/* ============ 基础 ============ */
:root {
  --brand: #0e7490;          /* 深青 */
  --brand-2: #14b8a6;        /* 青绿 */
  --accent: #f59e0b;         /* 泰国金 */
  --danger: #e11d48;         /* 红 */
  --ink: #0f172a;
  --ink-2: #475569;
  --ink-3: #94a3b8;
  --bg: #f1f5f9;
  --card: #ffffff;
  --line: #e2e8f0;
  --radius: 16px;
  --shadow: 0 1px 3px rgba(15, 23, 42, .06), 0 8px 24px -12px rgba(15, 23, 42, .12);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ============ Hero 头部 ============ */
.hero {
  background: linear-gradient(135deg, #0f172a 0%, #134e4a 55%, #065f46 100%);
  color: #fff;
  padding: 40px 20px 34px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(600px 200px at 80% -10%, rgba(245, 158, 11, .25), transparent 60%),
              radial-gradient(500px 220px at 10% 120%, rgba(20, 184, 166, .3), transparent 60%);
  pointer-events: none;
}
.hero-inner { max-width: 720px; margin: 0 auto; position: relative; z-index: 1; }
.hero-title { font-size: clamp(26px, 5vw, 36px); font-weight: 800; letter-spacing: 1px; }
.hero-subtitle { margin-top: 6px; font-size: 14px; color: rgba(255, 255, 255, .75); }

/* 进度条 */
.progress-wrap { margin: 22px auto 0; max-width: 420px; }
.progress-track {
  height: 8px; border-radius: 99px;
  background: rgba(255, 255, 255, .18); overflow: hidden;
}
.progress-fill {
  height: 100%; width: 0%;
  border-radius: 99px;
  background: linear-gradient(90deg, #fbbf24, #f59e0b);
  transition: width .4s ease;
}
.progress-text { display: block; margin-top: 8px; font-size: 13px; color: rgba(255, 255, 255, .85); font-weight: 600; }

/* Day 切换 */
.day-nav {
  margin-top: 18px;
  display: flex; align-items: center; justify-content: center; gap: 12px;
}
.nav-btn {
  width: 44px; height: 44px; border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, .3);
  background: rgba(255, 255, 255, .1);
  color: #fff; font-size: 18px; cursor: pointer;
  transition: background .15s, transform .1s;
}
.nav-btn:hover { background: rgba(255, 255, 255, .22); }
.nav-btn:active { transform: scale(.94); }
.nav-btn:disabled { opacity: .35; cursor: not-allowed; }
.day-select {
  min-width: 180px; height: 44px; padding: 0 14px;
  border-radius: 12px; border: none;
  background: #fff; color: var(--ink);
  font-size: 15px; font-weight: 600; cursor: pointer;
  box-shadow: var(--shadow);
}

/* ============ 内容区 ============ */
.content { max-width: 720px; margin: 0 auto; padding: 22px 16px 60px; }

.loading { text-align: center; color: var(--ink-3); padding: 60px 0; font-size: 15px; }

/* 课程头卡 */
.lesson-head {
  background: var(--card); border-radius: var(--radius);
  padding: 22px 22px 18px; box-shadow: var(--shadow);
  border-left: 5px solid var(--accent);
  margin-bottom: 18px;
}
.lesson-head .day-badge {
  display: inline-block; font-size: 12px; font-weight: 700;
  color: #92400e; background: #fef3c7;
  padding: 3px 10px; border-radius: 99px; letter-spacing: .5px;
}
.lesson-head h2 { margin-top: 10px; font-size: 22px; font-weight: 800; line-height: 1.4; }
.lesson-head .lesson-date { margin-top: 6px; font-size: 13px; color: var(--ink-3); }

/* 卡片通用 */
.card {
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); margin-bottom: 18px; overflow: hidden;
}
.card-head {
  display: flex; align-items: center; gap: 10px;
  padding: 14px 20px; border-bottom: 1px solid var(--line);
  font-size: 16px; font-weight: 800;
}
.card-head .ico { font-size: 20px; }
.card-body { padding: 18px 20px; }

/* ① 今日目标 */
.goal-card .card-body { background: linear-gradient(180deg, #f0fdfa, #fff); }
.goal-card p { font-size: 15px; color: var(--ink-2); }

/* ② 对话 */
.scene-desc {
  padding: 10px 14px; margin-bottom: 14px;
  background: #f8fafc; border-radius: 10px;
  font-size: 13px; color: var(--ink-2);
  border: 1px dashed var(--line);
}
.chat { display: flex; flex-direction: column; gap: 12px; }
.msg { display: flex; }
.msg.you { justify-content: flex-end; }
.msg.staff { justify-content: flex-start; }
.bubble {
  max-width: 82%; padding: 10px 14px; border-radius: 14px;
  font-size: 14.5px;
}
.msg.you .bubble {
  background: linear-gradient(135deg, #0e7490, #0f766e);
  color: #fff; border-bottom-right-radius: 4px;
}
.msg.staff .bubble {
  background: #f1f5f9; color: var(--ink);
  border: 1px solid var(--line); border-bottom-left-radius: 4px;
}
.bubble .en { font-weight: 700; }
.bubble .zh { font-size: 12.5px; opacity: .82; margin-top: 2px; }
.msg.you .bubble .zh { color: rgba(255, 255, 255, .85); }
.msg .role-tag {
  font-size: 11px; font-weight: 700; color: var(--ink-3);
  margin-bottom: 3px;
}
.msg.you .role-tag { text-align: right; }

