:root {
  --color-purple: #7c5cff;
  --color-pink: #ff5ca8;
  --color-orange: #ff9f5c;
  --color-blue: #3fb6ff;
  --color-teal: #2fd6b0;
  --color-yellow: #ffd23f;

  --color-success: #1fa971;
  --color-success-bg: #e4faf1;
  --color-error: #e0355b;
  --color-error-bg: #fdeaee;

  --color-ink: #2c2450;
  --color-ink-soft: #5c5480;
  --color-card-bg: rgba(255, 255, 255, 0.92);
  --color-card-border: rgba(255, 255, 255, 0.6);

  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;

  --shadow-soft: 0 10px 30px rgba(60, 30, 110, 0.18);
  --shadow-strong: 0 16px 40px rgba(60, 30, 110, 0.28);

  --font-display: 'Baloo 2', 'Nunito', sans-serif;
  --font-body: 'Nunito', sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-body);
  color: var(--color-ink);
  min-height: 100vh;
  background: linear-gradient(
    135deg,
    #6a5cff 0%,
    #a35cff 22%,
    #ff5ca8 48%,
    #ff9f5c 72%,
    #ffd23f 100%
  );
  background-attachment: fixed;
  overflow-x: hidden;
}

button {
  font-family: inherit;
}

select {
  font-family: inherit;
}


.app {
  position: relative;
  max-width: 1100px;
  margin: 0 auto;
  padding: clamp(16px, 4vw, 40px);
  display: flex;
  flex-direction: column;
  gap: clamp(16px, 2.5vw, 28px);
  min-height: 100vh;
}

/* Decorative floating background shapes */
.bg-decor {
  position: fixed;
  inset: 0;
  overflow: hidden;
  z-index: 0;
  pointer-events: none;
}

.floatie {
  position: absolute;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.16);
  filter: blur(2px);
  animation: floatUpDown 9s ease-in-out infinite;
}

.floatie-1 {
  width: 140px;
  height: 140px;
  top: 8%;
  left: 6%;
  animation-duration: 10s;
}

.floatie-2 {
  width: 90px;
  height: 90px;
  top: 65%;
  left: 12%;
  animation-duration: 7.5s;
  animation-delay: 1s;
}

.floatie-3 {
  width: 110px;
  height: 110px;
  top: 20%;
  right: 8%;
  animation-duration: 11s;
  animation-delay: 0.5s;
}

.floatie-4 {
  width: 70px;
  height: 70px;
  bottom: 10%;
  right: 18%;
  animation-duration: 8s;
  animation-delay: 2s;
}

@keyframes floatUpDown {
  0%,
  100% {
    transform: translateY(0) translateX(0);
  }
  50% {
    transform: translateY(-24px) translateX(10px);
  }
}

/* ---------- Header ---------- */
.app-header {
  position: relative;
  z-index: 1;
  text-align: center;
  animation: fadeInDown 0.6s ease both;
}

.app-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 5vw, 3rem);
  color: #ffffff;
  text-shadow: 0 4px 18px rgba(50, 20, 90, 0.35);
  margin: 0 0 8px;
  letter-spacing: 0.5px;
}

.title-slice {
  display: inline-block;
  animation: wiggle 3.2s ease-in-out infinite;
}

@keyframes wiggle {
  0%,
  100% {
    transform: rotate(0deg);
  }
  10% {
    transform: rotate(-12deg);
  }
  20% {
    transform: rotate(10deg);
  }
  30% {
    transform: rotate(0deg);
  }
}

.instructions {
  max-width: 640px;
  margin: 0 auto;
  color: rgba(255, 255, 255, 0.92);
  font-size: clamp(0.95rem, 1.6vw, 1.05rem);
  line-height: 1.5;
}

.instructions strong {
  color: #fff;
  font-weight: 800;
}

/* ---------- Stats bar ---------- */
.stats-bar {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
  animation: fadeInUp 0.6s ease 0.05s both;
}

.stat-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-soft);
  padding: 12px 22px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  min-width: 110px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.stat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-strong);
}

.stat-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-ink-soft);
}

.stat-value {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--color-purple);
  transition: transform 0.25s ease;
}

/* Pulse the score/level number whenever it changes */
.stat-value.bump {
  animation: bump 0.4s ease;
}

