/* 
=====================================================================
* 文件名: Style-Introduction.css
* 版本: V1.0
* 创建日期: 2025-06-01
* 最后修改: 2025-07-05
* 
* 功能简介:
* - "Yang Lab 杨旭三个人简介" 页面的主样式表
* - 实现核心的卡片式布局和悬停展开动画效果
* - 定义了页面背景、字体、颜色等
* - 包含"返回主页"按钮的样式
* - 包含针对移动设备的响应式设计，在小屏幕上禁用复杂动画
=====================================================================
*/

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@100;200;300;400;500;600;700&display=swap');

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: #151515;
}

.card {
    position: relative;
    width: 350px;
    height: 350px;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: 0.5s;

    border-radius: 20px;
    transition-delay: 0.5s;
}

.card:hover {
    width: 1000px;
    height: 600px;
    transition-delay: 0.5s;
}

.card .circle {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.card .circle::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    border-radius: 50%;

    width: 350px;
    height: 350px;
    background: #191919;
    border: 8px solid var(--clr);

    filter: drop-shadow(0 0 10px var(--clr)) drop-shadow(0 0 60px var(--clr));
    transition: 0.5s, background0.5s;
    transition-delay: 0.75s, 1s;
}

.card:hover .circle::before {
    width: 100%;
    height: 100%;
    border-radius: 20px;
    background: var(--clr);
    transition-delay: 0.5s;

}

.card .circle .logo {
    position: relative;
    width: 250px;
    transition: 0.5s;
    transition-delay: 0.5s;

}

.card:hover .circle .logo {
    transform: scale(0);
    transition-delay: 0s;
}

.card .product_img {
    position: absolute;
    top: 40%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0) rotate(315deg);
    height: 800px;
    transition: 0.5s ease-in-out;
}

.card:hover .product_img {
    transition-delay: 0.75s;
    top: 50%;
    left: 82%;
    height: 500px;
    transform: translate(-50%, -50%) scale(1) rotate(3deg);
}

.card .content {
    position: absolute;
    width: 65%;
    left: 20%;
    padding: 20px 20px 20px 40px;
    opacity: 0;
    transition: 0.5s;
    visibility: hidden;
}

.card:hover .content {
    transition-delay: 0.75s;
    opacity: 1;
    visibility: visible;
    left: 20px;
}

.card .content h2 {
    color: #fff;
    text-transform: uppercase;
    font-size: 2.5em;
    line-height: 1em;
}

.card .content p {
    color: #fff;
}

.card .content a {
    position: relative;
    color: #111;
    background: #fff;
    padding: 10px 20px;
    border-radius: 10px;
    display: inline-block;
    text-decoration: none;
    font-weight: 600;
    margin-top: 10px;
}

.back-to-home {
    position: absolute;
    top: 20px;
    left: 20px;
    color: #fff;
    text-decoration: none;
    background: rgba(0, 0, 0, 0.3);
    padding: 10px 15px;
    border-radius: 20px;
    font-size: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    z-index: 10;
    transition: background 0.3s;
}

.back-to-home:hover {
    background: rgba(0, 0, 0, 0.6);
}

/* =====================================================================
 * 移动端响应式设计 (Mobile Responsive Design)
 * ===================================================================== */
@media (max-width: 900px) {

    /* 禁用桌面端的悬停展开效果 */
    .card:hover {
        width: 90%;
        max-width: 450px;
        height: auto;
        min-height: 80vh;
        transition-delay: 0s;
    }

    .card {
        width: 90%;
        max-width: 450px;
        height: auto;
        min-height: 80vh;
        padding: 20px;
        flex-direction: column;
        align-items: center;
        transition-delay: 0s !important;
        transition: none;
    }

    .card .circle,
    .card:hover .circle {
        position: relative;
        width: 150px;
        height: 150px;
        margin-bottom: 20px;
    }

    .card .circle::before,
    .card:hover .circle::before {
        width: 100%;
        height: 100%;
        border-radius: 50%;
        background: var(--clr);
        transition-delay: 0s !important;
        transition: none;
    }

    .card .circle .logo,
    .card:hover .circle .logo {
        display: none;
        /* 在移动端直接隐藏logo，让位于内容 */
    }

    .card .content,
    .card:hover .content {
        position: relative;
        width: 100%;
        left: 0;
        padding: 0;
        opacity: 1;
        visibility: visible;
        text-align: center;
        transition-delay: 0s !important;
        transition: none;
    }

    .card .content h2 {
        font-size: 1.8em;
    }

    .card .content p {
        font-size: 1em;
    }

    .card .product_img,
    .card:hover .product_img {
        display: none;
        /* 在移动端隐藏教授图片，让内容优先 */
    }

    .back-to-home {
        top: 15px;
        left: 15px;
        padding: 8px 12px;
        font-size: 14px;
    }
}