/* Global Styles */
/* ============= */

:root {
    --primary-color: #e74c3c;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --info-color: #17a2b8;
    --warning-color: #ffc107;
    --danger-color: #e74c3c;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --font-family: "Inter", sans-serif;
    --navbar-height: 70px;
}

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

body {
    font-family: var(--font-family);
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.5rem;
}

h2 {
    font-size: 2rem;
}

h3 {
    font-size: 1.75rem;
}

h4 {
    font-size: 1.5rem;
}

h5 {
    font-size: 1.25rem;
}

h6 {
    font-size: 1rem;
}

p {
    margin-bottom: 1rem;
    line-height: 1.6;
}

/* Links */
a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #c82333;
    text-decoration: none;
}

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

li {
    margin-bottom: 0.5rem;
}

/* Images */
img {
    max-width: 100%;
    height: auto;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Row and Columns */
.row {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -0.75rem;
}

.col, .col-1, .col-2, .col-3, .col-4, .col-5, .col-6, .col-7, .col-8, .col-9, .col-10, .col-11, .col-12,
.col-sm, .col-sm-1, .col-sm-2, .col-sm-3, .col-sm-4, .col-sm-5, .col-sm-6, .col-sm-7, .col-sm-8, .col-sm-9, .col-sm-10, .col-sm-11, .col-sm-12,
.col-md, .col-md-1, .col-md-2, .col-md-3, .col-md-4, .col-md-5, .col-md-6, .col-md-7, .col-md-8, .col-md-9, .col-md-10, .col-md-11, .col-md-12,
.col-lg, .col-lg-1, .col-lg-2, .col-lg-3, .col-lg-4, .col-lg-5, .col-lg-6, .col-lg-7, .col-lg-8, .col-lg-9, .col-lg-10, .col-lg-11, .col-lg-12,
.col-xl, .col-xl-1, .col-xl-2, .col-xl-3, .col-xl-4, .col-xl-5, .col-xl-6, .col-xl-7, .col-xl-8, .col-xl-9, .col-xl-10, .col-xl-11, .col-xl-12 {
    padding: 0 0.75rem;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

.text-primary {
    color: var(--primary-color) !important;
}

.text-secondary {
    color: var(--secondary-color) !important;
}

.text-success {
    color: var(--success-color) !important;
}

.text-danger {
    color: var(--danger-color) !important;
}

.text-warning {
    color: var(--warning-color) !important;
}

.text-info {
    color: var(--info-color) !important;
}

.text-light {
    color: var(--light-color) !important;
}

.text-dark {
    color: var(--dark-color) !important;
}

.text-muted {
    color: #6c757d !important;
}

.footer-links .text-muted:hover,
a.text-muted:hover {
    color: #e74c3c !important;
    transition: color 0.3s ease;
}

.bg-primary {
    background-color: var(--primary-color) !important;
}

.bg-secondary {
    background-color: var(--secondary-color) !important;
}

.bg-success {
    background-color: var(--success-color) !important;
}

.bg-danger {
    background-color: var(--danger-color) !important;
}

.bg-warning {
    background-color: var(--warning-color) !important;
}

.bg-info {
    background-color: var(--info-color) !important;
}

.bg-light {
    background-color: var(--light-color) !important;
}

.bg-dark {
    background-color: var(--dark-color) !important;
}

.bg-white {
    background-color: white !important;
}

/* Spacing */
.m-0 { margin: 0 !important; }
.m-1 { margin: 0.25rem !important; }
.m-2 { margin: 0.5rem !important; }
.m-3 { margin: 1rem !important; }
.m-4 { margin: 1.5rem !important; }
.m-5 { margin: 3rem !important; }

.mt-0 { margin-top: 0 !important; }
.mt-1 { margin-top: 0.25rem !important; }
.mt-2 { margin-top: 0.5rem !important; }
.mt-3 { margin-top: 1rem !important; }
.mt-4 { margin-top: 1.5rem !important; }
.mt-5 { margin-top: 3rem !important; }

.mb-0 { margin-bottom: 0 !important; }
.mb-1 { margin-bottom: 0.25rem !important; }
.mb-2 { margin-bottom: 0.5rem !important; }
.mb-3 { margin-bottom: 1rem !important; }
.mb-4 { margin-bottom: 1.5rem !important; }
.mb-5 { margin-bottom: 3rem !important; }

