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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    background: linear-gradient(135deg, rgb(240, 248, 255) 0%, rgb(230, 240, 250) 100%);
    color: rgb(30, 30, 30);
}

.container {
    display: block;
    max-width: 1400px;
    margin: 0 auto;
    min-height: 100vh;
    padding: 20px;
}

/* Header */
.header {
    background: linear-gradient(135deg, rgb(45, 85, 135) 0%, rgb(65, 105, 165) 100%);
    color: rgb(255, 255, 255);
    padding: 30px;
    border-radius: 15px;
    margin-bottom: 30px;
    border: 4px solid rgb(25, 55, 95);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
}

.header-content {
    text-align: center;
    margin-bottom: 30px;
}

.header-content h1 {
    font-size: 36px;
    font-weight: bold;
    margin-bottom: 10px;
    text-shadow: 3px 3px 6px rgba(0, 0, 0, 0.3);
}

.subtitle {
    font-size: 18px;
    font-weight: bold;
    color: rgb(255, 215, 100);
}

/* Navigation Box in Header */
.navigation-box {
    background: linear-gradient(135deg, rgb(255, 255, 255) 0%, rgb(245, 250, 255) 100%);
    border: 4px solid rgb(255, 200, 50);
    border-radius: 15px;
    padding: 25px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.nav-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 4px solid rgb(255, 160, 0);
}

.nav-header h2 {
    font-size: 26px;
    font-weight: bold;
    color: rgb(25, 55, 95);
    margin: 0;
}

.print-btn-header {
    padding: 12px 25px;
    background: linear-gradient(135deg, rgb(76, 175, 80) 0%, rgb(56, 142, 60) 100%);
    color: rgb(255, 255, 255);
    border: 3px solid rgb(200, 255, 200);
    border-radius: 10px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.print-btn-header:hover {
    background: linear-gradient(135deg, rgb(56, 142, 60) 0%, rgb(46, 125, 50) 100%);
    transform: scale(1.05);
    box-shadow: 0 6px 15px rgba(76, 175, 80, 0.5);
}

.nav-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
}

.nav-link {
    display: block;
    color: rgb(255, 255, 255);
    text-decoration: none;
    padding: 14px 18px;
    border-radius: 10px;
    font-weight: bold;
    font-size: 15px;
    text-align: center;
    transition: all 0.3s ease;
    background: linear-gradient(135deg, rgb(45, 85, 135) 0%, rgb(35, 75, 125) 100%);
    border: 3px solid rgb(65, 105, 165);
    box-shadow: 0 3px 8px rgba(0, 0, 0, 0.2);
}

.nav-link:hover {
    background: linear-gradient(135deg, rgb(255, 160, 0) 0%, rgb(255, 140, 0) 100%);
    border-color: rgb(255, 220, 100);
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(255, 140, 0, 0.5);
    color: rgb(255, 255, 255);
}

/* Main Content */
.main-content {
    margin: 0;
    padding: 0;
}

/* Content Sections */
.content-section {
    background: rgb(255, 255, 255);
    padding: 30px;
    margin-bottom: 30px;
    border-radius: 15px;
    border: 3px solid rgb(65, 105, 155);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.1);
}

.content-section h2 {
    font-size: 28px;
    font-weight: bold;
    color: rgb(25, 55, 95);
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 4px solid rgb(255, 140, 0);
}

.content-section h3 {
    font-size: 22px;
    font-weight: bold;
    color: rgb(35, 75, 125);
    margin-top: 25px;
    margin-bottom: 15px;
}

.content-section h4 {
    font-size: 18px;
    font-weight: bold;
    color: rgb(45, 85, 135);
    margin-top: 15px;
    margin-bottom: 10px;
}

.content-section p {
    font-size: 16px;
    font-weight: bold;
    line-height: 1.8;
    margin-bottom: 15px;
    color: rgb(30, 30, 30);
}

