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

:root {
  --bg: #0d0d0d;
  --surface: #1a1a1a;
  --surface2: #242424;
  --like: #4cde8a;
  --nope: #ff5c72;
  --accent: #c084fc;
  --accent2: #818cf8;
  --text: #f5f5f5;
  --text-muted: #888;
  --text-dim: #555;
  --radius: 20px;
  --card-radius: 24px;
  --shadow: 0 20px 60px rgba(0,0,0,0.6);
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ============ PAGES ============ */
.page {
  position: fixed;
  inset: 0;
  display: none;
  flex-direction: column;
  overflow: hidden;
}
.page.active { display: flex; }

/* ============ LOGIN ============ */
#page-login {
  align-items: center;
  justify-content: center;
  background: var(--bg);
}

.login-bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 30% 50%, rgba(192,132,252,0.12) 0%, transparent 60%),
              radial-gradient(ellipse at 70% 20%, rgba(129,140,248,0.1) 0%, transparent 50%),
              radial-gradient(ellipse at 60% 80%, rgba(76,222,138,0.06) 0%, transparent 40%);
}

.art-mosaic {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(2, 1fr);
  gap: 8px;
  padding: 8px;
  opacity: 0.07;
  pointer-events: none;
}
.mosaic-cell {
  border-radius: 12px;
  background: var(--surface2);
}
.m1 { background: linear-gradient(135deg, #8b5cf6, #4338ca); }
.m2 { background: linear-gradient(135deg, #ec4899, #be185d); }
.m3 { background: linear-gradient(135deg, #f59e0b, #b45309); }
.m4 { background: linear-gradient(135deg, #10b981, #047857); }
.m5 { background: linear-gradient(135deg, #3b82f6, #1d4ed8); }
.m6 { background: linear-gradient(135deg, #f43f5e, #be123c); }

.login-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 40px 24px;
  max-width: 420px;
  width: 100%;
}

.logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 12px;
}
.logo-icon {
  font-size: 36px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.logo h1 {
  font-size: 42px;
  font-weight: 800;
  letter-spacing: -1px;
  background: linear-gradient(135deg, var(--text) 40%, var(--text-muted));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.tagline {
  color: var(--text-muted);
  font-size: 16px;
  margin-bottom: 40px;
  line-height: 1.5;
}

.login-form {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 16px;
}

input[type="text"] {
  width: 100%;
  padding: 16px 20px;
  background: var(--surface);
  border: 1px solid var(--surface2);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 16px;
  outline: none;
  transition: border-color 0.2s;
}
input[type="text"]:focus {
  border-color: var(--accent);
}
input[type="text"]::placeholder { color: var(--text-dim); }

.btn-primary {
  width: 100%;
  padding: 16px 24px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.1s;
  letter-spacing: 0.3px;
}
.btn-primary:hover:not(:disabled) { opacity: 0.9; }
.btn-primary:active:not(:disabled) { transform: scale(0.98); }
.btn-primary:disabled { opacity: 0.35; cursor: not-allowed; }

.btn-secondary {
  display: inline-block;
  padding: 14px 20px;
  background: var(--surface2);
  color: var(--text);
  border: none;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s;
  text-align: center;
}
.btn-secondary:hover { background: #2e2e2e; }

.login-note {
  color: var(--text-dim);
  font-size: 13px;
}

.logo-sm {
  font-size: 16px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ============ PREFERENCES ============ */
#page-preferences {
  background: var(--bg);
  overflow: hidden;
}

.pref-header {
  padding: 24px 24px 8px;
  text-align: center;
  flex-shrink: 0;
}
.pref-header p {
  color: var(--text-muted);
  font-size: 15px;
  margin-top: 6px;
}

.pref-sections {
  flex: 1;
  overflow-y: auto;
  padding: 8px 24px;
  -webkit-overflow-scrolling: touch;
}
.pref-sections::-webkit-scrollbar { display: none; }

.pref-section {
  margin-bottom: 28px;
}
.pref-section h2 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
}
.pref-hint {
  color: var(--text-muted);
  font-size: 13px;
  margin-bottom: 12px;
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  padding: 10px 16px;
  background: var(--surface);
  border: 1.5px solid var(--surface2);
  border-radius: 100px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.15s;
  user-select: none;
  color: var(--text-muted);
}
.chip:hover { border-color: var(--accent); color: var(--text); }
.chip.selected {
  background: linear-gradient(135deg, rgba(192,132,252,0.2), rgba(129,140,248,0.2));
  border-color: var(--accent);
  color: var(--text);
  font-weight: 600;
}
.chip .chip-icon { margin-right: 5px; }

