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

:root {
    --primary-black: #1a1a1a;
    --text-gray: #4a4a4a;
    --bg-light: #fafafa;
}

/* 基础排版 */
body {
    font-family: 'Helvetica Neue', 'Montserrat', 'PingFang SC', 'Noto Sans SC', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: var(--primary-black);
    background-color: #ffffff;
    line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 400;
    letter-spacing: 0.05em;
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background-color: #d1d5db;
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background-color: #9ca3af;
}

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

@keyframes slideUp {
    from { 
        opacity: 0; 
        transform: translateY(20px); 
    }
    to { 
        opacity: 1; 
        transform: translateY(0); 
    }
}

/* 实用动画类 */
.animate-fade-in {
    animation: fadeIn 1s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.animate-slide-up {
    opacity: 0;
    animation: slideUp 0.8s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }

/* 图片交互组件 */
.img-zoom-container {
    overflow: hidden;
    position: relative;
    display: block;
}

.img-zoom-container img {
    transition: transform 0.7s cubic-bezier(0.25, 0.46, 0.45, 0.94), opacity 0.3s ease;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.img-zoom-container:hover img {
    transform: scale(1.03);
}

/* 导航交互 */
.nav-link {
    position: relative;
    display: inline-block;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: -2px;
    left: 0;
    background-color: currentColor;
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* 极简网格布局辅助 */
.aspect-ratio-box {
    position: relative;
    width: 100%;
    padding-bottom: 133.33%; /* 3:4 比例 */
    background-color: var(--bg-light);
}

.aspect-ratio-box img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 动态槽位标识 (开发辅助) */
.dynamic-slot {
    display: contents;
}

/* 移动端菜单过渡 */
#mobile-menu {
    transition: all 0.3s ease-in-out;
    overflow: hidden;
}