/* ============ 变量与基础 ============ */
:root {
  --kp-primary: #8BC34A;
  --kp-primary-dark: #558B2F;
  --kp-accent: #FF9800;
  --kp-blue: #1E88E5;
  --kp-bg-light: #F5F8EE;
  --kp-bg-dark: #0B1A2E;
  --kp-text: #1D1D1D;
  --kp-white: #FFFFFF;
  --kp-rule: #C0D890;

  --kp-font-heading: "Noto Sans SC", "Source Han Sans SC", sans-serif;
  --kp-font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --kp-font-mono: "Roboto Mono", "SFMono-Regular", "Consolas", monospace;
  --kp-body-size: 16px;

  --kp-container: 1260px;
  --kp-container-narrow: 880px;
  --kp-masthead-h: 40px;
  --kp-header-h: 56px;
  --kp-space-1: 0.25rem;
  --kp-space-2: 0.5rem;
  --kp-space-3: 1rem;
  --kp-space-4: 1.5rem;
  --kp-space-5: 2.5rem;
  --kp-space-6: 4rem;
  --kp-bp-mobile: 600px;
  --kp-bp-nav: 900px;
  --kp-bp-tablet: 1024px;
  --kp-radius: 8px;
  --kp-shadow: 0 6px 20px rgba(11, 26, 46, 0.09);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  font-family: var(--kp-font-body);
  font-size: var(--kp-body-size);
  line-height: 1.6;
  color: var(--kp-text);
  background: var(--kp-bg-light);
  -webkit-font-smoothing: antialiased;
}

#main-content {
  display: block;
  scroll-margin-top: calc(var(--kp-masthead-h) + var(--kp-header-h) + 12px);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--kp-font-heading);
  line-height: 1.2;
  font-weight: 700;
  color: var(--kp-text);
}

p {
  margin-bottom: 0.75rem;
}

ul, ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  background: none;
  border: none;
}

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

::selection {
  background: var(--kp-primary);
  color: var(--kp-bg-dark);
}

:focus-visible {
  outline: 3px solid var(--kp-accent);
  outline-offset: 2px;
}

/* ============ 跳过链接与进度条 ============ */
.skip-link {
  position: fixed;
  top: -120px;
  left: 1rem;
  z-index: 1200;
  background: var(--kp-bg-dark);
  color: var(--kp-white);
  font-weight: 700;
  padding: 0.7rem 1.2rem;
  border-radius: 0 0 6px 6px;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 4px;
  background: linear-gradient(90deg, var(--kp-primary), var(--kp-accent));
  z-index: 1100;
  pointer-events: none;
}

/* ============ 页头 ============ */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  z-index: 900;
  box-shadow: 0 3px 14px rgba(11, 26, 46, 0.07);
}

.header-masthead {
  background: var(--kp-primary);
  color: var(--kp-bg-dark);
  font-family: var(--kp-font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  line-height: 1.4;
}

.header-masthead-inner {
  max-width: var(--kp-container);
  margin: 0 auto;
  padding: 0.45rem 1.25rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  min-height: var(--kp-masthead-h);
}

.masthead-edition,
.masthead-tools {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  overflow: hidden;
  white-space: nowrap;
}

.masthead-kicker {
  font-weight: 700;
  color: var(--kp-bg-dark);
}

.masthead-vol {
  font-weight: 400;
  color: var(--kp-bg-dark);
  opacity: 0.65;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
}

.masthead-link {
  font-weight: 700;
  color: var(--kp-bg-dark);
  padding: 0.15rem 0.35rem;
  border-radius: 3px;
  text-decoration: underline;
  text-decoration-color: currentColor;
  text-underline-offset: 4px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.masthead-link:hover {
  background: var(--kp-bg-dark);
  color: var(--kp-primary);
  text-decoration-color: transparent;
}

.header-navbar {
  background: var(--kp-white);
  border-bottom: 3px solid var(--kp-bg-dark);
}

