/* ==========================================================================
   麻豆影院 · 站点样式表
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. base —— 变量、重置、排版基础
   -------------------------------------------------------------------------- */

:root {
  --bg: #0a0c10;
  --panel: #141920;
  --panel-2: #1b222b;
  --line: #2a3441;
  --line-soft: #202832;
  --text: #eef2f6;
  --text-2: #a7b0bb;
  --text-3: #7d8794;
  --red: #e5484d;
  --red-soft: rgba(229, 72, 77, 0.14);
  --green: #45d483;
  --green-soft: rgba(69, 212, 131, 0.12);
  --light: #f4f6f8;
  --radius: 6px;
  --radius-sm: 4px;
  --shell: 1180px;
  --main-col: 820px;
  --aside-col: 300px;
  --gap-layout: 40px;
  --header-h: 64px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
p,
figure,
dl,
dd,
ul,
ol {
  margin: 0;
}

ul,
ol {
  padding: 0;
  list-style: none;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 0;
}

a {
  color: var(--text);
  text-decoration: none;
  text-underline-offset: 3px;
}

a:hover {
  color: #ffffff;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
  width: 100%;
}

:focus-visible {
  outline: 2px solid var(--red);
  outline-offset: 2px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -60px;
  left: 16px;
  z-index: 60;
  padding: 10px 16px;
  background-color: var(--light);
  color: #10141a;
  border-radius: var(--radius-sm);
  font-size: 14px;
  transition: top 0.18s ease;
}

.skip-link:focus {
  top: 10px;
}

/* --------------------------------------------------------------------------
   2. layout —— 页头 / 主容器 / 内页骨架 / 页脚
   -------------------------------------------------------------------------- */

/* 页头：全站统一高度与粘性定位 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: rgba(10, 12, 16, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  width: 100%;
  max-width: var(--shell);
  min-height: var(--header-h);
  margin: 0 auto;
  padding: 0 20px;
}

.brand {
  flex: 0 0 auto;
  font-size: 19px;
  font-weight: 700;
  color: var(--text);
  white-space: nowrap;
}

.brand::after {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-left: 8px;
  vertical-align: 3px;
  border-radius: 50%;
  background-color: var(--red);
}

.brand:hover {
  color: var(--text);
}

/* 主导航：桌面横排 */
.site-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 4px;
}

.nav-list li {
  display: flex;
}

.nav-list a {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  font-size: 15px;
  color: var(--text-2);
  border-radius: var(--radius-sm);
  transition: color 0.16s ease, background-color 0.16s ease;
}

.nav-list a:hover {
  color: var(--text);
  background-color: var(--panel);
}

.nav-list a.is-current {
  color: var(--text);
  font-weight: 600;
  background-color: var(--panel);
}

.nav-list a.is-current::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  bottom: 12px;
  width: 2px;
  border-radius: 2px;
  background-color: var(--red);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 44px;
  height: 44px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}

.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--text);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

/* 主内容骨架 */
.site-main {
  display: block;
  width: 100%;
}

.inner-main {
  padding: 28px 0 72px;
}

.container,
.page-container {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
}

/* 内页双栏：主内容在前，aside 在后 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, var(--main-col)) minmax(0, var(--aside-col));
  gap: var(--gap-layout);
  align-items: start;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
}

.page-layout .page-content,
.page-layout .content-main,
.page-layout .page-primary {
  min-width: 0;
}

.page-layout .page-aside,
.page-layout .content-aside {
  min-width: 0;
  position: sticky;
  top: calc(var(--header-h) + 20px);
}

/* 面包屑：全站统一 */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  font-size: 13px;
  color: var(--text-3);
}

.breadcrumb a {
  color: var(--text-2);
}

.breadcrumb a:hover {
  color: var(--text);
  text-decoration: underline;
}

.breadcrumb-sep {
  color: var(--line);
}

.breadcrumb-current {
  color: var(--text-2);
}

/* 页面标题区 */
.page-header {
  margin-bottom: 22px;
}

.page-title {
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.25;
  font-weight: 700;
  color: var(--text);
}

/* 页脚：全站统一 */
.site-footer {
  border-top: 1px solid var(--line);
  background-color: #0c0f14;
  padding: 48px 0 32px;
}

