/*
  Number Ninja — App Styles
  Loaded after papupa.css; relies on --pa- design tokens.
  All selectors prefixed with nn- to avoid collisions.
  Dark dojo theme matching the ninja game concept.
*/

/* ── Leaderboard theme ───────────────────────────────────────────── */
:root {
  --lb-primary:   #9b5de5;
  --lb-secondary: #f15bb5;
  --lb-bg:        #f5f0ff;
  --lb-gold:      #fee440;
  --lb-silver:    #c0c0d0;
  --lb-bronze:    #cd7f32;
  --lb-row-hover: rgba(155, 93, 229, 0.08);
  --lb-row-me:    rgba(155, 93, 229, 0.15);

  /* Ninja palette */
  --nn-bg:        #0e0e1f;
  --nn-bg2:       #151528;
  --nn-panel:     #1c1c35;
  --nn-border:    rgba(155, 93, 229, 0.3);
  --nn-purple:    #9b5de5;
  --nn-pink:      #f15bb5;
  --nn-yellow:    #fee440;
  --nn-red:       #ff4d6d;
  --nn-green:     #06d6a0;
  --nn-blue:      #00bbf9;
  --nn-text:      #f0eeff;
  --nn-muted:     rgba(240, 238, 255, 0.5);
}

/* ── Page background ─────────────────────────────────────────────── */
body {
  background-color: var(--nn-bg);
  background-image:
    radial-gradient(ellipse at 15% 60%, rgba(155, 93, 229, 0.15) 0%, transparent 55%),
    radial-gradient(ellipse at 85% 20%, rgba(0, 187, 249, 0.10) 0%, transparent 50%);
}

/* ── Root container ──────────────────────────────────────────────── */
#nn-app {
  width: 100%;
  max-width: 560px;
  margin: 0 auto;
  font-family: var(--font-body);
  color: var(--nn-text);
  padding: var(--space-sm);
  box-sizing: border-box;
}

/* ═══════════════════════════════════════════════════════════════════
   WELCOME SCREEN
   ═══════════════════════════════════════════════════════════════════ */

.nn-welcome-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-md) 0 var(--space-xl);
  text-align: center;
}

.nn-logo-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.nn-logo-sprite {
  font-size: clamp(3rem, 12vw, 5rem);
  display: block;
  filter: drop-shadow(0 0 24px rgba(155, 93, 229, 0.8));
  animation: nn-float 3s ease-in-out infinite;
}

@keyframes nn-float {
  0%, 100% { transform: translateY(0) rotate(-4deg); }
  50%       { transform: translateY(-12px) rotate(4deg); }
}

.nn-title {
  font-family: var(--font-heading);
  font-size: clamp(2.4rem, 10vw, 4rem);
  font-weight: 800;
  letter-spacing: 3px;
  margin: 0;
  line-height: 1;
  background: linear-gradient(135deg, var(--nn-purple), var(--nn-pink), var(--nn-yellow));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nn-subtitle {
  color: var(--nn-muted);
  font-size: 0.9rem;
  font-weight: 700;
  margin: 0;
}

/* Level selection */
.nn-level-box {
  width: 100%;
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 20px;
  padding: var(--space-md) var(--space-md) var(--space-md);
  box-sizing: border-box;
}

.nn-level-box-header {
  font-size: 0.72rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--nn-purple);
  text-align: center;
  margin-bottom: var(--space-sm);
}

.nn-level-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}

.nn-level-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 12px 6px;
  background: rgba(255, 255, 255, 0.04);
  border: 2px solid transparent;
  border-radius: 14px;
  cursor: pointer;
  font-family: inherit;
  color: var(--nn-text);
  transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.nn-level-card:hover {
  border-color: var(--nn-purple);
  background: rgba(155, 93, 229, 0.12);
}

.nn-level-card.nn-active {
  border-color: var(--nn-purple);
  background: rgba(155, 93, 229, 0.18);
  box-shadow: 0 0 0 3px rgba(155, 93, 229, 0.22);
}

.nn-level-card-icon  { font-size: 1.5rem; }
.nn-level-card-name  { font-size: 0.88rem; font-weight: 800; }
.nn-level-card-desc  { font-size: 0.68rem; color: var(--nn-muted); text-align: center; font-weight: 700; }
.nn-level-card-time  { font-size: 0.65rem; color: var(--nn-yellow); font-weight: 900; margin-top: 2px; }

/* Info strip */
.nn-info-strip {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}

