/* 下载页头部 */
.download-header {
    padding: calc(var(--header-height) + 4rem) 0 3rem;
    background: radial-gradient(circle at 30% 30%, rgba(99, 102, 241, 0.2) 0%, rgba(15, 23, 42, 0) 70%);
    text-align: center;
}

.download-header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.download-header p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
}

/* 下载选项 */
.download-options {
    padding: 1rem 0 4rem;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.download-card {
    background: linear-gradient(145deg, var(--bg-light), var(--bg-dark));
    border-radius: var(--radius-lg);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
    border: none;
    box-shadow: var(--shadow-sm);
}

.download-card.active {
    background: linear-gradient(145deg, var(--primary-dark), var(--bg-dark));
    box-shadow: var(--shadow-lg);
}

.download-card.active::before {
    content: '推荐';
    position: absolute;
    top: -0.75rem;
    right: -0.75rem;
    background: var(--gradient-accent);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
}

.download-card.disabled {
    opacity: 0.7;
    filter: grayscale(0.5);
}

.download-icon {
    width: 6rem;
    height: 6rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background: var(--bg-lighter);
    margin-bottom: 1.5rem;
    font-size: 3.5rem;
    color: white;
}

.download-card.active .download-icon {
    background: var(--gradient-primary);
}

.download-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.download-card p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.download-actions {
    margin-top: auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
}

.download-actions .btn {
    margin-bottom: 0.75rem;
    width: 100%;
}

.version {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* 系统要求 */
.system-requirements {
    padding: 5rem 0;
    background: radial-gradient(circle at 70% 50%, rgba(59, 130, 246, 0.1) 0%, rgba(15, 23, 42, 0) 70%);
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    margin-top: 3rem;
}

.requirement-card {
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    border: none;
    box-shadow: var(--shadow-sm);
}

.requirement-card:hover {
    transform: translateY(-5px);
    border-color: rgba(255, 255, 255, 0.1);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.requirement-icon {
    width: 3.5rem;
    height: 3.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background: var(--gradient-secondary);
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
    color: white;
}

.requirement-card:nth-child(1) .requirement-icon {
    background: var(--gradient-primary);
}

.requirement-card:nth-child(2) .requirement-icon {
    background: var(--gradient-secondary);
}

.requirement-card:nth-child(3) .requirement-icon {
    background: var(--gradient-accent);
}

.requirement-card:nth-child(4) .requirement-icon {
    background: linear-gradient(135deg, var(--success) 0%, var(--info) 100%);
}

.requirement-card h3 {
    margin-bottom: 0.5rem;
}

.requirement-card p {
    color: var(--text-secondary);
    margin-bottom: 0;
}

/* 安装指南 */
.installation-guide {
    padding: 5rem 0;
}

.guide-steps {
    max-width: 800px;
    margin: 3rem auto 0;
}

.step {
    display: flex;
    align-items: flex-start;
    margin-bottom: 3rem;
}

.step:last-child {
    margin-bottom: 0;
}

.step-number {
    width: 3rem;
    height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background: var(--gradient-primary);
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin-right: 1.5rem;
    flex-shrink: 0;
}

.step-content h3 {
    margin-bottom: 0.5rem;
}

.step-content p {
    color: var(--text-secondary);
    margin-bottom: 0;
}

/* FAQ 部分 */
.download-faq {
    padding: 5rem 0;
    background: radial-gradient(circle at 30% 50%, rgba(236, 72, 153, 0.1) 0%, rgba(15, 23, 42, 0) 70%);
}

.faq-items {
    max-width: 900px;
    margin: 3rem auto 0;
}

.faq-item {
    margin-bottom: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--bg-light);
    transition: all var(--transition-normal);
}

.faq-item:hover {
    border-color: rgba(255, 255, 255, 0.1);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.faq-question {
    padding: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
}

.faq-question h3 {
    margin-bottom: 0;
    font-size: 1.125rem;
}

.faq-toggle {
    width: 1.5rem;
    height: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background: var(--bg-lighter);
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.faq-item.active .faq-toggle {
    background: var(--primary-color);
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 1.5rem;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease;
}

.faq-item.active .faq-answer {
    padding: 0 1.5rem 1.5rem;
    max-height: 500px;
}

.faq-answer p {
    color: var(--text-secondary);
    margin-bottom: 0;
}

/* 在线选项 */
.online-option {
    padding: 5rem 0;
    text-align: center;
}

.online-content {
    max-width: 700px;
    margin: 0 auto;
    background: linear-gradient(145deg, var(--bg-light) 0%, var(--bg-dark) 100%);
    padding: 3rem 2rem;
    border-radius: var(--radius-lg);
    box-shadow: 0 20px 30px rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.online-content h2 {
    margin-bottom: 1rem;
}

.online-content p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .download-grid,
    .requirements-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .download-card.active {
        grid-column: 1 / 3;
    }
}

@media (max-width: 768px) {
    .download-header h1 {
        font-size: 2.5rem;
    }
    
    .step {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .step-number {
        margin-right: 0;
        margin-bottom: 1rem;
    }
}

@media (max-width: 576px) {
    .download-grid,
    .requirements-grid {
        grid-template-columns: 1fr;
    }
    
    .download-card.active {
        grid-column: auto;
    }
    
    .download-header h1 {
        font-size: 2rem;
    }
    
    .download-header p {
        font-size: 1rem;
    }
    
    .faq-question h3 {
        font-size: 1rem;
    }
}