.footer-inner {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
}

.footer-groups {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 32px;
}

.footer-group h2 {
  margin-bottom: 14px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-3);
}

.footer-group ul {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-group a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-size: 15px;
  color: var(--text-2);
}

.footer-group a:hover {
  color: var(--text);
  text-decoration: underline;
}

.footer-bottom {
  margin-top: 36px;
  padding-top: 22px;
  border-top: 1px solid var(--line-soft);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 18px;
}

.footer-brand {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.footer-slogan {
  font-size: 14px;
  color: var(--text-2);
}

.footer-copy {
  font-size: 13px;
  color: var(--text-3);
}

/* --------------------------------------------------------------------------
   3. components —— 通用组件
   -------------------------------------------------------------------------- */

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: background-color 0.16s ease, border-color 0.16s ease, color 0.16s ease;
}

.btn-primary {
  background-color: var(--red);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: #f05459;
  color: #ffffff;
}

.btn-ghost {
  border-color: var(--line);
  color: var(--text);
  background-color: transparent;
}

.btn-ghost:hover {
  border-color: #3d4a5a;
  background-color: var(--panel);
  color: var(--text);
}

/* 字幕式小标签 */
.subtitle-tag,
.section-tag,
.eyebrow,
.section-label,
.kicker {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 2px;
  background-color: var(--light);
  color: #10141a;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.6;
}

.eyebrow,
.section-label {
  background-color: var(--red-soft);
  color: #ff9b9e;
}

.kicker {
  background-color: var(--green-soft);
  color: var(--green);
}

/* 模块标题组 */
.section-head {
  margin-bottom: 24px;
}

.section-head h2 {
  font-size: 26px;
  line-height: 1.35;
  font-weight: 700;
  color: var(--text);
}

.section-desc {
  margin-top: 8px;
  max-width: 70ch;
  font-size: 15px;
  color: var(--text-2);
}

.section-intro,
.section-note,
.page-lead,
.page-lede,
.error-lead {
  max-width: 70ch;
  font-size: 16px;
  color: var(--text-2);
}

.page-lead,
.page-lede {
  margin-top: 10px;
}

.section-intro,
.section-note {
  margin-bottom: 18px;
}

/* 结论摘要框 */
.summary-box {
  position: relative;
  margin: 0 0 32px;
  padding: 22px 24px 22px 26px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.summary-box::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22px;
  width: 3px;
  height: 18px;
  border-radius: 0 2px 2px 0;
  background-color: var(--red);
}

.summary-box h2,
.summary-box .summary-title {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-2);
  margin-bottom: 10px;
}

.summary-box p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

.summary-box p + p {
  margin-top: 10px;
}

/* 内页正文块间距 */
.content-section,
.section-block,
.content-block {
  margin-bottom: 44px;
}

.content-section h2,
.section-block h2,
.content-block h2,
.faq-group h2,
.glossary-quick h2,
.term-objects h2,
.term-markers h2,
.term-pairs h2 {
  font-size: 24px;
  line-height: 1.4;
  font-weight: 700;
  margin-bottom: 12px;
}

.content-section p,
.section-block p,
.content-block p {
  max-width: 70ch;
  color: var(--text-2);
}

.content-section p + p,
.content-block p + p {
  margin-top: 12px;
}

/* 图片容器 */
.media-figure,
.content-figure,
.term-figure,
.article-media,
.section-figure {
  margin: 20px 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--panel);
}

.media-figure img,
.content-figure img,
.term-figure img,
.article-media img,
.section-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: var(--panel-2);
}

.media-figure figcaption,
.content-figure figcaption,
.term-figure figcaption,
.article-media figcaption,
.section-figure figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-3);
  border-top: 1px solid var(--line-soft);
}

/* 侧栏 */
.aside-block {
  padding: 20px;
  margin-bottom: 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.aside-block h2 {
  margin-bottom: 12px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-2);
}

.aside-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.aside-list a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 6px 0;
  font-size: 15px;
  color: var(--text);
  border-bottom: 1px dashed var(--line-soft);
}