.nn-info-pill {
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 999px;
  padding: 5px 14px;
  font-size: 0.76rem;
  font-weight: 800;
  color: var(--nn-muted);
  display: flex;
  align-items: center;
  gap: 5px;
  white-space: nowrap;
}

.nn-info-pill span { color: var(--nn-yellow); }

/* Start button */
.nn-start-btn {
  padding: 14px 52px;
  font-size: 1.1rem;
  font-weight: 800;
  border: none;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--nn-purple), var(--nn-pink));
  color: #fff;
  cursor: pointer;
  box-shadow: 0 0 24px rgba(155, 93, 229, 0.5);
  transition: transform 0.15s ease, box-shadow 0.15s ease, opacity 0.15s ease;
  font-family: inherit;
}

.nn-start-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 36px rgba(155, 93, 229, 0.7);
}

.nn-start-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  box-shadow: none;
}

/* ═══════════════════════════════════════════════════════════════════
   GAME SCREEN
   ═══════════════════════════════════════════════════════════════════ */

.nn-game-container {
  display: flex;
  flex-direction: column;
  gap: 0;
  position: relative;
}

/* HUD */
.nn-hud {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 10px 12px;
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 16px 16px 0 0;
  flex-wrap: wrap;
}

.nn-hud-hearts {
  display: flex;
  gap: 3px;
  font-size: 1.25rem;
  line-height: 1;
}

.nn-heart {
  display: inline-block;
  transition: transform 0.2s ease, filter 0.2s ease;
}

.nn-heart--lost {
  filter: grayscale(1) opacity(0.3);
  transform: scale(0.8);
}

.nn-heart--shake {
  animation: nn-heart-shake 0.4s ease;
}

@keyframes nn-heart-shake {
  0%, 100% { transform: scale(1); }
  25% { transform: scale(1.4) rotate(-15deg); }
  75% { transform: scale(0.9) rotate(10deg); }
}

.nn-hud-score {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--nn-yellow);
  text-shadow: 0 0 12px rgba(254, 228, 64, 0.5);
}

.nn-hud-badge {
  font-size: 0.68rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 3px 10px;
  border-radius: 999px;
  border: 1px solid var(--nn-purple);
  color: var(--nn-purple);
  white-space: nowrap;
}

.nn-hud-progress {
  font-size: 0.76rem;
  font-weight: 800;
  color: var(--nn-muted);
  background: rgba(255, 255, 255, 0.06);
  border-radius: 999px;
  padding: 3px 10px;
}

.nn-pause-btn {
  background: transparent;
  border: 1px solid var(--nn-border);
  border-radius: 8px;
  color: var(--nn-text);
  font-size: 1rem;
  padding: 4px 10px;
  cursor: pointer;
  font-family: inherit;
  transition: border-color 0.15s ease, background 0.15s ease;
  line-height: 1;
}

.nn-pause-btn:hover {
  border-color: var(--nn-purple);
  background: rgba(155, 93, 229, 0.12);
}

/* Arena */
.nn-arena {
  position: relative;
  background: var(--nn-bg2);
  border-left: 1px solid var(--nn-border);
  border-right: 1px solid var(--nn-border);
  height: clamp(160px, 35vw, 220px);
  overflow: hidden;
}

/* Ground line */
.nn-arena::after {
  content: '';
  position: absolute;
  bottom: 36px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(155, 93, 229, 0.3), transparent);
  pointer-events: none;
}

/* Timer bar */
.nn-timer-track {
  position: absolute;
  top: 10px;
  left: 12px;
  right: 12px;
  height: 7px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 4px;
  overflow: hidden;
  z-index: 5;
}

.nn-timer-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--nn-green), #00d4a0);
  border-radius: 4px;
  transition: width 1s linear, background 0.5s ease;
}

.nn-timer-bar--amber { background: linear-gradient(90deg, #f59e0b, #fbbf24); }
.nn-timer-bar--red   { background: linear-gradient(90deg, var(--nn-red), #ff8c42); }

/* Wave label */
.nn-wave-label {
  position: absolute;
  top: 10px;
  right: 12px;
  font-size: 0.72rem;
  font-weight: 800;
  color: var(--nn-muted);
  z-index: 5;
}

/* Ninja */
.nn-ninja {
  position: absolute;
  bottom: 38px;
  left: 16px;
  font-size: clamp(2.2rem, 8vw, 3.2rem);
  line-height: 1;
  filter: drop-shadow(0 0 10px rgba(155, 93, 229, 0.6));
  z-index: 4;
  user-select: none;
  transition: filter 0.15s ease;
}

