:root {
  --el-color-primary: #409eff;
  --el-color-primary-light-3: #79bbff;
  --el-color-primary-light-5: #a0cfff;
  --el-color-primary-light-7: #c6e2ff;
  --el-color-primary-light-8: #d9ecff;
  --el-color-primary-light-9: #ecf5ff;
  --el-color-primary-dark-2: #337ecc;
}
html.dark {
  --el-color-primary: #79bbff;
  --el-color-primary-light-3: #66b1ff;
  --el-color-primary-light-5: #4f9de6;
  --el-color-primary-light-7: #367bb8;
  --el-color-primary-light-8: #285d8c;
  --el-color-primary-light-9: #1d3f5f;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { height: 100%; margin: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", "Segoe UI", sans-serif;
  background: var(--el-bg-color);
  color: var(--el-text-color-primary);
  overscroll-behavior: none;
  transition: background 0.2s, color 0.2s;
}

[v-cloak] { display: none; }
#app { min-height: 100vh; min-height: 100dvh; }

#siteLoader {
  position: fixed; inset: 0; z-index: 9999;
  background: var(--el-bg-color);
  display: flex; align-items: center; justify-content: center;
  transition: opacity 0.4s ease, visibility 0.4s ease;
}
#siteLoader.is-hidden { opacity: 0; visibility: hidden; pointer-events: none; }
#siteLoader .loader-inner { text-align: center; color: var(--el-text-color-primary); }
#siteLoader .loader-progress { width: 80px; height: 80px; margin: 0 auto 16px; }
#siteLoader .loader-text { font-size: 14px; letter-spacing: 0.5px; opacity: 0.85; }

.app-container {
  width: 100%; max-width: 1440px; margin: 0 auto;
  min-height: 100vh; min-height: 100dvh;
  display: flex; flex-direction: column;
}
.desktop-sidebar { display: none; }
.sidebar-brand { padding: 6px 20px 24px; color: var(--el-text-color-secondary); }
.sidebar-brand strong { display: block; color: var(--el-color-primary); font-size: 22px; line-height: 1.2; }
.sidebar-brand span { display: block; margin-top: 6px; font-size: 13px; }
.desktop-sidebar .el-menu { border-right: 0; background: transparent; }
.desktop-sidebar .el-menu-item { height: 48px; margin: 4px 10px; border-radius: 6px; }
.desktop-sidebar .el-menu-item.is-active { background: var(--el-color-primary-light-9); color: var(--el-color-primary); font-weight: 600; }
.sidebar-account, .drawer-account { display: flex; align-items: center; gap: 10px; cursor: pointer; }
.sidebar-account { position: absolute; left: 22px; right: 22px; bottom: 24px; }
.drawer-menu { padding: 8px 14px; border: 0; background: transparent; }
.drawer-menu .el-menu-item { height: 48px; margin: 5px 0; padding: 0 16px; border-radius: 8px; color: var(--el-text-color-regular); }
.drawer-menu .el-menu-item:hover { background: var(--el-fill-color-light); color: var(--el-color-primary); }
.drawer-menu .el-menu-item.is-active { background: var(--el-color-primary-light-9); color: var(--el-color-primary); font-weight: 600; }
.drawer-menu .el-icon { margin-right: 10px; font-size: 18px; }
.drawer-account { margin: 18px 20px 10px; padding: 18px 10px 10px; border-top: 1px solid var(--el-border-color-light); }
.drawer-account:hover { background: var(--el-fill-color-light); border-radius: 8px; }
.account-avatar { flex: 0 0 auto; background: var(--el-color-primary); color: #fff; }
.account-summary { min-width: 0; flex: 1; }
.account-summary strong, .account-summary span { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.account-summary strong { color: var(--el-text-color-primary); font-size: 14px; }
.account-summary span { margin-top: 3px; color: var(--el-text-color-secondary); font-size: 12px; }
.account-panel .el-divider { margin: 24px 0 18px; }
.account-panel .el-button { min-width: 108px; }
.setting-note { margin-left: 12px; color: var(--el-text-color-secondary); font-size: 12px; }
.guide-step { padding: 12px 8px 8px; text-align: center; }
.guide-number { width: 48px; height: 48px; margin: 0 auto 14px; border-radius: 50%; background: var(--el-color-primary); color: #fff; font-size: 24px; line-height: 48px; font-weight: 700; }
.guide-step h3 { margin: 0 0 10px; color: var(--el-text-color-primary); font-size: 18px; }
.guide-step p { margin: 0; color: var(--el-text-color-secondary); line-height: 1.8; }