.aside-list li:last-child a {
  border-bottom: 0;
}

.aside-list a:hover {
  color: #ffffff;
  text-decoration: underline;
}

.aside-desc {
  margin-top: 10px;
  font-size: 14px;
  color: var(--text-3);
}

/* 通用链接箭头 */
.link-more,
.card-link,
.entry-link,
.feedback-link a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 44px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  text-decoration: underline;
  text-decoration-color: var(--red);
  text-decoration-thickness: 2px;
  text-underline-offset: 5px;
}

.link-more::after,
.card-link::after,
.entry-link::after {
  content: "→";
  color: var(--red);
  font-weight: 400;
}

.link-more:hover,
.card-link:hover,
.entry-link:hover,
.feedback-link a:hover {
  color: #ffffff;
}

/* 表格通用 */
.table-wrap,
.table-scroll,
.setting-table-wrap {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--panel);
}

.compare-table,
.setting-table {
  min-width: 560px;
  font-size: 15px;
}

.compare-table th,
.compare-table td,
.setting-table th,
.setting-table td {
  padding: 12px 16px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line-soft);
  border-right: 1px solid var(--line-soft);
}

.compare-table th:last-child,
.compare-table td:last-child,
.setting-table th:last-child,
.setting-table td:last-child {
  border-right: 0;
}

.compare-table tbody tr:last-child th,
.compare-table tbody tr:last-child td,
.setting-table tbody tr:last-child th,
.setting-table tbody tr:last-child td {
  border-bottom: 0;
}

.compare-table thead th,
.setting-table thead th {
  background-color: var(--panel-2);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-2);
}

.compare-table tbody th,
.setting-table tbody th {
  font-weight: 600;
  color: var(--text);
  background-color: rgba(27, 34, 43, 0.6);
}

.compare-table td,
.setting-table td {
  color: var(--text-2);
}

/* 定义列表通用 */
.cond-list,
.condition-list,
.form-list,
.term-list,
.marker-list {
  display: grid;
  gap: 0;
}

/* 通用列表 */
.method-list,
.pitfall-list,
.level-list,
.combo-list,
.tip-list,
.feedback-list,
.point-list,
.rule-list,
.scope-list,
.error-tips {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.method-list li,
.pitfall-list li,
.level-list li,
.combo-list li,
.tip-list li,
.feedback-list li,
.point-list li,
.rule-list li,
.scope-list li,
.error-tips li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.method-list li::before,
.level-list li::before,
.combo-list li::before,
.tip-list li::before,
.point-list li::before,
.rule-list li::before,
.scope-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--green);
}

.pitfall-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--red);
}

.feedback-list li::before,
.error-tips li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--red);
}

.feedback-list strong {
  color: var(--text);
  font-weight: 600;
}

/* --------------------------------------------------------------------------
   4. pages —— 首页
   -------------------------------------------------------------------------- */

.home-main {
  display: block;
}

/* 4.1 作品集式首屏 */
.hero {
  padding: 40px 0 56px;
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  gap: 40px;
  align-items: center;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
}

.hero-media {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--panel);
}

.hero-media img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.hero-caption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-3);
  border-top: 1px solid var(--line-soft);
}

.hero-copy {
  min-width: 0;
}

.hero-copy h1 {
  margin: 14px 0 14px;
  font-size: clamp(30px, 3.6vw, 44px);
  line-height: 1.22;
  font-weight: 700;
  color: var(--text);
}

.hero-lead {
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-2);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.hero-index {
  margin-top: 26px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.hero-index-title {
  margin-bottom: 8px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-3);
}

.hero-index-list {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
}

.hero-index-list li {
  display: flex;
}

.hero-index-list a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-size: 14px;
  color: var(--text-2);
}

.hero-index-list a:hover {
  color: var(--text);
  text-decoration: underline;
}

/* 4.2 门户导航 */
.portal,
.featured,
.compare,
.theme-band,
.basics-three,
.advanced-preview,
.glossary-preview,
.ask-first {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 52px 20px;
}

.portal {
  border-bottom: 1px solid var(--line);
}

.portal-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.portal-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
  padding: 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.portal-group h3 {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--red);
}

.portal-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.portal-list li {
  display: flex;
}