.content-section ul, .content-section ol {
    margin-left: 30px;
    margin-bottom: 15px;
}

.content-section li {
    font-size: 15px;
    font-weight: bold;
    margin-bottom: 8px;
    color: rgb(30, 30, 30);
}

.subsection {
    margin-top: 25px;
    padding-top: 20px;
    border-top: 2px dashed rgb(180, 180, 180);
}

/* Info Box */
.info-box {
    background: linear-gradient(135deg, rgb(230, 245, 255) 0%, rgb(215, 235, 250) 100%);
    border: 3px solid rgb(65, 105, 155);
    border-left: 8px solid rgb(45, 85, 135);
    padding: 20px;
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.info-box h3, .info-box h4 {
    color: rgb(25, 55, 95);
    font-weight: bold;
    margin-bottom: 10px;
}

.info-box ul {
    margin-left: 20px;
}

.info-box li {
    font-weight: bold;
    color: rgb(30, 30, 30);
}

/* Formula Box */
.formula-box {
    background: linear-gradient(135deg, rgb(255, 245, 230) 0%, rgb(255, 235, 210) 100%);
    border: 3px solid rgb(255, 140, 0);
    border-left: 8px solid rgb(230, 115, 0);
    padding: 20px;
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.formula-box h4 {
    color: rgb(180, 90, 0);
    font-weight: bold;
    margin-bottom: 10px;
}

.formula-box p, .formula-box ul, .formula-box li {
    font-weight: bold;
    color: rgb(30, 30, 30);
}

.formula-text {
    font-size: 17px;
    font-weight: bold;
    color: rgb(180, 90, 0);
    background: rgb(255, 250, 240);
    padding: 10px;
    border-left: 5px solid rgb(255, 140, 0);
    margin: 10px 0;
}

/* Tables */
.info-table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: rgb(255, 255, 255);
    border: 3px solid rgb(65, 105, 155);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.info-table thead {
    background: linear-gradient(135deg, rgb(45, 85, 135) 0%, rgb(65, 105, 165) 100%);
    color: rgb(255, 255, 255);
}

.info-table th {
    padding: 15px;
    text-align: left;
    font-weight: bold;
    font-size: 15px;
    border: 2px solid rgb(25, 55, 95);
}

.info-table td {
    padding: 12px 15px;
    border: 2px solid rgb(180, 200, 220);
    font-weight: bold;
    font-size: 14px;
    color: rgb(30, 30, 30);
}

.info-table tbody tr:nth-child(even) {
    background: rgb(240, 248, 255);
}

.info-table tbody tr:hover {
    background: rgb(230, 245, 255);
}

.calculation-table {
    width: 100%;
    border-collapse: collapse;
    margin: 15px 0;
    background: rgb(255, 255, 255);
    border: 3px solid rgb(255, 140, 0);
}

.calculation-table td {
    padding: 10px 15px;
    border: 2px solid rgb(255, 200, 150);
    font-weight: bold;
    font-size: 14px;
}

.calculation-table tr:first-child td {
    background: linear-gradient(135deg, rgb(255, 235, 210) 0%, rgb(255, 220, 180) 100%);
    color: rgb(180, 90, 0);
    font-weight: bold;
}

.calculation-table td:last-child {
    text-align: right;
    font-weight: bold;
    color: rgb(0, 100, 0);
}

/* Example Box */
.example-box {
    background: linear-gradient(135deg, rgb(245, 255, 245) 0%, rgb(230, 250, 230) 100%);
    border: 3px solid rgb(76, 175, 80);
    border-left: 8px solid rgb(46, 125, 50);
    padding: 20px;
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.example-box h3, .example-box h4 {
    color: rgb(46, 125, 50);
    font-weight: bold;
    margin-bottom: 10px;
}