@keyframes bump {
  0% {
    transform: scale(1);
  }
  40% {
    transform: scale(1.35);
  }
  100% {
    transform: scale(1);
  }
}

.difficulty-card {
  min-width: 170px;
}

.difficulty-select {
  border: 2px solid rgba(124, 92, 255, 0.25);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-ink);
  background: #fff;
  cursor: pointer;
  transition: border-color 0.2s ease, transform 0.15s ease;
}

.difficulty-select:hover {
  border-color: var(--color-purple);
}

.difficulty-select:focus-visible {
  outline: 3px solid var(--color-blue);
  outline-offset: 2px;
}

/* ---------- Progress bar ---------- */
.progress-section {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  animation: fadeInUp 0.6s ease 0.1s both;
}

.progress-track {
  width: min(520px, 100%);
  height: 18px;
  background: rgba(255, 255, 255, 0.35);
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: 999px;
  overflow: hidden;
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.12);
}

.progress-fill {
  height: 100%;
  width: 0%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--color-teal), var(--color-blue), var(--color-purple));
  background-size: 200% 100%;
  transition: width 0.7s cubic-bezier(0.34, 1.56, 0.64, 1);
  animation: shimmer 3s linear infinite;
}

@keyframes shimmer {
  0% {
    background-position: 0% 0%;
  }
  100% {
    background-position: 200% 0%;
  }
}

.progress-caption {
  font-size: 0.82rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.9);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ---------- Main game area ---------- */
.game-area {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(16px, 3vw, 32px);
  align-items: stretch;
}

.circle-panel {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: clamp(16px, 3vw, 28px);
  animation: fadeIn 0.7s ease 0.1s both;
}

.circle-wrapper {
  position: relative;
  width: min(360px, 100%);
  aspect-ratio: 1 / 1;
}

.fraction-circle {
  width: 100%;
  height: 100%;
  display: block;
  overflow: visible;
}

/* Individual pie slice */
.slice {
  fill: #eef0fb;
  stroke: #ffffff;
  stroke-width: 3;
  cursor: pointer;
  transition: fill 0.45s ease, transform 0.3s ease, filter 0.3s ease;
  transform-origin: center;
  transform-box: fill-box;
}

.slice:hover {
  filter: brightness(1.06);
  transform: scale(1.02);
}

.slice:focus-visible {
  outline: 3px solid var(--color-blue);
  outline-offset: 2px;
}

.slice.shaded {
  animation: sliceFillPop 0.45s ease;
}

@keyframes sliceFillPop {
  0% {
    transform: scale(0.85);
  }
  55% {
    transform: scale(1.08);
  }
  100% {
    transform: scale(1);
  }
}

.slice.unshading {
  animation: sliceUnfillPop 0.35s ease;
}

@keyframes sliceUnfillPop {
  0% {
    transform: scale(1.08);
  }
  100% {
    transform: scale(1);
  }
}

.circle-center-label {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.2rem, 3vw, 1.6rem);
  color: var(--color-ink);
  background: #ffffff;
  border-radius: 50%;
  width: 30%;
  height: 30%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(60, 30, 110, 0.18);
  pointer-events: none;
  transition: transform 0.25s ease;
}

.circle-center-label.bump {
  animation: bump 0.4s ease;
}

/* ---------- Fraction / feedback cards ---------- */
.cards-panel {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.fraction-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: clamp(16px, 3vw, 22px);
  text-align: center;
  animation: fadeIn 0.7s ease both;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.fraction-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-strong);
}

.target-card {
  border-top: 5px solid var(--color-pink);
}

.current-card {
  border-top: 5px solid var(--color-blue);
}

.card-title {
  margin: 0 0 6px;
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--color-ink-soft);
}

.fraction-display {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 2.6rem);
  font-weight: 800;
  margin: 4px 0;
  color: var(--color-purple);
  transition: transform 0.3s ease;
}

.target-card .fraction-display {
  color: var(--color-pink);
}

.fraction-display.bump {
  animation: bump 0.4s ease;
}

.card-hint {
  margin: 4px 0 0;
  font-size: 0.8rem;
  color: var(--color-ink-soft);
}