.p-0 { padding: 0 !important; }
.p-1 { padding: 0.25rem !important; }
.p-2 { padding: 0.5rem !important; }
.p-3 { padding: 1rem !important; }
.p-4 { padding: 1.5rem !important; }
.p-5 { padding: 3rem !important; }

.pt-0 { padding-top: 0 !important; }
.pt-1 { padding-top: 0.25rem !important; }
.pt-2 { padding-top: 0.5rem !important; }
.pt-3 { padding-top: 1rem !important; }
.pt-4 { padding-top: 1.5rem !important; }
.pt-5 { padding-top: 3rem !important; }

.pb-0 { padding-bottom: 0 !important; }
.pb-1 { padding-bottom: 0.25rem !important; }
.pb-2 { padding-bottom: 0.5rem !important; }
.pb-3 { padding-bottom: 1rem !important; }
.pb-4 { padding-bottom: 1.5rem !important; }
.pb-5 { padding-bottom: 3rem !important; }

/* Display */
.d-none { display: none !important; }
.d-block { display: block !important; }
.d-inline { display: inline !important; }
.d-inline-block { display: inline-block !important; }
.d-flex { display: flex !important; }
.d-inline-flex { display: inline-flex !important; }

/* Flexbox */
.flex-row { flex-direction: row !important; }
.flex-column { flex-direction: column !important; }
.flex-wrap { flex-wrap: wrap !important; }
.flex-nowrap { flex-wrap: nowrap !important; }
.justify-content-start { justify-content: flex-start !important; }
.justify-content-end { justify-content: flex-end !important; }
.justify-content-center { justify-content: center !important; }
.justify-content-between { justify-content: space-between !important; }
.justify-content-around { justify-content: space-around !important; }
.align-items-start { align-items: flex-start !important; }
.align-items-end { align-items: flex-end !important; }
.align-items-center { align-items: center !important; }
.align-items-baseline { align-items: baseline !important; }
.align-items-stretch { align-items: stretch !important; }

/* Position */
.position-relative { position: relative !important; }
.position-absolute { position: absolute !important; }
.position-fixed { position: fixed !important; }
.position-sticky { position: sticky !important; }

/* Border */
.border { border: 1px solid #dee2e6 !important; }
.border-0 { border: 0 !important; }
.border-top { border-top: 1px solid #dee2e6 !important; }
.border-bottom { border-bottom: 1px solid #dee2e6 !important; }
.border-left { border-left: 1px solid #dee2e6 !important; }
.border-right { border-right: 1px solid #dee2e6 !important; }

.rounded { border-radius: 0.375rem !important; }
.rounded-0 { border-radius: 0 !important; }
.rounded-1 { border-radius: 0.25rem !important; }
.rounded-2 { border-radius: 0.5rem !important; }
.rounded-3 { border-radius: 1rem !important; }
.rounded-circle { border-radius: 50% !important; }

/* Shadow */
.shadow { box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15) !important; }
.shadow-sm { box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075) !important; }
.shadow-lg { box-shadow: 0 1rem 3rem rgba(0, 0, 0, 0.175) !important; }
.shadow-none { box-shadow: none !important; }

/* Layout & Structure */
.main-content {
    padding-top: var(--navbar-height); /* Đảm bảo tất cả nội dung đều cách navbar */
}

@media (max-width: 768px) {
    :root {
        --navbar-height: 60px; /* Navbar thấp hơn trên thiết bị di động */
    }
}

/* Responsive Design */
@media (max-width: 576px) {
    .container {
        padding: 0 0.75rem;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.75rem;
    }
    
    h3 {
        font-size: 1.5rem;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }
}

@media (max-width: 992px) {
    .container {
        padding: 0 1.5rem;
    }
}

@media (max-width: 1200px) {
    .container {
        padding: 0 2rem;
    }
}

/* Print Styles */
@media print {
    .no-print {
        display: none !important;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.4;
    }
    
    h1, h2, h3, h4, h5, h6 {
        page-break-after: avoid;
    }
    
    .page-break {
        page-break-before: always;
    }
}

/* Accessibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.sr-only-focusable:active,
.sr-only-focusable:focus {
    position: static;
    width: auto;
    height: auto;
    overflow: visible;
    clip: auto;
    white-space: normal;
}

/* Focus Styles */
:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Selection */
::selection {
    background-color: var(--primary-color);
    color: white;
}

::-moz-selection {
    background-color: var(--primary-color);
    color: white;
}