.portal-card {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 100%;
  min-height: 44px;
  padding: 12px 14px;
  background-color: var(--panel-2);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.portal-card:hover {
  border-color: #3d4a5a;
  background-color: #222b36;
}

.portal-card .portal-name {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.portal-card .portal-name::after {
  content: "→";
  color: var(--text-3);
  font-weight: 400;
}

.portal-task {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-3);
}

/* 4.3 精选专题条目 */
.featured {
  border-bottom: 1px solid var(--line);
}

.featured-item {
  display: grid;
  grid-template-columns: minmax(0, 320px) minmax(0, 1fr);
  gap: 24px;
  padding: 24px 0;
  border-top: 1px solid var(--line-soft);
}

.featured-item:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.featured-item:last-of-type {
  padding-bottom: 0;
}

.featured-media {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--panel);
  align-self: start;
}

.featured-media img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.subtitle-caption {
  display: block;
  padding: 8px 12px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-2);
  background-color: var(--panel-2);
  border-top: 1px solid var(--line-soft);
}

.featured-body {
  min-width: 0;
}

.featured-body h3 {
  font-size: 20px;
  line-height: 1.4;
  font-weight: 700;
  color: var(--text);
}

.featured-intro {
  margin-top: 8px;
  max-width: 62ch;
  font-size: 15px;
  color: var(--text-2);
}

.cond-list {
  grid-template-columns: minmax(96px, max-content) minmax(0, 1fr);
  gap: 0;
  margin: 16px 0 14px;
  border-top: 1px solid var(--line-soft);
}

.cond-list dt,
.cond-list dd {
  padding: 8px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 14px;
  line-height: 1.7;
}

.cond-list dt {
  color: var(--text-3);
  padding-right: 12px;
}

.cond-list dd {
  color: var(--text);
}

/* 4.4 专题条件对照表 */
.compare {
  border-bottom: 1px solid var(--line);
}

/* 4.5 主题索引带 */
.theme-band {
  border-bottom: 1px solid var(--line);
}

.theme-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.theme-item {
  display: flex;
  min-width: 0;
}

.theme-link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 100%;
  padding: 16px 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--red);
  border-radius: var(--radius);
  transition: background-color 0.16s ease, border-color 0.16s ease;
}

.theme-link:hover {
  background-color: var(--panel-2);
  border-color: #3d4a5a;
  border-left-color: var(--red);
}

.theme-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.theme-scene {
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-3);
}

/* 4.6 观看基础三步 */
.basics-three {
  border-bottom: 1px solid var(--line);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.step-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 22px 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step-card .step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: var(--radius-sm);
  background-color: var(--red-soft);
  color: #ff9b9e;
  font-size: 14px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.step-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
}

.step-card p {
  flex: 1 1 auto;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

/* 4.7 进阶方法预览 */
.advanced-preview {
  border-bottom: 1px solid var(--line);
}

.advanced-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.advanced-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-width: 0;
  padding: 22px 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.advanced-col h3 {
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.advanced-col .link-more {
  margin-top: auto;
}

.advanced-col-warn {
  border-color: rgba(229, 72, 77, 0.4);
}

.advanced-col-warn h3 {
  color: #ff9b9e;
}

/* 4.8 术语速查预览 */
.glossary-preview {
  border-bottom: 1px solid var(--line);
}

.glossary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.glossary-item {
  display: flex;
  min-width: 0;
}

.glossary-link {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 100%;
  min-height: 44px;
  padding: 14px 16px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.glossary-link:hover {
  border-color: #3d4a5a;
  background-color: var(--panel-2);
}

.glossary-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.glossary-use {
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-3);
}

/* 4.9 先问再进问题清单 */
.ask-first {
  border-bottom: 1px solid var(--line);
}

.ask-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line-soft);
}

.ask-item {
  display: flex;
  border-bottom: 1px solid var(--line-soft);
}

.ask-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  min-height: 52px;
  padding: 12px 4px;
  transition: color 0.16s ease;
}

.ask-question {
  font-size: 16px;
  color: var(--text);
}

.ask-target {
  flex: 0 0 auto;
  font-size: 13px;
  color: var(--text-3);
}

.ask-target::after {
  content: "→";
  margin-left: 6px;
  color: var(--red);
}

.ask-link:hover .ask-question {
  color: #ffffff;
  text-decoration: underline;
}