/* Feedback message */
.feedback-message {
  min-height: 1.4em;
  margin: 0;
  padding: 10px 16px;
  border-radius: var(--radius-md);
  font-weight: 800;
  text-align: center;
  font-size: clamp(0.95rem, 2vw, 1.1rem);
  opacity: 0;
  transform: translateY(-6px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.feedback-message.visible {
  opacity: 1;
  transform: translateY(0);
}

.feedback-message.correct {
  background: var(--color-success-bg);
  color: var(--color-success);
  animation: popIn 0.4s ease;
}

.feedback-message.incorrect {
  background: var(--color-error-bg);
  color: var(--color-error);
  animation: shake 0.4s ease;
}

@keyframes popIn {
  0% {
    transform: scale(0.9);
  }
  60% {
    transform: scale(1.04);
  }
  100% {
    transform: scale(1);
  }
}

@keyframes shake {
  0%,
  100% {
    transform: translateX(0);
  }
  20% {
    transform: translateX(-6px);
  }
  40% {
    transform: translateX(6px);
  }
  60% {
    transform: translateX(-4px);
  }
  80% {
    transform: translateX(4px);
  }
}

/* ---------- Controls ---------- */
.controls {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  animation: fadeInUp 0.7s ease 0.15s both;
}

.btn {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.95rem;
  color: #fff;
  border: none;
  border-radius: 999px;
  padding: 13px 24px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 8px 18px rgba(60, 30, 110, 0.22);
  transition: transform 0.18s ease, box-shadow 0.18s ease, filter 0.18s ease, opacity 0.2s ease;
}

.btn-icon {
  font-size: 1.05rem;
  font-weight: 800;
  line-height: 1;
}

.btn:hover:not(:disabled) {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 12px 26px rgba(60, 30, 110, 0.3);
  filter: brightness(1.05);
}

.btn:active:not(:disabled) {
  transform: translateY(0) scale(0.97);
  box-shadow: 0 4px 10px rgba(60, 30, 110, 0.25);
}

.btn:focus-visible {
  outline: 3px solid #fff;
  outline-offset: 3px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  filter: grayscale(0.3);
  box-shadow: none;
  transform: none;
}

.btn-add {
  background: linear-gradient(135deg, var(--color-teal), #1fc6a4);
}

.btn-remove {
  background: linear-gradient(135deg, var(--color-orange), #ff7a45);
}

.btn-check {
  background: linear-gradient(135deg, var(--color-blue), #2f8fff);
}

.btn-next {
  background: linear-gradient(135deg, var(--color-purple), #5a3dff);
}

.btn-reset {
  background: linear-gradient(135deg, var(--color-pink), #e6397e);
}

/* Little click-pulse animation, toggled via JS by adding/removing a class */
.btn.clicked {
  animation: clickPulse 0.25s ease;
}

@keyframes clickPulse {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(0.92);
  }
  100% {
    transform: scale(1);
  }
}

/* ---------- Footer ---------- */
.app-footer {
  text-align: center;
  color: rgba(255, 255, 255, 0.75);
  font-size: 0.8rem;
  padding-top: 4px;
}

/* ---------- Confetti ---------- */
.confetti-container {
  position: fixed;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
  z-index: 50;
}

.confetti-piece {
  position: absolute;
  top: -20px;
  width: 10px;
  height: 16px;
  opacity: 0.95;
  animation-name: confettiFall;
  animation-timing-function: cubic-bezier(0.4, 0.1, 0.6, 0.9);
  animation-fill-mode: forwards;
}

@keyframes confettiFall {
  0% {
    transform: translateY(-10px) rotate(0deg);
    opacity: 1;
  }
  100% {
    transform: translateY(110vh) rotate(540deg);
    opacity: 0.9;
  }
}

/* ---------- Shared entrance animations ---------- */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- Responsive breakpoints ---------- */

/* Tablet */
@media (max-width: 860px) {
  .game-area {
    grid-template-columns: 1fr;
  }

  .circle-wrapper {
    width: min(320px, 80vw);
  }
}

/* Mobile */
@media (max-width: 520px) {
  .app-title {
    font-size: 1.7rem;
  }

  .stat-card {
    min-width: 90px;
    padding: 10px 16px;
  }

  .btn {
    flex: 1 1 calc(50% - 12px);
    justify-content: center;
    padding: 12px 14px;
    font-size: 0.85rem;
  }

  .controls {
    gap: 10px;
  }
}

/* Respect users who prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}