/* ===== CSS 变量 ===== */
:root {
    --court-green: #1A4D2E;
    --basketball-orange: #FF6B35;
    --academic-navy: #0A1A2F;
    --light-bg: #F8F9FA;
    --white: #FFFFFF;
    --text-dark: #1A1A1A;
    --text-light: #FFFFFF;
    --text-muted: #6c757d;
    --border: #dee2e6;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.2);
}

/* ===== 全局重置 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: 'Montserrat', sans-serif;
    background: var(--light-bg);
    color: var(--text-dark);
    line-height: 1.7;
    overflow-x: hidden;
}

a { text-decoration: none; color: inherit; transition: color 0.3s; }

/* ===== 导航栏 ===== */
#navbar {
    position: fixed; top: 0; width: 100%;
    background: rgba(248, 249, 250, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: box-shadow 0.3s, background 0.3s;
}

#navbar.scrolled {
    box-shadow: var(--shadow);
    background: rgba(255, 255, 255, 0.95);
}

.nav-container {
    max-width: 1100px; margin: 0 auto;
    padding: 1rem 2rem;
    display: flex; justify-content: space-between; align-items: center;
}

.nav-logo {
    font-weight: 800; font-size: 1.3rem;
    color: var(--text-dark); letter-spacing: -0.5px;
}

.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a {
    color: var(--text-muted); font-weight: 500; font-size: 0.95rem;
    position: relative; padding: 0.25rem 0;
}
.nav-links a:hover, .nav-links a.active { color: var(--basketball-orange); }
.nav-links a.active::after {
    content: ''; position: absolute; bottom: -4px; left: 0;
    width: 100%; height: 2px; background: var(--basketball-orange);
}

.mobile-toggle {
    display: none; background: none; border: none; cursor: pointer;
    flex-direction: column; gap: 5px; padding: 0.5rem;
}
.mobile-toggle span {
    width: 24px; height: 2px; background: var(--text-dark);
    transition: all 0.3s;
}

/* ===== Hero ===== */
.hero {
    min-height: 100vh; display: flex; align-items: center;
    justify-content: center; text-align: center;
    position: relative; overflow: hidden;
    background: linear-gradient(135deg, var(--academic-navy) 0%, var(--court-green) 100%);
    animation: fadeIn 1.5s ease forwards;
}

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

.hero-overlay {
    position: absolute; inset: 0;
    background: radial-gradient(circle at 50% 50%, transparent 0%, rgba(0,0,0,0.3) 100%);
}

.hero-content {
    position: relative; z-index: 1; max-width: 700px; padding: 2rem;
}

.hero-greeting {
    font-size: 1.3rem; color: var(--basketball-orange);
    font-weight: 600; margin-bottom: 0.5rem;
    text-transform: uppercase; letter-spacing: 3px;
}

.hero-title {
    font-size: 4.5rem; font-weight: 900; line-height: 1.1;
    color: var(--white); margin-bottom: 1.5rem;
    letter-spacing: -2px;
}
.hero-title .highlight { color: var(--basketball-orange); }

.hero-desc {
    font-size: 1.2rem; color: rgba(255, 255, 255, 0.8);
    margin-bottom: 2.5rem; font-weight: 400;
}

.hero-actions {
    display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap;
}

.scroll-indicator {
    position: absolute; bottom: 2rem; left: 50%;
    transform: translateX(-50%);
    color: rgba(255, 255, 255, 0.5);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

/* ===== 按钮 ===== */
.btn-primary, .btn-secondary {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.85rem 2rem; border-radius: 4px;
    font-family: inherit; font-size: 0.95rem; font-weight: 600;
    cursor: pointer; transition: all 0.3s; border: none;
    text-transform: uppercase; letter-spacing: 1px;
}
.btn-primary {
    background: var(--basketball-orange); color: var(--white);
}
.btn-primary:hover {
    background: #e55a2b; transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 107, 53, 0.3);
}
.btn-primary svg { transition: transform 0.3s; }
.btn-primary:hover svg { transform: translateX(5px); }
.btn-secondary {
    background: transparent; color: var(--white);
    border: 1px solid rgba(255, 255, 255, 0.5);
}
.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1); border-color: var(--white);
    transform: translateY(-2px);
}