.nn-ninja--attacking {
  animation: nn-ninja-attack 0.4s ease;
}

.nn-ninja--hit {
  animation: nn-ninja-hit 0.5s ease;
}

@keyframes nn-ninja-attack {
  0%   { transform: translateX(0) scaleX(1); }
  30%  { transform: translateX(18px) scaleX(1.15); }
  60%  { transform: translateX(6px) scaleX(0.9); }
  100% { transform: translateX(0) scaleX(1); }
}

@keyframes nn-ninja-hit {
  0%, 100% { transform: translateX(0); filter: drop-shadow(0 0 10px rgba(155, 93, 229, 0.6)); }
  20%  { transform: translateX(-10px); filter: drop-shadow(0 0 18px rgba(255, 77, 109, 0.9)); }
  40%  { transform: translateX(6px); }
  60%  { transform: translateX(-5px); filter: drop-shadow(0 0 18px rgba(255, 77, 109, 0.9)); }
}

/* Monster */
.nn-monster {
  position: absolute;
  bottom: 38px;
  right: 16px;
  font-size: clamp(1.8rem, 7vw, 2.8rem);
  line-height: 1;
  z-index: 3;
  user-select: none;
  filter: drop-shadow(0 0 8px rgba(255, 77, 109, 0.4));
}

.nn-monster.nn-monster--active {
  animation: nn-monster-march var(--nn-time, 15s) linear forwards;
}

@keyframes nn-monster-march {
  0%   { transform: translateX(0); }
  100% { transform: translateX(-360px); }
}

.nn-monster.nn-monster--killed {
  animation: nn-monster-killed 0.55s ease forwards;
}

.nn-monster.nn-monster--attacking {
  animation: nn-monster-attack 0.45s ease;
}

@keyframes nn-monster-killed {
  0%   { transform: scale(1); filter: drop-shadow(0 0 8px rgba(255, 77, 109, 0.4)); }
  25%  { transform: translateX(40px) scale(1.3); filter: drop-shadow(0 0 28px rgba(254, 228, 64, 1)); }
  70%  { transform: translateX(120px) scale(0.7) rotate(25deg); opacity: 0.8; }
  100% { transform: translateX(220px) scale(0.2) rotate(45deg); opacity: 0; }
}

@keyframes nn-monster-attack {
  0%   { transform: translateX(0) scale(1); }
  30%  { transform: translateX(-20px) scale(1.2); }
  60%  { transform: translateX(-8px); }
  100% { transform: translateX(0) scale(1); }
}

/* FX: slash + score pop */
.nn-slash {
  position: absolute;
  bottom: 52px;
  left: 22%;
  font-size: 1.8rem;
  z-index: 8;
  pointer-events: none;
  animation: nn-slash 0.45s ease forwards;
}

@keyframes nn-slash {
  0%   { opacity: 1; transform: scale(0.5) rotate(-20deg); }
  40%  { opacity: 1; transform: scale(1.4) rotate(10deg); }
  100% { opacity: 0; transform: scale(1.8) rotate(30deg) translateY(-18px); }
}

.nn-score-pop {
  position: absolute;
  bottom: 45%;
  left: 20%;
  font-size: 1.5rem;
  font-weight: 800;
  pointer-events: none;
  z-index: 8;
  animation: nn-score-pop 0.85s ease forwards;
}

.nn-score-pop--good   { color: var(--nn-green); }
.nn-score-pop--bad    { color: var(--nn-red); }
.nn-score-pop--bonus  { color: var(--nn-yellow); }

@keyframes nn-score-pop {
  0%   { opacity: 1; transform: translateY(0) scale(0.8); }
  30%  { transform: translateY(-18px) scale(1.2); }
  100% { opacity: 0; transform: translateY(-60px) scale(0.9); }
}

/* Pause overlay */
.nn-pause-overlay {
  display: none;
  position: absolute;
  inset: 0;
  z-index: 20;
  background: rgba(13, 13, 31, 0.88);
  backdrop-filter: blur(6px);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 16px;
  text-align: center;
  border-radius: 0;
}

.nn-pause-overlay.nn-pause-overlay--show {
  display: flex;
}

.nn-pause-title {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: 3px;
  color: var(--nn-yellow);
  text-shadow: 0 0 20px rgba(254, 228, 64, 0.5);
}

.nn-pause-hint {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--nn-muted);
}

