/* ----------  DESIGN TOKENS (all in rem)  ---------- */
:root {
  /* ---- core font-size (change only this to scale everything) ---- */
  --base-fs: 1rem; /* 16 px default */

  /* ---- colours ---- */
  --primary: #667eea;
  --primary-dark: #764ba2;
  --accent: #ff6b6b;
  --success: #4d96ff;
  --error: #ff6b6b;
  --text: #333;
  --text-light: #666;
  --bg: #f8f9fa;
  --card: #fff;
  --border: #e1e5e9;
  --mint: #56d08a;
  --bar-primary: #ffa500;
  --unrated-primary: #ffffff;
  --unrated-secondary: #adb5bd;

  /* ---- spacing (1 unit = .25 rem = 4 px) ---- */
  --sp-xs: calc(var(--base-fs) * 0.25); /* 4 */
  --sp-sm: calc(var(--base-fs) * 0.5); /* 8 */
  --sp-md: calc(var(--base-fs) * 1); /* 16 */
  --sp-lg: calc(var(--base-fs) * 1.5); /* 24 */
  --sp-xl: calc(var(--base-fs) * 2); /* 32 */
  --sp-2xl: calc(var(--base-fs) * 2.5); /* 40 */

  /* ---- typography ---- */
  --fs-xs: calc(var(--base-fs) * 0.75); /* 12 */
  --fs-sm: calc(var(--base-fs) * 0.875); /* 14 */
  --fs-base: var(--base-fs); /* 16 */
  --fs-lg: calc(var(--base-fs) * 1.125); /* 18 */
  --fs-xl: calc(var(--base-fs) * 1.375); /* 22 */
  --fs-2xl: calc(var(--base-fs) * 1.625); /* 26 */
  --fs-3xl: calc(var(--base-fs) * 2); /* 32 */
  --fs-4xl: calc(var(--base-fs) * 2.5); /* 40 */
  --fs-5xl: calc(var(--base-fs) * 3.5); /* 56 */
  --fs-6xl: calc(var(--base-fs) * 5); /* 80 */

  /* ---- radius ---- */
  --r-sm: calc(var(--base-fs) * 0.25); /* 4 */
  --r-md: calc(var(--base-fs) * 0.5); /* 8 */
  --r-lg: calc(var(--base-fs) * 1); /* 16 */
  --r-xl: calc(var(--base-fs) * 1.25); /* 20 */
  --r-2xl: calc(var(--base-fs) * 1.5); /* 24 */

  /* ---- shadows / fx ---- */
  --shadow: 0 0.25rem 0.75rem rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 0.5rem 1.5rem rgba(0, 0, 0, 0.15);
  --transition: all 0.3s ease;
  --blur: blur(0.625rem);
}

/* ----------  RESET & BASE STYLES  ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  font-size: 16px;
}
body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  padding: var(--sp-lg);
}
img,
picture {
  max-width: 100%;
  display: block;
}
button,
input {
  font: inherit;
}

/* ----------  LOGIN VIEW / MAIN CONTAINER  ---------- */
.container {
  max-width: 50rem;
  margin: 0 auto;
  background: var(--card);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
header {
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: #fff;
  padding: var(--sp-2xl) var(--sp-lg);
  text-align: center;
}
header h1 {
  font-size: var(--fs-4xl);
  font-weight: 800;
  margin-bottom: var(--sp-sm);
}
.subtitle {
  font-size: var(--fs-lg);
  opacity: 0.9;
  max-width: 30rem;
  margin: 0 auto;
}

/* Form Elements */
.form-section,
.results-section,
.error-section,
.info-section {
  padding: var(--sp-xl);
}
.form-group {
  margin-bottom: var(--sp-md);
}
label {
  display: block;
  margin-bottom: var(--sp-xs);
  font-weight: 600;
}
input {
  width: 100%;
  padding: var(--sp-sm);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  transition: var(--transition);
}
input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 0.125rem rgba(102, 126, 234, 0.1);
}
input::placeholder {
  color: #999;
  opacity: 1;
}
small {
  display: block;
  margin-top: var(--sp-xs);
  color: var(--text-light);
  font-size: var(--fs-sm);
}

