/* ============================= */
/* Global Borders */
/* ============================= */

.top-border, .bottom-border {
    width: 100%;
    height: 35px;
    background: #000;
    position: fixed;
    left: 0;
    z-index: 50;
}

.top-border {
    top: 0;
}

.bottom-border {
    bottom: 0;

    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
}


/* 文字样式 */
.footer-email,
.footer-copy {
    color: #ffffff;
    font-size: 12px;
    letter-spacing: 0.5px;
    white-space: nowrap;
}

/* 版权弱化一点 */
.footer-copy {
    opacity: 0.7;
}

/* ============================= */
/* Back Button */
/* ============================= */
/* 修改 style.css 中的 .back-btn 这一项 */
.back-btn {
    text-decoration: none; /* 去掉下划线 */
    color: white;          /* 设置文字颜色为白色 */
    
    /* 以下是你原有的其他样式，请保持不变或根据需要调整 */
    position: fixed;
    top: 55px;
    left: 25px;
    z-index: 100;
    font-size: 16px;
    /* 如果有 border，也可以设为白色 */
    border: 1px solid white; 
    padding: 8px 15px;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.1); /* 可选：增加一点半透明背景使其更清晰 */
    transition: 0.3s;
}

/* 悬停效果：建议悬停时稍微改变透明度或背景色，增加交互感 */
.back-btn:hover {
    background: white;
    color: black; /* 悬停时文字变黑，形成反差 */
}

/* ============================= */
/* Semester Buttons */
/* ============================= */
.semester-buttons {
    position: fixed;
    top: 60px;
    right: 40px;
    display: flex;
    gap: 10px;
    z-index: 200;
}
.semester-wrapper {
    position: relative;
}

.sem-btn {
    padding: 8px 16px;
    border-radius: 12px;
    background: white;
    border: 2px solid #D9D9D9;
    cursor: pointer;
    font-size: 14px;
}

.sem-menu {
    
    position: absolute;
    top: calc(100% + 10px); /* 正下方 + 间距 */
    left: 0;

    background: white;
    padding: 10px;
    border-radius: 12px;
    border: 2px solid #D9D9D9;

    display: flex;
    flex-direction: column;
    gap: 10px;

    z-index: 300;
}

.hidden { display: none; }

.menu-item {
    padding: 8px 14px;
    background: #f3f3f3;
    border-radius: 10px;
    text-decoration: none;
    color: black;
}

/* ============================= */
/* HOME PAGE */
/* ============================= */
.home-page {
    background: #D2CCCC;
    min-height: 100vh;
}

/* Hero */
.hero {
    width: 100%;
    height: 380px;
    background: url("bg1.jpg") center/cover no-repeat;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    animation: fadeIn 1.5s ease-out forwards;
}

.hero-logo {
    width: 360px;
    opacity: 0;
    animation: fadeIn 1.6s ease forwards 0.4s;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(25px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Project Page */
.project-page {
    background: #A7ADB0;
    height: 100vh;
    overflow: hidden;
}
.project-container {
    display: flex;
    justify-content: space-between; /* 横向分布 */
    gap: 20px; /* 方块间距 */
    margin: 60px auto;
    max-width: 1000px;
}

.proj {
    flex: 1;
    height: 200px;
    border: 2px solid #000;
    cursor: pointer;
    transition: transform 0.3s ease, background-color 0.3s ease;
}

.proj:hover {
    transform: translateY(-5px);
    background-color: #f5f5f5;
}

/* Title */
.project-title {
    text-align: center;
    margin-top: 80px;
    font-size: 48px;
    color: white;
}
.project-container {
    width: 90%;
    max-width: 1200px;
    margin: 80px auto;

    display: flex;
    gap: 30px;
}

.proj {
    flex: 1;
    height: 260px;

    border-radius: 25px;
    border: 2px solid white;
    overflow: hidden;

    background-size: cover;
    background-position: center;

    display: flex;
    align-items: flex-end;
    padding: 20px;

    color: white;
    text-decoration: none;
    font-size: 18px;
    font-weight: 500;

    transition: 0.45s ease;
}

.proj:hover {
    transform: translateY(-12px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.25);
}

