/* 基础样式 */
:root {
    --primary-color: #6c5ce7;
    --secondary-color: #a29bfe;
    --accent-color: #fd79a8;
    --dark-color: #2d3436;
    --light-color: #f5f6fa;
    --success-color: #00b894;
    --warning-color: #fdcb6e;
    --danger-color: #d63031;
    --text-color: #2d3436;
    --text-light: #636e72;
    --white: #ffffff;
    --gray-light: #dfe6e9;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 15px 30px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

body {
    background-color: var(--light-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮样式 */
.btn {
    padding: 10px 20px;
    border-radius: 30px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    border: none;
    font-size: 1rem;
}

.btn-outline {
    background-color: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    margin-right: 15px;
}

.btn-outline:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-primary:hover {
    background-color: #5649c0;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(108, 92, 231, 0.3);
}

.btn-sm {
    padding: 8px 15px;
    font-size: 0.9rem;
}

/* 头部样式 */
header {
    background-color: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-right: 10px;
}

.logo-text {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--dark-color);
}

.logo-text span {
    color: var(--primary-color);
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    font-size: 1.1rem;
    transition: var(--transition);
    position: relative;
}

nav ul li a:hover {
    color: var(--primary-color);
}

nav ul li a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

nav ul li a:hover::after {
    width: 100%;
}

nav ul li a.active {
    color: var(--primary-color);
}

nav ul li a.active::after {
    width: 100%;
}

.auth-buttons {
    display: flex;
    align-items: center;
}

.user-dropdown {
    position: relative;
    display: flex;
    align-items: center;
    cursor: pointer;
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    margin-right: 10px;
    object-fit: cover;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background-color: var(--white);
    box-shadow: var(--shadow-lg);
    border-radius: 5px;
    padding: 10px 0;
    min-width: 150px;
    display: none;
    z-index: 100;
}

.dropdown-menu a {
    display: block;
    padding: 8px 20px;
    color: var(--text-color);
    transition: var(--transition);
}

.dropdown-menu a:hover {
    background-color: var(--light-color);
    color: var(--primary-color);
}

.user-dropdown:hover .dropdown-menu {
    display: block;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 80px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50px;
    right: -50px;
    width: 200px;
    height: 200px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -80px;
    left: -80px;
    width: 300px;
    height: 300px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 800;
    position: relative;
    z-index: 1;
}

.hero p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto 30px;
    position: relative;
    z-index: 1;
}

.search-container {
    max-width: 700px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.search-input {
    width: 100%;
    padding: 18px 25px;
    border-radius: 50px;
    border: none;
    font-size: 1.1rem;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
}

.search-btn {
    position: absolute;
    right: 5px;
    top: 5px;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 50px;
    padding: 13px 25px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.search-btn:hover {
    background-color: #5649c0;
}

/* Tags Section */
.tags-section {
    padding: 50px 0 30px;
}

.section-title {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2rem;
    color: var(--dark-color);
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background-color: var(--primary-color);
    border-radius: 2px;
}

.tags-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
    margin-bottom: 30px;
}

.tag {
    padding: 8px 20px;
    background-color: var(--white);
    border-radius: 30px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
}

.tag:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: 0 5px 10px rgba(108, 92, 231, 0.2);
}

.tag.active {
    background-color: var(--primary-color);
    color: var(--white);
}

/* Projects Section */
.projects-section {
    padding: 50px 0;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.project-card {
    background-color: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.project-image {
    height: 180px;
    overflow: hidden;
    position: relative;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.project-card:hover .project-image img {
    transform: scale(1.05);
}

.project-badge {
    position: absolute;
    top: 15px;
    right: 15px;
    background-color: var(--accent-color);
    color: var(--white);
    padding: 5px 10px;
    border-radius: 5px;
    font-size: 0.8rem;
    font-weight: 600;
    z-index: 1;
}

