/* ============================================================
   ATLAS ABC — styles.css
   Playful, pastel, kid-friendly educational geography explorer
   ============================================================ */

/* ── Custom Properties ──────────────────────────────────────── */
:root {
  --sky:        #E8F4FD;
  --blue:       #4EAEE5;
  --blue-deep:  #2B8EC4;
  --yellow:     #FFD94A;
  --yellow-dk:  #F0B800;
  --mint:       #6DD5B0;
  --mint-dk:    #3DBE8F;
  --coral:      #FF7F5C;
  --coral-dk:   #E85E38;
  --lavender:   #C3B1E1;
  --lav-dk:     #9B7FD1;
  --cream:      #FFFBEF;
  --white:      #FFFFFF;
  --ink:        #2D2B4E;
  --ink-light:  #5C5A7A;
  --shadow:     rgba(45,43,78,0.12);
  --shadow-md:  rgba(45,43,78,0.18);

  --font-display: 'Fredoka One', cursive;
  --font-body:    'Nunito', sans-serif;

  --radius-sm:  12px;
  --radius-md:  20px;
  --radius-lg:  32px;
  --radius-xl:  48px;

  --transition: 0.22s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: linear-gradient(160deg, #D6EDFF 0%, #EEF9FF 35%, #FFF8E7 70%, #FFE8F0 100%);
  min-height: 100vh;
  color: var(--ink);
  overflow-x: hidden;
}

/* ── Utility ────────────────────────────────────────────────── */
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ── HEADER ─────────────────────────────────────────────────── */
.site-header {
  background: rgba(255,255,255,0.96);
  box-shadow: 0 8px 24px rgba(45,43,78,0.1);
  padding: 0;
  position: sticky;
  top: 0;
  z-index: 120;
  border-bottom: 1px solid rgba(78,174,229,0.16);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 76px;
  width: min(1240px, calc(100% - 48px));
  margin: 0 auto;
  padding: 10px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 13px;
  text-decoration: none;
  min-width: max-content;
}

.brand-icon {
  display: block;
  width: clamp(44px, 5vw, 62px);
  height: clamp(44px, 5vw, 62px);
  object-fit: contain;
  flex: 0 0 auto;
  filter: drop-shadow(0 4px 9px rgba(43,142,196,0.22));
}

.brand-title {
  font-family: var(--font-display);
  font-size: clamp(1.665rem, 3.42vw, 2.61rem);
  letter-spacing: 0;
  line-height: 0.92;
  margin: 0;
  white-space: nowrap;
  text-shadow: 0 4px 9px rgba(45,43,78,0.12);
}

.brand-title .atlas { color: #36A5EE; }
.brand-title .a { color: #54C988; }
.brand-title .b { color: #FF5D93; }
.brand-title .c { color: #FFBE2E; }

.brand-subtitle {
  font-size: clamp(0.78rem, 1.35vw, 1.02rem);
  font-weight: 800;
  color: #222853;
  margin-top: 5px;
  letter-spacing: 0;
  line-height: 1.1;
  white-space: nowrap;
}

/* ── PAGE LAYOUT ─────────────────────────────────────────────── */
.page-layout {
  width: 100%;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  align-items: start;
  gap: 24px;
  transition: grid-template-columns 0.24s ease;
}

.content-column {
  min-width: 0;
}

body.detail-panel-open .page-layout {
  grid-template-columns: minmax(0, 1fr) clamp(380px, 30vw, 440px);
  padding-right: 24px;
}

body.detail-panel-open .content-column {
  min-width: 0;
}

/* ── Alphabet Navigation ─────────────────────────────────────── */
.alphabet-section {
  position: sticky;
  top: 76px;
  z-index: 110;
  width: 100%;
  margin: 0;
  padding: 11px 24px 13px;
  background: rgba(248,252,255,0.96);
  border-bottom: 1px solid rgba(78,174,229,0.14);
  box-shadow: 0 4px 12px rgba(45,43,78,0.06);
}

.alphabet-helper {
  margin: 0 auto 6px;
  width: min(1560px, 100%);
  text-align: center;
  font-family: var(--font-display);
  color: #20285F;
  font-size: clamp(0.88rem, 1.4vw, 1.02rem);
  line-height: 1.15;
}

.alpha-nav {
  width: min(1560px, 100%);
  margin: 0 auto;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
  padding: 10px 8px 13px;
}
.alpha-nav::-webkit-scrollbar { display: none; }

.alpha-strip {
  display: flex;
  gap: 12px;
  min-width: max-content;
  padding: 0 8px;
  justify-content: center;
  align-items: center;
}

/* On small screens, left-align for scrollability */
@media (max-width: 860px) {
  .alpha-strip { justify-content: flex-start; }
}

.alpha-btn {
  font-family: var(--font-display);
  font-size: 1.08rem;
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 16px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.14s ease, box-shadow 0.14s ease, filter 0.14s ease, outline-color 0.14s ease;
  position: relative;
  outline: none;
  font-weight: 400;
  color: #20285F;
  box-shadow:
    inset 0 -4px rgba(45,43,78,0.12),
    0 3px 6px rgba(45,43,78,0.12);
  flex-shrink: 0;
}