.header-navbar-inner {
  max-width: var(--kp-container);
  margin: 0 auto;
  padding: 0.6rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  min-height: var(--kp-header-h);
}

/* 品牌组合 */
.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  flex-shrink: 0;
}

.brand-lockup-logo {
  position: relative;
  display: inline-block;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, var(--kp-primary), var(--kp-primary-dark) 72%);
  box-shadow: inset 0 0 0 2px var(--kp-primary-dark);
  flex-shrink: 0;
}

.brand-lockup-logo::after {
  content: "";
  position: absolute;
  inset: -5px;
  border: 2px dashed var(--kp-accent);
  border-radius: 50%;
  animation: kp-spin 14s linear infinite;
}

.brand-lockup-name {
  font-family: var(--kp-font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--kp-bg-dark);
  letter-spacing: 0.02em;
  line-height: 1;
}

.brand-lockup-name strong {
  font-weight: 900;
  color: var(--kp-primary-dark);
}

@keyframes kp-spin {
  to {
    transform: rotate(360deg);
  }
}

/* 主导航 */
.site-nav {
  display: block;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.2rem;
}

.nav-item {
  margin: 0;
}

.nav-link {
  display: inline-block;
  padding: 0.5rem 0.7rem;
  font-weight: 700;
  font-size: 0.92rem;
  color: var(--kp-text);
  border-radius: 4px;
  position: relative;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav-link:hover {
  color: var(--kp-primary-dark);
  background: var(--kp-bg-light);
}

.nav-link[aria-current="page"] {
  color: var(--kp-bg-dark);
}

.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0.7rem;
  right: 0.7rem;
  bottom: 0;
  height: 3px;
  background: var(--kp-accent);
}

.nav-item-featured .nav-link {
  background: var(--kp-accent);
  color: var(--kp-bg-dark);
  border-radius: 999px;
  padding: 0.42rem 0.85rem 0.42rem 1.1rem;
  font-weight: 700;
  box-shadow: 0 2px 0 rgba(11, 26, 46, 0.15);
  transition: background-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.nav-item-featured .nav-link:hover {
  background: #e68600;
  color: var(--kp-white);
  transform: translateY(-1px);
}

.nav-item-featured .nav-link::after {
  display: none;
}

.nav-feature-tag {
  display: inline-block;
  margin-left: 0.45rem;
  padding: 0.18rem 0.4rem;
  font-family: var(--kp-font-mono);
  font-size: 0.58rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  background: var(--kp-blue);
  color: var(--kp-white);
  border-radius: 3px;
  vertical-align: middle;
  line-height: 1.3;
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 9px;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  border-radius: 4px;
  background: var(--kp-bg-light);
  border: 1px solid var(--kp-rule);
  flex-shrink: 0;
}

.nav-toggle-line {
  display: block;
  width: 100%;
  height: 3px;
  background: var(--kp-bg-dark);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* ============ 页脚 ============ */
.site-footer {
  background: var(--kp-bg-dark);
  color: var(--kp-white);
  font-size: 0.9rem;
}

.footer-main {
  max-width: var(--kp-container);
  margin: 0 auto;
  padding: 3.5rem 1.25rem 2.5rem;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 2.5rem;
}

.footer-brand {
  max-width: 42ch;
}

.footer-logo {
  display: inline-block;
  font-family: var(--kp-font-heading);
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--kp-primary);
  margin-bottom: 0.8rem;
  letter-spacing: 0.02em;
}

.footer-logo:hover {
  color: var(--kp-accent);
}

.footer-slogan {
  color: rgba(255, 255, 255, 0.68);
  font-size: 0.86rem;
  line-height: 1.7;
}

.footer-column {
  min-width: 0;
}

.footer-heading {
  font-family: var(--kp-font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--kp-primary);
  margin-bottom: 0.8rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid rgba(139, 195, 74, 0.35);
}

