@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500&family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

/* 全局基础设置 */
:root {
  --color-text-main: #1a1a1a;
  --color-text-muted: #666666;
  --transition-smooth: cubic-bezier(0.22, 1, 0.36, 1);
}

body {
  font-family: 'Inter', 'Noto Sans SC', sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: #ffffff;
  color: var(--color-text-main);
  overflow-x: hidden;
}

/* 极简滚动条 */
::-webkit-scrollbar {
  width: 4px;
  height: 4px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: #e5e5e5;
  border-radius: 2px;
}
::-webkit-scrollbar-thumb:hover {
  background: #a3a3a3;
}

::selection {
  background-color: #000;
  color: #fff;
}

/* 核心动画关键帧 */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUpFade {
  from { opacity: 0; transform: translateY(40px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes kenBurns {
  from { transform: scale(1); }
  to { transform: scale(1.08); }
}

/* 实用动画类 - 配合JS观察器使用 */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 1s var(--transition-smooth), transform 1s var(--transition-smooth);
}

.animate-on-scroll.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.animate-fade-in {
  animation: fadeIn 1.5s var(--transition-smooth) forwards;
}

.animate-slide-up {
  opacity: 0;
  animation: slideUpFade 1.2s var(--transition-smooth) forwards;
}

.delay-200 { animation-delay: 0.2s; }
.delay-400 { animation-delay: 0.4s; }
.delay-600 { animation-delay: 0.6s; }

/* 交互微效 */
.hover-zoom-img {
  transition: transform 0.8s var(--transition-smooth), filter 0.5s ease;
  will-change: transform;
}
.group:hover .hover-zoom-img {
  transform: scale(1.05);
}

.link-underline {
  position: relative;
}
.link-underline::after {
  content: '';
  position: absolute;
  width: 0;
  height: 1px;
  bottom: -2px;
  left: 0;
  background-color: currentColor;
  transition: width 0.4s var(--transition-smooth);
}
.link-underline:hover::after {
  width: 100%;
}

/* 隐藏滚动条但保留功能 */
.no-scrollbar::-webkit-scrollbar {
  display: none;
}
.no-scrollbar {
  -ms-overflow-style: none;
  scrollbar-width: none;
}

/* 视觉排版优化 */
.tracking-fashion {
  letter-spacing: 0.2em;
}
.leading-relaxed-fashion {
  line-height: 1.8;
}