.alpha-btn:hover {
  transform: translateY(-1px);
  box-shadow:
    inset 0 -4px rgba(45,43,78,0.12),
    0 4px 8px rgba(45,43,78,0.14);
  filter: saturate(1.06);
  z-index: 2;
}

.alpha-btn:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
}

.alpha-btn.active {
  transform: translateY(-2px) scale(1.18);
  box-shadow:
    inset 0 -4px rgba(45,43,78,0.12),
    0 4px 8px rgba(45,43,78,0.14);
  filter: saturate(1.12);
  outline: 3px solid #fff;
  outline-offset: -6px;
  z-index: 3;
  animation: letterPop 0.34s ease-out;
}

@keyframes letterPop {
  0%   { transform: translateY(0) scale(1); }
  65%  { transform: translateY(-3px) scale(1.22); }
  100% { transform: translateY(-2px) scale(1.18); }
}

/* Letter color cycling */
.alpha-btn:nth-child(7n+1)  { background: #FFD85C; }
.alpha-btn:nth-child(7n+2)  { background: #FF93B6; }
.alpha-btn:nth-child(7n+3)  { background: #8BE1C2; }
.alpha-btn:nth-child(7n+4)  { background: #8FD2FF; }
.alpha-btn:nth-child(7n+5)  { background: #C8B9EA; }
.alpha-btn:nth-child(7n+6)  { background: #FFA06B; }
.alpha-btn:nth-child(7n+7)  { background: #91DFC4; }


/* ── REWARD BAR ─────────────────────────────────────────────── */
.reward-bar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  margin-left: auto;
  padding: 0;
}

.reward-stats {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 7px;
}

.reward-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  min-height: 30px;
  padding: 5px 10px;
  border-radius: var(--radius-xl);
  background: #fff;
  border: 1px solid rgba(78,174,229,0.12);
  box-shadow: 0 2px 0 rgba(45,43,78,0.06), 0 5px 12px rgba(45,43,78,0.08);
  color: var(--ink-light);
  font-size: 0.78rem;
  font-weight: 900;
}

.reward-chip strong {
  color: var(--ink);
  font-size: 0.9rem;
}

.passport-profile {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: 0 0 auto;
}

.passport-open {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 1rem;
  height: 52px;
  padding: 0 18px;
  border: 1px solid rgba(20,40,80,0.08);
  border-radius: 999px;
  background: #fff;
  color: #1D2555;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(20,40,80,0.06);
  transition: transform 0.15s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.15s ease;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.passport-open:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(20,40,80,0.1);
}

.passport-open:active {
  transform: translateY(1px) scale(0.98);
  box-shadow: 0 1px 5px rgba(20,40,80,0.08);
}

.passport-icon {
  width: 26px;
  height: 26px;
  object-fit: contain;
  flex: 0 0 auto;
}

.explorer-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  flex: 0 0 auto;
  box-shadow: 0 2px 8px rgba(20,40,80,0.1);
}

.reward-feedback-layer {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 500;
  overflow: hidden;
}

.xp-float,
.stamp-pop {
  position: fixed;
  left: 50%;
  top: 84px;
  transform: translateX(-50%);
  border-radius: var(--radius-xl);
  font-family: var(--font-display);
  font-size: 1rem;
  color: #6B4200;
  background: linear-gradient(135deg, #FFF5B8, var(--yellow));
  border: 3px solid white;
  box-shadow: 0 6px 0 var(--yellow-dk), 0 14px 28px rgba(45,43,78,0.2);
  padding: 10px 16px;
  animation: rewardFloat 1.15s ease-out forwards;
}

.stamp-pop {
  top: 132px;
  color: #0A5C3C;
  background: linear-gradient(135deg, #E6FFF4, #B8EDD4);
  box-shadow: 0 6px 0 var(--mint-dk), 0 14px 28px rgba(45,43,78,0.2);
  animation-name: stampPop;
}

@keyframes rewardFloat {
  0% { opacity: 0; transform: translate(-50%, 12px) scale(0.75); }
  20% { opacity: 1; transform: translate(-50%, 0) scale(1.08); }
  100% { opacity: 0; transform: translate(-50%, -54px) scale(1); }
}

@keyframes stampPop {
  0% { opacity: 0; transform: translate(-50%, 12px) scale(0.5) rotate(-8deg); }
  30% { opacity: 1; transform: translate(-50%, 0) scale(1.12) rotate(4deg); }
  100% { opacity: 0; transform: translate(-50%, -42px) scale(1) rotate(0deg); }
}

/* ── PASSPORT ───────────────────────────────────────────────── */
.passport-overlay {
  position: fixed;
  inset: 0;
  z-index: 320;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(45,43,78,0.62);
  backdrop-filter: blur(8px);
  animation: overlayIn 0.22s ease both;
}

