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

:root {
    --primary: #667eea;
    --secondary: #764ba2;
    --dark: #1a1a2e;
    --light: #f8f9fa;
    --gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--light);
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.header {
    background: white;
    padding: 20px 0;
    box-shadow: var(--shadow);
    margin-bottom: 40px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
}

.nav {
    display: flex;
    gap: 8px;
}

.nav a {
    padding: 10px 20px;
    color: #555;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s ease;
    font-weight: 500;
}

.nav a:hover,
.nav a.active {
    background: var(--gradient);
    color: white;
}

h1 {
    font-size: 32px;
    color: var(--dark);
    margin-bottom: 30px;
    font-weight: 700;
}

h2 {
    font-size: 22px;
    color: var(--dark);
    margin: 30px 0 20px;
    font-weight: 600;
    padding-bottom: 10px;
    border-bottom: 2px solid #eee;
}

.alert {
    padding: 16px 24px;
    border-radius: 12px;
    margin-bottom: 24px;
    font-weight: 500;
}

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

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

.btn {
    display: inline-block;
    padding: 12px 28px;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    cursor: pointer;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary {
    background: var(--gradient);
    color: white;
    box-shadow: 0 4px 20px rgba(102, 126, 234, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(102, 126, 234, 0.4);
}

.btn-danger {
    background: #dc3545;
    color: white;
}

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

.btn-small {
    padding: 6px 16px;
    font-size: 13px;
}

.btn-block {
    width: 100%;
}

.form-card {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 10px;
    font-weight: 600;
    color: #333;
    font-size: 14px;
}

.form-control {
    width: 100%;
    padding: 14px 18px;
    border: 2px solid #e9ecef;
    border-radius: 12px;
    font-size: 15px;
    font-family: inherit;
    transition: all 0.3s ease;
    background: #fafbfc;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    background: white;
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
}

.form-control::placeholder {
    color: #aaa;
}

textarea.form-control {
    resize: vertical;
    min-height: 120px;
}

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

.table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.table th,
.table td {
    padding: 16px;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.table th {
    background: var(--light);
    font-weight: 600;
    color: var(--dark);
}

.table tr:hover {
    background: var(--light);
}

.table tr:last-child td {
    border-bottom: none;
}

.actions {
    display: flex;
    gap: 8px;
}

.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
}

.stat-card {
    background: white;
    padding: 32px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.stat-number {
    font-size: 48px;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    color: #666;
    margin-top: 10px;
    font-size: 16px;
}

.footer {
    text-align: center;
    padding: 40px;
    color: #999;
    margin-top: 60px;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #999;
    background: white;
    border-radius: 20px;
    box-shadow: var(--shadow);
}

.empty-state .empty-icon {
    font-size: 64px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.avatar-upload {
    display: flex;
    align-items: center;
    gap: 24px;
    margin-bottom: 32px;
}

.avatar-preview {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    border: 4px solid #eee;
}

.avatar-preview img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.avatar-preview span {
    font-size: 48px;
    color: white;
}

.avatar-info {
    flex: 1;
}

.avatar-info p {
    margin-bottom: 12px;
    color: #666;
    font-size: 14px;
}

@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 16px;
    }

    .nav {
        flex-wrap: wrap;
        justify-content: center;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .form-card {
        padding: 24px;
    }

    .container {
        padding: 0 16px;
    }

    h1 {
        font-size: 24px;
    }

    .table {
        display: block;
        overflow-x: auto;
    }
}