.project-content {
    padding: 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.project-title {
    font-size: 1.2rem;
    margin-bottom: 10px;
    font-weight: 600;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.project-description {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 15px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    flex: 1;
}

.project-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
    margin-bottom: 10px;
}

.project-price {
    font-weight: 700;
    color: var(--primary-color);
}

.project-rating {
    color: var(--warning-color);
}

.view-all {
    text-align: center;
    margin-top: 40px;
}

/* Footer */
footer {
    background-color: var(--dark-color);
    color: var(--white);
    padding: 60px 0 20px;
    margin-top: auto;
}

.footer-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
}

.footer-logo-icon {
    font-size: 2rem;
    color: var(--primary-color);
    margin-right: 10px;
}

.footer-logo-text {
    font-size: 1.5rem;
    font-weight: 700;
}

.footer-about p {
    color: #b2bec3;
    margin-bottom: 20px;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    transition: var(--transition);
}

.social-link:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-links h3 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-links h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 3px;
    background-color: var(--primary-color);
}

.footer-links ul {
    list-style: none;
}

.footer-links ul li {
    margin-bottom: 10px;
}

.footer-links ul li a {
    color: #b2bec3;
    text-decoration: none;
    transition: var(--transition);
}

.footer-links ul li a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

.footer-contact p {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
    color: #b2bec3;
}

.footer-contact i {
    margin-right: 10px;
    color: var(--primary-color);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: #b2bec3;
    font-size: 0.9rem;
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    justify-content: center;
    align-items: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background-color: var(--white);
    border-radius: 10px;
    width: 90%;
    max-width: 500px;
    padding: 30px;
    position: relative;
    animation: modalFadeIn 0.3s;
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.close-modal {
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-light);
    transition: var(--transition);
}

.close-modal:hover {
    color: var(--text-color);
}

.auth-tabs {
    margin-top: 20px;
}

.tab-header {
    display: flex;
    border-bottom: 1px solid var(--gray-light);
    margin-bottom: 20px;
}

.tab-btn {
    padding: 10px 20px;
    background: none;
    border: none;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-light);
    cursor: pointer;
    position: relative;
    transition: var(--transition);
}

.tab-btn.active {
    color: var(--primary-color);
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
}

.tab-pane {
    display: none;
}

.tab-pane.active {
    display: block;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--gray-light);
    border-radius: 5px;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(108, 92, 231, 0.2);
}

.form-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 30px;
}

.forgot-password {
    color: var(--primary-color);
    font-size: 0.9rem;
    transition: var(--transition);
}

.forgot-password:hover {
    text-decoration: underline;
}

.social-login {
    margin-top: 30px;
    text-align: center;
}

.social-login p {
    color: var(--text-light);
    margin-bottom: 15px;
    position: relative;
}

.social-login p::before,
.social-login p::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 30%;
    height: 1px;
    background-color: var(--gray-light);
}

.social-login p::before {
    left: 0;
}

.social-login p::after {
    right: 0;
}

.social-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
}

.social-btn {
    padding: 10px 15px;
    border-radius: 5px;
    border: none;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 5px;
    transition: var(--transition);
}

.social-btn.wechat {
    background-color: #07C160;
    color: white;
}

.social-btn.weibo {
    background-color: #E6162D;
    color: white;
}

.social-btn.qq {
    background-color: #12B7F5;
    color: white;
}

.social-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.terms {
    margin-top: 20px;
    font-size: 0.8rem;
    color: var(--text-light);
    text-align: center;
}

.terms a {
    color: var(--primary-color);
    transition: var(--transition);
}

.terms a:hover {
    text-decoration: underline;
}

/* 项目详情页样式 */
.project-detail-section {
    padding: 50px 0;
}

.breadcrumb {
    margin-bottom: 20px;
    font-size: 0.9rem;
    color: var(--text-light);
}

.breadcrumb a {
    color: var(--primary-color);
    transition: var(--transition);
}