/* --------------------------------------------------------------------------
   5. pages —— 内页业务模块
   -------------------------------------------------------------------------- */

/* 5.1 主题页 topics */
.page-hero {
  margin-bottom: 28px;
}

.page-hero .section-tag {
  margin-bottom: 10px;
}

.page-layout .page-hero {
  margin-bottom: 0;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.topic-card h3 {
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.topic-card p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.topic-card .card-link {
  margin-top: auto;
}

.form-list {
  border-top: 1px solid var(--line);
}

.form-item {
  display: grid;
  grid-template-columns: minmax(120px, max-content) minmax(0, 1fr);
  gap: 4px 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-soft);
}

.form-item dt {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.form-item dd {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.form-item dd.form-tags {
  grid-column: 2;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}

.form-tags .tag {
  display: inline-block;
  padding: 2px 8px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-2);
  background-color: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 2px;
}

.step-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.step-item {
  min-width: 0;
  padding: 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

/* 5.2 基础页 basics */
.page-head {
  margin-bottom: 24px;
}

.page-head .kicker {
  margin-bottom: 10px;
}

.conclusion-box {
  position: relative;
  margin-bottom: 36px;
  padding: 22px 24px 22px 26px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.conclusion-box::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22px;
  width: 3px;
  height: 18px;
  border-radius: 0 2px 2px 0;
  background-color: var(--red);
}

.conclusion-box h2 {
  margin-bottom: 10px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-2);
}

.conclusion-box p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

.conclusion-box p + p {
  margin-top: 10px;
}

.structure-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 8px;
}

.structure-item {
  min-width: 0;
  padding: 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.structure-item h3 {
  margin-bottom: 6px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.structure-item p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.structure-item p + p {
  margin-top: 6px;
}

.check-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.check-card {
  min-width: 0;
  padding: 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-top: 2px solid var(--green);
  border-radius: var(--radius);
}

.check-card h3 {
  margin-bottom: 6px;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.check-card p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.check-card p + p {
  margin-top: 6px;
}

.misread-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.misread-item {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.misread-wrong,
.misread-right {
  min-width: 0;
  padding: 16px 18px;
  font-size: 15px;
  line-height: 1.75;
}

.misread-wrong {
  background-color: rgba(229, 72, 77, 0.08);
  border-right: 1px solid var(--line);
  color: #f0b6b8;
}

.misread-right {
  background-color: rgba(69, 212, 131, 0.07);
  color: #b8e8cd;
}

/* 5.3 进阶页 advanced */
.page-title-block {
  margin-bottom: 24px;
}

.page-title-block .section-tag {
  margin-bottom: 10px;
}

.two-column,
.three-column {
  display: grid;
  gap: 18px;
  margin-top: 18px;
}

.two-column {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.three-column {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.column {
  min-width: 0;
  padding: 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.column h3 {
  margin-bottom: 10px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.level-list .level-name {
  font-weight: 600;
  color: var(--text);
}

.combo-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 10px;
}

.combo-tags .tag {
  display: inline-block;
  padding: 2px 8px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-2);
  background-color: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 2px;
}

.step-flow {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.step-flow .step-item {
  position: relative;
  padding-top: 22px;
}

.step-flow .step-item::before {
  content: "";
  position: absolute;
  left: 18px;
  top: 12px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--red);
}

.order-judge,
.order-record,
.order-review {
  min-width: 0;
}

.mistake-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.mistake-item {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.mistake-wrong,
.mistake-fix {
  min-width: 0;
  padding: 16px 18px;
  font-size: 15px;
  line-height: 1.75;
}

.mistake-wrong {
  background-color: rgba(229, 72, 77, 0.08);
  border-right: 1px solid var(--line);
  color: #f0b6b8;
}

.mistake-fix {
  background-color: rgba(69, 212, 131, 0.07);
  color: #b8e8cd;
}

/* 5.4 术语页 glossary */
.term-list {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.term-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.term-item dt {
  margin-bottom: 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.term-item dd {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-2);
}

