/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background-color: var(--color-background);
    color: var(--color-on-surface);
    line-height: 1.5;
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

/* 内容容器 */
.content-container {
    max-width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    padding-bottom: 80px; /* 为底部导航栏留出空间 */
}

/* 毛玻璃背景 */
.blur-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('../assets/images/background.jpg');
    background-size: cover;
    background-position: center;
    filter: blur(var(--blur-amount));
    z-index: -1;
    opacity: 0.7;
}

/* 头部样式 */
.app-header {
    padding: var(--space-4);
    background-color: rgba(var(--color-surface), 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: var(--shadow-1);
    position: sticky;
    top: 0;
    z-index: 10;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}
.header-back{
    float:left;
    color:black;
    text-decoration:none;
    font-size:min(5vw,3vh);
}
.app-title {
    font-size: 1.5rem;
    font-weight: var(--font-weight-medium);
    color: var(--color-on-surface);
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
}
/* 主内容区 */
.main-content {
    flex: 1;
    padding: var(--space-4);
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* 卡片基础样式 */
.card {
    background-color: rgba(var(--color-surface), 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: var(--radius-large);
    padding: var(--space-4);
    margin-bottom: var(--space-4);
    box-shadow: var(--shadow-1);
    transition: transform var(--duration-medium) ease, box-shadow var(--duration-medium) ease;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-2);
}

.card-content {
    margin-bottom: var(--space-3);
}

.section-title {
    font-size: 1.1rem;
    font-weight: var(--font-weight-medium);
    margin-bottom: var(--space-3);
    color: var(--color-on-surface);
}

/* 底部导航栏 */
.bottom-navbar {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex;
    justify-content: space-around;
    background-color: rgba(var(--color-surface), 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: var(--space-2) 0;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
    z-index: 10;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: var(--color-on-surface-variant);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-full);
    transition: all var(--duration-medium) ease;
}

.nav-item i {
    font-size: 1.2rem;
    margin-bottom: var(--space-1);
}

.nav-item span {
    font-size: 0.75rem;
}

.nav-item.active {
    color: var(--color-primary);
    background-color: rgba(var(--color-primary), 0.1);
}

.nav-item:not(.active):hover {
    color: var(--color-on-surface);
    background-color: rgba(0,0,0,0.05);
}

/* 加载屏幕 */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--color-surface);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity var(--duration-long) ease, visibility var(--duration-long) ease;
}

.loading-animation {
    display: flex;
    margin-bottom: var(--space-4);
}

.loading-animation .circle {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: var(--color-primary);
    margin: 0 var(--space-2);
    animation: bounce 1.4s infinite ease-in-out;
}

.loading-animation .circle:nth-child(2) {
    animation-delay: 0.2s;
}

.loading-animation .circle:nth-child(3) {
    animation-delay: 0.4s;
}

.loading-text {
    color: var(--color-on-surface-variant);
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (min-width: 768px) {
    .main-content {
        padding: var(--space-5);
    }
    
    .app-header {
        padding: var(--space-4) var(--space-5);
    }
    
    .bottom-navbar {
        padding: var(--space-2) 0;
    }
    
    .nav-item {
        padding: var(--space-2) var(--space-4);
    }
}

@media (min-width: 1024px) {
    .main-content {
        display: grid;
        grid-template-columns: repeat(12, 1fr);
        gap: var(--space-4);
    }
    
    .welcome-card {
        grid-column: span 12;
    }
    
    .quick-access {
        grid-column: span 12;
    }
    
    .recent-activity {
        grid-column: span 12;
    }
}