/* Buttons */
.generate-btn {
  width: 100%;
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: #fff;
  border: none;
  padding: var(--sp-md);
  border-radius: var(--r-lg);
  font-size: var(--fs-lg);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}
.generate-btn:hover:not(:disabled) {
  transform: translateY(-0.125rem);
  box-shadow: var(--shadow-lg);
}
.generate-btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
  transform: none;
}
.secondary-btn {
  background: transparent;
  color: var(--primary);
  border: 0.125rem solid var(--primary);
  padding: var(--sp-sm) var(--sp-md);
  border-radius: var(--r-lg);
  font-size: var(--fs-base);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  margin-top: var(--sp-sm);
}
#demoBtn {
  width: 100%;
}
.secondary-btn:hover {
  background: var(--primary);
  color: #fff;
}

/* Progress Bar */
.progress-bar {
  width: 100%;
  height: 0.5rem;
  background: rgba(255, 255, 255, 0.3);
  border-radius: var(--r-sm);
  overflow: hidden;
  margin-bottom: var(--sp-sm);
}
.progress-fill {
  height: 100%;
  background: #fff;
  border-radius: var(--r-sm);
  transition: width 0.3s ease;
  width: 0;
}
.progress-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--sp-xs);
}
.progress-percent {
  font-weight: 600;
  font-size: var(--fs-base);
}
.progress-message {
  font-size: var(--fs-sm);
  opacity: 0.9;
}
.progress-details {
  font-size: var(--fs-xs);
  opacity: 0.7;
  text-align: left;
}

/* Results & Messages */
.success-message,
.error-message {
  text-align: center;
  padding: var(--sp-lg);
  border-radius: var(--r-lg);
}
.success-message {
  background: rgba(77, 150, 255, 0.1);
}
.error-message {
  background: rgba(255, 107, 107, 0.1);
  border-left: 0.25rem solid var(--error);
}
.success-icon,
.error-icon {
  font-size: var(--fs-4xl);
  margin-bottom: var(--sp-sm);
}
.quick-stats {
  background: rgba(102, 126, 234, 0.05);
  padding: var(--sp-md);
  border-radius: var(--r-lg);
  border-left: 0.25rem solid var(--primary);
  margin-bottom: var(--sp-lg);
}

/* Info Section */
.info-section {
  background: #f3f4f6;
  border-left: 0.25rem solid #9ca3af;
  padding: var(--sp-md);
  border-radius: var(--r-lg);
  margin: var(--sp-xl);
  margin-top: var(--sp-md);
  color: var(--text-light);
  line-height: 1.5;
}

/* Quick Stats */
#quickStats {
  text-align: center;
  margin: var(--sp-md) 0;
}

/* ----------  WRAPPED VIEW  ---------- */
.wrapped-view {
  display: none;
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  min-height: 100vh;
  color: #fff;
  overflow-x: hidden;
  position: fixed;
  inset: 0;
  z-index: 10;
  overflow-y: auto;
}
.wrapped-container {
  max-width: 100%;
  margin: 0;
  padding: 0;
  font-family: inherit;
  min-height: 100%;
}
.wrapped-section {
  min-height: 100vh;
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: var(--sp-lg);
  text-align: center;
  opacity: 0;
  transform: translateY(3.125rem);
  transition: all 0.8s ease;
  position: absolute;
  inset: 0;
  box-sizing: border-box;
}
.wrapped-section.active {
  display: flex;
  opacity: 1;
  transform: translateY(0);
  position: relative;
}

/* Wrapped Typography */
.section-title {
  font-size: var(--fs-5xl);
  font-weight: 800;
  margin-bottom: var(--sp-sm);
  text-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.3);
}
.section-subtitle {
  font-size: var(--fs-2xl);
  margin-bottom: var(--sp-lg);
  opacity: 0.9;
}
.diversity-score {
  font-size: var(--fs-6xl);
  font-weight: 800;
  background: linear-gradient(
    45deg,
    #ff6b6b,
    var(--bar-primary),
    #ffd93d,
    #6bcf7f,
    #4d96ff
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin: var(--sp-sm) 0;
}
#last-played {
  font-size: var(--fs-base);
  opacity: 0.8;
  margin-top: -0.7rem;
  margin-bottom: 1rem;
}

/* Stats Grid & Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15.625rem, 1fr));
  gap: var(--sp-lg);
  margin: var(--sp-lg) 0;
  max-width: 75rem;
  width: 100%;
}
#welcomeStats {
  grid-template-columns: repeat(4, 1fr);
}
#diversity-stats,
#summary-stats {
  grid-template-columns: repeat(3, 1fr);
}
.stat-card {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: var(--blur);
  border-radius: var(--r-2xl);
  padding: var(--sp-lg);
  border: 1px solid rgba(255, 255, 255, 0.2);
}
.stat-number {
  font-size: var(--fs-4xl);
  font-weight: 800;
  margin-bottom: var(--sp-xs);
}
.stat-label {
  font-size: var(--fs-lg);
  opacity: 0.9;
}

