/* 四年级英语动画城 —— 共享样式（海绵宝宝 × 汪汪队 × 艾莎 × 米奇 主题） */
:root {
  --sb-yellow: #ffd937;      /* 海绵宝宝黄 */
  --sb-dark: #d9a800;
  --paw-blue: #1e88e5;       /* 汪汪队蓝 */
  --paw-dark: #0d5ca8;
  --ice-blue: #8fd8f0;       /* 艾莎冰蓝 */
  --ice-dark: #3aa5c9;
  --mk-red: #e53935;         /* 米奇红 */
  --mk-dark: #a92622;
  --pp-pink: #f48fb1;        /* 佩奇粉 */
  --candy: #ff8a3d;
  --ink: #2b2b2b;
  --paper: #fffdf5;
  --sky: #d8f1ff;
  --ok: #2e9e44;
  --bad: #d9483b;
  --gold: #fcd535;
  --shadow: 0 4px 0 rgba(0,0,0,.18);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: linear-gradient(180deg, var(--sky) 0%, #fdf6e3 45%, var(--paper) 100%);
  background-attachment: fixed;
  line-height: 1.75;
  font-size: 17px;
}

.wrap { max-width: 900px; margin: 0 auto; padding: 16px 20px 80px; }

/* 英文统一字体感 */
.en, .q .q-text b, .word-chip b {
  font-family: "Comic Sans MS", "Chalkboard SE", "Arial Rounded MT Bold", sans-serif;
}

/* ---------- 顶部导航 ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: var(--paw-blue);
  border-bottom: 6px solid var(--paw-dark);
  box-shadow: 0 2px 8px rgba(0,0,0,.15);
}
.topbar .inner {
  max-width: 900px; margin: 0 auto; padding: 10px 20px;
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
}
.topbar a {
  color: #fff; text-decoration: none; font-weight: 700;
  background: rgba(0,0,0,.22); padding: 6px 14px; border-radius: 8px;
  border: 2px solid rgba(255,255,255,.35);
}
.topbar a:hover { background: rgba(0,0,0,.4); }
.topbar .lesson-no {
  margin-left: auto; color: var(--ink); font-weight: 800;
  background: var(--sb-yellow); padding: 6px 14px; border-radius: 999px;
  border: 3px solid #fff; box-shadow: var(--shadow);
}

/* ---------- 标题区 ---------- */
.hero {
  margin: 24px 0; padding: 24px 28px;
  background: #fff; border: 4px solid var(--ink); border-radius: 16px;
  box-shadow: 8px 8px 0 rgba(0,0,0,.12);
  position: relative; overflow: hidden;
}
.hero::before {
  content: "ABC"; position: absolute; right: 10px; top: -6px;
  font-size: 84px; font-weight: 900; letter-spacing: -6px;
  color: var(--sb-yellow); opacity: .25; transform: rotate(8deg);
  font-family: "Comic Sans MS", "Chalkboard SE", sans-serif;
}
.hero h1 { margin: 0 0 8px; font-size: 30px; position: relative; }
.hero .unit-badge {
  display: inline-block; background: var(--mk-red); color: #fff;
  padding: 3px 12px; border-radius: 999px; font-size: 14px; font-weight: 700;
  margin-bottom: 8px;
}
.hero p { margin: 6px 0 0; color: #555; position: relative; }

/* ---------- 学习目标 ---------- */
.goals {
  background: #fff8dc; border: 3px dashed var(--sb-dark);
  border-radius: 12px; padding: 14px 20px; margin: 20px 0;
}
.goals h2 { margin: 0 0 6px; font-size: 19px; }
.goals ul { margin: 6px 0 2px; padding-left: 22px; }

