-family: 'Google Sans', sans-serif;
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 8px;
}

.result-subtitle {
  font-size: 14px;
  color: var(--md-on-surface-dim);
  line-height: 1.6;
  margin-bottom: 28px;
}

.countdown-badge {
  display: inline-block;
  background: var(--md-primary-light);
  color: var(--md-primary-dark);
  border-radius: var(--md-radius-xl);
  padding: 8px 20px;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 16px;
}

/* Retry / action buttons */
.md-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  border-radius: var(--md-radius-xl);
  padding: 10px 24px;
  font-family: 'Roboto', sans-serif;
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.25px;
  cursor: pointer;
  transition: background var(--md-transition), box-shadow var(--md-transition);
  text-decoration: none;
}

.md-btn-filled {
  background: var(--md-primary);
  color: var(--md-on-primary);
}
.md-btn-filled:hover {
  background: var(--md-primary-dark);
  box-shadow: var(--md-shadow-1);
}

.md-btn-outlined {
  background: transparent;
  color: var(--md-primary);
  border: 1px solid var(--md-outline);
}
.md-btn-outlined:hover {
  background: var(--md-primary-light);
}

.result-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: center;
}

/* ============================================================
   SCREEN 4 — Admin Panel
   ============================================================ */
#screen-admin {
  flex-direction: column;
}

/* Top App Bar */
.app-bar {
  background: var(--md-surface);
  border-bottom: 1px solid var(--md-outline);
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--md-shadow-1);
}

.app-bar-title {
  font-family: 'Google Sans', sans-serif;
  font-size: 20px;
  font-weight: 500;
  color: var(--md-on-surface);
  display: flex;
  align-items: center;
  gap: 12px;
}

.app-bar-title .admin-chip {
  font-size: 11px;
  font-weight: 500;
  background: var(--md-primary-light);
  color: var(--md-primary);
  border-radius: var(--md-radius-xl);
  padding: 2px 10px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.signout-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  background: transparent;
  color: var(--md-on-surface-dim);
  border: 1px solid var(--md-outline);
  border-radius: var(--md-radius-xl);
  padding: 6px 16px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--md-transition);
}
.signout-btn:hover {
  background: #f1f3f4;
}

/* Admin body */
.admin-body {
  flex: 1;
  padding: 32px 24px;
  max-width: 960px;
  margin: 0 auto;
  width: 100%;
}

.admin-header {
  margin-bottom: 28px;
}

.admin-header h2 {
  font-family: 'Google Sans', sans-serif;
  font-size: 22px;
  font-weight: 500;
  color: var(--md-on-surface);
}

.admin-header p {
  font-size: 14px;
  color: var(--md-on-surface-dim);
  margin-top: 4px;
}

/* Stats row */
.admin-stats {
  display: flex;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

.stat-chip {
  background: var(--md-surface);
  border: 1px solid var(--md-outline);
  border-radius: var(--md-radius-md);
  padding: 12px 20px;
  font-size: 13px;
  color: var(--md-on-surface-dim);
  box-shadow: var(--md-shadow-1);
  display: flex;
  align-items: center;
  gap: 8px;
}

.stat-chip strong {
  color: var(--md-on-surface);
  font-size: 20px;
  font-weight: 500;
}

/* Download All */
.admin-actions {
  margin-bottom: 24px;
}

/* User cards list */
.users-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.user-card {
  background: var(--md-surface);
  border-radius: var(--md-radius-md);
  border: 1px solid var(--md-outline);
  box-shadow: var(--md-shadow-1);
  overflow: hidden;
  transition: box-shadow var(--md-transition);
}
.user-card:hover {
  box-shadow: var(--md-shadow-2);
}

.user-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  cursor: pointer;
  user-select: none;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--md-primary-light);
  color: var(--md-primary);
  font-size: 18px;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
}

.user-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
}

.user-info {
  flex: 1;
}

.user-name {
  font-size: 15px;
  font-weight: 500;
  color: var(--md-on-surface);
}

.user-email {
  font-size: 13px;
  color: var(--md-on-surface-dim);
  margin-top: 2px;
}

.user-meta {
  display: flex;
  gap: 16px;
  margin-left: auto;
  align-items: center;
  flex-shrink: 0;
}

.meta-badge {
  font-size: 12px;
  color: var(--md-on-surface-dim);
  text-align: right;
}

.meta-badge strong {
  display: block;
  font-size: 16px;
  font-weight: 500;
  color: var(--md-on-surface);
}

.expand-icon {
  color: var(--md-on-surface-dim);
  transition: transform var(--md-transition);
  flex-shrink: 0;
}
.user-card.expanded .expand-icon {
  transform: rotate(180deg);
}

/* Expandable JSON panel */
.user-card-body {
  display: none;
  border-top: 1px solid var(--md-outline);
}
.user-card.expanded .user-card-body {
  display: block;
}

.json-toolbar {
  display: flex;
  justify-content: flex-end;
  padding: 12px 24px 0;
}

.json-viewer {
  background: #1e1e2e;
  color: #cdd6f4;
  font-family: 'Roboto Mono', 'Courier New', monospace;
  font-size: 12.5px;
  line-height: 1.6;
  padding: 20px 24px;
  overflow-x: auto;
  max-height: 320px;
  overflow-y: auto;
  white-space: pre;
  margin: 12px 24px 0;
  border-radius: var(--md-radius-md);
}

/* JSON syntax coloring */
.json-viewer .json-key    { color: #89b4fa; }
.json-viewer .json-str    { color: #a6e3a1; }
.json-viewer .json-num    { color: #fab387; }
.json-viewer .json-bool   { color: #f38ba8; }
.json-viewer .json-null   { color: #6c7086; }

.user-card-footer {
  display: flex;
  justify-content: flex-end;
  padding: 16px 24px;
  gap: 12px;
}

/* Empty state */
.empty-state {
  text-align: center;
  padding: 64px 24px;
  color: var(--md-on-surface-dim);
}

.empty-state .empty-icon {
  font-size: 48px;
  margin-bottom: 16px;
}

.empty-state p {
  font-size: 16px;
}

/* Admin loading */
.admin-loading {
  text-align: center;
  padding: 48px;
  color: var(--md-on-surface-dim);
  font-size: 14px;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 600px) {
  .signin-card {
    padding: 36px 24px 32px;
  }

  .admin-body {
    padding: 20px 16px;
  }

  .app-bar {
    padding: 0 16px;
  }

  .user-card-header {
    flex-wrap: wrap;
    padding: 16px;
  }

  .user-meta {
    margin-left: 60px;
    margin-top: -8px;
  }

  .admin-stats {
    flex-direction: column;
  }

  .result-card {
    padding: 36px 24px;
  }
}