/* ===== 通用 Section ===== */
.section { max-width: 1100px; margin: 0 auto; padding: 6rem 2rem; }
.section-dark {
    max-width: 100%; background: var(--academic-navy);
}
.section-dark > * { max-width: 1100px; margin-left: auto; margin-right: auto; }

.section-title {
    font-size: 2.5rem; font-weight: 800; text-align: center;
    margin-bottom: 0.5rem; letter-spacing: -1px;
}
.section-title.light { color: var(--white); }
.section-title::after {
    content: ''; display: block; width: 60px; height: 3px;
    background: var(--basketball-orange); margin: 1rem auto 0;
}

.section-subtitle {
    text-align: center; color: var(--text-muted);
    font-size: 1.1rem; margin-bottom: 3rem; font-weight: 400;
}
.section-subtitle.light { color: rgba(255, 255, 255, 0.6); }

/* ===== About ===== */
.about-grid { display: flex; gap: 4rem; align-items: center; }
.about-text { flex: 1; }
.about-text p { color: #495057; margin-bottom: 1.5rem; font-size: 1.05rem; }
.about-text strong { color: var(--text-dark); font-weight: 700; }

.about-photos { flex: 0 0 420px; display: flex; flex-direction: column; gap: 1.5rem; }
.photo-card {
    position: relative; border-radius: 8px; overflow: hidden;
    box-shadow: var(--shadow); transition: transform 0.3s;
}
.photo-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.photo-card img { width: 100%; height: 300px; object-fit: cover; display: block; cursor: pointer; }
.photo-caption {
    position: absolute; bottom: 0; left: 0; right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.7));
    color: var(--white); padding: 1.5rem 1rem 0.75rem;
    font-size: 0.9rem; font-weight: 500;
}

/* 第二张照片向下偏移 */
.photo-offset {
    margin-top: 3rem;
}

/* ===== Highlights ===== */
.highlights-grid {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 2rem;
}
.highlight-card {
    background: rgba(255, 255, 255, 0.05); border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px; overflow: hidden; cursor: pointer;
    transition: all 0.3s;
}
.highlight-card:hover {
    transform: translateY(-4px); border-color: var(--basketball-orange);
    box-shadow: 0 8px 30px rgba(255, 107, 53, 0.2);
}
.highlight-thumbnail {
    aspect-ratio: 16/9; background: var(--court-green);
    display: flex; align-items: center; justify-content: center;
    position: relative; overflow: hidden;
}
.highlight-thumbnail img,
.highlight-thumbnail video {
    width: 100%; height: 100%; object-fit: cover; opacity: 0.7;
    transition: opacity 0.3s, transform 0.3s;
}
.highlight-card:hover .highlight-thumbnail img,
.highlight-card:hover .highlight-thumbnail video { opacity: 0.9; transform: scale(1.05); }
.play-icon {
    position: absolute; width: 60px; height: 60px;
    background: var(--basketball-orange); border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: var(--white); transition: transform 0.3s;
}
.highlight-card:hover .play-icon { transform: scale(1.1); }
.highlight-info { padding: 1.25rem; }
.highlight-info h3 { color: var(--white); font-size: 1.1rem; font-weight: 600; }
.highlight-info p { color: rgba(255, 255, 255, 0.5); font-size: 0.9rem; margin-top: 0.25rem; }

/* ===== Rehab ===== */
.rehab-grid { display: flex; gap: 4rem; align-items: flex-start; }
.rehab-text { flex: 1; }
.rehab-text h3 { font-size: 1.5rem; font-weight: 700; margin-bottom: 1rem; }
.rehab-text p { color: #495057; margin-bottom: 1.5rem; font-size: 1.05rem; }
.rehab-text strong { color: var(--text-dark); font-weight: 700; }