/* ---------- 章节标题 ---------- */
h2.sec {
  margin: 40px 0 14px; font-size: 24px;
  padding: 8px 16px; color: #fff; border-radius: 10px;
  background: var(--paw-blue); border: 3px solid var(--paw-dark);
  box-shadow: var(--shadow);
}
h2.sec.word-title { background: var(--candy); border-color: #c05e1a; }
h2.sec.quiz-title { background: var(--mk-red); border-color: var(--mk-dark); }

/* ---------- 知识卡片 ---------- */
.card {
  background: #fff; border: 3px solid var(--ink); border-radius: 14px;
  padding: 18px 22px; margin: 18px 0;
  box-shadow: 6px 6px 0 rgba(0,0,0,.1);
}
.card h3 { margin: 0 0 10px; font-size: 20px; }
.card h3 .tag {
  font-size: 13px; vertical-align: middle; margin-left: 8px;
  background: var(--ice-blue); color: #0b4d63; padding: 2px 10px; border-radius: 999px;
}
.card h3 .tag.us {
  background: var(--gold); color: #6b4a00;
}

/* 主题故事框：四种动画角色皮肤 */
.story {
  border-radius: 12px; padding: 14px 18px; margin: 14px 0;
  border: 3px solid transparent;
}
.story.sb  { background: #fff9d6; border-color: var(--sb-dark); }   /* 海绵宝宝 / 派大星 */
.story.paw { background: #e3f2fd; border-color: var(--paw-dark); }  /* 汪汪队 */
.story.ice { background: #e8f8ff; border-color: var(--ice-dark); }  /* 艾莎 / 雪宝 */
.story.mk  { background: #ffecec; border-color: var(--mk-dark); }   /* 米奇 / 唐老鸭 */
.story .who { font-weight: 800; display: block; margin-bottom: 4px; }

/* 重点结论框 */
.key {
  background: linear-gradient(90deg, #fff9e0, #fff);
  border-left: 8px solid var(--sb-dark);
  padding: 12px 18px; margin: 14px 0; border-radius: 8px;
  font-weight: 700;
}
.key .k-icon { margin-right: 6px; }

/* 例句框 */
.example {
  background: #f0f7ff; border: 2px solid var(--paw-blue);
  border-radius: 10px; padding: 12px 18px; margin: 14px 0;
}
.example .ex-title { font-weight: 800; color: var(--paw-blue); }

/* 对话展示 */
.dialog {
  background: #fff; border: 2px solid #ccc; border-radius: 12px;
  padding: 12px 18px; margin: 12px 0;
}
.dialog p { margin: 6px 0; }
.dialog .spk { font-weight: 800; margin-right: 6px; }

table.nice {
  border-collapse: collapse; margin: 12px 0; width: 100%;
  background: #fff; font-size: 16px;
}
table.nice th, table.nice td {
  border: 2px solid var(--ink); padding: 8px 12px; text-align: center;
}
table.nice th { background: var(--paw-blue); color: #fff; }

/* ---------- 单词发音墙 ---------- */
.word-wall {
  display: flex; flex-wrap: wrap; gap: 10px; margin: 14px 0;
}
button.word-chip, button.speak {
  font: inherit; cursor: pointer;
  display: inline-flex; align-items: center; gap: 6px;
  background: #fff; border: 3px solid var(--candy); border-radius: 999px;
  padding: 6px 16px; box-shadow: 0 3px 0 rgba(192,94,26,.35);
  transition: transform .08s;
}
button.word-chip:hover, button.speak:hover { transform: translateY(-2px); background: #fff4ea; }
button.word-chip:active, button.speak:active { transform: translateY(1px); }
.word-chip b { font-size: 17px; color: #b34700; font-weight: 800; }
.word-chip i { font-style: normal; color: #666; font-size: 14px; }
.word-chip.us-word { border-color: var(--paw-blue); box-shadow: 0 3px 0 rgba(13,92,168,.35); }
.word-chip.us-word b { color: var(--paw-dark); }
.word-chip.speaking { background: var(--sb-yellow); }
button.speak { border-radius: 10px; }