.breadcrumb a:hover {
    text-decoration: underline;
}

.project-detail-header {
    margin-bottom: 40px;
}

.project-title {
    font-size: 2.2rem;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.project-subtitle {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 20px;
}

.project-meta {
    display: flex;
    align-items: center;
    gap: 30px;
    margin-bottom: 20px;
}

.instructor-info {
    display: flex;
    align-items: center;
    gap: 10px;
}

.instructor-info img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
}

.stats {
    display: flex;
    align-items: center;
    gap: 20px;
}

.stats span {
    display: flex;
    align-items: center;
    gap: 5px;
    font-size: 0.9rem;
    color: var(--text-light);
}

.project-detail-content {
    display: flex;
    gap: 30px;
}

.project-main {
    flex: 1;
}

.project-cover {
    margin-bottom: 30px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.project-cover img {
    width: 100%;
    height: auto;
    display: block;
}

.project-info {
    background-color: var(--white);
    border-radius: 10px;
    padding: 20px;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
}

.price-section {
    margin-bottom: 20px;
}

.original-price {
    text-decoration: line-through;
    color: var(--text-light);
    font-size: 1rem;
}

.current-price {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    margin: 5px 0 15px;
}

.share-section {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: 20px;
}

.share-btn {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 1rem;
    transition: var(--transition);
}

.share-btn.wechat {
    background-color: #07C160;
}

.share-btn.weibo {
    background-color: #E6162D;
}

.share-btn.qq {
    background-color: #12B7F5;
}

.share-btn:hover {
    transform: translateY(-2px);
}

.project-tabs {
    background-color: var(--white);
    border-radius: 10px;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.project-tabs .tab-header {
    display: flex;
    border-bottom: 1px solid var(--gray-light);
    padding: 0 20px;
}

.project-tabs .tab-btn {
    padding: 15px 20px;
    font-size: 1rem;
    color: var(--text-light);
    position: relative;
    background: none;
    border: none;
    cursor: pointer;
}

.project-tabs .tab-btn.active {
    color: var(--primary-color);
    font-weight: 600;
}

.project-tabs .tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
}

.tab-content {
    padding: 30px;
}

.tab-content h3 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--dark-color);
}

.project-description {
    line-height: 1.8;
    margin-bottom: 20px;
}

.highlights {
    list-style: none;
    margin-left: 20px;
}

.highlights li {
    position: relative;
    padding-left: 25px;
    margin-bottom: 10px;
}

.highlights li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

.chapter-list {
    border-radius: 8px;
    overflow: hidden;
}

.chapter-item {
    margin-bottom: 20px;
    border: 1px solid var(--gray-light);
    border-radius: 8px;
    overflow: hidden;
}

.chapter-header {
    background-color: var(--light-color);
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}

.chapter-header h4 {
    font-size: 1.1rem;
    color: var(--dark-color);
}

.chapter-header span {
    font-size: 0.9rem;
    color: var(--text-light);
}

.lesson-list {
    padding: 0 20px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.chapter-item.active .lesson-list {
    max-height: 1000px;
    padding-bottom: 15px;
}

.lesson-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px dashed var(--gray-light);
}

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

.lesson-item.free {
    background-color: rgba(0, 184, 148, 0.05);
}

.lesson-info {
    display: flex;
    align-items: center;
    gap: 10px;
}

.lesson-info i {
    color: var(--primary-color);
}

.free-label {
    background-color: var(--success-color);
    color: white;
    font-size: 0.7rem;
    padding: 2px 8px;
    border-radius: 10px;
    margin-left: 10px;
}

.lesson-duration {
    font-size: 0.8rem;
    color: var(--text-light);
}

.instructor-detail {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
}

.instructor-avatar img {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--primary-color);
}

.instructor-info h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.specialty {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 15px;
}

.instructor-stats {
    display: flex;
    gap: 20px;
    margin-top: 20px;
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-light);
}

.experience-content {
    line-height: 1.8;
}

.comment-list {
    margin-bottom: 30px;
}

.comment-item {
    background-color: var(--white);
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
}

