*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
:root {
  --primary: #E03A3E;
  --secondary: #1E88E5;
  --accent: #FF6F00;
  --bg-dark: #1A1A1A;
  --bg-light: #F5F5F5;
  --text-primary: #121212;
  --text-secondary: #757575;
  --border: #E0E0E0;
  --shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
  --font-heading: 'Noto Sans SC', 'Helvetica Neue', sans-serif;
  --font-body: 'Noto Sans SC', 'Helvetica Neue', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --content-width: 1280px;
  --grid-gap: 24px;
  --header-height: 80px;
  --border-thick: 4px;
  --transition: 0.2s ease;
}
html {
  scroll-behavior: smooth;
}
body {
  font-family: var(--font-body);
  line-height: 1.6;
  background: var(--bg-light);
  color: var(--text-primary);
  -webkit-text-size-adjust: 100%;
}
a {
  color: inherit;
  text-decoration: none;
}
ul,
ol {
  list-style: none;
}
img {
  max-width: 100%;
  display: block;
}
button {
  font: inherit;
  cursor: pointer;
  border: none;
  background: none;
}
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  background: var(--primary);
  color: #fff;
  padding: 8px 16px;
  z-index: 1000;
  font-weight: 700;
  clip: rect(1px, 1px, 1px, 1px);
  transition: top var(--transition);
}
.skip-link:focus {
  top: 0;
  clip: auto;
}
/* 容器 */
.container {
  max-width: var(--content-width);
  margin: 0 auto;
  padding-left: 20px;
  padding-right: 20px;
}
/* 头部 */
.header {
  background: var(--bg-dark);
  color: #fff;
  border-bottom: var(--border-thick) solid var(--primary);
  position: relative;
  z-index: 100;
}
.header__inner {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}
.header__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.header__logo {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.6rem;
  color: var(--primary);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}
.header__tagline {
  font-size: 0.75rem;
  color: var(--secondary);
  margin-top: -2px;
  letter-spacing: 0.1em;
}
.nav__list {
  display: flex;
  gap: 12px;
}
.nav__link {
  display: inline-block;
  padding: 8px 12px;
  font-size: 0.9rem;
  font-weight: 600;
  border: 2px solid transparent;
  color: #fff;
  transition: color var(--transition), border-color var(--transition);
  position: relative;
}
.nav__link:hover,
.nav__link:focus-visible {
  color: var(--primary);
  border-bottom-color: var(--primary);
}
.nav__link[aria-current="page"] {
  color: var(--primary);
  border-bottom: 2px solid var(--primary);
}
.header__actions {
  display: flex;
  align-items: center;
  gap: 12px;
}
.nav__favorites {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: #fff;
  font-size: 1.1rem;
  padding: 6px 10px;
  border-radius: 4px;
  transition: background var(--transition);
}
.nav__favorites:hover {
  background: rgba(255, 255, 255, 0.1);
}
.nav__favorites-icon {
  color: var(--accent);
}
.nav__favorites-badge {
  background: var(--primary);
  color: #fff;
  font-size: 0.7rem;
  padding: 1px 6px;
  border-radius: 10px;
  font-weight: 700;
}
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 28px;
  height: 28px;
  padding: 4px;
}
.nav__toggle-line {
  display: block;
  width: 100%;
  height: 3px;
  background: #fff;
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}
/* 移动导航 */
@media (max-width: 768px) {
  .header__inner {
    flex-wrap: wrap;
    height: auto;
    padding: 12px 20px;
  }
  .header__brand {
    order: 1;
  }
  .header__actions {
    order: 2;
  }
  .nav {
    order: 3;
    width: 100%;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, opacity 0.3s ease;
    opacity: 0;
  }
  .nav[data-open] {
    max-height: 500px;
    opacity: 1;
  }
  .nav__list {
    flex-direction: column;
    gap: 4px;
    padding: 12px 0;
  }
  .nav__link {
    display: block;
    padding: 12px 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }
  .nav__toggle {
    display: flex;
  }
  .nav__toggle[aria-expanded="true"] .nav__toggle-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .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: rotate(-45deg) translate(5px, -5px);
  }
}
/* 页脚 */
.footer {
  background: var(--bg-dark);
  color: #ccc;
  padding: 48px 20px 24px;
  border-top: var(--border-thick) solid var(--primary);
}
.footer__inner {
  max-width: var(--content-width);
  margin: 0 auto;
}
.footer__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  margin-bottom: 40px;
}
.footer__column h3 {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  color: var(--primary);
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}
.footer__links li {
  margin-bottom: 8px;
}
.footer__links a {
  color: #aaa;
  font-size: 0.9rem;
  transition: color var(--transition);
}
.footer__links a:hover {
  color: #fff;
}
.footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.8rem;
  color: #999;
}
.footer__trust {
  line-height: 1.5;
}
.footer__contact a {
  color: var(--secondary);
}
.footer__contact a:hover {
  text-decoration: underline;
}
.footer__icp {
  color: #777;
}
@media (max-width: 992px) {
  .footer__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
}
@media (max-width: 576px) {
  .footer__grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
}
/* 通用组件 */
.btn {
  display: inline-block;
  padding: 10px 24px;
  font-weight: 700;
  font-size: 0.9rem;
  border: 2px solid var(--primary);
  background: transparent;
  color: var(--primary);
  transition: background var(--transition), color var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.btn:hover,
.btn:focus-visible {
  background: var(--primary);
  color: #fff;
}
.btn[data-btn-style="secondary"] {
  border-color: var(--secondary);
  color: var(--secondary);
}
.btn[data-btn-style="secondary"]:hover,
.btn[data-btn-style="secondary"]:focus-visible {
  background: var(--secondary);
  color: #fff;
}
.card {
  background: #fff;
  border: var(--border-thick) solid var(--border);
  box-shadow: var(--shadow);
  padding: 24px;
  transition: transform var(--transition), box-shadow var(--transition);
}
.card[data-card-hover]:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 28px rgba(0,0,0,0.3);
}
.section {
  padding: 60px 20px;
}
.section__title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 2rem;
  color: var(--text-primary);
  letter-spacing: 0.03em;
  margin-bottom: 12px;
  position: relative;
}
.section__title::after {
  content: '';
  display: block;
  width: 60px;
  height: var(--border-thick);
  background: var(--primary);
  margin-top: 8px;
}
.section__desc {
  font-size: 1rem;
  color: var(--text-secondary);
  max-width: 680px;
}
.mono {
  font-family: var(--font-mono);
}
.brand-accent {
  color: var(--primary);
}
/* focus-visible与无动画偏好 */
:focus-visible {
  outline: 2px dashed var(--primary);
  outline-offset: 2px;
}
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  .card[data-card-hover]:hover {
    transform: none !important;
  }
  .nav[data-open] {
    max-height: none !important;
    opacity: 1 !important;
  }
  html {
    scroll-behavior: auto;
  }
}
/* 图片容器基础 */
.picture-container {
  position: relative;
  overflow: hidden;
  background: var(--border);
  aspect-ratio: 16 / 9;
}
.picture-container > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
/* 响应式微调 */
@media (max-width: 576px) {
  .section__title {
    font-size: 1.5rem;
  }
  .section {
    padding: 40px 16px;
  }
}