.nn-resume-btn {
  padding: 12px 40px;
  font-size: 1.05rem;
  font-weight: 800;
  border: none;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--nn-purple), var(--nn-pink));
  color: #fff;
  cursor: pointer;
  font-family: inherit;
  box-shadow: 0 0 20px rgba(155, 93, 229, 0.5);
  transition: transform 0.15s ease;
}

.nn-resume-btn:hover { transform: translateY(-2px); }

/* Equation panel */
.nn-equation-panel {
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-top: none;
  border-radius: 0 0 16px 16px;
  padding: 14px 16px 18px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.nn-equation {
  font-size: clamp(1.8rem, 7vw, 2.8rem);
  font-weight: 800;
  letter-spacing: 3px;
  color: var(--nn-text);
  text-shadow: 0 0 16px rgba(155, 93, 229, 0.4);
  text-align: center;
  min-height: 1.2em;
}

.nn-equation.nn-equation--correct { animation: nn-flash-green 0.35s ease; }
.nn-equation.nn-equation--wrong   { animation: nn-flash-red   0.35s ease; }

@keyframes nn-flash-green {
  0%, 100% { color: var(--nn-text); }
  50% { color: var(--nn-green); text-shadow: 0 0 20px rgba(6, 214, 160, 0.8); }
}

@keyframes nn-flash-red {
  0%, 100% { color: var(--nn-text); }
  50% { color: var(--nn-red); text-shadow: 0 0 20px rgba(255, 77, 109, 0.8); }
}

/* Input row + numpad */
.nn-input-row {
  display: flex;
  gap: 10px;
  align-items: center;
  width: 100%;
  max-width: 340px;
}

.nn-answer-input {
  flex: 1;
  min-width: 0;  
  max-width: 180px;
  font-size: 1.4rem;
  font-weight: 800;
  text-align: center;
  background: rgba(255, 255, 255, 0.06);
  border: 2px solid var(--nn-border);
  border-radius: 12px;
  color: var(--nn-text);
  padding: 9px 10px;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  font-family: inherit;
  -moz-appearance: textfield;
}

.nn-answer-input::-webkit-inner-spin-button,
.nn-answer-input::-webkit-outer-spin-button { -webkit-appearance: none; }

.nn-answer-input:focus {
  border-color: var(--nn-purple);
  box-shadow: 0 0 0 3px rgba(155, 93, 229, 0.2);
}

.nn-answer-input--correct {
  border-color: var(--nn-green);
  box-shadow: 0 0 0 3px rgba(6, 214, 160, 0.2);
}

.nn-answer-input--wrong {
  border-color: var(--nn-red);
  box-shadow: 0 0 0 3px rgba(255, 77, 109, 0.2);
  animation: nn-input-shake 0.35s ease;
}

@keyframes nn-input-shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-8px); }
  40% { transform: translateX(8px); }
  60% { transform: translateX(-5px); }
  80% { transform: translateX(5px); }
}

.nn-answer-input:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.nn-submit-btn {
  flex-shrink: 0;
  font-size: 1rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--nn-purple), var(--nn-pink));
  color: #fff;
  border: none;
  border-radius: 12px;
  padding: 11px 16px;
  cursor: pointer;
  font-family: inherit;
  transition: transform 0.15s ease, opacity 0.15s ease;
  white-space: nowrap;
  box-shadow: 0 0 14px rgba(155, 93, 229, 0.4);
}

.nn-submit-btn:hover:not(:disabled) { transform: translateY(-1px); }
.nn-submit-btn:disabled { opacity: 0.45; cursor: not-allowed; }

/* Numpad */
.nn-numpad {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 5px;
  width: 100%;
  max-width: 168px;
}

.nn-numpad-btn {
  font-size: 0.78rem;
  font-weight: 800;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--nn-border);
  border-radius: 8px;
  color: var(--nn-text);
  padding: 8px 5px;
  cursor: pointer;
  font-family: inherit;
  transition: background 0.1s ease, transform 0.1s ease;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.nn-numpad-btn:hover:not(:disabled) {
  background: rgba(155, 93, 229, 0.18);
}

.nn-numpad-btn:active:not(:disabled) {
  transform: scale(0.94);
  background: rgba(155, 93, 229, 0.28);
}

.nn-numpad-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.nn-numpad-btn--backspace { color: var(--nn-red); }
.nn-numpad-btn--submit    { background: linear-gradient(135deg, rgba(155, 93, 229, 0.3), rgba(241, 91, 181, 0.3)); color: var(--nn-yellow); }