.comment-user {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
}

.comment-user img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
}

.comment-rate {
    margin-bottom: 10px;
}

.comment-rate i {
    color: var(--warning-color);
    font-size: 0.9rem;
}

.comment-rate i.active {
    color: var(--warning-color);
}

.comment-content {
    line-height: 1.6;
    margin-bottom: 10px;
}

.comment-time {
    font-size: 0.8rem;
    color: var(--text-light);
}

.no-comments {
    text-align: center;
    padding: 40px 0;
    color: var(--text-light);
}

.comment-form {
    background-color: var(--white);
    border-radius: 8px;
    padding: 20px;
    box-shadow: var(--shadow);
}

.comment-form h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--dark-color);
}

.rate-section {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 15px;
}

.rate-stars {
    display: flex;
    gap: 5px;
}

.rate-stars i {
    color: var(--gray-light);
    cursor: pointer;
    font-size: 1.2rem;
    transition: var(--transition);
}

.rate-stars i.active,
.rate-stars i:hover {
    color: var(--warning-color);
}

.comment-form textarea {
    width: 100%;
    min-height: 120px;
    padding: 15px;
    border: 1px solid var(--gray-light);
    border-radius: 5px;
    resize: vertical;
    font-family: inherit;
    transition: var(--transition);
}

.comment-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(108, 92, 231, 0.2);
}

.project-sidebar {
    width: 300px;
}

.sidebar-section {
    background-color: var(--white);
    border-radius: 10px;
    padding: 20px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.sidebar-section h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--dark-color);
    padding-bottom: 10px;
    border-bottom: 1px solid var(--gray-light);
}

.related-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 15px;
}

.related-item {
    display: flex;
    gap: 10px;
}

.related-item img {
    width: 80px;
    height: 60px;
    border-radius: 5px;
    object-fit: cover;
}

.related-item h4 {
    font-size: 0.9rem;
    margin-bottom: 5px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.related-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
}

.related-meta .price {
    color: var(--primary-color);
    font-weight: 600;
}

.related-meta .rate {
    color: var(--warning-color);
}

.project-tags .tags-container {
    justify-content: flex-start;
}

.notice-list {
    list-style: none;
}

.notice-list li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 10px;
}

.notice-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* 分类页和标签页样式 */
.category-section,
.tag-section {
    padding: 50px 0;
}

.category-title,
.tag-title {
    font-size: 2rem;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.category-description,
.tag-description {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 30px;
}

.category-filters,
.tag-filters {
    margin-bottom: 30px;
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 15px;
}

.filter-group span {
    font-weight: 500;
}

.filter-btn {
    padding: 8px 15px;
    background-color: var(--white);
    border-radius: 5px;
    font-size: 0.9rem;
    color: var(--text-light);
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.filter-btn.active {
    background-color: var(--primary-color);
    color: var(--white);
}

.filter-btn:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

.pagination {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 40px;
}

.page-btn {
    padding: 8px 15px;
    background-color: var(--white);
    border-radius: 5px;
    font-size: 0.9rem;
    color: var(--text-light);
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.page-btn.active {
    background-color: var(--primary-color);
    color: var(--white);
}

.page-btn:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

/* 错误提示 */
.alert {
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
    font-size: 0.9rem;
}

.alert-danger {
    background-color: rgba(214, 48, 49, 0.1);
    color: var(--danger-color);
}

/* Responsive Styles */
@media (max-width: 1200px) {
    .project-detail-content {
        flex-direction: column;
    }
    
    .project-sidebar {
        width: 100%;
    }
}

@media (max-width: 992px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero p {
        font-size: 1.1rem;
    }
    
    .project-title {
        font-size: 1.8rem;
    }
}

@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        padding: 15px 0;
    }
    
