:root {
    --primary-color: #333;
    --secondary-color: #666;
    --bg-color: #f5f5f7; /* 类苹果的浅灰背景 */
    --card-bg: #ffffff;
    --accent-color: #007aff;
    --success-color: #34c759;
    --pending-color: #ff9500;
    --progress-color: #007aff;
    --closed-color: #8e8e93;
    --border-radius: 12px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--primary-color);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Glass Header */
.glass-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    background: rgba(255, 255, 255, 0.75); /* 半透明白色 */
    backdrop-filter: blur(20px) saturate(180%); /* 高斯模糊 + 饱和度提升 */
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05); /* 极淡的分割线 */
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header-content {
    width: 100%;
    max-width: 800px;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-content h1 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

.header-content p {
    font-size: 0.875rem;
    color: var(--secondary-color);
}

/* Main Content */
main {
    padding-top: 100px; /* Header height + spacing */
    padding-bottom: 50px;
    min-height: 100vh;
    display: flex;
    justify-content: center;
}

.container {
    width: 100%;
    max-width: 800px;
    padding: 0 20px;
}

/* Todo List */
.todo-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.todo-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 20px 24px;
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    border: 1px solid rgba(0,0,0,0.02);
}

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

.todo-content {
    flex: 1;
}

.todo-text {
    font-size: 1rem;
    color: var(--primary-color);
    margin-bottom: 6px;
    font-weight: 500;
}

.todo-meta {
    font-size: 0.8rem;
    color: var(--secondary-color);
    display: flex;
    gap: 10px;
    align-items: center;
}

.collection-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.icon {
    opacity: 0.7;
    position: relative;
    top: -1px; /* 微调垂直对齐 */
}

.tag {
    background: #f0f0f5;
    padding: 2px 8px;
    border-radius: 6px;
    font-size: 0.75rem;
    color: #666;
}

/* Status Indicator */
.status-indicator {
    display: flex;
    align-items: center;
    margin-left: 20px;
}

.copy-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    margin-left: 12px;
    color: var(--secondary-color);
    padding: 6px;
    border-radius: 6px;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.copy-btn:hover {
    background-color: rgba(0, 0, 0, 0.05);
    color: var(--primary-color);
}

.copy-btn:active {
    background-color: rgba(0, 0, 0, 0.1);
    transform: scale(0.95);
}

.status-badge {
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-badge.completed {
    background: rgba(52, 199, 89, 0.15);
    color: var(--success-color);
}

.status-badge.pending {
    background: rgba(255, 149, 0, 0.15);
    color: var(--pending-color);
}

.status-badge.in_progress {
    background: rgba(0, 122, 255, 0.15);
    color: var(--progress-color);
}

.status-badge.closed {
    background: rgba(142, 142, 147, 0.15);
    color: var(--closed-color);
}

/* Completed items style */
.todo-card.is-completed .todo-text {
    text-decoration: line-through;
    color: #999;
}

.loading {
    text-align: center;
    color: var(--secondary-color);
    padding: 40px;
}

footer {
    text-align: center;
    padding: 20px;
    color: #999;
    font-size: 0.8rem;
}

/* 响应式调整 */
@media (max-width: 600px) {
    .todo-card {
        padding: 16px;
    }
    
    .status-badge {
        padding: 4px 8px;
        font-size: 0.7rem;
    }
}