.footer-links li {
  margin-bottom: 0.35rem;
}

.footer-links a,
.footer-contact-list a {
  color: rgba(255, 255, 255, 0.72);
  padding: 0.15rem 0;
  display: inline-block;
  transition: color 0.2s ease, transform 0.2s ease;
}

.footer-links a:hover {
  color: var(--kp-accent);
  transform: translateX(3px);
}

.footer-contact-list li {
  margin-bottom: 0.6rem;
  color: rgba(255, 255, 255, 0.62);
  line-height: 1.55;
  word-break: break-word;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-bottom-inner {
  max-width: var(--kp-container);
  margin: 0 auto;
  padding: 1rem 1.25rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.6rem;
  align-items: center;
  font-family: var(--kp-font-mono);
  font-size: 0.74rem;
  color: rgba(255, 255, 255, 0.55);
}

.footer-copyright,
.footer-icp {
  white-space: nowrap;
}

.footer-trust {
  flex-basis: 100%;
  opacity: 0.75;
  line-height: 1.6;
}

/* ============ 内容容器 ============ */
.container {
  width: 100%;
  max-width: var(--kp-container);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.container-narrow {
  width: 100%;
  max-width: var(--kp-container-narrow);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: var(--kp-space-6) 0;
}

.section-tight {
  padding: var(--kp-space-4) 0;
}

/* ============ 通用排版组件 ============ */
.eyebrow {
  display: inline-block;
  font-family: var(--kp-font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--kp-primary-dark);
  margin-bottom: 0.6rem;
}

.section-title {
  font-family: var(--kp-font-heading);
  font-size: clamp(1.6rem, 3.6vw, 2.4rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.01em;
  color: var(--kp-text);
}

.section-lead {
  font-size: 1rem;
  color: #636363;
  max-width: 62ch;
  line-height: 1.75;
  margin-top: 0.75rem;
}

/* ============ 按钮 ============ */
.btn {
  display: inline-block;
  padding: 0.7rem 1.5rem;
  font-weight: 700;
  font-size: 0.92rem;
  border-radius: 6px;
  border: 2px solid transparent;
  text-align: center;
  transition: background-color 0.2s ease, color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: var(--kp-primary);
  color: var(--kp-bg-dark);
  border-color: var(--kp-primary-dark);
  box-shadow: 0 3px 0 var(--kp-primary-dark);
}

.btn-primary:hover {
  background: var(--kp-primary-dark);
  color: var(--kp-white);
  box-shadow: 0 2px 0 var(--kp-bg-dark);
}

.btn-accent {
  background: var(--kp-accent);
  color: var(--kp-bg-dark);
  border-color: #cc7a00;
  box-shadow: 0 3px 0 #cc7a00;
}

.btn-accent:hover {
  background: #e68600;
  color: var(--kp-white);
  box-shadow: 0 2px 0 var(--kp-bg-dark);
}

.btn-outline {
  border: 2px solid var(--kp-text);
  color: var(--kp-text);
  background: transparent;
}

.btn-outline:hover {
  background: var(--kp-text);
  color: var(--kp-white);
}

/* ============ 卡片与网格 ============ */
.card {
  background: var(--kp-white);
  border: 1px solid var(--kp-rule);
  border-radius: var(--kp-radius);
  padding: 1.4rem;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--kp-shadow);
}

.grid {
  display: grid;
  gap: 1.5rem;
}

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

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

/* ============ 标签 ============ */
.tag {
  display: inline-block;
  font-family: var(--kp-font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 0.24rem 0.55rem;
  background: var(--kp-primary);
  color: var(--kp-bg-dark);
  border-radius: 3px;
  line-height: 1.3;
}

.tag-accent {
  background: var(--kp-accent);
  color: var(--kp-bg-dark);
}

.tag-blue {
  background: var(--kp-blue);
  color: var(--kp-white);
}

.tag-outline {
  background: transparent;
  border: 1px solid var(--kp-primary-dark);
  color: var(--kp-primary-dark);
}