.nn-hint-text {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--nn-muted);
  text-align: center;
}

.nn-hint-text kbd {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 4px;
  padding: 1px 5px;
  font-family: inherit;
  font-size: 0.68rem;
}

/* Feedback banner */
.nn-feedback {
  position: relative;
  width: 100%;
  max-width: 340px;
  padding: 8px 14px;
  font-size: 0.85rem;
  font-weight: 700;
  text-align: center;
  border-radius: 10px;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease;
  pointer-events: none;
}

.nn-feedback.nn-feedback--show {
  opacity: 1;
  transform: translateY(0);
}

.nn-feedback--correct { background: rgba(6, 214, 160, 0.15); color: var(--nn-green); border: 1px solid rgba(6, 214, 160, 0.3); }
.nn-feedback--wrong   { background: rgba(255, 77, 109, 0.15); color: var(--nn-red);   border: 1px solid rgba(255, 77, 109, 0.3); }
.nn-feedback--timeout { background: rgba(254, 228, 64, 0.12); color: var(--nn-yellow); border: 1px solid rgba(254, 228, 64, 0.3); }

/* Streak bonus popup */
.nn-streak-popup {
  position: fixed;
  top: 40%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.6);
  background: linear-gradient(135deg, var(--nn-yellow), #ffb703);
  color: #1a1a2e;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 1.05rem;
  font-weight: 900;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s ease, transform 0.15s ease;
  white-space: nowrap;
  z-index: 9999;
}

.nn-streak-popup.nn-streak-popup--show {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
  animation: nn-streak-pop 1.2s ease forwards;
}

@keyframes nn-streak-pop {
  0%   { opacity: 1; transform: translate(-50%, -50%) scale(1); }
  60%  { opacity: 1; transform: translate(-50%, -70%) scale(1.08); }
  100% { opacity: 0; transform: translate(-50%, -90%) scale(0.9); }
}

/* ═══════════════════════════════════════════════════════════════════
   RESULT SCREEN
   ═══════════════════════════════════════════════════════════════════ */

.nn-result-screen {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.nn-result-scroll {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.nn-result-header {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
}

.nn-result-trophy {
  font-size: clamp(3rem, 12vw, 4.5rem);
  display: block;
  filter: drop-shadow(0 0 20px rgba(254, 228, 64, 0.6));
  animation: nn-pop-in 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

@keyframes nn-pop-in {
  0% { opacity: 0; transform: scale(0.5); }
  100% { opacity: 1; transform: scale(1); }
}

/* Stars */
.nn-stars-display {
  display: flex;
  gap: 8px;
  justify-content: center;
}

.nn-star {
  font-size: clamp(1.8rem, 7vw, 2.6rem);
  line-height: 1;
  filter: grayscale(1) opacity(0.3);
  transition: filter 0.3s ease, transform 0.3s ease;
}

.nn-star--earned {
  filter: none;
  transform: scale(1.1);
  animation: nn-star-pop 0.4s cubic-bezier(0.34, 1.6, 0.64, 1);
  text-shadow: 0 0 16px rgba(254, 228, 64, 0.6);
}

@keyframes nn-star-pop {
  0%   { transform: scale(0.4) rotate(-25deg); }
  100% { transform: scale(1.1) rotate(0); }
}

.nn-result-heading {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 5vw, 2.2rem);
  font-weight: 800;
  margin: 0;
  line-height: 1.2;
}

.nn-result-heading--win  { color: var(--nn-green); }
.nn-result-heading--loss { color: var(--nn-muted); }

.nn-result-subheading {
  font-size: 0.88rem;
  color: var(--nn-muted);
  font-weight: 700;
  margin: 0;
}

/* Metrics */
.nn-metrics-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-sm);
}

.nn-metric-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 14px;
  padding: 14px 8px;
}

.nn-metric-icon  { font-size: 1.4rem; }
.nn-metric-value { font-size: 1.5rem; font-weight: 800; color: var(--nn-yellow); line-height: 1; }
.nn-metric-value--text { font-size: 0.95rem; color: var(--nn-text); }
.nn-metric-label { font-size: 0.62rem; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; color: var(--nn-muted); }

/* Grade card */
.nn-grade-card {
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 16px;
  padding: var(--space-md);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.nn-grade-emoji { font-size: 2rem; }
.nn-grade-name  { font-size: 1.2rem; font-weight: 800; letter-spacing: 1px; }
.nn-grade-desc  { font-size: 0.82rem; font-weight: 700; color: var(--nn-muted); }