.auth-page {
  width: min(100%, 520px);
  margin: 28px auto 0;
}
.auth-heading { text-align: center; margin-bottom: 22px; }
.auth-mark {
  width: 52px; height: 52px; line-height: 52px; margin: 0 auto 12px;
  border-radius: 8px; background: var(--el-color-primary); color: #fff;
  font-size: 18px; font-weight: 700;
}
.auth-heading h1 { margin: 0; font-size: 24px; line-height: 1.35; color: var(--el-text-color-primary); }
.auth-heading p { margin: 8px 0 0; color: var(--el-text-color-secondary); font-size: 14px; }
.auth-card { border-radius: 8px; }
.auth-card-title { margin-bottom: 20px; font-size: 20px; font-weight: 600; text-align: center; }
.auth-submit { width: 100%; margin-top: 4px; }
.auth-links { display: flex; justify-content: center; gap: 12px; margin-top: 16px; }
.auth-alert { margin-bottom: 18px; }

.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 14px 8px; gap: 6px;
  position: sticky; top: 0;
  background: var(--el-bg-color);
  z-index: 10;
  border-bottom: 1px solid var(--el-border-color-light);
}
.topbar .brand {
  font-size: 14px; letter-spacing: 0;
  color: var(--el-text-color-secondary);
  white-space: nowrap;
}
.topbar .brand b { color: var(--el-text-color-primary); font-weight: 700; }
.hamburger-btn { font-size: 20px; color: var(--el-text-color-primary); }

.main-content {
  flex: 1; padding: 14px 14px 20px; overflow-y: auto;
}
.boot-placeholder { min-height: 60vh; }

.site-footer {
  padding: 16px 14px 24px;
  text-align: center;
  font-size: 12px;
  line-height: 1.9;
  color: var(--el-text-color-secondary);
  border-top: 1px solid var(--el-border-color-lighter);
}
.site-footer p { margin: 0; }
.site-footer-qq { color: var(--el-color-primary); font-weight: 600; user-select: all; }

.section-card { margin-bottom: 14px; }
.section-card .card-title {
  display: flex; align-items: center; gap: 6px;
  font-weight: 600; font-size: 14px;
}
.section-card .card-title .el-button { margin-left: auto; }
.range-radio { margin-bottom: 10px; display: flex; }
.curve-svg { width: 100%; max-width: 360px; display: block; margin: 0 auto; }
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }

.home-welcome { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-bottom: 20px; padding: 28px 30px; border-radius: 12px; background: linear-gradient(135deg, var(--el-color-primary-light-9), var(--el-bg-color)); border: 1px solid var(--el-border-color-light); }
.home-eyebrow { margin: 0 0 8px; color: var(--el-color-primary); font-size: 13px; font-weight: 600; }
.home-welcome h1 { margin: 0; color: var(--el-text-color-primary); font-size: 27px; }
.home-welcome p:last-child { margin: 10px 0 0; color: var(--el-text-color-secondary); }
.home-announcement { margin: -4px 0 18px; border: 1px solid var(--el-color-info-light-7); }
.home-announcement .el-alert__title { font-weight: 600; }
.home-stat-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-bottom: 18px; }
.home-stat-card { display: flex; align-items: center; gap: 13px; }
.home-stat-card > .el-icon { color: var(--el-color-primary); font-size: 26px; }
.home-stat-card strong, .home-stat-card span { display: block; }
.home-stat-card strong { color: var(--el-text-color-primary); font-size: 22px; line-height: 1.2; }
.home-stat-card span { margin-top: 4px; color: var(--el-text-color-secondary); font-size: 12px; }
.home-book-main { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 20px; }
.home-book-main h2 { margin: 0; color: var(--el-text-color-primary); font-size: 20px; }
.home-book-main p { margin: 8px 0 0; color: var(--el-text-color-secondary); }
.card-title { display: flex; align-items: center; gap: 6px; }
.card-title .el-button { margin-left: auto; }
.home-actions { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.home-actions .el-button { width: 100%; min-height: 58px; margin: 0; padding: 12px 10px; font-size: 15px; }
.home-actions .el-button .el-icon { margin-right: 6px; font-size: 20px; }
.home-actions .el-button span { line-height: 1.3; }
.settlement-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin-top: 8px; }
.settlement-grid div { padding: 14px 8px; border-radius: 8px; background: var(--el-fill-color-light); text-align: center; }
.settlement-grid strong, .settlement-grid span { display: block; }
.settlement-grid strong { color: var(--el-color-primary); font-size: 22px; }
.settlement-grid span { margin-top: 5px; color: var(--el-text-color-secondary); font-size: 12px; }
.settlement-list { max-height: 300px; margin-top: 18px; overflow-y: auto; border: 1px solid var(--el-border-color-lighter); border-radius: 8px; }
.settlement-list-title { padding: 10px 12px; color: var(--el-text-color-primary); font-weight: 600; background: var(--el-fill-color-light); }
.settlement-word { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 10px 12px; border-top: 1px solid var(--el-border-color-lighter); }
.settlement-word.is-starred { background: var(--el-color-warning-light-9); }
.settlement-word strong, .settlement-word span { display: block; }
.settlement-word strong { color: var(--el-text-color-primary); font-size: 14px; }
.settlement-word > div:first-child span { margin-top: 3px; color: var(--el-text-color-secondary); font-size: 12px; }
.settlement-tags { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 5px; }
.settlement-tag { padding: 2px 6px; color: var(--el-text-color-secondary); font-size: 11px; white-space: nowrap; background: var(--el-fill-color-light); border-radius: 4px; }
.settlement-tag.is-mastered { color: var(--el-color-success); background: var(--el-color-success-light-9); }
.settlement-tag.is-starred-tag { color: var(--el-color-warning-dark-2); background: var(--el-color-warning-light-8); }
.settlement-empty { padding: 18px; color: var(--el-text-color-secondary); text-align: center; font-size: 13px; }
.book-info { text-align: center; padding: 8px 0 14px; }
.book-info .book-name { font-size: 18px; font-weight: 700; color: var(--el-text-color-primary); }
.book-info .book-meta { font-size: 12px; color: var(--el-text-color-secondary); margin-top: 4px; }
.book-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; align-items: stretch; }
.book-grid .book-select-card { height: 100%; }
.book-select-card { overflow: hidden; border: 1px solid var(--el-border-color-light); transition: border-color .2s, box-shadow .2s, transform .2s; }
.book-select-card:hover { transform: translateY(-2px); }
.book-select-card.is-current { border-color: var(--el-color-primary); box-shadow: 0 4px 16px rgba(64, 158, 255, .12); }
.book-card-section { padding: 16px 18px; }
.book-intro-section { min-height: 104px; }
.book-progress-section { border-top: 1px solid var(--el-border-color-lighter); border-bottom: 1px solid var(--el-border-color-lighter); background: var(--el-fill-color-blank); }
.book-action-section { padding-top: 14px; padding-bottom: 18px; }
.book-section-label { margin-bottom: 10px; color: var(--el-text-color-secondary); font-size: 12px; font-weight: 600; letter-spacing: .04em; }
.book-description { min-height: 42px; margin: 0; color: var(--el-text-color-regular); font-size: 13px; line-height: 1.8; }
.book-radio { display: block; margin: 8px 0; }
.book-option { display: inline-block; }
.block-btn { width: 100%; margin-top: 8px; }
.word-list-card { margin-top: 18px; }
.word-list-switcher { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; color: var(--el-text-color-secondary); font-size: 13px; }
.admin-toolbar { display: flex; align-items: center; gap: 10px; margin-bottom: 16px; }
.admin-toolbar .el-input { max-width: 360px; }
.admin-toolbar .el-select { width: 240px; }
.admin-stat-grid { margin-bottom: 18px; }
@media (max-width: 640px) {
  .admin-toolbar { align-items: stretch; flex-direction: column; }
  .admin-toolbar .el-input, .admin-toolbar .el-select { width: 100%; max-width: none; }
}
.word-list-tools { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.word-list-tools .el-input { width: min(360px, 100%); }
.word-list-summary { margin: 14px 0 8px; color: var(--el-text-color-secondary); font-size: 12px; }
.word-list-item { border: 1px solid var(--el-border-color-lighter); border-radius: 6px; margin-top: 8px; overflow: hidden; background: var(--el-bg-color); }
.word-list-item.is-starred { border-color: var(--el-color-warning-light-5); background: var(--el-color-warning-light-9); }
.word-list-row { min-height: 58px; padding: 10px 14px; display: flex; align-items: center; justify-content: space-between; gap: 12px; cursor: pointer; }
.word-list-main { min-width: 0; display: flex; flex-direction: column; justify-content: center; gap: 4px; }
.word-list-main strong { color: var(--el-text-color-primary); font-size: 16px; }
.word-list-status { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.word-star { color: var(--el-text-color-placeholder); font-size: 19px; cursor: pointer; }
.word-star.is-active { color: var(--el-color-warning); }
.word-expand-icon { color: var(--el-text-color-placeholder); transition: transform .2s; }
.word-list-item.is-expanded .word-expand-icon { transform: rotate(90deg); }
.word-list-detail { padding: 12px 14px 14px; border-top: 1px solid var(--el-border-color-lighter); background: var(--el-fill-color-lighter); }
.word-detail-line { display: flex; gap: 12px; margin-bottom: 8px; color: var(--el-text-color-secondary); font-size: 13px; }
.word-detail-line span { width: 38px; flex-shrink: 0; }
.word-detail-line strong { color: var(--el-text-color-primary); font-weight: 500; }
.word-detail-actions { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
.word-list-pagination { display: flex; justify-content: center; margin-top: 18px; }