/* Hover directional slide effect */
.box1:hover { transform: translate(-12px, -12px); }
.box2:hover { transform: translate(12px, -12px); }
.box3:hover { transform: translate(-12px, 12px); }
.box4:hover { transform: translate(12px, 12px); }
.box1 { background-image: url("P1.JPG"); }
.box2 { background-image: url("P2.jpeg"); }
.box3 { background-image: url("P3.jpg"); }
.box4 { background-image: url("P4.jpg"); }


/* Active card (context mode) */
.proj.active {
    position: absolute;
    width: 65%;
    height: 65%;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%) scale(1.05) !important;
    z-index: 10;
    background: white;
    border-radius: 28px;
    box-shadow: 0 0 50px rgba(0,0,0,0.25);
}

/* Background dim when a card is active */
.project-container.clicked .proj:not(.active) {
    opacity: 0.15;
    pointer-events: none;
}

.project-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 30px;
    margin-top: 60px;
}

/* 下方提交区域 */
.submission-container {
    display: flex;
    justify-content: center;   /* ✅ 水平居中 */
    gap: 40px;
    margin: 80px auto;
}

/* 1. 容器样式：确保它占据整行宽度并水平居中 */
.submission-container {
    grid-column: 1 / -1;       /* 如果你在 grid 布局中，这确保它横跨所有列 */
    display: flex;
    justify-content: center;   /* 水平居中 */
    gap: 40px;                 /* 两个框之间的间距 */
    margin: 40px auto 100px auto; /* 上间距 40px，下间距 100px 留出空间给页脚 */
    width: 100%;
}

/* 2. 框体样式：添加圆角并去掉虚线（如果你想要更现代的实线） */
.submission-box {
    width: 320px;
    height: 120px;             /* 稍微调低高度更像长方形 */
    border: 2px solid #ffffff; /* 改为白色实线，呼应上方的 Project 边框 */
    border-radius: 25px;       /* 设置为 25px 圆角，与上方 Project 图片一致 */
    
    display: flex;
    align-items: center;
    justify-content: center;

    text-decoration: none;
    color: #ffffff;            /* 文字改为白色更符合深色背景 */
    font-size: 18px;
    font-weight: 500;
    background-color: rgba(255, 255, 255, 0.1); /* 半透明背景 */
    transition: all 0.3s ease;
}

/* 3. Hover 效果 */
.submission-box:hover {
    background-color: #ffffff;
    color: #000000;
    transform: translateY(-5px); /* 悬浮稍微往上动一下 */
}

.page-footer {
    margin-top: 100px;
    margin-bottom: 40px;
    text-align: center;
    font-size: 14px;
    letter-spacing: 0.5px;
    color: #ffffff;
}

.footer-email {
    margin-bottom: 8px;
}

.footer-email a {
    color: inherit;
    text-decoration: none;
}

.footer-email a:hover {
    text-decoration: underline;
}

.footer-copyright {
    font-size: 12px;
    opacity: 0.6;
}


/* ============================= */
/* RRR PAGE */
/* ============================= */
.rrr-page {
    background:#A7ADB0;
    height: 100vh;
}

.rrr-title {
    text-align: center;
    margin-top: 80px;
    font-size: 48px;
    color: white;
}

.rrr-grid {
    width: 70%;
    margin: 120px auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.rrr-box {
    height: 180px;
    background: #ffffff66;
    border: 2px solid white;
    border-radius: 22px;

    display: flex;
    justify-content: center;
    align-items: center;

    font-size: 22px;
    transition: 0.4s;

    text-decoration: none; /* ← 关键 */
    color: black;          /* ← 关键 */
}

.rrr-box:hover {
    transform: translateY(-8px) scale(1.05);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}
/* ============================= */
/* HOME PAGE */
/* ============================= */

.home-page {
    background: #D2CCCC;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 改为让 hero 100% 覆盖背景 */
.hero {
    width: 100%;
    height: 100vh; /* ← 全屏覆盖修复点 */
    background: url("bg1.jpg") center/cover no-repeat;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;

    animation: fadeIn 1.5s ease-out forwards;
    opacity: 0;
}

/* logo */
.hero-logo {
    width: 700px;
    opacity: 0;
    animation: fadeIn 1.6s ease forwards 0.4s;
}
/* 新增文字 */
.hero-text {
    margin-top: 25px;
    font-size: 22px;
    text-align: center;
    line-height: 1.6;
    color: white;

    opacity: 0;
    animation: fadeIn 1.8s ease forwards 0.8s;
}

/* 淡入动画 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(25px); }
    to { opacity: 1; transform: translateY(0); }
}