@import url('https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap');
* {
    font-family: 'Roboto', sans-serif;
    font-size: 15px;
}
html {
    scroll-behavior: smooth;
}
/* Container and Base Styles */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}
.wrapper-content {
    background-color: #fdfdfd;
    padding: 30px;
    border-radius: 8px;
    line-height: 1.6;
}
/* Title Styles */
.title-center {
    text-align: center;
    font-size: 24px;
    font-weight: 700;
    color: #2c3e50;
    margin-bottom: 30px;
    padding: 20px 0;
    border-bottom: 3px solid #3498db;
}
/* Section Styles */
.section {
    margin: 25px 0;
    padding: 20px;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 8px;
    border-left: 4px solid #3498db;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
}
.section-title {
    font-size: 18px;
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.section-number {
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    padding: 8px 12px;
    border-radius: 20px;
    font-weight: 700;
    min-width: 40px;
    text-align: center;
}
/* Ordered List Styles */
ol {
    counter-reset: item;
    padding-left: 0;
    margin: 15px 0;
}
ol>li {
    display: block;
    margin: 12px 0;
    padding: 15px 20px;
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    border-radius: 8px;
    border-left: 3px solid #3498db;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    position: relative;
    transition: all 0.3s ease;
}
ol>li:hover {
    transform: translateX(5px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}
ol>li::before {
    content: counter(item, decimal) ".";
    counter-increment: item;
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    font-weight: 700;
    border-radius: 50%;
    width: 25px;
    height: 25px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: absolute;
    left: -12px;
    top: 11px;
    font-size: 12px;
}
/* Nested Ordered Lists (Level 2) */
ol ol {
    counter-reset: subitem;
    margin: 10px 0 10px 20px;
    padding-left: 0;
}
ol ol>li {
    background: linear-gradient(135deg, #ecf0f1 0%, #bdc3c7 100%);
    border-left: 3px solid #95a5a6;
    margin: 8px 0;
    padding: 12px 18px;
}
ol ol>li::before {
    content: counter(subitem, lower-alpha) ".";
    counter-increment: subitem;
    background: linear-gradient(135deg, #95a5a6 0%, #7f8c8d 100%);
    width: 22px;
    height: 22px;
    font-size: 11px;
}
/* Nested Ordered Lists (Level 3) */
ol ol ol {
    counter-reset: subsubitem;
}
ol ol ol>li {
    background: linear-gradient(135deg, #f4f4f4 0%, #e8e8e8 100%);
    border-left: 3px solid #bdc3c7;
    margin: 6px 0;
    padding: 10px 16px;
}
ol ol ol>li::before {
    content: counter(subsubitem, lower-roman) ".";
    counter-increment: subsubitem;
    background: linear-gradient(135deg, #bdc3c7 0%, #95a5a6 100%);
    width: 20px;
    height: 20px;
    font-size: 10px;
}
/* Unordered List Styles */
ul {
    padding-left: 0;
    margin: 15px 0;
}
ul>li {
    display: block;
    margin: 10px 0;
    padding: 12px 20px;
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    border-radius: 8px;
    border-left: 3px solid #e74c3c;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    position: relative;
    transition: all 0.3s ease;
}
ul>li:hover {
    transform: translateX(5px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}
ul>li::before {
    content: "●";
    color: #e74c3c;
    font-size: 16px;
    position: absolute;
    left: -10px;
    top: 12px;
    background: white;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}
/* Nested Unordered Lists (Level 2) */
ul ul {
    margin: 8px 0 8px 20px;
}
ul ul>li {
    background: linear-gradient(135deg, #fdf2e9 0%, #f39c12 100%);
    border-left: 3px solid #f39c12;
    margin: 6px 0;
    padding: 10px 16px;
}
ul ul>li::before {
    content: "○";
    color: #f39c12;
    font-size: 14px;
}
/* Nested Unordered Lists (Level 3) */
ul ul ul>li {
    background: linear-gradient(135deg, #f8f9fa 0%, #dee2e6 100%);
    border-left: 3px solid #6c757d;
    margin: 4px 0;
    padding: 8px 14px;
}
ul ul ul>li::before {
    content: "▪";
    color: #6c757d;
    font-size: 12px;
}
/* Mixed Nested Lists */
ol ul,
ul ol {
    margin: 10px 0 10px 20px;
}
/* Text Content Styles */
li {
