:root {
    --primary-color: #4285f4;
    --text-primary: #333;
    --text-secondary: #666;
    --background-light: #f8f9fa;
    --background-section: #eef9ff;
    --card-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    line-height: 1.6;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: #fff;
}

header {
    padding: 1rem 2rem;
    background: #fff;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.logo {
    font-size: 1.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: bold;
}

main {
    max-width: 1400px;  
    margin: 0 auto;
    padding: 2rem;
}

/* Profile Section */
.profile {
    margin: 2rem auto 6rem;  
    max-width: 1200px;
    padding: 0 2rem;
}

.profile-content {
    display: flex;
    gap: 4rem;  
    align-items: center;
}

.profile-image {
    flex-shrink: 0;
}

.avatar {
    width: 240px;
    height: 240px;
    border-radius: 24px;
    object-fit: cover;
}

.profile-info {
    flex: 1;
}

.profile-info h1 {
    font-size: 3rem;  
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.profile-info h2 {
    font-size: 1.4rem;  
    color: var(--text-secondary);
    font-weight: 400;
    margin-bottom: 2rem;
}

.achievements {
    margin: 2rem 0;  
}

.achievement-item {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;  
    font-size: 1.1rem;  
}

.achievement-item .icon {
    margin-right: 1rem;
    font-size: 1.4rem;  
}

.social-links {
    display: flex;
    gap: 1rem;  
    margin-top: 2rem;
    flex-wrap: wrap;  
}

.social-btn {
    display: flex;
    align-items: center;
    padding: 0.75rem 1.2rem;  
    border-radius: 10px;
    text-decoration: none;
    color: var(--text-primary);
    background: var(--background-light);
    transition: all 0.3s ease;
    font-size: 1rem;  
    cursor: pointer;  
}

.social-btn:hover {
    transform: translateY(-2px);
    background: #edf1f7;  
}

.social-btn img {
    width: 24px;  
    height: 24px;
    margin-right: 0.75rem;
}

.social-btn.wechat,
.social-btn.qq {
    position: relative;
}

.social-btn.wechat .qr-code,
.social-btn.qq .qr-code {
    position: absolute;
    bottom: calc(100% + 10px);
    left: 50%;
    transform: translateX(-50%);
    width: 200px;
    height: 200px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    pointer-events: none;
    background: #fff;
    padding: 8px;
}

.social-btn.wechat .qr-code.show,
.social-btn.qq .qr-code.show {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.social-btn.wechat .qr-code img,
.social-btn.qq .qr-code img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.social-btn.wechat:hover .qr-code,
.social-btn.qq:hover .qr-code {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.social-btn.wechat .qr-code::after,
.social-btn.qq .qr-code::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border-width: 8px;
    border-style: solid;
    border-color: #fff transparent transparent transparent;
}

/* Content Sections Background */
.content-sections {
    background: var(--background-section);
    margin: 0 auto;
    padding: 4rem 2rem;
    max-width: 1400px;
}

.content-sections > section {
    max-width: 1200px;
    margin: 0 auto 4rem;
}

/* Apps Section */
.app-grid, .project-grid, .tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));  
    gap: 2rem;
    margin-top: 2rem;
}

.app-card, .project-card, .tool-card {
    background: #fff;
    border-radius: 16px;  
    padding: 2rem;  
    box-shadow: var(--card-shadow);
    transition: all 0.3s ease;
    border: 1px solid rgba(0, 0, 0, 0.06);
}

.app-card:hover, .project-card:hover, .tool-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);  
}

.app-icon {
    width: 72px;
    height: 72px;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.app-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    border-radius: 16px;
}

h2 {
    font-size: 2rem;  
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

h3 {
    font-size: 1.4rem;  
    margin-bottom: 1rem;
}

.app-link, .project-link {
    display: inline-block;
    margin-top: 1.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    font-size: 1.1rem;  
}

.app-link:hover, .project-link:hover {
    text-decoration: underline;
}

.app-meta {
    display: flex;
    gap: 1.5rem;
    margin: 1.5rem 0;
    color: var(--text-secondary);
    font-size: 1rem;
}

.downloads, .rating {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tech-stack {
    display: flex;
    gap: 0.75rem;
    margin: 1.5rem 0;
    flex-wrap: wrap;
}

.tech-tag {
    background: var(--background-light);
    padding: 0.5rem 1rem;
    border-radius: 1rem;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.tool-card {
    text-align: center;
    padding: 2.5rem 2rem;
}

.tool-icon, .platform-icon {
    width: 56px;  
    height: 56px;
    margin: 0 auto 1.5rem auto;
}

.tool-icon img, .platform-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.tool-link, .platform-link {
    display: inline-block;
    margin-top: 1.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    font-size: 1.1rem;
}

.tool-link:hover, .platform-link:hover {
    text-decoration: underline;
}

.tool-links {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.tool-link {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

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

.tool-link:not(.primary) {
    background: var(--background-light);
    color: var(--text-primary);
}

.tool-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.tool-link.primary:hover {
    background: #3b78e7;
}

.tool-link:not(.primary):hover {
    background: #edf1f7;
}

section {
    margin-bottom: 4rem;
    padding-bottom: 2rem;
}

section:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.platform-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.platform-card {
    background: #fff;
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--card-shadow);
    transition: transform 0.3s ease;
    text-align: center;
}

.platform-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

footer {
    text-align: center;
    padding: 2rem;
    color: var(--text-secondary);
    background: var(--background-light);
    margin-top: 0;  
}

/* Responsive Design */
@media (max-width: 768px) {
    .profile-content {
        flex-direction: column;
        text-align: center;
        gap: 2rem;
    }

    .social-links {
        justify-content: center;
    }

    .achievement-item {
        justify-content: center;
    }
    
    .app-grid, .project-grid, .tools-grid {
        grid-template-columns: 1fr;
    }
    
    .tech-stack {
        justify-content: center;
    }
    
    .app-meta {
        justify-content: center;
    }
}