.speak-tip {
  font-size: 14px; color: #777; background: #f4f4f4;
  border-radius: 8px; padding: 8px 14px; margin: 10px 0;
}

/* ---------- 练习题 ---------- */
.q {
  background: #fff; border: 3px solid var(--paw-blue); border-radius: 14px;
  padding: 16px 20px; margin: 16px 0;
  box-shadow: 5px 5px 0 rgba(30,136,229,.15);
}
.q .q-text { margin: 0 0 12px; font-weight: 700; }
.q .q-opts { display: flex; flex-wrap: wrap; gap: 10px; }
.q .q-opts button {
  font: inherit; font-weight: 700; cursor: pointer;
  background: #f4f9ff; color: var(--ink);
  border: 3px solid var(--paw-blue); border-radius: 10px;
  padding: 8px 18px; min-width: 84px;
  transition: transform .08s;
}
.q .q-opts button:hover { transform: translateY(-2px); background: #e3f2fd; }
.q.answered .q-opts button { cursor: default; opacity: .75; }
.q .q-opts button.right {
  background: var(--ok); border-color: #1d7030; color: #fff; opacity: 1 !important;
}
.q .q-opts button.wrong {
  background: var(--bad); border-color: #99271d; color: #fff; opacity: 1 !important;
}
.q .q-exp {
  display: none; margin-top: 12px; padding: 10px 14px;
  background: #fffbe6; border-left: 6px solid var(--sb-dark); border-radius: 6px;
  font-size: 15.5px;
}
.q.answered .q-exp { display: block; }
.q .verdict { display: none; font-weight: 800; margin-top: 10px; }
.q.answered .verdict { display: block; }
.q .verdict.good { color: var(--ok); }
.q .verdict.bad { color: var(--bad); }

/* 计分板 */
.scoreboard {
  position: sticky; bottom: 12px; margin: 24px 0 8px;
  background: var(--ink); color: #fff; border-radius: 999px;
  padding: 10px 22px; font-weight: 800; text-align: center;
  border: 3px solid var(--sb-yellow); box-shadow: 0 4px 14px rgba(0,0,0,.3);
}
.scoreboard .emoji { margin-right: 6px; }

/* ---------- 页脚导航 ---------- */
.pager {
  display: flex; justify-content: space-between; gap: 12px;
  margin-top: 48px; flex-wrap: wrap;
}
.pager a {
  flex: 1; min-width: 200px; text-align: center;
  background: var(--paw-blue); color: #fff; text-decoration: none;
  font-weight: 800; padding: 14px 18px; border-radius: 12px;
  border: 3px solid var(--paw-dark); box-shadow: var(--shadow);
}
.pager a.home { background: var(--mk-red); border-color: var(--mk-dark); }
.pager a:hover { filter: brightness(1.08); }
.pager a.disabled { pointer-events: none; opacity: .4; }

/* ---------- 首页目录 ---------- */
.unit-block { margin: 26px 0; }
.unit-block > h2 {
  font-size: 22px; margin: 0 0 12px;
  padding: 8px 16px; border-radius: 10px; color: #fff;
  background: var(--candy); border: 3px solid #c05e1a; box-shadow: var(--shadow);
}
.lesson-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 14px; }
.lesson-card {
  display: block; background: #fff; text-decoration: none; color: var(--ink);
  border: 3px solid var(--ink); border-radius: 14px; padding: 14px 18px;
  box-shadow: 5px 5px 0 rgba(0,0,0,.1); transition: transform .1s;
}
.lesson-card:hover { transform: translateY(-3px); border-color: var(--mk-red); }
.lesson-card .no {
  display: inline-block; background: var(--mk-red); color: #fff;
  font-weight: 800; border-radius: 8px; padding: 2px 10px; font-size: 14px;
  margin-bottom: 6px;
}
.lesson-card .no.us { background: var(--paw-blue); }
.lesson-card h3 { margin: 2px 0 6px; font-size: 18px; }
.lesson-card p { margin: 0; font-size: 14px; color: #666; }

