/* ===== 数学小岛 · 全局样式 ===== */
:root {
  --coral: #FF7E6B;
  --coral-deep: #E85A47;
  --sun: #FFC23C;
  --sun-deep: #E69A15;
  --mint: #6FD3A8;
  --mint-deep: #3FA77B;
  --lavender: #B49CE0;
  --lavender-deep: #8B6BC9;
  --sky: #6FBDF0;
  --sky-deep: #3B8FCE;
  --berry: #F47CA8;
  --berry-deep: #D14A82;

  --ink: #3D2E50;
  --ink-soft: #6E5E80;
  --paper: #FFFBF2;
  --cream: #FFF3DC;
  --card: #FFFFFF;

  --shadow-sm: 0 2px 0 rgba(61,46,80,.12);
  --shadow-md: 0 4px 0 rgba(61,46,80,.16), 0 8px 24px rgba(61,46,80,.08);
  --shadow-lg: 0 6px 0 rgba(61,46,80,.18), 0 18px 40px rgba(61,46,80,.14);

  --r-sm: 12px;
  --r-md: 18px;
  --r-lg: 28px;
  --r-xl: 40px;

  --font-cn: "ZCOOL KuaiLe", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Nunito", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-num: "Fredoka", "Baloo 2", "Nunito", sans-serif;
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
  font-family: var(--font-body);
  color: var(--ink);
  background: #FFE8C9;
  -webkit-font-smoothing: antialiased;
  user-select: none;
}
button { font-family: inherit; color: inherit; }

#root {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ============ 顶部状态条 ============ */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 22px;
  background: linear-gradient(180deg, rgba(255,251,242,.95), rgba(255,251,242,.78));
  backdrop-filter: blur(8px);
}
.topbar .brand {
  font-family: var(--font-cn);
  font-size: 26px;
  letter-spacing: 2px;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 10px;
}
.topbar .brand-mark {
  width: 38px; height: 38px;
  border-radius: 12px;
  background: var(--coral);
  display: grid; place-items: center;
  color: #fff;
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 22px;
  box-shadow: var(--shadow-sm);
  transform: rotate(-6deg);
}
.topbar .spacer { flex: 1; }
.topbar .stat {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px 8px 12px;
  background: #fff;
  border-radius: 999px;
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 20px;
  color: var(--ink);
  box-shadow: var(--shadow-sm);
}
.topbar .stat svg { width: 24px; height: 24px; }

.topbar .back {
  border: none;
  background: #fff;
  border-radius: 999px;
  padding: 8px 16px 8px 12px;
  font-family: var(--font-cn);
  font-size: 18px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  box-shadow: var(--shadow-sm);
  transition: transform .15s;
}
.topbar .back:hover { transform: translateY(-2px); }
.topbar .back:active { transform: translateY(1px); box-shadow: none; }

/* ============ 通用按钮 ============ */
.btn {
  border: none;
  cursor: pointer;
  font-family: var(--font-cn);
  font-size: 22px;
  letter-spacing: 1px;
  padding: 14px 28px;
  border-radius: var(--r-lg);
  background: var(--coral);
  color: #fff;
  box-shadow: 0 4px 0 var(--coral-deep), 0 10px 22px rgba(255,126,107,.35);
  transition: transform .12s, box-shadow .12s;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(2px); box-shadow: 0 0 0 var(--coral-deep); }
.btn.btn-sun { background: var(--sun); box-shadow: 0 4px 0 var(--sun-deep), 0 10px 22px rgba(255,194,60,.35); }
.btn.btn-sun:active { box-shadow: 0 0 0 var(--sun-deep); }
.btn.btn-mint { background: var(--mint); box-shadow: 0 4px 0 var(--mint-deep), 0 10px 22px rgba(111,211,168,.4); }
.btn.btn-mint:active { box-shadow: 0 0 0 var(--mint-deep); }
.btn.btn-sky { background: var(--sky); box-shadow: 0 4px 0 var(--sky-deep), 0 10px 22px rgba(111,189,240,.4); }
.btn.btn-sky:active { box-shadow: 0 0 0 var(--sky-deep); }
.btn.btn-lavender { background: var(--lavender); box-shadow: 0 4px 0 var(--lavender-deep), 0 10px 22px rgba(180,156,224,.4); }
.btn.btn-lavender:active { box-shadow: 0 0 0 var(--lavender-deep); }
.btn.ghost {
  background: #fff;
  color: var(--ink);
  box-shadow: 0 3px 0 rgba(61,46,80,.18);
}
.btn.ghost:active { box-shadow: 0 0 0 rgba(61,46,80,.18); }
.btn.sm { padding: 10px 18px; font-size: 18px; border-radius: 20px; }