/* ============ 媒体占位容器 ============ */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  background: linear-gradient(135deg, var(--kp-bg-light) 0%, var(--kp-primary) 100%);
  border: 1px solid var(--kp-rule);
  border-radius: var(--kp-radius);
}

.media-frame::before {
  content: "";
  display: block;
}

.media-frame > * {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-16-9::before {
  padding-top: 56.25%;
}

.media-4-3::before {
  padding-top: 75%;
}

.media-3-2::before {
  padding-top: 66.666%;
}

.media-1-1::before {
  padding-top: 100%;
}

/* ============ 深色面板与印刷线 ============ */
.panel-dark {
  position: relative;
  background: var(--kp-bg-dark);
  color: var(--kp-white);
  padding: 2rem;
  border-radius: var(--kp-radius);
  overflow: hidden;
}

.panel-dark::before {
  content: "";
  position: absolute;
  top: -30px;
  right: -30px;
  width: 110px;
  height: 110px;
  border-radius: 50%;
  background: var(--kp-primary);
  opacity: 0.18;
}

.panel-dark > * {
  position: relative;
  z-index: 1;
}

.print-rule {
  width: 100%;
  height: 1px;
  background: repeating-linear-gradient(
    90deg,
    var(--kp-text) 0 6px,
    transparent 6px 12px
  );
  margin: 1.5rem 0;
}

/* ============ 面包屑 ============ */
.breadcrumbs {
  padding: 0.9rem 0 0.3rem;
  font-family: var(--kp-font-mono);
  font-size: 0.76rem;
}

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.breadcrumbs li {
  color: var(--kp-text);
  padding: 0.15rem 0.25rem;
}

.breadcrumbs a {
  color: var(--kp-blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.breadcrumbs a:hover {
  color: var(--kp-primary-dark);
}

/* ============ 返回顶部 ============ */
.top-button {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  width: 2.8rem;
  height: 2.8rem;
  border-radius: 50%;
  background: var(--kp-primary);
  color: var(--kp-bg-dark);
  font-size: 1.4rem;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.25s ease, transform 0.25s ease, background-color 0.2s ease;
  box-shadow: 0 4px 14px rgba(11, 26, 46, 0.2);
  z-index: 500;
}

.top-button[data-visible] {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.top-button:hover {
  background: var(--kp-accent);
  color: var(--kp-bg-dark);
}

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-main {
    grid-template-columns: 1fr 1fr;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .header-navbar-inner {
    flex-wrap: wrap;
    padding: 0.5rem 1rem;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    flex-basis: 100%;
    display: none;
  }

  .site-nav[data-open] {
    display: block;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.3rem;
    padding: 0.6rem 0 0.3rem;
    border-top: 1px solid var(--kp-rule);
  }

  .nav-item-featured .nav-link::after {
    display: none;
  }

  .nav-link {
    display: block;
    padding: 0.8rem 0.6rem;
    border-left: 3px solid transparent;
  }

  .nav-link:hover {
    background: var(--kp-bg-light);
  }

  .nav-link[aria-current="page"] {
    border-left-color: var(--kp-accent);
  }

  .nav-link[aria-current="page"]::after {
    display: none;
  }

  .nav-item-featured .nav-link {
    text-align: center;
    border-radius: 999px;
  }

  .masthead-vol {
    display: none;
  }

  .footer-main {
    gap: 2rem;
  }
}

@media (max-width: 600px) {
  .header-masthead-inner {
    padding: 0.4rem 0.9rem;
  }

  .masthead-kicker {
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 45vw;
  }

  .header-navbar-inner {
    padding: 0.5rem 0.9rem;
  }

  .footer-main {
    grid-template-columns: 1fr;
    padding-top: 2.5rem;
  }

  .footer-brand {
    grid-column: auto;
  }

  .footer-bottom-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .btn {
    width: 100%;
  }
}

/* ============ 减少动态效果 ============ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}