    font-size: 14px;
    line-height: 1.6;
    color: #2c3e50;
}
li strong,
.bold-text {
    color: #2c3e50;
    font-weight: 600;
}
li em {
    color: #7f8c8d;
    font-style: italic;
}
/* Special Classes */
.highlight-item {
    background: linear-gradient(135deg, #fff3cd 0%, #ffeaa7 100%) !important;
    border-left: 3px solid #f39c12 !important;
}
.important-item {
    background: linear-gradient(135deg, #f8d7da 0%, #f5c6cb 100%) !important;
    border-left: 3px solid #e74c3c !important;
}
.note-item {
    background: linear-gradient(135deg, #d1ecf1 0%, #bee5eb 100%) !important;
    border-left: 3px solid #17a2b8 !important;
}
/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
        margin: 10px;
    }
    .wrapper-content {
        padding: 20px;
    }
    .title-center {
        font-size: 20px;
        padding: 15px 0;
    }
    .section {
        padding: 15px;
        margin: 15px 0;
    }
    .section-title {
        font-size: 16px;
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
    }
    .section-number {
        padding: 6px 10px;
        font-size: 12px;
    }
    ol>li,
    ul>li {
        padding: 10px 15px;
        margin: 8px 0;
    }
    ol>li::before {
        width: 20px;
        height: 20px;
        font-size: 10px;
        left: -10px;
        top: 10px;
    }
    ol ol,
    ul ul {
        margin-left: 15px;
    }
    ol ol>li,
    ul ul>li {
        padding: 8px 12px;
        margin: 6px 0;
    }
    ol ol ol>li,
    ul ul ul>li {
        padding: 6px 10px;
        margin: 4px 0;
    }
    li {
        font-size: 13px;
    }
}
@media (max-width: 480px) {
    .container {
        padding: 10px;
        margin: 5px;
    }
    .wrapper-content {
        padding: 15px;
    }
    .title-center {
        font-size: 18px;
    }
    .section {
        padding: 12px;
    }
    ol>li,
    ul>li {
        padding: 8px 12px;
    }
    li {
        font-size: 12px;
        line-height: 1.5;
    }
}
/* Print Styles */
@media print {
    .container {
        box-shadow: none;
        padding: 0;
        max-width: none;
    }
    .wrapper-content {
        box-shadow: none;
        padding: 10px;
    }
    .section {
        box-shadow: none;
        border: 1px solid #ccc;
        break-inside: avoid;
    }
    ol>li,
    ul>li {
        box-shadow: none;
        border: 1px solid #eee;
        break-inside: avoid;
    }
    ol>li:hover,
    ul>li:hover {
        transform: none;
    }
    #scrollToTopBtn {
        display: none !important;
    }
    .section-number {
        background: #333 !important;
        color: white !important;
    }
    ol>li::before {
        background: #333 !important;
        color: white !important;
    }
}
/* Animation for smooth interactions */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}
.section {
    animation: slideIn 0.5s ease-out;
}
/* Additional utility classes */
.text-highlight {
    background: linear-gradient(135deg, #fff3cd 0%, #ffeaa7 100%);
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 500;
}
.text-danger {
    color: #e74c3c !important;
    font-weight: 600;
}
.text-success {
    color: #27ae60 !important;
    font-weight: 600;
}
.text-info {
    color: #3498db !important;
    font-weight: 600;
}
/* Scroll to top button */
#scrollToTopBtn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 50px;
    padding: 12px 20px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    display: none;
    align-items: center;
    gap: 8px;
    transition: all 0.3s ease;
    z-index: 1000;
    font-family: inherit;
}
#scrollToTopBtn:hover {
    background: linear-gradient(135deg, #764ba2 0%, #667eea 100%);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}
#scrollToTopBtn:active {
    transform: translateY(0);
}
#scrollToTopBtn svg {
    transition: transform 0.3s ease;
}
#scrollToTopBtn:hover svg {
    transform: translateY(-2px);
}
/* Responsive design */
@media (max-width: 768px) {
    #scrollToTopBtn {
        bottom: 20px;
        right: 20px;
        padding: 10px 16px;
        font-size: 12px;
    }
    #scrollToTopBtn span {
        display: none;
    }
}
/* Animation cho việc xuất hiện */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
#scrollToTopBtn.show {
    display: flex !important;
    animation: fadeInUp 0.3s ease;
}