/* PDF救星 - 科幻帅气主题 */
:root {
    /* 科幻色彩系统 */
    --sci-fi-primary: #0a0a2a;
    --sci-fi-secondary: #1a1a3a;
    --sci-fi-accent: #00d4ff;
    --sci-fi-accent-glow: rgba(0, 212, 255, 0.5);
    --sci-fi-danger: #ff2a6d;
    --sci-fi-success: #05d9e8;
    --sci-fi-warning: #ffcc00;
    --sci-fi-text: #ffffff;
    --sci-fi-text-secondary: #b0b0d0;
    --sci-fi-border: rgba(0, 212, 255, 0.2);
    --sci-fi-bg: linear-gradient(135deg, #0a0a2a 0%, #1a1a3a 100%);
    --sci-fi-card-bg: rgba(26, 26, 58, 0.8);
    --sci-fi-glow: 0 0 20px rgba(0, 212, 255, 0.3);
    
    /* 科幻字体 */
    --sci-fi-font-heading: 'Orbitron', 'Segoe UI', sans-serif;
    --sci-fi-font-body: 'Exo 2', 'Segoe UI', sans-serif;
    
    /* 科幻动画 */
    --sci-fi-pulse: pulse 2s infinite;
    --sci-fi-glow-animation: glow 3s infinite alternate;
    --sci-fi-scan: scan 4s linear infinite;
}

/* 科幻导航栏 */
.sci-fi-nav {
    background: var(--sci-fi-primary);
    border-bottom: 1px solid var(--sci-fi-border);
    box-shadow: 0 0 30px rgba(0, 212, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.sci-fi-nav::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--sci-fi-accent), transparent);
    animation: var(--sci-fi-scan);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

/* Logo样式 */
.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: all 0.3s ease;
}

.logo-wrapper:hover {
    transform: translateY(-2px);
}

.logo-icon {
    font-size: 2.5rem;
    animation: var(--sci-fi-pulse);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-family: var(--sci-fi-font-heading);
    font-size: 1.8rem;
    font-weight: 900;
    background: linear-gradient(90deg, var(--sci-fi-accent), var(--sci-fi-success));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.logo-subtitle {
    font-family: var(--sci-fi-font-body);
    font-size: 0.8rem;
    color: var(--sci-fi-text-secondary);
    letter-spacing: 3px;
    text-transform: uppercase;
}

/* 主导航 */
.nav-main {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--sci-fi-text);
    text-decoration: none;
    font-family: var(--sci-fi-font-body);
    font-weight: 500;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.nav-link::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 212, 255, 0.1), transparent);
    transition: left 0.5s ease;
}

.nav-link:hover::before {
    left: 100%;
}

.nav-link:hover {
    background: rgba(0, 212, 255, 0.1);
    color: var(--sci-fi-accent);
    box-shadow: var(--sci-fi-glow);
}

.nav-link.active {
    background: rgba(0, 212, 255, 0.15);
    color: var(--sci-fi-accent);
    box-shadow: var(--sci-fi-glow);
}

.nav-link i {
    font-size: 1.1rem;
}

/* 下拉菜单 */
.nav-dropdown {
    position: relative;
}

.dropdown-arrow {
    font-size: 0.8rem;
    margin-left: 0.25rem;
    transition: transform 0.3s ease;
}

.nav-dropdown:hover .dropdown-arrow {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    width: 320px;
    background: var(--sci-fi-card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--sci-fi-border);
    border-radius: 12px;
    padding: 1rem;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3), var(--sci-fi-glow);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s ease;
    z-index: 1000;
}

.nav-dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-section {
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--sci-fi-border);
}

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

.dropdown-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--sci-fi-accent);
    font-family: var(--sci-fi-font-heading);
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.75rem;
    padding: 0.25rem 0;
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--sci-fi-text);
    text-decoration: none;
    padding: 0.75rem 1rem;
    border-radius: 6px;
    transition: all 0.2s ease;
    font-family: var(--sci-fi-font-body);
}

.dropdown-item:hover {
    background: rgba(0, 212, 255, 0.1);
    color: var(--sci-fi-accent);
    transform: translateX(5px);
}

.dropdown-item i {
    width: 20px;
    text-align: center;
    font-size: 1rem;
}

/* 用户区域 */
.nav-user {
    display: flex;
    align-items: center;
}

.btn-sci-fi {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: linear-gradient(90deg, var(--sci-fi-accent), var(--sci-fi-success));
    color: var(--sci-fi-primary);
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-family: var(--sci-fi-font-heading);
    font-weight: 700;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.btn-sci-fi::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.btn-sci-fi:hover::before {
    left: 100%;
}