/* Play-again card */
.nn-play-again-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  background: rgba(155, 93, 229, 0.08);
  border: 2px solid rgba(155, 93, 229, 0.3);
  border-radius: 16px;
  padding: var(--space-md);
  cursor: pointer;
  font-family: inherit;
  width: 100%;
  box-sizing: border-box;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.nn-play-again-card:hover:not(:disabled) {
  border-color: var(--nn-purple);
  box-shadow: 0 0 20px rgba(155, 93, 229, 0.2);
}

.nn-play-again-card:disabled { opacity: 0.6; cursor: not-allowed; }

.nn-play-again-icon  { font-size: 1.6rem; }
.nn-play-again-title { font-size: 1.05rem; font-weight: 800; color: var(--nn-purple); }
.nn-play-again-note  { font-size: 0.78rem; color: var(--nn-muted); }

/* Sign-in prompt */
.nn-signin-prompt {
  text-align: center;
  font-size: 0.84rem;
  color: var(--nn-muted);
  margin: 0;
  font-weight: 700;
}

.nn-signin-link {
  background: none;
  border: none;
  color: var(--nn-purple);
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  font-size: inherit;
  padding: 0;
  text-decoration: underline;
}

/* Leaderboard card */
.nn-leaderboard-card {
  background: var(--nn-panel);
  border: 1px solid var(--nn-border);
  border-radius: 16px;
  padding: var(--space-md);
}

.nn-leaderboard-card-header {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  margin-bottom: var(--space-sm);
  font-size: 1.15rem;
}

.nn-leaderboard-title {
  font-size: 1rem;
  font-weight: 700;
  margin: 0;
  color: var(--nn-text);
}

.nn-leaderboard-message {
  display: block;
  font-size: 0.84rem;
  color: var(--nn-muted);
  text-align: center;
  margin: 0;
  font-weight: 700;
}

.nn-leaderboard-message--link {
  background: none;
  border: none;
  color: var(--nn-purple);
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  font-size: 0.9rem;
  padding: 0;
  text-decoration: none;
  transition: opacity 0.15s ease;
}

.nn-leaderboard-message--link:hover { opacity: 0.8; }

/* Result footer */
.nn-result-footer {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
}

.nn-footer-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 12px;
  border-radius: 12px;
  font-size: 0.9rem;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: opacity 0.15s ease, transform 0.15s ease;
}

.nn-footer-btn:hover:not(:disabled) {
  opacity: 0.9;
  transform: translateY(-1px);
}

.nn-footer-btn--play  { background: linear-gradient(135deg, var(--nn-purple), var(--nn-pink)); color: #fff; }
.nn-footer-btn--games { background: rgba(255, 255, 255, 0.08); color: var(--nn-text); border: 1px solid var(--nn-border); }

/* ═══════════════════════════════════════════════════════════════════
   RESPONSIVE — MOBILE  (≤ 480px)
   ═══════════════════════════════════════════════════════════════════ */

@media (max-width: 480px) {
  #nn-app {
    padding: var(--space-xs);
  }

  .nn-level-cards {
    gap: 6px;
  }

  .nn-level-card {
    padding: 10px 4px;
  }

  .nn-level-card-icon { font-size: 1.3rem; }
  .nn-level-card-name { font-size: 0.78rem; }
  .nn-level-card-desc { font-size: 0.62rem; }

  .nn-start-btn {
    padding: 12px 36px;
    font-size: 1rem;
  }

  .nn-hud {
    gap: 6px;
    padding: 8px 10px;
  }

  .nn-hud-hearts { font-size: 1.1rem; }
  .nn-hud-score  { font-size: 1rem; }

  .nn-numpad {
    max-width: 156px;
    gap: 4px;
  }

  .nn-numpad-btn {
    padding: 7px 4px;
    font-size: 0.69rem;
  }

  .nn-metrics-row { gap: 8px; }
  .nn-metric-value { font-size: 1.25rem; }

  .nn-result-footer { flex-direction: column; }

  .nn-star { font-size: 1.6rem; }
}

/* ═══════════════════════════════════════════════════════════════════
   RESPONSIVE — TABLET  (481px – 768px)
   ═══════════════════════════════════════════════════════════════════ */

@media (min-width: 481px) and (max-width: 768px) {
  .nn-numpad-btn {
    padding: 10px 5px;
  }

  .nn-footer-btn { padding: 14px; }
  .nn-star { font-size: 2.2rem; }
}