.passport-overlay[hidden] { display: none !important; }

.passport-panel {
  position: relative;
  width: min(760px, 96vw);
  max-height: min(90vh, 760px);
  overflow-y: auto;
  border-radius: 28px;
  padding: 26px;
  background:
    linear-gradient(90deg, rgba(45,43,78,0.08) 0 16px, transparent 16px),
    linear-gradient(160deg, #FFFBEF 0%, #ffffff 45%, #F0F9FF 100%);
  border: 3px solid rgba(255,255,255,0.9);
  box-shadow: 0 14px 0 rgba(195,177,225,0.34), 0 28px 70px rgba(45,43,78,0.34);
  animation: challengePop 0.34s cubic-bezier(0.34,1.56,0.64,1) both;
}

.passport-close {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 38px;
  height: 38px;
  border: none;
  border-radius: 50%;
  background: white;
  color: var(--ink);
  font-weight: 900;
  cursor: pointer;
  box-shadow: 0 3px 0 rgba(45,43,78,0.12), 0 6px 14px var(--shadow);
}

.passport-cover {
  display: flex;
  align-items: center;
  gap: 14px;
  padding-right: 46px;
  margin-bottom: 22px;
}

.passport-mark {
  width: 58px;
  height: 58px;
  object-fit: contain;
  border-radius: 18px;
  background: rgba(195,177,225,0.22);
  box-shadow: 0 5px 0 rgba(155,127,209,0.55), 0 10px 20px rgba(195,177,225,0.28);
  padding: 9px;
}

.passport-title,
.passport-section h3 {
  font-family: var(--font-display);
  color: var(--ink);
}

.passport-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1;
}

.passport-subtitle {
  margin-top: 4px;
  color: var(--ink-light);
  font-weight: 800;
}

.passport-section {
  margin-top: 20px;
}

.passport-section h3 {
  margin-bottom: 10px;
  font-size: 1.05rem;
}

.passport-badges,
.stamp-grid,
.passport-discoveries {
  display: grid;
  gap: 10px;
}

.passport-badges {
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
}

.passport-badge,
.passport-discovery,
.passport-empty {
  border-radius: 16px;
  padding: 12px;
  background: rgba(255,255,255,0.78);
  border: 2px solid rgba(78,174,229,0.12);
  box-shadow: 0 4px 12px var(--shadow);
  font-weight: 800;
}

.passport-badge strong,
.passport-discovery strong {
  display: block;
  color: var(--ink);
}

.passport-badge span,
.passport-discovery span {
  display: block;
  margin-top: 3px;
  color: var(--ink-light);
  font-size: 0.82rem;
}

.stamp-grid {
  grid-template-columns: repeat(auto-fill, minmax(94px, 1fr));
}

.passport-stamp,
.passport-empty {
  min-height: 84px;
  display: grid;
  place-items: center;
  text-align: center;
  border-radius: 18px;
  border: 3px dashed rgba(45,43,78,0.14);
}

.passport-stamp {
  background: linear-gradient(135deg, #E6FFF4, #FFF9D9);
  border-color: rgba(88,213,176,0.48);
  color: #0A5C3C;
  animation: passportStampIn 0.32s cubic-bezier(0.34,1.56,0.64,1) both;
}

@keyframes passportStampIn {
  0% { transform: scale(0.72) rotate(-8deg); opacity: 0; }
  100% { transform: scale(1) rotate(0deg); opacity: 1; }
}

.passport-empty {
  color: var(--ink-light);
  background: rgba(255,255,255,0.42);
}

.passport-discoveries {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

/* ── HERO ───────────────────────────────────────────────────── */
.hero-section {
  width: min(1560px, calc(100% - 48px));
  margin: 14px auto 20px;
  aspect-ratio: 1930 / 459;
  position: relative;
  overflow: hidden;
  background: transparent;
  border: 0;
  padding: 0;
  border-radius: 22px;
  box-shadow: 0 5px 16px rgba(45,43,78,0.07);
}

.hero-section > img {
  display: block;
  width: 102.75%;
  height: auto;
  max-width: none;
  position: absolute;
  top: -38.34%;
  left: -1.37%;
}

/* ── MAIN CONTENT ───────────────────────────────────────────── */
.main-content {
  max-width: 1560px;
  margin: 0 auto;
  padding: 0 24px 60px;
}

/* ── Category Filters ────────────────────────────────────────── */
.filter-section {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.filter-label {
  font-weight: 800;
  font-size: 0.9rem;
  color: var(--ink-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  white-space: nowrap;
}

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

.filter-btn {
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 10px 28px;
  border-radius: var(--radius-xl);
  border: 1px solid rgba(78,174,229,0.1);
  cursor: pointer;
  transition: var(--transition);
  outline: none;
  background: rgba(255,255,255,0.86);
  color: var(--ink);
  box-shadow: 0 4px 12px rgba(45,43,78,0.08);
}

.filter-btn:hover {
  transform: translateY(-1px) scale(1.03);
  box-shadow: 0 4px 10px rgba(45,43,78,0.12);
}