.btn-sci-fi:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 212, 255, 0.3);
}

.btn-sci-fi:active {
    transform: translateY(0);
}

/* 科幻动画 */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.8;
        transform: scale(1.05);
    }
}

@keyframes glow {
    0% {
        box-shadow: 0 0 10px rgba(0, 212, 255, 0.3);
    }
    100% {
        box-shadow: 0 0 20px rgba(0, 212, 255, 0.6), 0 0 30px rgba(0, 212, 255, 0.3);
    }
}

@keyframes scan {
    0% {
        left: -100%;
    }
    100% {
        left: 100%;
    }
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .nav-container {
        padding: 1rem;
    }
    
    .nav-main {
        gap: 1rem;
    }
    
    .nav-link {
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }
    
    .dropdown-menu {
        width: 280px;
    }
}

@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-main {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .dropdown-menu {
        position: fixed;
        top: auto;
        left: 50%;
        transform: translateX(-50%) translateY(10px);
        width: 90vw;
        max-width: 400px;
    }
}

/* 科幻全局样式 */
body {
    font-family: var(--sci-fi-font-body);
    color: var(--sci-fi-text);
    background: var(--sci-fi-bg);
    min-height: 100vh;
    margin: 0;
    padding: 0;
    overflow-x: hidden;
}

/* 科幻容器 */
.sci-fi-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

/* 科幻卡片 */
.sci-fi-card {
    background: var(--sci-fi-card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--sci-fi-border);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--sci-fi-glow);
    transition: all 0.3s ease;
}

.sci-fi-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4), var(--sci-fi-glow);
}

/* 科幻按钮 */
.sci-fi-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(0, 212, 255, 0.1);
    color: var(--sci-fi-accent);
    border: 1px solid var(--sci-fi-accent);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-family: var(--sci-fi-font-body);
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.sci-fi-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 212, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.sci-fi-btn:hover::before {
    left: 100%;
}

.sci-fi-btn:hover {
    background: rgba(0, 212, 255, 0.2);
    box-shadow: var(--sci-fi-glow);
    transform: translateY(-2px);
}

.sci-fi-btn-primary {
    background: linear-gradient(90deg, var(--sci-fi-accent), var(--sci-fi-success));
    color: var(--sci-fi-primary);
    border: none;
    font-weight: 700;
}

.sci-fi-btn-primary:hover {
    background: linear-gradient(90deg, var(--sci-fi-success), var(--sci-fi-accent));
}

/* 科幻英雄区域 */
.sci-fi-hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.sci-fi-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 30% 30%, rgba(0, 212, 255, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 70% 70%, rgba(5, 217, 232, 0.1) 0%, transparent 50%);
    animation: var(--sci-fi-glow-animation);
}

.hero-title {
    font-family: var(--sci-fi-font-heading);
    font-size: 4rem;
    font-weight: 900;
    background: linear-gradient(90deg, var(--sci-fi-accent), var(--sci-fi-success), var(--sci-fi-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-size: 200% auto;
    animation: gradient-shift 3s ease infinite;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.hero-subtitle {
    font-family: var(--sci-fi-font-body);
    font-size: 1.5rem;
    color: var(--sci-fi-text-secondary);
    max-width: 800px;
    margin: 0 auto 2rem;
    line-height: 1.6;
}

@keyframes gradient-shift {
    0%, 100% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
}

/* 科幻工具网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.tool-card {
    background: var(--sci-fi-card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--sci-fi-border);
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 212, 255, 0.05), transparent);
    transition: left 0.6s ease;
}

.tool-card:hover::before {
    left: 100%;
}

.tool-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4), var(--sci-fi-glow);
    border-color: var(--sci-fi-accent);
}

.tool-icon {
    font-size: 3rem;
    color: var(--sci-fi-accent);
    margin-bottom: 1rem;
    animation: var(--sci-fi-pulse);
}

.tool-title {
    font-family: var(--sci-fi-font-heading);
    font-size: 1.5rem;
    color: var(--sci-fi-text);
    margin-bottom: 1rem;
}

.tool-description {
    color: var(--sci-fi-text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

/* 科幻页脚 */
.sci-fi-footer {
    background: rgba(10, 10, 42, 0.9);
    border-top: 1px solid var(--sci-fi-border);
    padding: 3rem 0;
    margin-top: 4rem;
    position: relative;
}

.sci-fi-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--sci-fi-accent), transparent);
    animation: var(--sci-fi-scan);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;