.rehab-posters {
    flex: 0 0 500px; display: grid; grid-template-columns: 1fr; gap: 2rem;
}
.poster-card {
    border-radius: 8px; overflow: hidden; box-shadow: var(--shadow);
    transition: transform 0.3s; cursor: pointer;
}
.poster-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.poster-card img { width: 100%; height: auto; display: block; cursor: pointer; }

/* ===== Research ===== */
.research-wrapper { max-width: 700px; margin: 0 auto; }
.research-content {
    background: rgba(255, 255, 255, 0.05); border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px; padding: 3rem 2.5rem; text-align: center;
    transition: transform 0.3s;
}
.research-content:hover { transform: translateY(-5px); }
.research-icon {
    width: 90px; height: 90px; margin: 0 auto 1.5rem;
    background: rgba(255, 107, 53, 0.15); border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: var(--basketball-orange);
}
.research-content h3 {
    color: var(--white); font-size: 1.5rem; font-weight: 700;
    margin-bottom: 1rem; line-height: 1.4;
}
.research-content p {
    color: rgba(255, 255, 255, 0.6); font-size: 1.05rem;
    margin-bottom: 2rem; line-height: 1.8;
}

/* ===== Contact ===== */
.contact-wrapper {
    text-align: center; max-width: 500px; margin: 0 auto; padding: 2rem 0;
}
.contact-intro {
    font-size: 1.1rem; color: var(--text-muted); margin-bottom: 2rem;
}
.contact-email {
    display: inline-flex; align-items: center; gap: 0.75rem;
    font-size: 1.2rem; color: var(--text-dark); font-weight: 600;
    border-bottom: 2px solid var(--basketball-orange);
    padding-bottom: 0.5rem; transition: all 0.3s;
}
.contact-email:hover { color: var(--basketball-orange); transform: translateY(-2px); }

/* ===== 页脚 ===== */
footer {
    text-align: center; padding: 2rem;
    border-top: 1px solid var(--border);
    color: var(--text-muted); font-size: 0.9rem;
}

/* ===== 灯箱 ===== */
.lightbox {
    display: none; position: fixed; inset: 0;
    background: rgba(0, 0, 0, 0.95); z-index: 2000;
    align-items: center; justify-content: center;
    flex-direction: column; padding: 2rem;
}
.lightbox.active { display: flex; }
.lightbox-img {
    max-width: 85vw; max-height: 75vh; object-fit: contain;
    border-radius: 8px; box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.lightbox-video {
    max-width: 85vw; max-height: 75vh;
    border-radius: 8px; box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.lightbox-close {
    position: absolute; top: 1.5rem; right: 2rem;
    font-size: 3rem; color: var(--white); cursor: pointer;
    line-height: 1; transition: color 0.3s;
}
.lightbox-close:hover { color: var(--basketball-orange); }
.lightbox-caption {
    color: var(--white); font-size: 1.1rem; margin-top: 1.5rem;
    font-weight: 500; text-align: center;
}

/* ===== 滚动动画 ===== */
.reveal {
    opacity: 0; transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-links {
        display: none; position: fixed; top: 0; left: 0;
        width: 100%; height: 100vh; background: var(--white);
        flex-direction: column; justify-content: center; align-items: center;
        gap: 2.5rem; z-index: 900;
    }
    .nav-links.active { display: flex; }
    .nav-links a { font-size: 1.5rem; color: var(--text-dark); }
    .mobile-toggle { display: flex; z-index: 999; }

    .hero-title { font-size: 2.5rem; }
    .hero-desc { font-size: 1rem; }

    .about-grid { flex-direction: column; }
    .about-photos { flex: none; width: 100%; }

    .highlights-grid { grid-template-columns: 1fr; }

    .rehab-grid { flex-direction: column; }
    .rehab-posters { flex: none; width: 100%; }

    .research-content { padding: 2rem 1.5rem; }
    .research-content h3 { font-size: 1.2rem; }
}