/* Top Lists */
.top-list {
  list-style: none;
  padding: 0;
  max-width: 37.5rem;
  width: 100%;
}
.top-item {
  background: rgba(255, 255, 255, 0.1);
  margin: var(--sp-sm) 0;
  padding: var(--sp-md);
  padding-right: 1.5rem;
  border-radius: var(--r-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  backdrop-filter: var(--blur);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.rank {
  font-size: var(--fs-3xl);
  font-weight: 800;
  margin-right: var(--sp-sm);
}
.item-info {
  flex: 1;
  text-align: left;
}
.item-name {
  font-size: var(--fs-xl);
  font-weight: 600;
  margin-bottom: -0.2rem;
}
.item-detail {
  opacity: 0.8;
  font-size: var(--fs-base);
}

/* Wrapped Progress Bars */
.wrapped-progress-bar {
  width: 100%;
  height: 0.5rem;
  background: rgba(255, 255, 255, 0.2);
  border-radius: var(--r-sm);
  overflow: hidden;
  margin: var(--sp-sm) 0;
}
.wrapped-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--bar-primary));
  border-radius: var(--r-sm);
  transition: width 1s ease;
}

/* Navigation */
.navigation {
  position: fixed;
  bottom: var(--sp-lg);
  left: 50%;
  transform: translateX(-50%);
  z-index: 1000;
  display: flex;
  gap: var(--sp-sm);
}
.nav-btn {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  color: #fff;
  width: 3.75rem;
  height: 3.75rem;
  border-radius: 50%;
  cursor: pointer;
  backdrop-filter: var(--blur);
  border: 1px solid rgba(255, 255, 255, 0.2);
  transition: all 0.3s ease;
  font-size: var(--fs-2xl);
  display: flex;
  align-items: center;
  justify-content: center;
}
.nav-btn:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.3);
  transform: translateY(-0.125rem) scale(1.05);
}
.nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
  transform: none;
}

/* Highlights & Share */
.summary-highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(12.5rem, 1fr));
  gap: var(--sp-md);
  margin: var(--sp-lg) 0;
  max-width: 50rem;
  width: 100%;
}
.highlight-card {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: var(--blur);
  border-radius: var(--r-xl);
  padding: var(--sp-md);
  border: 1px solid rgba(255, 255, 255, 0.2);
  text-align: center;
}
.highlight-icon {
  font-size: var(--fs-4xl);
  margin-bottom: var(--sp-xs);
}
.highlight-value {
  font-size: var(--fs-3xl);
  font-weight: 700;
  margin-bottom: 0.3rem;
}
.highlight-label {
  font-size: var(--fs-base);
  opacity: 0.9;
}
.share-button {
  background: linear-gradient(90deg, var(--accent), var(--bar-primary));
  border: none;
  color: #fff;
  padding: var(--sp-sm) var(--sp-lg);
  border-radius: 3.125rem;
  font-size: var(--fs-xl);
  font-weight: 600;
  cursor: pointer;
  margin-top: -1.3rem;
  transition: all 0.3s ease;
  backdrop-filter: var(--blur);
  border: 1px solid rgba(255, 255, 255, 0.2);
}
.share-button:hover {
  transform: translateY(-0.125rem) scale(1.05);
  box-shadow: 0 0.625rem 1.25rem rgba(0, 0, 0, 0.2);
}
.share-button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* Generate Again Button */
#generate-again {
  margin-bottom: 5rem;
}

/* ----------  CHARTS  ---------- */
.chart-container {
  position: relative;
  z-index: 10;
  width: 90%;
  max-width: 43.75rem;
  margin: var(--sp-lg) auto;
}
.chart-wrapper {
  border-radius: var(--r-md);
  overflow: visible;
  box-shadow: var(--shadow);
}
.chart-bar {
  display: flex;
  height: 2.25rem;
  overflow: hidden;
  border-radius: var(--r-md);
}
.chart-segment {
  position: relative;
  cursor: pointer;
  transition: transform 0.15s;
  display: block;
  height: 2.25rem;
  flex: 0 0 auto;
}
.chart-segment:hover {
  transform: scaleY(1.08);
  z-index: 2;
  border: 1.5px solid rgba(0, 0, 0, 0.45);
  box-sizing: border-box;
}
.chart-segment:hover::after {
  content: attr(data-label) "  |  " attr(data-songs) " songs  |  "
    attr(data-plays) " plays (" attr(data-pct) ")";
  position: absolute;
  top: -2.375rem;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.9);
  color: #fff;
  padding: 0.375rem 0.625rem;
  border-radius: var(--r-sm);
  font-size: var(--fs-xs);
  white-space: nowrap;
  pointer-events: none;
  z-index: 9999;
}
.chart-key {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.6rem 1.2rem;
  margin-top: 1.2rem;
  font-size: var(--fs-xs);
}
.chart-key-item {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.chart-key-color {
  width: 0.875rem;
  height: 0.875rem;
  border-radius: 0.1875rem;
}