.roadmap {
  background: #fff; border: 3px solid var(--ink); border-radius: 14px;
  padding: 18px 24px; margin: 18px 0; box-shadow: 6px 6px 0 rgba(0,0,0,.1);
}
.roadmap ol { padding-left: 24px; }

@media (max-width: 600px) {
  body { font-size: 16px; }
  .hero h1 { font-size: 24px; }
  .wrap { padding: 12px 14px 70px; }
}

/* ---------- 拼写挑战 ---------- */
.spelling {
  background: #fff; border: 3px solid var(--candy); border-radius: 14px;
  padding: 16px 20px; margin: 28px 0;
  box-shadow: 5px 5px 0 rgba(255,138,61,.18);
}
.spelling-head {
  display: grid; grid-template-columns: 1fr auto; gap: 4px 16px;
  align-items: center; margin-bottom: 12px;
}
.spelling h2 { margin: 0; font-size: 22px; }
.spelling p { margin: 0; color: #666; font-size: 14px; }
.spelling-score {
  grid-row: 1 / span 2; grid-column: 2;
  background: var(--sb-yellow); border: 3px solid var(--sb-dark);
  border-radius: 999px; padding: 6px 14px; font-weight: 800;
}
.spelling-list { display: grid; gap: 10px; }
.spelling-row {
  display: grid; grid-template-columns: 32px minmax(110px, 1fr) auto minmax(130px, 210px) auto minmax(100px, 1fr);
  gap: 8px; align-items: center;
  background: #fffaf0; border: 2px solid #ffd5a8; border-radius: 10px; padding: 8px;
}
.spelling-no {
  width: 28px; height: 28px; display: inline-grid; place-items: center;
  border-radius: 999px; background: var(--candy); color: #fff; font-weight: 800;
}
.spelling-meaning { font-weight: 800; }
.spelling-listen, .spelling-submit {
  font: inherit; cursor: pointer; border: 2px solid var(--candy);
  background: #fff; border-radius: 8px; padding: 5px 10px;
}
.spelling-input {
  width: 100%; font: inherit; border: 2px solid var(--paw-blue);
  border-radius: 8px; padding: 6px 8px;
}
.spelling-result { font-weight: 800; min-height: 1.5em; }
.spelling-row.right { border-color: var(--ok); background: #eefbf0; }
.spelling-row.right .spelling-result { color: var(--ok); }
.spelling-row.wrong { border-color: var(--bad); }
.spelling-row.wrong .spelling-result { color: var(--bad); }

/* ---------- 跟读打分 ---------- */
.speak-score-note { color: #777; margin-left: 6px; }
.speak-score-btn {
  display: inline-grid; place-items: center; width: 28px; height: 28px;
  border-radius: 999px; border: 2px solid var(--mk-red); background: #fff;
  cursor: pointer; line-height: 1; user-select: none;
}
.speak-score-btn:hover { background: #ffecec; }
.speak-score-btn.listening {
  background: var(--mk-red); color: #fff;
  animation: speak-pulse .7s infinite alternate;
}
.speak-score-result {
  font-size: 13px; font-weight: 800; color: #666; min-width: 0;
}
.speak-score-result.perfect, .speak-score-result.good { color: var(--ok); }
.speak-score-result.almost { color: #9a6a00; }
.speak-score-result.try { color: var(--bad); }
.speak-score-result.listening { color: var(--mk-red); }

@keyframes speak-pulse {
  from { transform: scale(1); }
  to { transform: scale(1.12); }
}

@media (max-width: 600px) {
  .spelling-head { grid-template-columns: 1fr; }
  .spelling-score { grid-row: auto; grid-column: auto; justify-self: start; }
  .spelling-row {
    grid-template-columns: 30px 1fr auto auto;
  }
  .spelling-input, .spelling-result {
    grid-column: 2 / -1;
  }
}