:root {
    --income-color: #2ecc71;
    --expense-color: #e74c3c;
    --primary-bg: #f8f9fa;
    --secondary-bg: #f1f3f5;
    --border-color: #ddd;
}

* {
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
}

body {
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
}

h2, h3 {
    color: #2c3e50;
    margin-bottom: 20px;
}

h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 30px;
}

h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
}

/* 输入区域 */
.input-section, 
.filter-section, 
.stats-section, 
.records-section {
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.input-row {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 15px;
}

.input-group {
    flex: 1;
    min-width: 200px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: #555;
}

input, select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 16px;
}

input:focus, select:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52,152,219,0.2);
}

button {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: all 0.2s;
}

button:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn-add {
    background-color: var(--income-color);
    color: white;
}

.btn-filter {
    background-color: #3498db;
    color: white;
}

.btn-export {
    background-color: #9b59b6;
    color: white;
}

/* 统计区域 */
.stats-section {
    background: var(--secondary-bg);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 20px;
}

.stat-card {
    background: white;
    padding: 15px;
    border-radius: 6px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.stat-value {
    font-size: 24px;
    font-weight: bold;
    margin-top: 5px;
}

.income-text {
    color: var(--income-color);
}

.expense-text {
    color: var(--expense-color);
}

.category-stats {
    margin-top: 20px;
}

.category-stats h4 {
    margin-bottom: 10px;
}

.category-stat {
    margin-left: 20px;
    margin-bottom: 5px;
}

/* 记录列表 */
.record-item {
    display: flex;
    justify-content: space-between;
    padding: 15px;
    margin-bottom: 10px;
    background: var(--primary-bg);
    border-radius: 6px;
    transition: all 0.2s;
}

.record-item:hover {
    transform: translateX(5px);
    box-shadow: 0 3px 5px rgba(0,0,0,0.1);
}

.record-left {
    flex: 1;
}

.record-right {
    text-align: right;
    min-width: 150px;
}

.category-tag {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 14px;
    margin-right: 8px;
}

.income-bg {
    background-color: #d3f5d3;
    color: var(--income-color);
}

.expense-bg {
    background-color: #ffe5e5;
    color: var(--expense-color);
}

.record-remark {
    color: #666;
    margin: 5px 0;
    font-size: 14px;
}

.record-date {
    color: #888;
    font-size: 13px;
}

.delete-btn {
    color: #ff4444;
    margin-left: 15px;
    cursor: pointer;
    font-size: 14px;
}

/* 提示框 */
.alert {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 20px;
    border-radius: 4px;
    color: white;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.2);
    opacity: 1;
    transition: opacity 0.5s ease-out;
}

.alert-success {
    background-color: var(--income-color);
}

.alert-error {
    background-color: var(--expense-color);
}

/* 响应式调整 */
@media (max-width: 768px) {
    .input-row {
        flex-direction: column;
        gap: 10px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .record-item {
        flex-direction: column;
    }
    
    .record-right {
        text-align: left;
        margin-top: 10px;
    }
}