/* ③ 必须会说 */
.say-item {
  display: flex; gap: 12px; padding: 10px 0;
  border-bottom: 1px dashed var(--line);
}
.say-item:last-child { border-bottom: none; }
.say-num {
  flex: none; width: 26px; height: 26px; border-radius: 8px;
  background: #ecfeff; color: var(--brand);
  font-size: 13px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.say-item .en { font-weight: 700; font-size: 15px; }
.say-item .zh { font-size: 13.5px; color: var(--ink-2); }
.say-item .note { font-size: 12.5px; color: var(--ink-3); margin-top: 2px; }

/* ④ 万能句型 */
.pattern-card {
  border: 1px solid var(--line); border-radius: 12px;
  padding: 14px 16px; margin-bottom: 12px;
  background: #fff;
}
.pattern-card:last-child { margin-bottom: 0; }
.pattern-main { font-size: 17px; font-weight: 800; color: var(--brand); }
.pattern-mean { font-size: 13.5px; color: var(--ink-2); margin-top: 2px; }
.pattern-examples { margin-top: 10px; }
.pattern-ex { padding: 6px 0; border-top: 1px dashed var(--line); font-size: 14px; }
.pattern-ex .en { font-weight: 600; }
.pattern-ex .zh { font-size: 12.5px; color: var(--ink-2); }
.pattern-note { margin-top: 10px; font-size: 12.5px; color: var(--ink-3); background: #f8fafc; padding: 8px 10px; border-radius: 8px; }

/* ⑤ 听力关键词 */
.listen-item { padding: 12px 0; border-bottom: 1px dashed var(--line); }
.listen-item:last-child { border-bottom: none; }
.listen-item .en { font-weight: 700; font-size: 15px; }
.listen-item .meaning { font-size: 13.5px; color: var(--ink-2); margin-top: 2px; }
.kw-chips { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.kw-chip {
  font-size: 12px; background: #fefce8; color: #854d0e;
  border: 1px solid #fde68a; padding: 2px 10px; border-radius: 99px;
}
.kw-chip b { color: #92400e; }

/* ⑥ 救命英语 */
.rescue-card { border-left: 5px solid var(--danger); }
.rescue-item {
  display: flex; gap: 10px; align-items: baseline; padding: 8px 0;
}
.rescue-item .en { font-weight: 700; font-size: 14.5px; color: #be123c; }
.rescue-item .zh { font-size: 13px; color: var(--ink-2); }

/* ⑦ 词汇 */
.vocab-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 10px;
}
.vocab-item {
  background: #f8fafc; border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 12px;
}
.vocab-item .word { font-weight: 800; font-size: 15px; color: var(--ink); }
.vocab-item .zh { font-size: 13px; color: var(--ink-2); }
.vocab-item .note { font-size: 11.5px; color: var(--ink-3); margin-top: 2px; }
.pronounce-tip {
  margin-top: 14px; padding: 10px 14px;
  background: #fff7ed; border: 1px solid #fed7aa; border-radius: 10px;
  font-size: 13px; color: #9a3412;
}

/* ⑧ 测试 */
.test-q { padding: 10px 0; border-bottom: 1px dashed var(--line); }
.test-q:last-child { border-bottom: none; }
.test-q .q-num {
  display: inline-block; min-width: 24px; font-weight: 800; color: var(--brand);
}
.test-toggle {
  margin-top: 14px; width: 100%;
  padding: 10px; border: none; border-radius: 10px;
  background: var(--brand); color: #fff;
  font-size: 14px; font-weight: 700; cursor: pointer;
  transition: background .15s;
}
.test-toggle:hover { background: #155e75; }
.test-answers { display: none; margin-top: 14px; }
.test-answers.show { display: block; }
.test-answer {
  padding: 8px 12px; margin-bottom: 6px;
  background: #f0fdf4; border: 1px solid #bbf7d0; border-radius: 8px;
  font-weight: 600; font-size: 14px;
}

/* ⑨ 角色扮演 */
.roleplay-card { border-left: 5px solid var(--accent); }
.roleplay-body { background: linear-gradient(180deg, #fffbeb, #fff); }
.roleplay-body p { font-size: 14.5px; }
.roleplay-hint {
  margin-top: 12px; font-size: 12.5px; color: var(--ink-3);
  background: #f8fafc; padding: 8px 12px; border-radius: 8px;
}

/* 空态 / 错误 */
.empty-state { text-align: center; padding: 60px 20px; color: var(--ink-3); }
.empty-state .big { font-size: 40px; margin-bottom: 10px; }

/* 页脚 */
.site-footer {
  text-align: center; padding: 26px 16px 40px;
  color: var(--ink-3); font-size: 12.5px;
}

/* 动画 */
.card, .lesson-head { animation: rise .35s ease both; }
@keyframes rise {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: none; }
}

/* ============ 响应式 ============ */
@media (max-width: 480px) {
  .hero { padding: 32px 14px 28px; }
  .bubble { max-width: 90%; }
  .day-select { min-width: 140px; }
  .content { padding: 16px 12px 50px; }
  .card-head { padding: 12px 16px; font-size: 15px; }
  .card-body { padding: 14px 16px; }
}