/* ========== 全局重置 & 基础字体 ========== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

* {
    -webkit-tap-highlight-color: transparent;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #1a202c;
    background-color: #f7fafc;
    overflow-x: hidden;
}

/* 滚动条 */
::-webkit-scrollbar {
    width: 6px;
}
::-webkit-scrollbar-track {
    background: #f1f1f1;
}
::-webkit-scrollbar-thumb {
    background: #cbd5e0;
    border-radius: 10px;
}

/* 导航栏滚动效果 */
header.nav-scrolled {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    border-bottom: 1px solid rgba(226, 232, 240, 0.6);
}

/* 移动端菜单动画 */
.mobile-menu {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.2, 0.9, 0.4, 1.1), opacity 0.3s ease;
}
.mobile-menu.open {
    max-height: 500px;
    opacity: 1;
}

/* 滚动显示动画 */
.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s cubic-bezier(0.2, 0.9, 0.4, 1.1), transform 0.7s cubic-bezier(0.2, 0.9, 0.4, 1.1);
}
.scroll-reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

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

/* 课程卡片悬停 */
.course-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.course-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 25px -12px rgba(0, 0, 0, 0.15);
}

/* 移动端浮动卡片调整 */
@media (max-width: 768px) {
    .hero-floating-card-1 {
        bottom: -12px !important;
        left: 8px !important;
        padding: 0.75rem 1rem !important;
    }
    .hero-floating-card-2 {
        top: -12px !important;
        right: 8px !important;
        padding: 0.75rem 1rem !important;
    }
    .hero-floating-card-1 p, .hero-floating-card-2 p {
        font-size: 0.875rem !important;
    }
    .hero-floating-card-1 .text-3xl, .hero-floating-card-2 .text-3xl {
        font-size: 1.5rem !important;
    }
    section {
        scroll-margin-top: 70px;
    }
    .container {
        padding-left: 1rem;
        padding-right: 1rem;
    }
}

@media (min-width: 769px) {
    section {
        scroll-margin-top: 80px;
    }
}

@media (hover: hover) {
    .hover-lift:hover {
        transform: translateY(-3px);
    }
}

/* 课程标签组 */
.course-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}
.course-tags span {
    font-size: 0.7rem;
    padding: 0.25rem 0.7rem;
    background-color: #f8fafc;
    border-radius: 999px;
    color: #2d3748;
}

/* 图片遮罩 */
.img-overlay {
    background: linear-gradient(to top, rgba(0,0,0,0.4), transparent);
}

/* 特定图片尺寸 */
.logo-img,
.footer-logo {
    width: 28px;
    height: 24px;
}
.hero-main-img {
    width: 557px;
}
.hero-image-wrapper .c16037 {
    transition-delay: 0.1s;
}

/* 页脚描述文字无背景框 */
.footer-desc {
    color: rgb(148, 163, 184);
    font-size: medium;
    background-color: transparent;
}

/* 确保原有部分类名兼容 */
.c207873,
.c210307 {
    width: 28px;
    height: 24px;
}
.c208367 {
    width: 557px;
}
.c16037 {
    transition-delay: 0.1s;
}