    .logo {
        margin-bottom: 15px;
    }
    
    nav ul li {
        margin-left: 15px;
    }
    
    .auth-buttons {
        margin-top: 15px;
    }
    
    .hero {
        padding: 60px 0;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .project-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 15px;
    }
    
    .footer-container {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 576px) {
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    nav ul li {
        margin: 5px 10px;
    }
    
    .search-input {
        padding: 15px 20px;
    }
    
    .search-btn {
        padding: 10px 15px;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-container {
        grid-template-columns: 1fr;
    }
    
    .tab-header {
        flex-direction: column;
    }
    
    .tab-btn {
        width: 100%;
        text-align: center;
    }
    
    .social-buttons {
        flex-direction: column;
    }
    
    .social-btn {
        justify-content: center;
    }
    
    .filter-group {
        flex-wrap: wrap;
    }
    
    .project-tabs .tab-header {
        flex-wrap: wrap;
    }
    
    .instructor-detail {
        flex-direction: column;
    }
}

/* 新增的登录/注册弹窗样式 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(5px);
}

.modal.show {
    display: flex;
}

.modal-content {
    background-color: var(--white);
    border-radius: 15px;
    width: 90%;
    max-width: 450px;
    padding: 30px;
    position: relative;
    animation: modalFadeIn 0.3s;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.close-modal {
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 1.8rem;
    cursor: pointer;
    color: var(--text-light);
    transition: var(--transition);
    background: none;
    border: none;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.close-modal:hover {
    color: var(--danger-color);
    background-color: rgba(214, 48, 49, 0.1);
}

.auth-tabs {
    margin-top: 10px;
}

.tab-header {
    display: flex;
    border-bottom: 1px solid var(--gray-light);
    margin-bottom: 25px;
}

.tab-btn {
    padding: 12px 25px;
    background: none;
    border: none;
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-light);
    cursor: pointer;
    position: relative;
    transition: var(--transition);
}

.tab-btn.active {
    color: var(--primary-color);
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
    border-radius: 3px 3px 0 0;
}

.tab-pane {
    display: none;
    animation: fadeIn 0.3s;
}

.tab-pane.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input {
    width: 100%;
    padding: 14px 15px;
    border: 1px solid var(--gray-light);
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
    background-color: rgba(245, 246, 250, 0.5);
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.2);
}

.form-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 30px;
}

.forgot-password {
    color: var(--primary-color);
    font-size: 0.9rem;
    transition: var(--transition);
}

.forgot-password:hover {
    text-decoration: underline;
}

.social-login {
    margin-top: 30px;
    text-align: center;
}

.social-login p {
    color: var(--text-light);
    margin-bottom: 15px;
    position: relative;
}

.social-login p::before,
.social-login p::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 30%;
    height: 1px;
    background-color: var(--gray-light);
}

.social-login p::before {
    left: 0;
}

.social-login p::after {
    right: 0;
}

.social-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 20px;
}

.social-btn {
    padding: 10px 20px;
    border-radius: 8px;
    border: none;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.social-btn i {
    font-size: 1.1rem;
}

.social-btn.wechat {
    background-color: #07C160;
    color: white;
}

.social-btn.weibo {
    background-color: #E6162D;
    color: white;
}

.social-btn.qq {
    background-color: #12B7F5;
    color: white;
}

.social-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.15);
}

.terms {
    margin-top: 25px;
    font-size: 0.8rem;
    color: var(--text-light);
    text-align: center;
    line-height: 1.6;
}

.terms a {
    color: var(--primary-color);
    transition: var(--transition);
    font-weight: 500;
}

.terms a:hover {
    text-decoration: underline;
}

/* 响应式调整 */
@media (max-width: 576px) {
    .modal-content {
        padding: 20px;
    }
    
    .tab-header {
        flex-direction: column;
    }
    
    .tab-btn {
        width: 100%;
        text-align: center;
        padding: 12px;
    }
    
    .social-buttons {
        flex-direction: column;
    }
    
    .social-btn {
        justify-content: center;
    }
}