.term-item dd + dd {
  margin-top: 6px;
}

.term-objects {
  margin-bottom: 44px;
}

.object-item {
  padding: 18px 0;
  border-bottom: 1px solid var(--line-soft);
}

.object-item:first-of-type {
  border-top: 1px solid var(--line-soft);
}

.object-item h3 {
  margin-bottom: 6px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.object-item p {
  max-width: 70ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.object-item p + p {
  margin-top: 6px;
}

.term-markers {
  margin-bottom: 44px;
}

.marker-list {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.marker-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--green);
  border-radius: var(--radius);
}

.marker-item dt {
  margin-bottom: 4px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.marker-item dd {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-2);
}

.term-pairs {
  margin-bottom: 44px;
}

.pair-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-bottom: 14px;
}

.pair-row:last-child {
  margin-bottom: 0;
}

.pair-col {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.pair-col strong {
  display: block;
  margin-bottom: 4px;
  font-size: 15px;
  color: var(--text);
}

/* 5.5 专题页 specials */
.special-list,
.special-compare,
.watch-order,
.special-tips {
  margin-bottom: 44px;
}

.special-entry {
  display: grid;
  grid-template-columns: minmax(0, 300px) minmax(0, 1fr);
  gap: 22px;
  padding: 22px 0;
  border-top: 1px solid var(--line-soft);
}

.special-entry:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.special-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--panel);
  align-self: start;
}

.special-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.special-figure figcaption {
  padding: 8px 12px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-2);
  background-color: var(--panel-2);
  border-top: 1px solid var(--line-soft);
}

.special-body {
  min-width: 0;
}

.special-body h3 {
  font-size: 20px;
  line-height: 1.4;
  font-weight: 700;
  color: var(--text);
}

.special-body .subtitle-tag {
  margin-bottom: 8px;
}

.condition-list {
  grid-template-columns: minmax(96px, max-content) minmax(0, 1fr);
  margin: 14px 0;
  border-top: 1px solid var(--line-soft);
}

.condition-list dt,
.condition-list dd {
  padding: 8px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 14px;
  line-height: 1.7;
}

.condition-list dt {
  padding-right: 12px;
  color: var(--text-3);
}

.condition-list dd {
  color: var(--text);
}

.order-steps {
  display: grid;
  gap: 12px;
  counter-reset: order;
}

.order-step {
  position: relative;
  padding: 16px 18px 16px 54px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
  counter-increment: order;
}

.order-step::before {
  content: counter(order);
  position: absolute;
  left: 16px;
  top: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: var(--radius-sm);
  background-color: var(--red-soft);
  color: #ff9b9e;
  font-size: 13px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.step-index {
  display: block;
  margin-bottom: 2px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-3);
}

/* 5.6 问答页 faq */
.faq-group {
  margin-bottom: 40px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--panel);
  margin-bottom: 10px;
}

.faq-item:last-child {
  margin-bottom: 0;
}

.faq-item summary {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 52px;
  padding: 14px 46px 14px 18px;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  font-weight: 400;
  color: var(--red);
  line-height: 1;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item summary:hover {
  color: #ffffff;
}

.faq-answer {
  padding: 0 18px 16px;
  border-top: 1px solid var(--line-soft);
  padding-top: 14px;
}

.faq-answer p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-2);
}

.faq-answer p + p {
  margin-top: 10px;
}

.feedback-link {
  margin-top: 8px;
  font-size: 15px;
}

/* 5.7 关于页 about */
.scope-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 16px;
}

.scope-col {
  min-width: 0;
  padding: 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.scope-col-in {
  border-top: 2px solid var(--green);
}

.scope-col-out {
  border-top: 2px solid var(--red);
}

.scope-col h3 {
  margin-bottom: 10px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.scope-col-in .scope-list li::before {
  background-color: var(--green);
}

.scope-col-out .scope-list li::before {
  background-color: var(--red);
}

.scope-note {
  margin-top: 14px;
  font-size: 14px;
  color: var(--text-3);
}

.media-rules {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.media-rule {
  padding: 16px 18px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-2);
}

.media-rule strong {
  color: var(--text);
  font-weight: 600;
}

.feedback-list {
  counter-reset: fb;
  margin-top: 14px;
}

.feedback-note {
  margin-top: 14px;
  font-size: 14px;
  color: var(--text-3);
}