/* ----------  RATING / TOP-LIST COMPONENTS  ---------- */
.rating-horizontal-container {
  display: flex;
  flex-direction: column;
  gap: var(--sp-lg);
  max-width: 75rem;
  width: 100%;
  margin: var(--sp-lg) auto;
}
.rating-cards-horizontal {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-md);
  width: 100%;
}
.rating-cards-horizontal .stat-card {
  min-height: 7.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.horizontal-rating-chart {
  display: flex;
  flex-direction: column;
  gap: var(--sp-sm);
  width: 100%;
}
.horizontal-rating-bar-container {
  display: flex;
  align-items: center;
  gap: var(--sp-md);
  width: 100%;
}
.horizontal-rating-label {
  font-size: var(--fs-sm);
  font-weight: 600;
  min-width: 3.75rem;
  text-align: right;
}
.horizontal-rating-bar-wrapper {
  flex: 1;
  height: 1.875rem;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--r-md);
  overflow: hidden;
  position: relative;
}
.horizontal-rating-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--bar-primary), var(--accent));
  border-radius: var(--r-md);
  transition: width 1s ease;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding: 0 var(--sp-sm);
  min-width: 3%;
}
#unrated {
  background: linear-gradient(
    90deg,
    var(--unrated-primary),
    var(--unrated-secondary)
  );
}
.horizontal-rating-count {
  font-size: var(--fs-sm);
  font-weight: 600;
  color: #fff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}
.horizontal-rating-percentage {
  font-size: var(--fs-sm);
  font-weight: 600;
  min-width: 3.125rem;
  text-align: right;
}

/* Top List Layout */
.top-list-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-lg);
  align-items: stretch;
  max-width: 75rem;
  width: 100%;
  margin: var(--sp-lg) auto;
}
.top-list-left,
.top-list-right {
  display: flex;
  flex-direction: column;
  height: 100%;
}
.top-list-main,
.top-list-compact {
  flex: 1 1 auto;
  display: flex;
  flex-direction: column;
  margin: 0;
  padding: 0;
  gap: var(--sp-sm);
}
.top-list-compact {
  justify-content: space-between;
}

/* Compact Top Items */
.top-item-compact {
  background: rgba(255, 255, 255, 0.1);
  margin: var(--sp-xs) 0;
  padding: var(--sp-sm);
  padding-right: 1.5rem;
  border-radius: var(--r-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  backdrop-filter: var(--blur);
  border: 1px solid rgba(255, 255, 255, 0.2);
  flex: 1;
  min-height: 0;
}
.top-item,
.top-item-compact {
  margin: 0 !important;
}

.top-item .item-name,
.top-item .item-detail,
.top-item-compact .compact-name,
.top-item-compact .compact-detail {
  max-width: 30vw;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.compact-rank {
  font-size: var(--fs-lg);
  font-weight: 700;
  margin-right: var(--sp-sm);
  min-width: 2.5rem;
  text-align: center;
}
.compact-info {
  flex: 1;
  text-align: left;
  min-width: 0;
}
.compact-name {
  font-size: var(--fs-base);
  font-weight: 600;
  margin-bottom: 0.2rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.compact-detail {
  opacity: 0.8;
  font-size: var(--fs-sm);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.compact-plays {
  font-size: var(--fs-sm);
  font-weight: 600;
  margin-left: var(--sp-sm);
  min-width: 3.5rem;
  text-align: right;
}

/* ----------  COMIC TOOLTIP  ---------- */
.chart-comic-tooltip {
  position: absolute;
  z-index: 9999;
  background: #fff;
  color: #222;
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
  font-size: var(--fs-xs);
  white-space: nowrap;
  box-shadow: 0 0.25rem 0.75rem rgba(0, 0, 0, 0.25);
  pointer-events: none;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.18s ease, transform 0.18s ease;
}
.chart-comic-tooltip.show {
  opacity: 1;
  transform: translateY(0);
}
.chart-comic-tooltip .tri {
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 6px 6px 0 6px;
  border-color: #fff transparent transparent transparent;
}