/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

/* 头部样式 */
header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    padding: 1.2rem 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    margin-left: 2rem;
    display: inline-block;
    vertical-align: middle;
}

.logo img {
    height: 3.5rem;
    width: auto;
    vertical-align: middle;
    margin-right: 0.5rem;
    image-rendering: pixelated;
    image-rendering: crisp-edges;
}

/* 导航样式 */
nav {
    display: inline-block;
    vertical-align: middle;
    margin-left: 3rem;
}

nav ul {
    list-style: none;
}

nav ul li {
    display: inline;
    margin-left: 1.5rem;
}

nav ul li a {
    color: #fff;
    text-decoration: none;
    font-size: 1rem;
    transition: color 0.3s ease;
}

nav ul li a:hover {
    color: #f4f4f4;
    text-decoration: underline;
}

nav ul li a.active {
    font-weight: bold;
    text-decoration: underline;
}

/* 标题样式 */
h1 {
    text-align: center;
    margin: 3rem 0;
    color: #667eea;
    font-size: 2.5rem;
}

/* 404页面样式 */
h2 {
    text-align: center;
    margin: 1rem 0;
    color: #667eea;
}

/* 歌曲标题样式 */
h3 {
    text-align: center;
    margin: 1.5rem 0 1rem 0;
    color: #667eea;
    font-size: 1.3rem;
}

p {
    text-align: center;
    margin: 1rem 0;
}

/* 网站地图样式 */
.sitemap-container {
    width: 95%;
    max-width: 1100px;
    margin: 2rem auto;
    padding: 1.5rem;
    background-color: #f9f9f9;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.sitemap-list {
    list-style: none;
    padding: 0;
}

.sitemap-list li {
    margin: 0.8rem 0;
    font-size: 1.1rem;
}

.sitemap-list li a {
    color: #333;
    text-decoration: none;
    transition: color 0.3s ease;
}

.sitemap-list li a:hover {
    color: #555;
    text-decoration: underline;
}

/* 资源列表可滑动样式 */
.scrollable-container {
    width: 95%;
    max-width: 1100px;
    margin: 2rem auto;
    padding: 1.5rem;
    background-color: #f9f9f9;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    max-height: 400px;
    overflow-y: auto;
}

.resource-list {
    list-style: none;
    padding: 0;
}

.resource-list li {
    margin: 0.8rem 0;
    font-size: 1.1rem;
    padding: 0.5rem;
    background-color: #fff;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.resource-list li:hover {
    background-color: #e9e9e9;
}

.resource-list li a {
    color: #333;
    text-decoration: none;
    display: block;
}

.resource-list li a:hover {
    color: #555;
    text-decoration: underline;
}

/* 视频样式 */
video {
    display: block;
    margin: 2rem auto;
    width: 85%;
    max-width: 900px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

/* 更新日志样式 */
.changelog-container {
    width: 95%;
    max-width: 1100px;
    margin: 2rem auto;
    padding: 0;
}

.changelog-year {
    text-align: center;
    margin-bottom: 2rem;
    color: #667eea;
    font-size: 1.8rem;
    font-weight: bold;
}

.changelog-day {
    background-color: #fff;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
    overflow: hidden;
}

.changelog-date {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    padding: 1rem 1.5rem;
    font-size: 1.2rem;
    font-weight: bold;
}

.changelog-time-item {
    padding: 1.5rem;
    border-bottom: 1px solid #f0f0f0;
}

.changelog-time-item:last-child {
    border-bottom: none;
}

.changelog-time {
    color: #667eea;
    font-weight: bold;
    font-size: 1rem;
    margin-bottom: 1rem;
}

.changelog-list {
    list-style: none;
    padding: 0;
}

.changelog-list li {
    padding: 0.6rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: #444;
    font-size: 1rem;
}

.changelog-list li:before {
    content: "•";
    color: #667eea;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* 底部样式 */
#footer-placeholder {
    margin-top: auto;
}

footer {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    text-align: center;
    padding: 1.5rem 0;
}

footer p {
    margin: 0;
    color: #fff;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header {
        text-align: center;
        padding: 1rem;
    }

    .logo {
        display: block;
        margin: 0 0 1rem 0;
    }

    nav {
        display: block;
        margin: 0;
    }

    nav ul li {
        display: block;
        margin: 0.5rem 0;
    }

    h1 {
        font-size: 2rem;
        margin: 2rem 0;
        padding: 0 1rem;
    }

    video {
        width: 95%;
    }

    .changelog-time-item {
        padding: 1rem;
    }
}

/* 留言板样式 */
.guestbook-container {
    width: 95%;
    max-width: 1100px;
    margin: 2rem auto;
}

.guestbook-form,
.guestbook-messages {
    background-color: #fff;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.guestbook-form h2,
.guestbook-messages h2 {
    color: #667eea;
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: #333;
    font-weight: bold;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    box-sizing: border-box;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.submit-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.message-item {
    background-color: #f9f9f9;
    border-radius: 8px;
    padding: 1.2rem;
    margin-bottom: 1rem;
    position: relative;
}

.message-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.8rem;
}

.message-name {
    color: #667eea;
    font-weight: bold;
    font-size: 1.1rem;
}

.message-time {
    color: #999;
    font-size: 0.9rem;
}

.message-content {
    color: #333;
    line-height: 1.6;
}

.message-ip {
    color: #999;
    font-size: 0.85rem;
    margin-top: 0.8rem;
    padding-top: 0.8rem;
    border-top: 1px dashed #e0e0e0;
}

.message-location {
    color: #667eea;
    font-size: 0.85rem;
    margin-top: 0.5rem;
}

.delete-btn {
    position: absolute;
    top: 0.8rem;
    right: 0.8rem;
    background-color: #ff4444;
    color: #fff;
    border: none;
    border-radius: 4px;
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.delete-btn:hover {
    background-color: #cc0000;
}

@media (max-width: 768px) {
    .message-header {
        flex-direction: column;
        gap: 0.5rem;
    }

    .delete-btn {
        position: static;
        margin-top: 1rem;
        width: 100%;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.8rem;
    }

    video {
        width: 100%;
        border-radius: 0;
    }
}