.pref-footer {
  padding: 16px 24px 32px;
  border-top: 1px solid var(--surface2);
  flex-shrink: 0;
  background: var(--bg);
}
.pref-count {
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 12px;
}

/* ============ SWIPE PAGE ============ */
#page-swipe {
  background: var(--bg);
}

.swipe-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  flex-shrink: 0;
}

.header-btn {
  background: var(--surface);
  border: 1px solid var(--surface2);
  color: var(--text);
  padding: 8px 16px;
  border-radius: 100px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.header-btn:hover { background: var(--surface2); }

.liked-btn {
  color: var(--like);
  border-color: rgba(76,222,138,0.3);
}

/* ============ CARD STACK ============ */
.card-stack {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 16px;
  overflow: hidden;
}

.card {
  position: absolute;
  width: min(360px, calc(100vw - 32px));
  height: min(520px, calc(100vh - 220px));
  border-radius: var(--card-radius);
  overflow: hidden;
  cursor: grab;
  user-select: none;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
  will-change: transform;
}
.card:active { cursor: grabbing; }

.card-stack .card:nth-child(1) { z-index: 10; }
.card-stack .card:nth-child(2) { z-index: 5; transform: scale(0.95) translateY(18px); }
.card-stack .card:nth-child(3) { z-index: 1; transform: scale(0.90) translateY(34px); }
.card-stack .card:nth-child(n+4) { z-index: 0; transform: scale(0.85) translateY(46px); opacity: 0; }

.card-top {
  z-index: 10;
}

.card-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  pointer-events: none;
  background: var(--surface);
}

.card-info {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 60px 20px 20px;
  background: linear-gradient(to top, rgba(0,0,0,0.85) 0%, transparent 100%);
}
.card-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
  line-height: 1.2;
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
}
.card-artist {
  font-size: 13px;
  color: rgba(255,255,255,0.75);
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
}
.card-dept {
  font-size: 11px;
  color: rgba(255,255,255,0.5);
  margin-top: 2px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Swipe indicators */
.card-indicator {
  position: absolute;
  top: 28px;
  padding: 8px 18px;
  border-radius: 8px;
  font-size: 22px;
  font-weight: 900;
  letter-spacing: 1px;
  opacity: 0;
  transition: opacity 0.05s;
  pointer-events: none;
  border: 3px solid;
  z-index: 20;
}
.card-indicator.love {
  left: 20px;
  color: var(--like);
  border-color: var(--like);
  transform: rotate(-15deg);
}
.card-indicator.nope {
  right: 20px;
  color: var(--nope);
  border-color: var(--nope);
  transform: rotate(15deg);
}

/* Loading / Empty states */
.loading-state, .empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  text-align: center;
  color: var(--text-muted);
  padding: 40px;
}
.empty-state .empty-icon {
  font-size: 48px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.empty-state h3 { font-size: 22px; color: var(--text); }
.empty-state p { font-size: 15px; }
.empty-state .btn-primary { width: auto; margin-top: 8px; }

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--surface2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ============ SWIPE ACTIONS ============ */
.swipe-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 16px 24px 8px;
  flex-shrink: 0;
}

.action-btn {
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.15s, box-shadow 0.15s;
  font-size: 22px;
  line-height: 1;
}
.action-btn:hover { transform: scale(1.1); }
.action-btn:active { transform: scale(0.95); }

.action-skip {
  width: 60px;
  height: 60px;
  background: rgba(255,92,114,0.15);
  color: var(--nope);
  border: 2px solid rgba(255,92,114,0.3);
}
.action-skip:hover { background: rgba(255,92,114,0.25); box-shadow: 0 0 20px rgba(255,92,114,0.3); }

.action-info {
  width: 48px;
  height: 48px;
  background: var(--surface);
  color: var(--text-muted);
  border: 2px solid var(--surface2);
  font-size: 16px;
  font-style: italic;
  font-weight: 700;
}

