/* 
 * 社会实践成果展示网站 - Core Styles
 * 美观优先，基于 Bootstrap 5 定制
 */

:root {
    --primary-color: #2c3e50;
    --secondary-color: #e74c3c;
    --accent-color: #3498db;
    --bg-light: #f8f9fa;
    --text-main: #2c3e50;
    --text-muted: #6c757d;
    --border-radius-lg: 1rem;
    --box-shadow-sm: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    --box-shadow-hover: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
    --transition-base: all 0.3s ease-in-out;
}

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--text-main);
    background-color: #fff;
    line-height: 1.6;
    overflow-x: hidden;
}

/* === Navigation === */
.navbar {
    backdrop-filter: blur(10px);
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: var(--box-shadow-sm);
    padding: 1rem 0;
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-color) !important;
}

.nav-link {
    font-weight: 500;
    color: var(--text-main) !important;
    padding: 0.5rem 1rem !important;
    transition: var(--transition-base);
}

.nav-link:hover, .nav-link.active {
    color: var(--accent-color) !important;
}

/* === Hero Section === */
.hero-section {
    position: relative;
    height: 80vh;
    min-height: 500px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-content {
    z-index: 2;
    position: relative;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

/* === Cards & Projects === */
.project-card {
    border: none;
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    transition: var(--transition-base);
    background: #fff;
    box-shadow: var(--box-shadow-sm);
    height: 100%;
}

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

.project-img-wrapper {
    position: relative;
    overflow: hidden;
    padding-top: 60%; /* 16:9 Aspect Ratio */
}

.project-img-wrapper img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

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

.card-body {
    padding: 1.5rem;
}

.card-title {
    font-weight: 700;
    margin-bottom: 0.75rem;
}

.badge-custom {
    padding: 0.5em 0.8em;
    border-radius: 2rem;
    font-weight: 500;
    font-size: 0.75rem;
}

/* === Timeline Component === */
.timeline {
    position: relative;
    padding: 2rem 0;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #e9ecef;
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
}

.timeline-dot {
    position: absolute;
    left: 50%;
    top: 0;
    width: 16px;
    height: 16px;
    background: var(--accent-color);
    border-radius: 50%;
    transform: translateX(-50%);
    z-index: 2;
    border: 3px solid #fff;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

.timeline-content {
    width: 45%;
    padding: 1.5rem;
    background: #fff;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--box-shadow-sm);
    position: relative;
    transition: var(--transition-base);
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-left: auto;
}

.timeline-item:hover .timeline-content {
    transform: translateY(-5px);
    box-shadow: var(--box-shadow-hover);
}

.timeline-date {
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
    display: block;
}

/* === Team Members === */
.member-card {
    text-align: center;
    padding: 2rem;
    background: #fff;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--box-shadow-sm);
    transition: var(--transition-base);
}

.member-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--box-shadow-hover);
}

.member-avatar {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    margin: 0 auto 1.5rem;
    object-fit: cover;
    border: 3px solid #fff;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

/* === Footer === */
footer {
    background-color: #f8f9fa;
    padding: 4rem 0 2rem;
    margin-top: 4rem;
}

/* === Responsive Adjustments === */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-dot {
        left: 20px;
    }
    
    .timeline-content {
        width: calc(100% - 50px);
        margin-left: 50px !important;
    }
}