.captcha-row { display: flex; gap: 8px; align-items: center; }
.captcha-img { cursor: pointer; border-radius: 6px; height: 32px; vertical-align: middle; }
.captcha-dialog-row .captcha-img { height: 40px; min-width: 120px; border: 1px solid var(--el-border-color); }
.captcha-dialog-tip { margin: 0; font-size: 12px; line-height: 1.7; color: var(--el-text-color-secondary); }
.forgot-question { font-weight: 600; color: var(--el-color-primary); }
.smtp-port-row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.smtp-port-row .el-input-number { width: 150px; }

.reminder-next-time { font-weight: 600; color: var(--el-color-primary); font-size: 15px; }
.reminder-tips { margin: 0; padding-left: 20px; color: var(--el-text-color-regular); font-size: 13px; line-height: 2; }
.reminder-tips li { list-style: disc; }
.cron-url-box { background: var(--el-fill-color-light); border: 1px solid var(--el-border-color); border-radius: 6px; padding: 10px 12px; word-break: break-all; font-family: Consolas, Monaco, monospace; font-size: 13px; line-height: 1.7; margin: 10px 0; }
.cron-code-block { background: #1e1e1e; color: #d4d4d4; border-radius: 6px; padding: 14px 16px; font-family: Consolas, Monaco, monospace; font-size: 12.5px; line-height: 1.8; overflow-x: auto; margin: 8px 0 14px; white-space: pre; }
.cron-steps { margin: 0; padding-left: 22px; color: var(--el-text-color-regular); font-size: 13px; line-height: 2; }
.cron-steps li { list-style: decimal; }

.drawer-footer { padding: 12px 20px; border-top: 1px solid var(--el-border-color-light); }