/* ============ 主地图 ============ */
.map-screen {
  flex: 1;
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse 60% 50% at 20% 12%, #FFE0AC 0%, transparent 60%),
    radial-gradient(ellipse 50% 50% at 85% 8%, #FFD6E2 0%, transparent 55%),
    radial-gradient(ellipse 70% 60% at 50% 105%, #C8EFE4 0%, transparent 60%),
    linear-gradient(180deg, #FFE8C9 0%, #FFD7C2 40%, #C8EFE4 100%);
}
.map-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 30px 40px 80px;
  position: relative;
}
.map-title {
  text-align: center;
  font-family: var(--font-cn);
  font-size: 44px;
  letter-spacing: 4px;
  color: var(--ink);
  margin: 10px 0 4px;
  text-shadow: 0 3px 0 #fff;
}
.map-sub {
  text-align: center;
  font-size: 18px;
  color: var(--ink-soft);
  margin: 0 0 30px;
  letter-spacing: 1px;
}
.map-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  grid-auto-rows: 14px;
  gap: 0;
  position: relative;
}
.island {
  position: relative;
  background: var(--card);
  border-radius: 36px;
  padding: 22px 22px 24px;
  box-shadow: var(--shadow-lg);
  cursor: pointer;
  transition: transform .2s, box-shadow .2s;
  display: flex;
  flex-direction: column;
  gap: 14px;
  overflow: hidden;
}
.island:hover { transform: translateY(-4px) rotate(-.5deg); }
.island:active { transform: translateY(0); }
.island .island-bg {
  position: absolute;
  inset: 0;
  opacity: .35;
  pointer-events: none;
  z-index: 0;
}
.island > * { position: relative; z-index: 1; }
.island .island-num {
  position: absolute;
  top: 16px;
  right: 18px;
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 60px;
  line-height: 1;
  color: rgba(255,255,255,.85);
  z-index: 0;
  -webkit-text-stroke: 2px rgba(61,46,80,.12);
}
.island .island-mascot {
  width: 110px; height: 110px;
  align-self: flex-start;
}
.island h3 {
  font-family: var(--font-cn);
  font-size: 28px;
  margin: 0;
  letter-spacing: 2px;
}
.island p {
  margin: 0;
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.55;
}
.island .island-foot {
  margin-top: auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.island .stage-pips {
  display: flex;
  gap: 6px;
}
.island .pip {
  width: 14px; height: 14px;
  border-radius: 50%;
  background: rgba(61,46,80,.12);
}
.island .pip.done { background: var(--sun); box-shadow: 0 0 0 3px rgba(255,194,60,.25); }
.island .go {
  font-family: var(--font-cn);
  font-size: 18px;
  background: var(--ink);
  color: #fff;
  border-radius: 999px;
  padding: 8px 16px;
  letter-spacing: 1px;
}

/* islands variants */
.island.c1 { background: linear-gradient(165deg, #FFEFC9 0%, #FFE0A0 100%); }
.island.c1 .go { background: var(--sun-deep); }
.island.c2 { background: linear-gradient(165deg, #FFE3D1 0%, #FFC2A8 100%); }
.island.c2 .go { background: var(--coral-deep); }
.island.c3 { background: linear-gradient(165deg, #FFDDEC 0%, #FFB7D2 100%); }
.island.c3 .go { background: var(--berry-deep); }
.island.c4 { background: linear-gradient(165deg, #E2F4FF 0%, #BBE0FF 100%); }
.island.c4 .go { background: var(--sky-deep); }
.island.c5 { background: linear-gradient(165deg, #DEF8E8 0%, #B7EBCE 100%); }
.island.c5 .go { background: var(--mint-deep); }

/* clouds + decorations */
.cloud {
  position: absolute;
  pointer-events: none;
  opacity: .8;
}

/* ============ 章节通用页面 ============ */
.chapter-screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}
.chapter-bg-c1 { background: linear-gradient(180deg, #FFF6DC 0%, #FFE9B0 100%); }
.chapter-bg-c2 { background: linear-gradient(180deg, #FFEFE3 0%, #FFD2B5 100%); }
.chapter-bg-c3 { background: linear-gradient(180deg, #FFE9F2 0%, #FFC4DC 100%); }
.chapter-bg-c4 { background: linear-gradient(180deg, #E9F4FF 0%, #C2DDFA 100%); }
.chapter-bg-c5 { background: linear-gradient(180deg, #E7F8EC 0%, #BBE9C9 100%); }

.chapter-body {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 30px 60px;
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
}

