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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: rgba(255, 255, 255, 0.95);
    padding: 20px 30px;
    border-radius: 15px;
    margin-bottom: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

header h1 {
    color: #333;
    font-size: 24px;
    margin-bottom: 15px;
}

header nav {
    display: flex;
    gap: 20px;
    flex-wrap: nowrap;
}

header nav a {
    text-decoration: none;
    color: #666;
    padding: 8px 16px;
    border-radius: 8px;
    transition: all 0.3s;
    white-space: nowrap;
    flex-shrink: 0;
}

header nav a:hover,
header nav a.active {
    background: #667eea;
    color: white;
}

.hero {
    background: rgba(255, 255, 255, 0.95);
    padding: 60px 40px;
    border-radius: 20px;
    text-align: center;
    margin-bottom: 40px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.hero h2 {
    font-size: 36px;
    color: #333;
    margin-bottom: 15px;
}

.hero p {
    color: #666;
    font-size: 18px;
    margin-bottom: 30px;
}

.btn-primary {
    display: inline-block;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 15px 40px;
    border-radius: 30px;
    text-decoration: none;
    font-size: 18px;
    font-weight: bold;
    transition: transform 0.3s, box-shadow 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    display: inline-block;
    background: #28a745;
    color: white;
    padding: 12px 30px;
    border-radius: 25px;
    text-decoration: none;
    font-size: 16px;
    transition: all 0.3s;
}

.btn-secondary:hover {
    background: #218838;
    transform: translateY(-2px);
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.feature-card {
    background: rgba(255, 255, 255, 0.95);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.feature-card h3 {
    color: #333;
    margin-bottom: 10px;
    font-size: 20px;
}

.feature-card p {
    color: #666;
}

.form-container {
    background: rgba(255, 255, 255, 0.95);
    padding: 40px;
    border-radius: 20px;
    max-width: 800px;
    margin: 0 auto;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.form-container h2 {
    color: #333;
    margin-bottom: 30px;
    text-align: center;
}

.form-container h3 {
    color: #667eea;
    margin: 25px 0 15px;
    font-size: 18px;
}

.form-group {
    margin-bottom: 20px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group label {
    display: block;
    color: #333;
    font-weight: 500;
    margin-bottom: 8px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
}

.payment-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
    padding: 30px;
    background: #f8f9fa;
    border-radius: 15px;
    align-items: center;
}

.qr-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    max-width: 400px;
    margin: 0 auto;
}

.qr-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
    justify-content: center;
    width: 100%;
}

.qr-tab {
    padding: 12px 20px;
    border: 2px solid #667eea;
    background: white;
    color: #667eea;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s;
    flex: 1;
    max-width: 150px;
    text-align: center;
}

.qr-tab:hover,
.qr-tab.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: transparent;
}

.qr-code {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.qr-code img {
    width: 200px;
    height: 200px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.qr-code p {
    margin-top: 15px;
    color: #333;
    font-size: 16px;
}

.qr-code p strong {
    color: #e74c3c;
    font-size: 20px;
}

.upload-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 300px;
}

.upload-section input[type="file"] {
    padding: 7px 10px;
    border: 2px dashed #667eea;
    border-radius: 8px;
    background: white;
    cursor: pointer;
    font-size: 13px;
    height: 44px;
    width: 100%;
}

.hint {
    color: #999;
    font-size: 14px;
    margin-top: 10px;
}

.alert {
    padding: 15px 20px;
    border-radius: 10px;
    margin-bottom: 20px;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.admin-container {
    background: rgba(255, 255, 255, 0.95);
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.admin-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

.admin-header h2 {
    color: #333;
}

.stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 25px;
    border-radius: 15px;
    text-align: center;
}

.stat-card .stat-number {
    display: block;
    font-size: 32px;
    font-weight: bold;
}

.stat-card .stat-label {
    font-size: 14px;
    opacity: 0.9;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
    min-width: 900px;
}

.data-table-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.data-table th,
.data-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #e0e0e0;
    white-space: nowrap;
}

.data-table th {
    background: #f8f9fa;
    color: #333;
    font-weight: 600;
    position: sticky;
    top: 0;
    z-index: 10;
}

.data-table tr:hover {
    background: #f8f9fa;
}

.status-badge {
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
}

.status-paid {
    background: #d4edda;
    color: #155724;
}

.status-pending {
    background: #fff3cd;
    color: #856404;
}

@media (max-width: 768px) {
    .form-row,
    .payment-section,
    .stats {
        grid-template-columns: 1fr;
    }
    
    .payment-section {
        padding: 20px !important;
    }
    
    .qr-area {
        margin-bottom: 20px;
    }
    
    .qr-tabs {
        flex-direction: column;
        width: 100%;
    }
    
    .qr-tab {
        width: 100%;
    }
    
    .admin-header {
        flex-direction: column;
        gap: 15px;
    }
    
    header nav {
        flex-wrap: nowrap;
        justify-content: center;
    }
    
    header nav a {
        font-size: 14px;
        padding: 6px 12px;
    }
    
    .admin-actions {
        flex-wrap: nowrap;
        justify-content: center;
    }
    
    .data-table-wrapper {
        font-size: 13px;
    }
    
    .data-table th,
    .data-table td {
        padding: 10px 6px;
    }
    
    .login-container {
        padding: 20px !important;
    }
}
    
    .login-container {
        padding: 20px !important;
    }
}

/* 登录页面样式 */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 60vh;
}

.login-box {
    background: rgba(255, 255, 255, 0.95);
    padding: 40px;
    border-radius: 20px;
    width: 100%;
    max-width: 400px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.login-box h2 {
    text-align: center;
    margin-bottom: 30px;
    color: #333;
}

.login-hint {
    text-align: center;
    color: #999;
    font-size: 14px;
    margin-top: 20px;
}

.btn-logout {
    background: #dc3545;
    color: white;
    padding: 8px 20px;
    border-radius: 20px;
    text-decoration: none;
    font-size: 14px;
    transition: all 0.3s;
}

.btn-logout:hover {
    background: #c82333;
}

.admin-actions {
    display: flex;
    gap: 10px;
    align-items: center;
}

.login-status {
    color: #667eea;
    font-weight: 500;
}

.alert-error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* 系统二维码样式 */
.qrcode-section {
    background: rgba(255, 255, 255, 0.95);
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    margin-top: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.qrcode-section h3 {
    color: #333;
    margin-bottom: 20px;
}

.system-qrcode {
    width: 200px;
    height: 200px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.qrcode-section p {
    margin-top: 15px;
    color: #666;
}