.filter-btn:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 2px;
}

.filter-btn.active {
  background: linear-gradient(180deg, #65C3F2 0%, var(--blue) 100%);
  color: white;
  border-color: rgba(43,142,196,0.35);
  box-shadow: 0 5px 12px rgba(78,174,229,0.28);
  transform: translateY(-1px);
}

/* ── Letter Heading ─────────────────────────────────────────── */
.letter-heading {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.letter-badge {
  font-family: var(--font-display);
  font-size: 2.25rem;
  width: 58px;
  height: 58px;
  background: linear-gradient(135deg, var(--yellow) 0%, var(--coral) 100%);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  box-shadow: 0 5px 12px rgba(255,217,74,0.24);
  border-bottom: 2px solid rgba(240,184,0,0.58);
  flex-shrink: 0;
  transition: var(--transition);
}

#letter-title {
  font-family: var(--font-display);
  font-size: 1.55rem;
  color: var(--ink);
}

.letter-count {
  font-size: 0.9rem;
  color: var(--ink-light);
  font-weight: 600;
  margin-top: 2px;
}

/* ── Cards Grid ─────────────────────────────────────────────── */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 28px;
  perspective: 1000px;
}

/* ── Explorer Card ──────────────────────────────────────────── */
.explorer-card {
  background: linear-gradient(180deg, #ffffff 0%, #FBFDFF 100%);
  border-radius: var(--radius-md);
  padding: 0;
  box-shadow: 0 9px 22px rgba(45,43,78,0.1);
  border: 1px solid rgba(78,174,229,0.08);
  cursor: pointer;
  transition: transform 0.18s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.18s ease, border-color 0.18s ease, filter 0.18s ease;
  position: relative;
  overflow: hidden;
  display: flex;
  animation: cardIn 0.4s cubic-bezier(0.34,1.4,0.64,1) both;
}

.explorer-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 0;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
}

.explorer-card::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(105deg, transparent 40%, rgba(255,255,255,0.45) 50%, transparent 60%);
  transform: translateX(-100%);
  transition: transform 0.6s ease;
  pointer-events: none;
}

.explorer-card:hover::after {
  transform: translateX(100%);
}

.explorer-card[data-category="Country"]::before  { background: linear-gradient(90deg, var(--blue), var(--mint)); }
.explorer-card[data-category="Landmark"]::before { background: linear-gradient(90deg, var(--yellow), var(--coral)); }
.explorer-card[data-category="Nature"]::before   { background: linear-gradient(90deg, var(--mint), #A8E6CF); }
.explorer-card[data-category="Capital"]::before  { background: linear-gradient(90deg, var(--lavender), var(--blue)); }
.explorer-card[data-category="City"]::before     { background: linear-gradient(90deg, var(--coral), var(--lavender)); }

@keyframes cardIn {
  0%   { opacity: 0; transform: translateY(20px) scale(0.92); }
  100% { opacity: 1; transform: translateY(0) scale(1); }
}

.explorer-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 28px rgba(45,43,78,0.13);
  border-color: rgba(78,174,229,0.16);
  filter: saturate(1.05);
}

.explorer-card.selected {
  border-color: rgba(43,142,196,0.45);
  box-shadow: 0 12px 26px rgba(78,174,229,0.17), 0 0 0 2px rgba(78,174,229,0.1);
}

.explorer-card.selected::after {
  transform: translateX(100%);
}


.explorer-card:active {
  transform: translateY(-1px) scale(0.99);
}

.explorer-card:hover .card-emoji {
  animation: wiggle 0.5s ease-in-out;
}

@keyframes wiggle {
  0%,100% { transform: rotate(0deg); }
  25%      { transform: rotate(-8deg) scale(1.1); }
  75%      { transform: rotate(8deg) scale(1.1); }
}

.explorer-card:focus-visible {
  outline: 3px solid var(--blue-deep);
  outline-offset: 3px;
}

.card-inner {
  padding: 24px 24px 20px;
  display: flex;
  flex: 1;
  flex-direction: column;
  min-width: 0;
}

.card-xp {
  position: absolute;
  top: 18px;
  right: 22px;
  font-size: 0.68rem;
  font-weight: 900;
  padding: 5px 11px;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, #FFD94A 0%, #FFB347 100%);
  color: #6B4200;
  box-shadow: 0 2px 6px rgba(255,183,38,0.34);
  letter-spacing: 0.3px;
  z-index: 2;
  animation: xpPulse 2.5s ease-in-out infinite;
}

@keyframes xpPulse {
  0%,100% { transform: scale(1); }
  50%     { transform: scale(1.06); }
}

.card-series {
  width: fit-content;
  margin: 0 0 12px;
  padding: 5px 12px;
  border-radius: var(--radius-xl);
  background: rgba(109,213,176,0.14);
  color: var(--blue-deep);
  font-size: 0.64rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.7px;
}

.card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 10px;
  padding-top: 2px;
}

.card-emoji {
  font-size: 2.8rem;
  filter: drop-shadow(0 3px 6px rgba(0,0,0,0.1));
  display: inline-block;
  line-height: 1;
  transform-origin: 50% 80%;
}

