/* Reset và Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: #fff;
    min-height: 100vh;
    box-shadow: 0 0 20px rgba(0,0,0,0.1);
}

/* Header */
.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1.5rem 1rem;
    text-align: center;
}

.header-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.header-subtitle {
    font-size: 1rem;
    opacity: 0.9;
    font-weight: 400;
}

/* Tab Navigation */
.tab-nav {
    background: #fff;
    border-bottom: 1px solid #e0e0e0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.tab-nav-container {
    display: flex;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.tab-nav-container::-webkit-scrollbar {
    display: none;
}

.tab-btn {
    flex: 1;
    min-width: 120px;
    padding: 1rem 0.5rem;
    border: none;
    background: transparent;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.8rem;
    color: #666;
    border-bottom: 3px solid transparent;
}

.tab-btn i {
    font-size: 1.2rem;
}

.tab-btn:hover {
    background: #f8f9fa;
    color: #667eea;
}

.tab-btn.active {
    color: #667eea;
    border-bottom-color: #667eea;
    background: #f8f9fa;
}

/* Content */
.content {
    padding: 0;
}

.tab-content {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.content-wrapper {
    padding: 1.5rem;
    max-width: 100%;
    overflow-x: auto;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    margin-bottom: 1rem;
    color: #2c3e50;
    font-weight: 600;
}

h1 { font-size: 1.8rem; }
h2 { font-size: 1.5rem; color: #667eea; }
h3 { font-size: 1.3rem; }
h4 { font-size: 1.1rem; }

p {
    margin-bottom: 1rem;
    line-height: 1.7;
}

ul, ol {
    margin-bottom: 1rem;
    padding-left: 1.5rem;
}

li {
    margin-bottom: 0.5rem;
}

strong {
    color: #2c3e50;
    font-weight: 600;
}

/* Cards and Sections */
.section {
    background: #fff;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    border-left: 4px solid #667eea;
}

.highlight-box {
    background: linear-gradient(135deg, #667eea10, #764ba210);
    border: 1px solid #667eea30;
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
}

.warning-box {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
    border-left: 4px solid #f39c12;
}

.success-box {
    background: #d4edda;
    border: 1px solid #c3e6cb;
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
    border-left: 4px solid #28a745;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #e0e0e0;
}

th {
    background: #667eea;
    color: white;
    font-weight: 600;
}

tr:hover {
    background: #f8f9fa;
}

/* Footer */
.footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 1.5rem;
    margin-top: 2rem;
}

/* Mobile Optimizations */
@media (max-width: 768px) {
    .header-title {
        font-size: 1.5rem;
    }
    
    .tab-btn {
        min-width: 100px;
        padding: 0.8rem 0.3rem;
        font-size: 0.7rem;
    }
    
    .tab-btn span {
        display: none;
    }
    
    .content-wrapper {
        padding: 1rem;
    }
    
    h1 { font-size: 1.5rem; }
    h2 { font-size: 1.3rem; }
    h3 { font-size: 1.1rem; }
    
    table {
        font-size: 0.9rem;
    }
    
    th, td {
        padding: 0.5rem;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 1rem 0.5rem;
    }
    
    .content-wrapper {
        padding: 0.75rem;
    }
    
    .section {
        padding: 1rem;
        margin-bottom: 1rem;
    }
    
    table {
        font-size: 0.8rem;
    }
    
    th, td {
        padding: 0.4rem;
    }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #667eea;
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: #5a6fd8;
}