/* 全局样式 */
:root {
    --primary-color: #4a6cf7;
    --secondary-color: #6c757d;
    --dark-color: #212529;
    --light-color: #f8f9fa;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --body-bg: #f5f8ff;
    --card-bg: #ffffff;
    --transition: all 0.3s ease;
    --shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 8px 28px rgba(0, 0, 0, 0.15);
    --gradient: linear-gradient(135deg, #4a6cf7 0%, #2b50ed 100%);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--body-bg);
    color: var(--dark-color);
    line-height: 1.6;
    overflow-x: hidden;
}

/* 导航栏样式 */
.navbar {
    background: var(--gradient);
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

.navbar-brand {
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
}

.navbar-dark .navbar-nav .nav-link {
    color: rgba(255, 255, 255, 0.85);
    font-weight: 500;
    padding: 0.5rem 1rem;
    transition: var(--transition);
}

.navbar-dark .navbar-nav .nav-link:hover,
.navbar-dark .navbar-nav .nav-link.active {
    color: #ffffff;
}

/* 英雄区域样式 */
.hero-section {
    background: var(--gradient);
    color: white;
    padding: 8rem 0 6rem;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('../img/pattern.svg');
    background-size: cover;
    opacity: 0.1;
    z-index: 0;
}

.hero-section .container {
    position: relative;
    z-index: 1;
}

.hero-section h1 {
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.hero-section .lead {
    font-size: 1.25rem;
    max-width: 600px;
    margin: 0 auto;
}

.download-btn {
    padding: 0.75rem 2rem;
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(74, 108, 247, 0.4);
    transition: var(--transition);
}

.download-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(74, 108, 247, 0.6);
}

/* 功能特点样式 */
.features-section {
    padding: 6rem 0;
    background-color: var(--light-color);
}

.feature-card {
    background-color: var(--card-bg);
    border-radius: 10px;
    padding: 2rem;
    height: 100%;
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

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

.icon-wrapper {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(74, 108, 247, 0.1);
    border-radius: 50%;
}

.icon-wrapper i {
    font-size: 2rem;
    color: var(--primary-color);
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

/* 下载区域样式 */
.download-section {
    padding: 6rem 0;
    background-color: #ffffff;
}

.os-detection-message {
    background-color: rgba(74, 108, 247, 0.1);
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 3rem;
}

#detected-os {
    color: var(--primary-color);
}

.download-options {
    margin-bottom: 4rem;
}

.download-options h3 {
    font-weight: 600;
    margin-bottom: 2rem;
}

.download-card {
    background-color: var(--card-bg);
    border-radius: 10px;
    padding: 2rem;
    height: 100%;
    box-shadow: var(--shadow);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.download-card:hover {
    box-shadow: var(--shadow-hover);
}

.download-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.download-card p {
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.architecture-options {
    display: flex;
    gap: 10px;
}

.download-info {
    margin-top: auto;
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--secondary-color);
}

.download-info span {
    display: flex;
    align-items: center;
    gap: 5px;
}

/* 常见问题样式 */
.faq-section {
    padding: 6rem 0;
    background-color: var(--light-color);
}

.accordion-item {
    border: none;
    margin-bottom: 1rem;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.accordion-button {
    font-weight: 600;
    padding: 1.25rem;
    background-color: var(--card-bg);
}

.accordion-button:not(.collapsed) {
    color: var(--primary-color);
    background-color: rgba(74, 108, 247, 0.05);
    box-shadow: none;
}

.accordion-button:focus {
    box-shadow: none;
    border-color: rgba(74, 108, 247, 0.5);
}

.accordion-body {
    padding: 1.25rem;
    background-color: var(--card-bg);
}

/* 页脚样式 */
.footer {
    background-color: var(--dark-color);
    color: #ffffff;
    padding: 4rem 0 2rem;
}

.footer h5 {
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: #ffffff;
}

.footer ul li {
    margin-bottom: 0.75rem;
}

.footer a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer a:hover {
    color: #ffffff;
    text-decoration: none;
}

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 1.5rem;
}

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

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

.footer hr {
    margin: 2rem 0;
    opacity: 0.1;
}

/* 下载成功模态框样式 */
.download-success-icon {
    font-size: 4rem;
    color: var(--success-color);
}

.download-details {
    background-color: rgba(40, 167, 69, 0.1);
    padding: 1rem;
    border-radius: 8px;
}

.download-details p {
    margin-bottom: 0.5rem;
}

/* 响应式调整 */
@media (max-width: 991.98px) {
    .hero-section {
        padding: 6rem 0 4rem;
    }
    
    .features-section,
    .download-section,
    .faq-section {
        padding: 4rem 0;
    }
}

@media (max-width: 767.98px) {
    .hero-section {
        padding: 4rem 0 3rem;
    }
    
    .hero-section h1 {
        font-size: 2.5rem;
    }
    
    .features-section,
    .download-section,
    .faq-section {
        padding: 3rem 0;
    }
    
    .download-card {
        padding: 1.5rem;
    }
}

/* 动画效果 */
.animate__animated {
    animation-duration: 0.8s; /* 稍微加快动画速度 */
}

.animate__delay-1s {
    animation-delay: 0.5s;
}

/* 滚动动画初始状态 - 避免闪烁 */
.reveal-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
    will-change: opacity, transform;
}

.reveal-on-scroll.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* 推荐版本标记 */
.recommended-badge {
    position: absolute;
    top: -12px;
    right: 20px;
    background: linear-gradient(135deg, #ff9966 0%, #ff5e62 100%);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 700;
    box-shadow: 0 4px 10px rgba(255, 94, 98, 0.4);
    z-index: 2;
    transform: translateY(-10px);
    opacity: 0;
    transition: all 0.5s cubic-bezier(0.68, -0.55, 0.27, 1.55);
}

.download-card.recommended {
    border: 2px solid var(--primary-color);
    transform: translateY(-15px);
    box-shadow: 0 15px 35px rgba(74, 108, 247, 0.2);
    position: relative;
}

.download-card.recommended .recommended-badge {
    transform: translateY(0);
    opacity: 1;
}

/* 视差滚动背景 */
.parallax-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 120%; /* 比容器高，以便滚动 */
    background-image: url('../img/pattern.svg');
    background-size: cover;
    opacity: 0.1;
    z-index: 0;
    pointer-events: none;
    transform: translateZ(0); /* 开启硬件加速 */
}

/* 页面过渡动画 */
body {
    opacity: 0;
    transition: opacity 0.5s ease;
}

body.loaded {
    opacity: 1;
}

/* 骨架屏加载动画 (简单版) */
.skeleton-loading {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s infinite;
    color: transparent !important;
    border-radius: 4px;
}

@keyframes skeleton-loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* 按钮微交互增强 */
.btn {
    position: relative;
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.btn:active {
    transform: scale(0.95);
}

/* 自定义动画 */
@keyframes float {
    0% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-10px);
    }
    100% {
        transform: translateY(0px);
    }
}

.float {
    animation: float 3s ease-in-out infinite;
}

/* 下载选项显示/隐藏 */
#windows-download,
#linux-download {
    display: none;
}

#windows-download.active,
#linux-download.active {
    display: block;
    animation: fadeIn 0.5s ease-in-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}