.card-category-badge {
  font-size: 0.7rem;
  font-weight: 800;
  padding: 4px 10px;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  margin-top: 4px;
}

.badge-Country  { background: #D4EEFF; color: #07436E; }
.badge-Landmark { background: #FFF3C4; color: #6B4900; }
.badge-Nature   { background: #D1F5E5; color: #0A5C3C; }
.badge-Capital  { background: #EAE3FF; color: #3B2060; }
.badge-City     { background: #FFE0D4; color: #7A2800; }

.card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--ink);
  margin-bottom: 4px;
  line-height: 1.2;
}

.card-region {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--ink-light);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 4px;
}

.card-region::before {
  content: '📍';
  font-size: 0.8rem;
}

.card-fact {
  font-size: 0.84rem;
  color: var(--ink-light);
  line-height: 1.5;
  margin-bottom: 18px;
  font-weight: 600;
}

.card-explore-btn {
  font-family: var(--font-body);
  font-weight: 900;
  font-size: 0.82rem;
  padding: 11px 20px;
  border-radius: 14px;
  border: none;
  background: linear-gradient(180deg, #56BDF0 0%, #2FA7DF 100%);
  color: white;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, filter 0.15s ease;
  box-shadow: 0 4px 9px rgba(78,174,229,0.26);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  width: 100%;
  margin-top: auto;
}

.card-explore-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 13px rgba(78,174,229,0.32);
  filter: brightness(1.04) saturate(1.08);
}

.card-explore-btn:active {
  transform: translateY(1px) scale(0.98);
  box-shadow: 0 2px 6px rgba(78,174,229,0.24);
}

/* Animation stagger for cards */
.explorer-card:nth-child(1) { animation-delay: 0.04s; }
.explorer-card:nth-child(2) { animation-delay: 0.08s; }
.explorer-card:nth-child(3) { animation-delay: 0.12s; }
.explorer-card:nth-child(4) { animation-delay: 0.16s; }
.explorer-card:nth-child(5) { animation-delay: 0.20s; }
.explorer-card:nth-child(6) { animation-delay: 0.24s; }

/* ── Empty State ─────────────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 60px 24px;
  animation: cardIn 0.4s ease both;
}

.empty-scene {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  background: rgba(255,255,255,0.7);
  border-radius: var(--radius-lg);
  padding: 48px 60px;
  box-shadow: 0 4px 24px var(--shadow);
  border: 2px dashed rgba(78,174,229,0.3);
}

.empty-globe {
  font-size: 4rem;
  animation: globeFloat 3s ease-in-out infinite;
  filter: grayscale(0.3);
}

.empty-title {
  font-family: var(--font-display);
  font-size: 1.4rem;
  color: var(--ink);
}

.empty-sub {
  font-size: 0.95rem;
  color: var(--ink-light);
  font-weight: 600;
  line-height: 1.5;
}

.empty-compass {
  font-size: 2rem;
  animation: pinBounce 2s ease-in-out infinite;
}

/* ── DETAIL PANEL ───────────────────────────────────────────── */
.modal-overlay {
  position: sticky;
  top: 152px;
  z-index: 20;
  display: block;
  align-self: start;
  height: calc(100vh - 170px);
}

.modal-overlay[hidden] { display: none !important; }

.modal-panel {
  background: rgba(255,255,255,0.96);
  width: 100%;
  height: 100%;
  overflow-y: auto;
  padding: 32px 28px 48px;
  position: relative;
  border-radius: 18px;
  box-shadow: 0 12px 28px rgba(45,43,78,0.12);
  border: 3px solid rgba(78,174,229,0.58);

  /* Subtle notebook paper texture */
  background-image: repeating-linear-gradient(
    transparent,
    transparent 27px,
    rgba(78,174,229,0.06) 27px,
    rgba(78,174,229,0.06) 28px
  );
}

.modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 2px solid rgba(45,43,78,0.15);
  background: rgba(255,255,255,0.9);
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 900;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  outline: none;
}

.modal-close:hover {
  background: var(--coral);
  color: white;
  border-color: var(--coral-dk);
  transform: scale(1.1) rotate(90deg);
}

.modal-close:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 2px;
}

.modal-badge-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  margin-top: 8px;
}

.modal-emoji {
  font-size: 3.5rem;
  filter: drop-shadow(0 4px 12px rgba(0,0,0,0.12));
  animation: modalEmojiPop 0.4s cubic-bezier(0.34,1.56,0.64,1) 0.1s both;
}

@keyframes modalEmojiPop {
  0%   { transform: scale(0.5) rotate(-20deg); opacity: 0; }
  100% { transform: scale(1) rotate(0deg); opacity: 1; }
}

.modal-category-pill {
  font-size: 0.75rem;
  font-weight: 800;
  padding: 5px 14px;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
}

.modal-title {
  font-family: var(--font-display);
  font-size: 2rem;
  color: var(--ink);
  margin-bottom: 8px;
  line-height: 1.15;
}

.modal-location {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--ink-light);
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 4px;
}

