:root {
  --purple: #6B46C1;
  --purple-dark: #3B1D6E;
  --purple-light: #8B5CF6;
  --purple-bg: #F5F2FB;
  --gold: #C9A227;
  --text: #2A2438;
  --muted: #7A7488;
  --border: #E4E0EC;
  --bg: #FAF9FD;
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
  font-size: 15px; line-height: 1.7;
}
a { color: var(--purple); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }
.main { min-height: 70vh; padding: 24px 20px 48px; }
.muted { color: var(--muted); font-size: 13px; }

.site-header { background: #fff; border-bottom: 1px solid var(--border); }
.nav { display: flex; align-items: center; gap: 24px; height: 60px; }
.brand { font-weight: bold; font-size: 17px; color: var(--purple-dark); }
.main-nav { display: flex; gap: 18px; flex: 1; }
.main-nav a { color: var(--text); }
.nav-right { display: flex; gap: 12px; align-items: center; }

.site-footer { border-top: 1px solid var(--border); background: #fff; padding: 20px 0; text-align: center; color: var(--muted); font-size: 13px; }

.hero { background: linear-gradient(135deg, var(--purple-dark), var(--purple)); color: #fff; border-radius: 16px; padding: 56px 40px; margin-bottom: 36px; }
.hero h1 { font-size: 28px; margin: 0 0 10px; }
.hero .muted { color: #E3DAF7; margin-top: 0; }
.hero-inner { max-width: 640px; }

.section-title { font-size: 20px; margin: 18px 0; }

.course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 20px; }
.course-card { background: #fff; border: 1px solid var(--border); border-radius: 12px; overflow: hidden; color: var(--text); transition: box-shadow .15s; }
.course-card:hover { text-decoration: none; box-shadow: 0 4px 16px rgba(60,40,120,.12); }
.course-cover { height: 130px; background: var(--purple-bg); }
.course-cover img { width: 100%; height: 100%; object-fit: cover; }
.cover-ph { display: flex; align-items: center; justify-content: center; font-size: 42px; font-weight: bold; color: var(--purple); }
.cover-lg { width: 220px; height: 124px; border-radius: 8px; font-size: 48px; }
.course-card-body { padding: 14px 16px 16px; }
.course-card-body h3 { margin: 0 0 6px; font-size: 16px; }
.course-card-body p { margin: 0 0 6px; }
.course-meta { font-size: 13px; color: var(--muted); }

.page-narrow { max-width: 760px; }
.course-head { display: flex; gap: 20px; background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 20px; margin-bottom: 16px; }
.course-head img { width: 220px; height: 124px; object-fit: cover; border-radius: 8px; }
.course-head h1 { font-size: 22px; margin: 0 0 6px; }
.chapter-block { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 18px 20px; margin-bottom: 16px; }
.chapter-block h3, .chapter-block h4 { margin: 0 0 12px; font-size: 17px; }

.lesson-table { width: 100%; border-collapse: collapse; }
.lesson-table td { padding: 10px 8px; border-bottom: 1px solid var(--border); }
.lesson-table tr:last-child td { border-bottom: none; }
.lesson-link { font-weight: 500; }
.muted-right { text-align: right; }

.badge { display: inline-block; font-size: 12px; padding: 1px 8px; border-radius: 10px; margin-left: 6px; background: var(--purple-bg); color: var(--purple); }
.badge-free { background: #EAF3DE; color: #3B6D11; }
.badge-ok { background: #EAF3DE; color: #3B6D11; }

.notice { background: #FFF8E6; border: 1px solid #F0DFA8; border-radius: 8px; padding: 10px 14px; margin-bottom: 16px; font-size: 14px; }
.notice-ok { background: #EAF7EE; border-color: #B7E2C4; }

.play-layout { display: flex; gap: 24px; align-items: flex-start; }
.play-main { flex: 1; min-width: 0; }
.play-main h2 { margin: 0 0 4px; font-size: 19px; }
.video-box { width: 100%; border-radius: 12px; background: #000; aspect-ratio: 16/9; margin-top: 12px; }
.play-side { width: 280px; background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.play-side h3 { margin: 0 0 8px; font-size: 15px; }
.side-chapter { font-weight: 600; margin: 12px 0 4px; font-size: 14px; }
.side-lessons { list-style: none; padding: 0; margin: 0; }
.side-lessons li a { display: block; padding: 6px 8px; border-radius: 6px; font-size: 13px; color: var(--text); }
.side-lessons li a:hover { background: var(--purple-bg); text-decoration: none; }
.side-lessons li.current a { background: var(--purple); color: #fff; }
.side-lessons li.current a .badge-free { background: rgba(255,255,255,.25); color: #fff; }

.form-card { max-width: 400px; margin: 40px auto; background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 28px; }
.form-card h2 { margin-top: 0; }
label { display: block; font-size: 14px; margin: 14px 0 4px; color: var(--text); }
input[type=text], input[type=password], input[type=number], textarea, select {
  width: 100%; padding: 9px 12px; border: 1px solid var(--border); border-radius: 8px;
  font-size: 14px; background: #fff; color: var(--text);
}
input:focus, textarea:focus, select:focus { outline: 2px solid var(--purple-light); border-color: var(--purple-light); }
.inline-form input, .inline-form select { width: auto; }