/* 5.8 404 */
.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 64px 20px 80px;
}

.error-inner {
  width: 100%;
  max-width: 640px;
  text-align: left;
}

.error-inner h1 {
  margin: 14px 0 12px;
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1.2;
  font-weight: 700;
  color: var(--text);
}

.error-lead {
  font-size: 16px;
  color: var(--text-2);
}

.error-tips {
  margin: 24px 0;
  padding: 18px 20px;
  background-color: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-path {
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 14px;
  color: var(--text-3);
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* --------------------------------------------------------------------------
   6. responsive —— 960px / 640px 断点
   -------------------------------------------------------------------------- */

@media (max-width: 960px) {
  .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

  .page-layout .page-aside,
  .page-layout .content-aside {
    position: static;
    top: auto;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .hero-copy h1 {
    margin-top: 12px;
  }

  .portal-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .theme-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .steps-grid,
  .check-grid,
  .step-list,
  .step-flow,
  .three-column {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .glossary-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .featured-item,
  .special-entry {
    grid-template-columns: minmax(0, 260px) minmax(0, 1fr);
    gap: 20px;
  }

  /* 移动导航：只收起列表本身 */
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: block;
    background-color: #0c0f14;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.4);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 12px 14px;
  }

  .nav-list.is-open {
    display: flex;
  }

  .nav-list li {
    display: block;
  }

  .nav-list a {
    min-height: 46px;
    padding: 0 12px;
    border-radius: var(--radius-sm);
  }

  .nav-list a.is-current::before {
    top: 10px;
    bottom: 10px;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 16px;
  }

  .header-inner {
    padding: 0 16px;
  }

  .container,
  .page-container,
  .page-layout,
  .hero-inner,
  .portal,
  .featured,
  .compare,
  .theme-band,
  .basics-three,
  .advanced-preview,
  .glossary-preview,
  .ask-first,
  .footer-inner {
    padding-left: 16px;
    padding-right: 16px;
  }

  .inner-main {
    padding: 20px 0 56px;
  }

  .page-title {
    font-size: 28px;
  }

  .hero {
    padding: 26px 0 40px;
  }

  .hero-copy h1 {
    font-size: 28px;
  }

  .portal,
  .featured,
  .compare,
  .theme-band,
  .basics-three,
  .advanced-preview,
  .glossary-preview,
  .ask-first {
    padding-top: 38px;
    padding-bottom: 38px;
  }

  .section-head h2 {
    font-size: 22px;
  }

  .content-section h2,
  .section-block h2,
  .content-block h2,
  .faq-group h2,
  .glossary-quick h2,
  .term-objects h2,
  .term-markers h2,
  .term-pairs h2 {
    font-size: 21px;
  }

  .portal-grid,
  .theme-list,
  .glossary-grid,
  .steps-grid,
  .check-grid,
  .step-list,
  .step-flow,
  .three-column,
  .two-column,
  .advanced-columns,
  .topic-grid,
  .structure-list,
  .term-list,
  .marker-list,
  .pair-row,
  .scope-columns {
    grid-template-columns: minmax(0, 1fr);
  }

  .featured-item,
  .special-entry {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }

  .cond-list,
  .condition-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .cond-list dt,
  .condition-list dt {
    padding-bottom: 0;
    border-bottom: 0;
    font-size: 13px;
  }

  .cond-list dd,
  .condition-list dd {
    padding-top: 2px;
  }

  .form-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .form-item dd.form-tags {
    grid-column: 1;
  }

  .misread-item,
  .mistake-item {
    grid-template-columns: minmax(0, 1fr);
  }

  .misread-wrong,
  .mistake-wrong {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .footer-groups {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .ask-link {
    align-items: flex-start;
    flex-direction: column;
    gap: 2px;
  }

  .summary-box,
  .conclusion-box {
    padding: 18px 16px 18px 20px;
  }

  .faq-item summary {
    padding: 12px 42px 12px 14px;
    font-size: 15px;
  }

  .faq-answer {
    padding: 12px 14px 14px;
  }

  .aside-block {
    padding: 16px;
  }

  .error-main {
    padding: 48px 16px 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}