.modal-capital {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--blue-deep);
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 20px;
}

.modal-facts {
  background: linear-gradient(135deg, #F0F9FF, #FAFFF8);
  border-radius: var(--radius-md);
  padding: 18px;
  margin-bottom: 20px;
  border: 1.5px solid rgba(78,174,229,0.2);
}

.modal-fact-item {
  display: flex;
  gap: 10px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--ink);
  line-height: 1.5;
  padding: 6px 0;
  border-bottom: 1px dashed rgba(78,174,229,0.2);
}

.modal-fact-item:last-child { border-bottom: none; }

.fact-bullet {
  font-size: 0.9rem;
  flex-shrink: 0;
  margin-top: 1px;
}

.modal-map-prompt {
  background: linear-gradient(135deg, var(--yellow) 0%, #FFE87A 100%);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
  border: 2px solid var(--yellow-dk);
  cursor: pointer;
  transition: transform 0.16s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.16s ease, filter 0.16s ease;
  width: 100%;
  text-align: left;
}

.modal-map-prompt:hover {
  transform: translateY(-3px);
  box-shadow: 0 7px 18px rgba(255,217,74,0.4);
  filter: brightness(1.03);
}

.modal-map-prompt:active {
  transform: translateY(1px) scale(0.99);
}

.modal-map-prompt:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
}

.map-icon { font-size: 1.5rem; }

.modal-map-prompt span:last-child {
  font-family: var(--font-display);
  font-size: 1.05rem;
  color: #5A4200;
}

.modal-related {
  margin-bottom: 24px;
}

.modal-related-label {
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--ink-light);
  margin-bottom: 8px;
}

.related-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.related-tag {
  font-size: 0.8rem;
  font-weight: 700;
  padding: 5px 12px;
  background: rgba(195,177,225,0.25);
  color: var(--lav-dk);
  border-radius: 999px;
  border: 1.5px solid rgba(155,127,209,0.3);
}

.explorer-badge {
  background: linear-gradient(135deg, #FFD94A 0%, #FF9BB5 60%, #C3B1E1 100%);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: 0 4px 18px rgba(255,154,40,0.3);
  border: 2px solid rgba(255,255,255,0.5);
}

.badge-star { font-size: 1.5rem; animation: twinkle 1.5s ease-in-out infinite; }
.badge-star:last-child { animation-delay: 0.75s; }

@keyframes twinkle {
  0%,100% { transform: scale(1); opacity: 1; }
  50%      { transform: scale(1.18); opacity: 0.78; }
}

.badge-title {
  font-family: var(--font-display);
  font-size: 1rem;
  color: white;
  text-shadow: 0 1px 4px rgba(0,0,0,0.2);
}

.badge-sub {
  font-size: 0.8rem;
  font-weight: 700;
  color: rgba(255,255,255,0.85);
}


/* ── MAP CHALLENGE ──────────────────────────────────────────── */
.challenge-overlay {
  position: fixed;
  inset: 0;
  z-index: 300;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(45,43,78,0.62);
  backdrop-filter: blur(8px);
  animation: overlayIn 0.22s ease both;
}

.challenge-overlay[hidden] { display: none !important; }

.challenge-panel {
  position: relative;
  width: min(980px, 96vw);
  max-height: min(94vh, 860px);
  overflow-y: auto;
  border-radius: 28px;
  padding: 26px;
  background:
    radial-gradient(circle at 90% 12%, rgba(255,217,74,0.28) 0%, transparent 24%),
    linear-gradient(160deg, #ffffff 0%, #F4FBFF 58%, #FFF8E7 100%);
  border: 3px solid rgba(255,255,255,0.9);
  box-shadow: 0 14px 0 rgba(78,174,229,0.22), 0 28px 70px rgba(45,43,78,0.34);
  animation: challengePop 0.34s cubic-bezier(0.34,1.56,0.64,1) both;
}

@keyframes challengePop {
  0% { transform: scale(0.88) translateY(18px); opacity: 0; }
  100% { transform: scale(1) translateY(0); opacity: 1; }
}

.challenge-close {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 38px;
  height: 38px;
  border: none;
  border-radius: 50%;
  background: white;
  color: var(--ink);
  font-weight: 900;
  cursor: pointer;
  box-shadow: 0 3px 0 rgba(45,43,78,0.12), 0 6px 14px var(--shadow);
  transition: transform 0.16s cubic-bezier(0.34,1.56,0.64,1), background 0.16s ease;
}

.challenge-close:hover {
  background: var(--coral);
  color: white;
  transform: rotate(90deg) scale(1.08);
}

.challenge-head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding-right: 42px;
  margin-bottom: 16px;
}

.challenge-badge {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border-radius: 18px;
  background: linear-gradient(180deg, #FFF5B8 0%, var(--yellow) 100%);
  box-shadow: 0 5px 0 var(--yellow-dk), 0 10px 20px rgba(255,217,74,0.34);
  font-size: 1.9rem;
  flex-shrink: 0;
}