.btn { display: inline-block; padding: 9px 18px; border-radius: 8px; border: 1px solid var(--purple); background: #fff; color: var(--purple); font-size: 14px; cursor: pointer; }
.btn:hover { text-decoration: none; background: var(--purple-bg); }
.btn-primary { background: var(--purple); color: #fff; }
.btn-primary:hover { background: var(--purple-dark); }
.btn-outline { border-color: var(--purple); color: var(--purple); background: transparent; }
.btn-sm { padding: 5px 14px; font-size: 13px; }
.btn-block { width: 100%; margin-top: 18px; }

.flash { background: var(--purple-bg); border: 1px solid #CDBCEC; color: var(--purple-dark); border-radius: 8px; padding: 10px 14px; margin-bottom: 16px; font-size: 14px; }

.admin-body { background: #F4F2F8; }
.admin-header { background: var(--purple-dark); }
.admin-header .brand, .admin-header .main-nav a, .admin-header .nav-right a { color: #EDE7FA; }
.stat-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 24px; }
.stat-card { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 18px; text-align: center; }
.stat-num { font-size: 30px; font-weight: bold; color: var(--purple); }
.panel { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 20px; margin-bottom: 20px; }
.panel h3, .panel h4 { margin: 0 0 12px; font-size: 16px; }
.data-table { width: 100%; border-collapse: collapse; background: #fff; }
.data-table th { text-align: left; font-size: 13px; color: var(--muted); padding: 8px; border-bottom: 2px solid var(--border); }
.data-table td { padding: 10px 8px; border-bottom: 1px solid var(--border); font-size: 14px; vertical-align: top; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.inline { display: inline; }
.link-btn { background: none; border: none; color: var(--purple); cursor: pointer; font-size: 14px; padding: 0; }
.link-btn:hover { text-decoration: underline; }
.link-btn.danger { color: #A32D2D; }
.check { display: inline-flex; align-items: center; gap: 5px; font-size: 14px; margin: 6px 12px 6px 0; cursor: pointer; }
.check input { width: auto; }
.check-group { margin: 8px 0; }
.stack-form { display: block; }
.add-lesson { margin-top: 10px; }
.add-lesson summary { cursor: pointer; color: var(--purple); font-size: 14px; }
.add-lesson form { margin-top: 10px; }
.ellipsis { max-width: 240px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.progress-bar { display: inline-block; vertical-align: middle; width: 90px; height: 8px; background: var(--border); border-radius: 4px; overflow: hidden; margin-right: 6px; }
.progress-fill { height: 100%; background: var(--purple); }
hr { border: none; border-top: 1px solid var(--border); margin: 16px 0; }

@media (max-width: 760px) {
  .play-layout { flex-direction: column; }
  .play-side { width: 100%; }
  .stat-row { grid-template-columns: repeat(2, 1fr); }
  .grid-2 { grid-template-columns: 1fr; }
  .course-head { flex-direction: column; }
}

/* ---- 免费资料专区 & 课程详情固定板块 ---- */
.free-sub { margin: -6px 0 16px; }
.free-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 16px; }
.free-card { position: relative; background: #fff; border: 1px solid #e5e7eb; border-radius: 12px; padding: 20px 16px; text-align: center; }
.free-tag { position: absolute; top: 12px; right: 12px; background: #fee2e2; color: #b91c1c; font-size: 12px; padding: 2px 8px; border-radius: 999px; font-weight: 600; }
.free-card h3 { margin: 6px 0 4px; font-size: 16px; }
.free-note { margin-top: 16px; text-align: center; color: #6b46c1; font-weight: 600; }
.btn-outline { display: inline-block; margin-top: 10px; padding: 6px 22px; border: 1px solid #6b46c1; color: #6b46c1; border-radius: 8px; text-decoration: none; font-weight: 600; }
.btn-outline:hover { background: #6b46c1; color: #fff; }
.info-panel { background: #faf9ff; border: 1px solid #e5e0f5; border-radius: 12px; padding: 20px 24px; margin: 20px 0; }
.panel-title { margin: 0 0 12px; font-size: 18px; }
.info-block { margin-bottom: 14px; }
.info-block h4 { margin: 0 0 6px; color: #6b46c1; font-size: 15px; }
.info-block .pre { white-space: pre-line; margin: 0; line-height: 1.8; }

/* ---- 微信领取弹窗 ---- */
.wx-modal { display: none; position: fixed; inset: 0; background: rgba(17, 12, 34, .55); z-index: 99; align-items: center; justify-content: center; }
.wx-modal.show { display: flex; }
.wx-box { background: #fff; border-radius: 16px; padding: 28px 36px; text-align: center; max-width: 320px; box-shadow: 0 20px 60px rgba(0,0,0,.25); }
.wx-title { font-size: 17px; font-weight: 700; margin: 0 0 14px; }
.wx-qr { width: 220px; height: 220px; object-fit: contain; border: 1px solid #e5e7eb; border-radius: 10px; }
.wx-note { color: #6b7280; margin: 12px 0 16px; font-size: 14px; }