.study-primary-actions, .study-state-actions, .study-extra-actions { display: grid; gap: 12px; margin-top: 14px; }
.study-primary-actions { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.study-state-actions, .study-extra-actions { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.study-primary-actions .el-button,
.study-state-actions .el-button,
.study-extra-actions .el-button,
.exit-study-btn { width: 100%; min-height: 48px; margin: 0; border-radius: 8px; transition: transform .18s ease, box-shadow .18s ease; }
.study-primary-actions .el-button:hover,
.study-state-actions .el-button:hover,
.study-extra-actions .el-button:hover,
.exit-study-btn:hover { transform: translateY(-1px); box-shadow: var(--el-box-shadow-light); }
.study-prev-btn { background: var(--el-fill-color-light); }
.study-master-btn { border-color: var(--el-color-success-light-5); }
.study-next-btn { font-size: 15px; font-weight: 600; box-shadow: 0 4px 10px rgba(64, 158, 255, .2); }
.study-state-actions .el-button:first-child { border-color: var(--el-color-warning-light-5); }
.study-state-actions .el-button:last-child { border-color: var(--el-color-danger-light-5); }
.study-extra-actions .el-button { background: var(--el-fill-color-blank); }
.exit-study-btn { margin-top: 18px; }

.quiz-question { text-align: center; padding: 18px 8px; }
.quiz-q-text { font-size: clamp(22px, 6vw, 32px); font-weight: 700; color: var(--el-text-color-primary); }
.quiz-sub { font-size: 12px; color: var(--el-text-color-secondary); margin-top: 4px; }
.quiz-ipa { font-size: 13px; color: var(--el-text-color-secondary); margin-top: 4px; font-family: "Times New Roman", serif; }
.quiz-recall { display: flex; gap: 8px; justify-content: center; margin: 18px 0; }
.quiz-feedback { text-align: center; font-size: 13px; padding: 10px; color: var(--el-text-color-secondary); }
.quiz-nav { margin-top: 12px; }

@media (min-width: 960px) {
  .app-container { max-width: none; padding-left: 232px; }
  .app-container.is-guest { max-width: 1440px; padding-left: 0; margin: 0 auto; }
  .app-container.is-guest .topbar { padding-left: 14px; }
  .topbar { padding-left: 32px; }
  .hamburger-btn { display: none; }
  .desktop-sidebar {
    display: block; position: fixed; z-index: 20; top: 0; bottom: 0; left: 0;
    width: 232px; padding: 28px 12px 88px; overflow-y: auto;
    background: var(--el-bg-color-overlay); border-right: 1px solid var(--el-border-color-light);
  }
  .main-content { padding: 28px 56px 40px; }
  .auth-page { margin-top: 48px; }
}

@media (min-width: 768px) and (max-width: 959px) {
  .home-stat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .home-actions { grid-template-columns: repeat(2, 1fr); }
  .main-content { padding: 28px 40px 40px; }
  .auth-page { margin-top: 48px; }
}

@media (max-width: 767px) {
  .study-primary-actions { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; }
  .study-primary-actions .el-button { min-height: 46px; padding: 8px 4px; }
  .study-state-actions, .study-extra-actions { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .study-state-actions .el-button, .study-extra-actions .el-button { min-width: 0; }
  .settlement-word { align-items: flex-start; flex-direction: column; }
  .settlement-tags { justify-content: flex-start; }
  .book-grid { grid-template-columns: 1fr; gap: 12px; }
  .word-list-switcher { align-items: stretch; flex-direction: column; }
  .word-list-switcher .el-select { width: 100% !important; }
  .word-list-tools { align-items: stretch; }
  .word-list-tools .el-input { width: 100%; }
  .word-list-tools .el-radio-group { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .word-list-tools .el-radio-button, .word-list-tools .el-radio-button__inner { width: 100%; }
  .word-list-tools .el-radio-button__inner { padding-left: 8px; padding-right: 8px; }
  .word-list-status .el-tag { display: none; }
  .page-heading h2 { font-size: 21px; }
  .main-content { padding: 16px 14px 24px; }
  .topbar { padding: 10px 14px 8px; }
}

@media (max-width: 480px) {
  .auth-page { margin-top: 12px; }
  .auth-heading h1 { font-size: 21px; }
  .auth-card { --el-card-padding: 18px; }
  .main-content { padding: 12px 10px 18px; }
  .topbar { padding: 10px 10px 6px; }
}