.challenge-title {
  font-family: var(--font-display);
  font-size: clamp(1.65rem, 4vw, 2.5rem);
  color: var(--ink);
  line-height: 1.1;
}

.challenge-subtitle {
  margin-top: 4px;
  color: var(--ink-light);
  font-weight: 800;
}

.challenge-map-wrap {
  border-radius: 22px;
  padding: 4px;
  background: rgba(78,174,229,0.1);
  border: 2px solid rgba(78,174,229,0.14);
}

.challenge-map {
  position: relative;
  overflow: hidden;
  aspect-ratio: 3 / 2;
  border-radius: 18px;
  cursor: crosshair;
  background: #BFE9FF;
  box-shadow: none;
}

.challenge-map:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 4px;
}

.world-map-art {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
  border-radius: inherit;
  user-select: none;
  pointer-events: none;
}

.explorer-pin,
.target-glow,
.success-burst {
  position: absolute;
  left: var(--pin-x, 50%);
  top: var(--pin-y, 50%);
  transform: translate(-50%, -100%);
  pointer-events: none;
}

.explorer-pin {
  font-size: clamp(1.9rem, 5vw, 2.8rem);
  filter: drop-shadow(0 8px 8px rgba(45,43,78,0.28));
  animation: pinDrop 0.42s cubic-bezier(0.34,1.56,0.64,1) both;
  z-index: 5;
}

@keyframes pinDrop {
  0% { transform: translate(-50%, -180%) scale(0.75); opacity: 0; }
  65% { transform: translate(-50%, -92%) scale(1.12); opacity: 1; }
  100% { transform: translate(-50%, -100%) scale(1); opacity: 1; }
}

.target-glow {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(255,217,74,0.58) 0%, rgba(255,217,74,0.28) 36%, transparent 70%);
  border: 3px dashed rgba(255,127,92,0.5);
  animation: targetPulse 1.3s ease-in-out infinite;
  z-index: 3;
}

@keyframes targetPulse {
  0%,100% { transform: translate(-50%, -50%) scale(0.88); opacity: 0.75; }
  50% { transform: translate(-50%, -50%) scale(1.08); opacity: 1; }
}

.success-burst {
  transform: translate(-50%, -50%);
  z-index: 6;
}

.success-burst span {
  position: absolute;
  color: var(--yellow-dk);
  font-size: 1.2rem;
  animation: sparklePop 0.8s ease-out both;
}
.success-burst span:nth-child(1) { transform: translate(-38px, -30px); }
.success-burst span:nth-child(2) { transform: translate(26px, -34px); animation-delay: 0.05s; }
.success-burst span:nth-child(3) { transform: translate(-44px, 20px); animation-delay: 0.1s; }
.success-burst span:nth-child(4) { transform: translate(34px, 18px); animation-delay: 0.15s; }
.success-burst span:nth-child(5) { transform: translate(0, -52px); animation-delay: 0.2s; }

@keyframes sparklePop {
  0% { opacity: 0; scale: 0.4; }
  45% { opacity: 1; scale: 1.35; }
  100% { opacity: 0; scale: 0.8; }
}

.challenge-feedback {
  min-height: 44px;
  margin: 16px 0 14px;
  padding: 12px 16px;
  border-radius: 16px;
  background: rgba(255,255,255,0.78);
  border: 2px solid rgba(78,174,229,0.14);
  color: var(--ink);
  font-weight: 800;
  line-height: 1.35;
}

.challenge-feedback.success {
  background: linear-gradient(135deg, #E6FFF4 0%, #FFF9D9 100%);
  border-color: rgba(88,213,176,0.5);
  color: #0A5C3C;
}

.challenge-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}

.challenge-btn {
  font-family: var(--font-body);
  font-weight: 900;
  font-size: 0.86rem;
  padding: 10px 16px;
  border-radius: var(--radius-xl);
  border: 2px solid rgba(45,43,78,0.1);
  background: white;
  color: var(--ink);
  cursor: pointer;
  box-shadow: 0 3px 0 rgba(45,43,78,0.1), 0 8px 16px var(--shadow);
  transition: transform 0.15s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.15s ease;
}

.challenge-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 5px 0 rgba(45,43,78,0.1), 0 12px 22px var(--shadow-md);
}

.challenge-btn:active {
  transform: translateY(1px) scale(0.98);
  box-shadow: 0 1px 0 rgba(45,43,78,0.1);
}

.challenge-btn-primary {
  background: linear-gradient(180deg, #6BC4F0 0%, var(--blue) 100%);
  color: white;
  border-color: var(--blue-deep);
  box-shadow: 0 4px 0 var(--blue-deep), 0 8px 18px rgba(78,174,229,0.34);
}

/* ── FOOTER ─────────────────────────────────────────────────── */
.site-footer {
  text-align: center;
  padding: 24px;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--ink-light);
  border-top: 2px solid rgba(78,174,229,0.15);
  background: rgba(255,255,255,0.5);
}