.action-like {
  width: 60px;
  height: 60px;
  background: rgba(76,222,138,0.15);
  color: var(--like);
  border: 2px solid rgba(76,222,138,0.3);
}
.action-like:hover { background: rgba(76,222,138,0.25); box-shadow: 0 0 20px rgba(76,222,138,0.3); }

.keyboard-hint {
  text-align: center;
  font-size: 11px;
  color: var(--text-dim);
  padding: 4px 0 16px;
  flex-shrink: 0;
}

/* ============ PROFILE PAGE ============ */
#page-profile {
  background: var(--bg);
  overflow: hidden;
}

.profile-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--surface2);
  flex-shrink: 0;
}
.profile-title { text-align: center; }
.profile-title h2 { font-size: 16px; font-weight: 700; }
.profile-title p { font-size: 12px; color: var(--text-muted); margin-top: 2px; }

.liked-grid {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  -webkit-overflow-scrolling: touch;
  columns: 2;
  column-gap: 12px;
}
.liked-grid::-webkit-scrollbar { display: none; }

@media (min-width: 600px) { .liked-grid { columns: 3; } }
@media (min-width: 900px) { .liked-grid { columns: 4; } }

.liked-item {
  break-inside: avoid;
  margin-bottom: 12px;
  border-radius: 16px;
  overflow: hidden;
  background: var(--surface);
  position: relative;
  cursor: pointer;
  transition: transform 0.15s;
}
.liked-item:hover { transform: scale(1.02); }
.liked-item img {
  width: 100%;
  display: block;
  aspect-ratio: auto;
  max-height: 300px;
  object-fit: cover;
}
.liked-item-info {
  padding: 8px 10px;
}
.liked-item-title {
  font-size: 12px;
  font-weight: 600;
  line-height: 1.3;
  margin-bottom: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.liked-item-artist {
  font-size: 11px;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.liked-item-download {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 30px;
  height: 30px;
  background: rgba(0,0,0,0.6);
  border: none;
  border-radius: 50%;
  color: #fff;
  font-size: 14px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.15s;
  backdrop-filter: blur(4px);
}
.liked-item:hover .liked-item-download { opacity: 1; }

.empty-collection {
  column-span: all;
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
  line-height: 2;
}

/* ============ MODAL ============ */
.modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: flex-end;
}

@media (min-width: 600px) {
  .modal { align-items: center; justify-content: center; }
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(4px);
}

.modal-content {
  position: relative;
  z-index: 1;
  background: var(--surface);
  border-radius: 24px 24px 0 0;
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  padding-bottom: env(safe-area-inset-bottom);
}
@media (min-width: 600px) {
  .modal-content {
    border-radius: 24px;
    max-height: 80vh;
  }
}
.modal-content::-webkit-scrollbar { display: none; }

.modal-close {
  position: sticky;
  top: 0;
  float: right;
  margin: 16px 16px 0 0;
  background: var(--surface2);
  border: none;
  color: var(--text);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  font-size: 14px;
  cursor: pointer;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content img {
  width: 100%;
  max-height: 320px;
  object-fit: contain;
  display: block;
  background: #111;
}

.modal-info {
  padding: 20px;
}
.modal-info h2 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.3;
}
.modal-info p {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 6px;
  line-height: 1.5;
}
.modal-info p:empty { display: none; }

.modal-actions {
  display: flex;
  gap: 12px;
  margin-top: 20px;
}
.modal-actions .btn-primary {
  flex: 1;
  width: auto;
}
.modal-actions .btn-secondary {
  flex: 1;
}

/* ============ ANIMATIONS ============ */
@keyframes slideInRight {
  from { transform: translateX(60px); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}
@keyframes slideInUp {
  from { transform: translateY(30px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

.card-enter {
  animation: slideInUp 0.3s ease;
}

/* Fly-off animations */
.card-fly-right {
  transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94), opacity 0.4s !important;
  transform: translateX(120vw) rotate(30deg) !important;
  opacity: 0;
}
.card-fly-left {
  transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94), opacity 0.4s !important;
  transform: translateX(-120vw) rotate(-30deg) !important;
  opacity: 0;
}

/* Like pulse on header button */
@keyframes heartPulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.3); }
  100% { transform: scale(1); }
}
.heart-pulse { animation: heartPulse 0.3s ease; }