.stage-tabs {
  display: flex;
  gap: 10px;
  background: rgba(255,255,255,.6);
  padding: 6px;
  border-radius: 999px;
  margin-bottom: 22px;
  box-shadow: var(--shadow-sm);
}
.stage-tab {
  border: none;
  background: transparent;
  font-family: var(--font-cn);
  font-size: 17px;
  letter-spacing: 1px;
  padding: 10px 22px;
  border-radius: 999px;
  cursor: pointer;
  color: var(--ink-soft);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.stage-tab.active {
  background: #fff;
  color: var(--ink);
  box-shadow: var(--shadow-sm);
}
.stage-tab .star-mini {
  width: 16px; height: 16px;
  display: inline-block;
}

/* card containing a mini-game */
.game-card {
  background: var(--card);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-lg);
  padding: 32px 36px;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 22px;
}
.game-prompt {
  display: flex;
  align-items: flex-start;
  gap: 18px;
}
.game-prompt .bubble {
  flex: 1;
  background: var(--cream);
  border-radius: 22px;
  padding: 14px 20px;
  font-family: var(--font-cn);
  font-size: 22px;
  letter-spacing: 1px;
  position: relative;
  line-height: 1.5;
}
.game-prompt .bubble::before {
  content: '';
  position: absolute;
  left: -12px;
  top: 22px;
  width: 0; height: 0;
  border: 10px solid transparent;
  border-right-color: var(--cream);
}
.game-prompt .mascot-sm {
  width: 84px; height: 84px;
  flex-shrink: 0;
}

.option-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
}
.opt {
  min-width: 110px;
  padding: 16px 24px;
  background: #fff;
  border: 3px solid #F0E6D5;
  border-radius: var(--r-md);
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 28px;
  color: var(--ink);
  cursor: pointer;
  box-shadow: 0 4px 0 #E8DDCB;
  transition: transform .12s;
}
.opt:hover { transform: translateY(-2px); }
.opt.correct {
  background: var(--mint);
  color: #fff;
  border-color: var(--mint-deep);
  box-shadow: 0 4px 0 var(--mint-deep);
  animation: bounce .4s;
}
.opt.wrong {
  background: #FFD0CC;
  border-color: var(--coral);
  color: var(--coral-deep);
  animation: shake .35s;
}
.opt.disabled { opacity: .5; pointer-events: none; }

@keyframes bounce {
  0%   { transform: scale(1); }
  35%  { transform: scale(1.18); }
  60%  { transform: scale(.95); }
  100% { transform: scale(1); }
}
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-8px); }
  40% { transform: translateX(8px); }
  60% { transform: translateX(-6px); }
  80% { transform: translateX(6px); }
}
@keyframes pop-in {
  0% { transform: scale(.3) rotate(-20deg); opacity: 0; }
  60% { transform: scale(1.1) rotate(4deg); opacity: 1; }
  100% { transform: scale(1) rotate(0); }
}
@keyframes float-up {
  0% { transform: translateY(0); opacity: 1; }
  100% { transform: translateY(-80px); opacity: 0; }
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(230,154,21,.5); }
  50% { box-shadow: 0 0 0 6px rgba(230,154,21,0); }
}

/* ============ 反馈弹窗 ============ */
.feedback {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  z-index: 100;
  background: rgba(61,46,80,.4);
  animation: pop-in .25s;
}
.feedback .card {
  background: #fff;
  border-radius: 36px;
  padding: 40px 48px;
  text-align: center;
  box-shadow: var(--shadow-lg);
  min-width: 360px;
  animation: pop-in .4s;
}
.feedback h2 {
  font-family: var(--font-cn);
  font-size: 36px;
  margin: 14px 0 6px;
  letter-spacing: 2px;
}
.feedback .stars-big {
  display: flex; justify-content: center; gap: 8px;
  margin: 6px 0 18px;
}
.feedback .stars-big svg { width: 56px; height: 56px; }
.feedback p {
  font-size: 18px;
  color: var(--ink-soft);
  margin: 0 0 22px;
}

/* floating reward animation */
.floater {
  position: absolute;
  font-family: var(--font-num);
  font-weight: 800;
  font-size: 32px;
  color: var(--sun-deep);
  pointer-events: none;
  animation: float-up 1s forwards;
}

/* progress bar within a chapter */
.chap-header {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  margin: 4px 0 18px;
}
.chap-title {
  font-family: var(--font-cn);
  font-size: 30px;
  letter-spacing: 2px;
  margin: 0;
}
.progress {
  flex: 1;
  height: 14px;
  background: rgba(255,255,255,.7);
  border-radius: 999px;
  overflow: hidden;
  box-shadow: inset 0 2px 0 rgba(61,46,80,.06);
}
.progress > i {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--sun) 0%, var(--coral) 100%);
  border-radius: 999px;
  transition: width .4s ease;
}

/* ====== utility ====== */
.center { text-align: center; }
.muted { color: var(--ink-soft); }
.num { font-family: var(--font-num); font-weight: 700; }
.hidden { display: none !important; }