/* ── RESPONSIVE ─────────────────────────────────────────────── */
@media (min-width: 861px) and (max-width: 1080px) {
  .header-inner { width: calc(100% - 36px); gap: 14px; }
  .brand-subtitle { display: none; }
  .reward-bar { gap: 8px; }
  .reward-chip { padding: 5px 8px; font-size: 0.72rem; }
  .passport-profile { gap: 10px; }
  .passport-open { height: 48px; padding-inline: 15px; font-size: 0.94rem; }
  .explorer-avatar { width: 44px; height: 44px; }
}

@media (max-width: 640px) {
  .site-header    { position: sticky; }
  .header-inner   {
    display: grid;
    grid-template-columns: 1fr auto;
    width: calc(100% - 28px);
    min-height: 0;
    padding: 9px 0 10px;
    gap: 8px 10px;
  }
  .brand          { min-width: 0; gap: 9px; }
  .brand-icon     { width: 42px; height: 42px; }
  .brand-title    { font-size: 1.46rem; }
  .brand-subtitle { display: none; }
  .reward-bar     {
    grid-column: 1 / -1;
    margin-left: 0;
  }
  .reward-stats   {
    flex-wrap: nowrap;
    justify-content: flex-start;
    gap: 6px;
    overflow-x: auto;
    scrollbar-width: none;
  }
  .reward-stats::-webkit-scrollbar { display: none; }
  .reward-chip    { flex-shrink: 0; min-height: 28px; padding: 4px 8px; font-size: 0.72rem; }
  .passport-profile { align-self: center; gap: 8px; }
  .passport-open  { height: 42px; padding: 0 12px; font-size: 0.86rem; }
  .passport-icon  { width: 22px; height: 22px; }
  .explorer-avatar { width: 40px; height: 40px; }
  .alphabet-section {
    top: 128px;
    padding: 8px 14px 10px;
  }
  .alphabet-helper { display: none; }
  .passport-overlay { padding: 12px; }
  .passport-panel { padding: 22px 16px; border-radius: 22px; }
  .passport-mark { width: 48px; height: 48px; padding: 7px; }
  .hero-section   { width: calc(100% - 28px); margin: 10px auto; border-radius: 18px; box-shadow: 0 4px 12px rgba(45,43,78,0.07); }
  .alpha-strip    { gap: 9px; }
  .alpha-btn      { width: 38px; height: 38px; border-radius: 14px; font-size: 0.96rem; }
  .alpha-btn.active { transform: translateY(-2px) scale(1.16); }
  .main-content   { padding: 0 14px 48px; }
  .letter-badge   { width: 52px; height: 52px; font-size: 2rem; }
  #letter-title   { font-size: 1.28rem; }
  .cards-grid     { grid-template-columns: repeat(auto-fill, minmax(168px, 1fr)); gap: 14px; }
  .card-inner     { padding: 22px 16px 16px; }
  .card-xp        { top: 16px; right: 14px; }
  .card-emoji     { font-size: 2rem; }
  .card-title     { font-size: 1.05rem; }
  .filter-section { gap: 8px; padding: 12px; }
  body.detail-panel-open .page-layout { display: block; padding-right: 0; }
  .modal-overlay  { position: fixed; inset: auto 0 0; top: auto; z-index: 210; height: min(82vh, 680px); padding: 0 12px 12px; }
  .modal-panel    { width: 100%; padding: 24px 18px 40px; border-radius: 24px 24px 18px 18px; box-shadow: 0 -12px 34px rgba(45,43,78,0.18); }
  .modal-title    { font-size: 1.5rem; }
  .modal-emoji    { font-size: 2.8rem; }
  .challenge-overlay { padding: 12px; }
  .challenge-panel   { padding: 20px 16px; border-radius: 22px; }
  .challenge-head    { align-items: flex-start; gap: 10px; }
  .challenge-badge   { width: 46px; height: 46px; font-size: 1.5rem; border-radius: 14px; }
  .challenge-actions { justify-content: stretch; }
  .challenge-btn     { flex: 1 1 calc(50% - 8px); }
}

@media (min-width: 641px) and (max-width: 860px) {
  .header-inner   {
    width: calc(100% - 36px);
    flex-wrap: wrap;
    min-height: 0;
    padding: 10px 0;
  }
  .brand          { min-width: 0; }
  .brand-title    { font-size: 1.98rem; }
  .brand-subtitle { font-size: 0.88rem; }
  .reward-bar     {
    order: 3;
    flex: 1 1 100%;
    margin-left: 0;
  }
  .reward-stats   { justify-content: flex-start; }
  .alphabet-section { top: 126px; }
  .alphabet-helper { display: none; }
  .hero-section   { width: calc(100% - 36px); margin-top: 14px; border-radius: 20px; }
  body.detail-panel-open .page-layout { display: block; padding-right: 0; }
  .modal-overlay  { position: fixed; inset: auto 0 0; top: auto; z-index: 210; height: min(78vh, 720px); padding: 0 18px 18px; }
  .modal-panel    { border-radius: 28px 28px 20px 20px; box-shadow: 0 -12px 34px rgba(45,43,78,0.18); }
  .cards-grid { grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); }
}

/* ── Reduced Motion ─────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}