/* ============================================================
   JS Quiz — Modern Clean iOS-Inspired Style
   style.css
   ============================================================ */

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

/* ---------- Variables ---------- */
:root {
  --bg:          #f0f4ff;
  --bg-grad-1:   #667eea;
  --bg-grad-2:   #764ba2;
  --card:        #ffffff;
  --text-1:      #1a1a2e;
  --text-2:      #6b7280;
  --text-3:      #9ca3af;
  --primary:     #6c63ff;
  --primary-dk:  #5a52e0;
  --success:     #10b981;
  --success-bg:  #d1fae5;
  --danger:      #ef4444;
  --danger-bg:   #fee2e2;
  --option-bg:   #f8faff;
  --option-bdr:  #e5e7f5;
  --shadow-sm:   0 2px 8px rgba(108,99,255,0.08);
  --shadow-md:   0 8px 32px rgba(108,99,255,0.15);
  --shadow-lg:   0 20px 60px rgba(108,99,255,0.2);
  --radius-sm:   10px;
  --radius-md:   16px;
  --radius-lg:   24px;
  --radius-xl:   32px;
}

/* ---------- Base ---------- */
html { height: 100%; }

body {
  font-family: 'Nunito', sans-serif;
  min-height: 100vh;
  background: linear-gradient(135deg, var(--bg-grad-1) 0%, var(--bg-grad-2) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  position: relative;
  overflow-x: hidden;
}

/* Subtle background blobs */
body::before,
body::after {
  content: '';
  position: fixed;
  border-radius: 50%;
  opacity: 0.15;
  pointer-events: none;
  z-index: 0;
}

body::before {
  width: 500px; height: 500px;
  background: #fff;
  top: -150px; right: -150px;
  animation: float 8s ease-in-out infinite;
}

body::after {
  width: 400px; height: 400px;
  background: #fff;
  bottom: -120px; left: -120px;
  animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
  0%, 100% { transform: translateY(0) scale(1); }
  50%       { transform: translateY(20px) scale(1.05); }
}

/* ---------- Screens ---------- */
.screen {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  z-index: 10;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.screen.hidden {
  opacity: 0;
  pointer-events: none;
  transform: translateY(20px);
}

/* ---------- Card ---------- */
.card {
  background: var(--card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 480px;
  padding: 2.5rem 2rem;
  position: relative;
  animation: card-in 0.4s cubic-bezier(0.34, 1.3, 0.64, 1) both;
}

@keyframes card-in {
  from { opacity: 0; transform: translateY(30px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}

/* ---------- Start Screen ---------- */
.start-card { text-align: center; }

.start-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary), var(--bg-grad-2));
  color: #fff;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 0.35rem 1rem;
  border-radius: 20px;
  margin-bottom: 1.5rem;
}

.start-icon {
  font-size: 3.5rem;
  margin-bottom: 0.8rem;
  display: block;
  animation: pulse-icon 2s ease-in-out infinite;
}

@keyframes pulse-icon {
  0%, 100% { transform: scale(1); }
  50%       { transform: scale(1.1); }
}

.start-title {
  font-size: 2.6rem;
  font-weight: 900;
  color: var(--text-1);
  letter-spacing: -0.04em;
  margin-bottom: 0.6rem;
}

.start-sub {
  font-size: 0.95rem;
  color: var(--text-2);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  font-weight: 500;
}

.start-meta {
  display: flex;
  justify-content: center;
  gap: 0.6rem;
  margin-bottom: 2rem;
}

.meta-pill {
  background: var(--option-bg);
  border: 1px solid var(--option-bdr);
  color: var(--text-2);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.4rem 0.9rem;
  border-radius: 20px;
}

/* ---------- Quiz Screen ---------- */
.quiz-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.question-counter {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-2);
  letter-spacing: 0.03em;
}

.score-badge {
  background: linear-gradient(135deg, var(--primary), var(--bg-grad-2));
  color: #fff;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.3rem 0.8rem;
  border-radius: 20px;
  letter-spacing: 0.04em;
  transition: transform 0.2s cubic-bezier(0.34,1.56,0.64,1);
}

.score-badge.bump {
  transform: scale(1.2);
}

/* Progress bar */
.progress-wrap {
  height: 6px;
  background: var(--option-bg);
  border-radius: 3px;
  margin-bottom: 1.8rem;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--bg-grad-2));
  border-radius: 3px;
  width: 0%;
  transition: width 0.5s cubic-bezier(0.34, 1.2, 0.64, 1);
}

/* Question */
.question-wrap {
  margin-bottom: 1.5rem;
  position: relative;
}

.question-number {
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.question-text {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-1);
  line-height: 1.5;
  min-height: 3em;
}

/* Options */
.options-grid {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  margin-bottom: 1.5rem;
}

.option-btn {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  width: 100%;
  padding: 0.9rem 1.1rem;
  background: var(--option-bg);
  border: 2px solid var(--option-bdr);
  border-radius: var(--radius-md);
  cursor: pointer;
  text-align: left;
  transition: all 0.18s ease;
  font-family: 'Nunito', sans-serif;
  color: var(--text-1);
  font-size: 0.92rem;
  font-weight: 600;
  position: relative;
  overflow: hidden;
}