/* Question Box */
.question-box {
    background: linear-gradient(135deg, rgb(255, 245, 250) 0%, rgb(250, 235, 245) 100%);
    border: 3px solid rgb(233, 30, 99);
    border-left: 8px solid rgb(194, 24, 91);
    padding: 20px;
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.question-box h4 {
    color: rgb(194, 24, 91);
    font-weight: bold;
    margin-bottom: 10px;
}

.question-box p {
    font-weight: bold;
}

.practice-section {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 4px solid rgb(255, 140, 0);
}

.practice-section h3 {
    font-size: 24px;
    font-weight: bold;
    color: rgb(194, 24, 91);
    margin-bottom: 20px;
    background: linear-gradient(135deg, rgb(255, 240, 245) 0%, rgb(255, 230, 240) 100%);
    padding: 15px;
    border-radius: 10px;
    border: 3px solid rgb(233, 30, 99);
}

/* Toggle Button */
.toggle-btn {
    background: linear-gradient(135deg, rgb(76, 175, 80) 0%, rgb(56, 142, 60) 100%);
    color: rgb(255, 255, 255);
    border: 3px solid rgb(46, 125, 50);
    padding: 12px 25px;
    margin: 15px 0;
    border-radius: 8px;
    cursor: pointer;
    font-size: 15px;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.toggle-btn:hover {
    background: linear-gradient(135deg, rgb(56, 142, 60) 0%, rgb(46, 125, 50) 100%);
    transform: scale(1.05);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3);
}

.hidden-content {
    display: none;
    margin-top: 15px;
    padding: 20px;
    background: rgb(255, 255, 255);
    border: 3px solid rgb(200, 200, 200);
    border-radius: 8px;
}

.hidden-content p, .hidden-content li {
    font-weight: bold;
}

/* Flowchart Container */
.flowchart-container {
    background: rgb(255, 255, 255);
    padding: 30px;
    margin: 20px 0;
    border: 3px solid rgb(65, 105, 155);
    border-radius: 15px;
    text-align: center;
    overflow-x: auto;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.flowchart-container svg {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-weight: bold;
}

/* Mind Map Container */
.mindmap-container {
    background: rgb(255, 255, 255);
    padding: 30px;
    margin: 20px 0;
    border: 3px solid rgb(255, 140, 0);
    border-radius: 15px;
    text-align: center;
    overflow-x: auto;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.mindmap-container svg {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-weight: bold;
}

/* Footer */
.footer {
    background: linear-gradient(135deg, rgb(45, 85, 135) 0%, rgb(65, 105, 165) 100%);
    color: rgb(255, 255, 255);
    text-align: center;
    padding: 25px;
    margin-top: 40px;
    border-radius: 15px;
    border: 4px solid rgb(25, 55, 95);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.2);
}

.footer p {
    font-weight: bold;
    margin: 10px 0;
    color: rgb(255, 255, 255);
}

/* Print Styles */
@media print {
    .navigation-box {
        display: none;
    }
    
    .header-content {
        margin-bottom: 20px;
    }
    
    .toggle-btn, .print-btn-header {
        display: none;
    }
    
    .hidden-content {
        display: block !important;
    }
    
    .content-section {
        page-break-inside: avoid;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .header {
        padding: 20px;
    }
    
    .header-content h1 {
        font-size: 24px;
    }
    
    .subtitle {
        font-size: 16px;
    }
    
    .nav-header {
        flex-direction: column;
        gap: 15px;
    }
    
    .nav-header h2 {
        font-size: 22px;
    }
    
    .nav-grid {
        grid-template-columns: 1fr;
    }
    
    .content-section {
        padding: 20px;
    }
    
    .content-section h2 {
        font-size: 24px;
    }
    
    .flowchart-container svg,
    .mindmap-container svg {
        width: 100%;
        height: auto;
    }
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Strong Text */
strong {
    font-weight: bold;
    color: rgb(30, 30, 30);
}

/* Horizontal Rule */
hr {
    border: none;
    border-top: 2px solid rgb(180, 180, 180);
    margin: 20px 0;
}