/* Letter badge */
.option-letter {
  width: 30px; height: 30px;
  border-radius: 8px;
  background: #fff;
  border: 2px solid var(--option-bdr);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--text-2);
  flex-shrink: 0;
  transition: all 0.18s;
}

.option-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: #f5f3ff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.option-btn:hover:not(:disabled) .option-letter {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* States */
.option-btn.correct {
  border-color: var(--success);
  background: var(--success-bg);
  transform: none;
}

.option-btn.correct .option-letter {
  background: var(--success);
  border-color: var(--success);
  color: #fff;
}

.option-btn.wrong {
  border-color: var(--danger);
  background: var(--danger-bg);
}

.option-btn.wrong .option-letter {
  background: var(--danger);
  border-color: var(--danger);
  color: #fff;
}

.option-btn:disabled { cursor: not-allowed; }

/* Result icon on option */
.option-result-icon {
  margin-left: auto;
  font-size: 1.1rem;
  flex-shrink: 0;
}

/* ---------- Buttons ---------- */
.btn {
  display: block;
  width: 100%;
  padding: 1rem;
  border-radius: var(--radius-md);
  border: none;
  font-family: 'Nunito', sans-serif;
  font-size: 1rem;
  font-weight: 800;
  cursor: pointer;
  transition: all 0.18s ease;
  letter-spacing: 0.01em;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--bg-grad-2));
  color: #fff;
  box-shadow: 0 4px 20px rgba(108,99,255,0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(108,99,255,0.45);
}

.btn-primary:active { transform: scale(0.98); }

.btn-next {
  background: linear-gradient(135deg, var(--primary), var(--bg-grad-2));
  color: #fff;
  box-shadow: 0 4px 20px rgba(108,99,255,0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  padding: 1rem;
  border-radius: var(--radius-md);
  border: none;
  font-family: 'Nunito', sans-serif;
  font-size: 1rem;
  font-weight: 800;
  cursor: pointer;
  transition: all 0.18s ease;
}

.btn-next:hover { transform: translateY(-2px); box-shadow: 0 8px 28px rgba(108,99,255,0.4); }
.btn-next:active { transform: scale(0.98); }

.btn-arrow { font-size: 1.1rem; transition: transform 0.18s; }
.btn-next:hover .btn-arrow { transform: translateX(4px); }

.btn-ghost {
  background: transparent;
  color: var(--text-2);
  margin-top: 0.5rem;
  font-weight: 700;
}

.btn-ghost:hover { color: var(--text-1); background: var(--option-bg); }

.hidden { display: none !important; }

/* ---------- Result Screen ---------- */
.result-card { text-align: center; }

.result-emoji {
  font-size: 3rem;
  display: block;
  margin-bottom: 0.6rem;
  animation: bounce-in 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

@keyframes bounce-in {
  from { opacity: 0; transform: scale(0.3); }
  to   { opacity: 1; transform: scale(1); }
}

.result-title {
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--text-1);
  letter-spacing: -0.03em;
  margin-bottom: 0.3rem;
}

.result-sub {
  font-size: 0.9rem;
  color: var(--text-2);
  font-weight: 600;
  margin-bottom: 1.5rem;
}

/* Score ring */
.score-ring-wrap {
  position: relative;
  width: 130px; height: 130px;
  margin: 0 auto 1.5rem;
}

.score-ring {
  width: 100%; height: 100%;
  transform: rotate(-90deg);
}

.ring-bg {
  fill: none;
  stroke: var(--option-bg);
  stroke-width: 10;
}

.ring-fill {
  fill: none;
  stroke: url(#ring-grad);
  stroke-width: 10;
  stroke-linecap: round;
  transition: stroke-dashoffset 1s cubic-bezier(0.34, 1.1, 0.64, 1);
}

.score-ring-text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
}

.score-num {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--text-1);
  letter-spacing: -0.04em;
}

.score-denom {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-3);
  margin-top: 0.8rem;
}

/* Stats row */
.result-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.6rem;
  margin-bottom: 1.5rem;
}

.stat-box {
  background: var(--option-bg);
  border: 1px solid var(--option-bdr);
  border-radius: var(--radius-md);
  padding: 0.9rem 0.5rem;
}

.stat-val {
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--text-1);
  letter-spacing: -0.03em;
}

.stat-label {
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-top: 0.2rem;
}

/* ---------- Footer ---------- */
.footer {
  position: fixed;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  color: var(--text-2);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  z-index: 20;
}

/* ---------- Responsive ---------- */
@media (max-width: 500px) {
  .card { padding: 2rem 1.5rem; }
  .start-title { font-size: 2.1rem; }
  .question-text { font-size: 1.05rem; }
  .option-btn { font-size: 0.87rem; padding: 0.8rem 0.9rem; }
}

@media (max-width: 360px) {
  .card { padding: 1.5rem 1.2rem; }
}