/* 
 * SAP ABAP Mastery: From Beginner to Expert
 * Main Stylesheet
 */

/* ===== Base Styles ===== */
:root {
    /* Color Palette */
    --primary: #0066CC;       /* SAP Blue */
    --secondary: #FF5500;     /* Orange for highlights */
    --background: #F5F6F7;    /* Light gray for main background */
    --text: #333333;          /* Dark gray for main text */
    --light-text: #6c757d;    /* Lighter text for secondary content */
    --white: #FFFFFF;
    --light-gray: #e9ecef;
    --border-color: #dee2e6;
    
    /* Skill Level Colors */
    --beginner: #4CAF50;      /* Green */
    --intermediate: #FFC107;  /* Amber */
    --advanced: #FF5722;      /* Deep Orange */
    --expert: #9C27B0;        /* Purple */
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2.5rem;
    
    /* Border Radius */
    --border-radius-sm: 0.25rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 1rem;
    
    /* Transitions */
    --transition-speed: 0.3s;
}

/* Dark Mode Variables */
.dark-mode {
    --primary: #4D94FF;       /* Lighter SAP Blue for dark mode */
    --background: #121212;    /* Dark background */
    --text: #E1E1E1;          /* Light text for dark mode */
    --light-text: #AAAAAA;    /* Lighter text for secondary content */
    --light-gray: #2A2A2A;    /* Darker gray for dark mode */
    --border-color: #444444;  /* Darker border for dark mode */
}

body {
    font-family: 'Open Sans', sans-serif;
    color: var(--text);
    background-color: var(--background);
    line-height: 1.6;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Roboto', sans-serif;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

code, pre {
    font-family: 'Source Code Pro', monospace;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--secondary);
}

.btn-primary {
    background-color: var(--primary);
    border-color: var(--primary);
}

.btn-primary:hover {
    background-color: #0055AA;
    border-color: #0055AA;
}

.btn-outline-primary {
    color: var(--primary);
    border-color: var(--primary);
}

.btn-outline-primary:hover {
    background-color: var(--primary);
    border-color: var(--primary);
}

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

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

/* ===== Layout & Containers ===== */
.container {
    max-width: 1200px;
    padding: 0 var(--spacing-md);
}

.section-header {
    margin-bottom: var(--spacing-xl);
}

.content-card {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    transition: background-color var(--transition-speed), box-shadow var(--transition-speed);
}

.dark-mode .content-card {
    background-color: #1E1E1E;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.card {
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
    border: 1px solid var(--border-color);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

/* ===== Header & Navigation ===== */
.header {
    margin-bottom: 56px; /* Height of the fixed navbar */
}

.navbar {
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    transition: background-color var(--transition-speed);
}

.dark-mode .navbar {
    background-color: #1E1E1E !important;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.dark-mode .navbar-light .navbar-brand,
.dark-mode .navbar-light .navbar-nav .nav-link {
    color: var(--text);
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.5rem;
}

.nav-link {
    font-weight: 600;
    padding: 0.5rem 1rem;
}

.dropdown-menu {
    border-radius: var(--border-radius-sm);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--border-color);
    transition: background-color var(--transition-speed);
}

.dark-mode .dropdown-menu {
    background-color: #1E1E1E;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.dark-mode .dropdown-item {
    color: var(--text);
}

.dark-mode .dropdown-item:hover {
    background-color: #2A2A2A;
}

/* ===== Hero Section ===== */
.hero-section {
    padding: calc(var(--spacing-xl) * 2) 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    transition: background var(--transition-speed);
}

.dark-mode .hero-section {
    background: linear-gradient(135deg, #2A2A2A 0%, #1A1A1A 100%);
}

.hero-section h1 {
    font-size: 3.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--primary);
}

.hero-section h2 {
    font-weight: 400;
    margin-bottom: var(--spacing-lg);
}

.hero-image {
    text-align: center;
}

.hero-image img {
    max-width: 100%;
    height: auto;
}

.quick-link-card {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-lg);
    text-align: center;
    height: 100%;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform var(--transition-speed), background-color var(--transition-speed);
}

.dark-mode .quick-link-card {
    background-color: #1E1E1E;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.quick-link-card:hover {
    transform: translateY(-5px);
}

/* ===== Learning Path Section ===== */
.learning-path-section {
    background-color: var(--white);
    transition: background-color var(--transition-speed);
}

.dark-mode .learning-path-section {
    background-color: #1A1A1A;
}

.learning-path-timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

.timeline-container {
    position: relative;
}

.timeline-container::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    left: 20px;
    width: 4px;
    background-color: var(--primary);
    border-radius: 2px;
}

.timeline-item {
    position: relative;
    padding-left: 60px;
    margin-bottom: var(--spacing-xl);
}

.timeline-dot {
    position: absolute;
    left: 12px;
    top: 15px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--white);
    border: 4px solid var(--primary);
    z-index: 1;
}

.timeline-content {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: var(--spacing-lg);
    transition: background-color var(--transition-speed);
}

.dark-mode .timeline-content {
    background-color: #1E1E1E;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.timeline-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.timeline-header h3 {
    margin-right: var(--spacing-md);
    margin-bottom: 0;
}

.timeline-duration {
    margin-left: auto;
    font-weight: 600;
    color: var(--light-text);
}

.timeline-skills {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.skill-tag {
    background-color: var(--light-gray);
    color: var(--text);
    padding: 0.25rem 0.5rem;
    border-radius: var(--border-radius-sm);
    font-size: 0.85rem;
    transition: background-color var(--transition-speed);
}

.dark-mode .skill-tag {
    background-color: #2A2A2A;
}

.timeline-more {
    text-align: center;
    margin-top: var(--spacing-xl);
}

/* Timeline Level Colors */
.timeline-item[data-level="beginner"] .timeline-dot {
    border-color: var(--beginner);
}

.timeline-item[data-level="intermediate"] .timeline-dot {
    border-color: var(--intermediate);
}

.timeline-item[data-level="advanced"] .timeline-dot {
    border-color: var(--advanced);
}

.timeline-item[data-level="expert"] .timeline-dot {
    border-color: var(--expert);
}

/* ===== Content Sections ===== */
.content-section {
    padding: var(--spacing-xl) 0;
    transition: background-color var(--transition-speed);
}

.dark-mode .content-section.bg-light {
    background-color: #1A1A1A !important;
}

.nav-pills .nav-link {
    color: var(--text);
    border-radius: var(--border-radius-sm);
    margin-bottom: var(--spacing-sm);
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.dark-mode .nav-pills .nav-link {
    color: var(--text);
}

.nav-pills .nav-link.active {
    background-color: var(--primary);
    color: var(--white);
}

.nav-pills .nav-link:not(.active):hover {
    background-color: var(--light-gray);
}

.dark-mode .nav-pills .nav-link:not(.active):hover {
    background-color: #2A2A2A;
}

/* Code Blocks */
.code-block {
    margin: var(--spacing-md) 0;
    border-radius: var(--border-radius-sm);
    overflow: hidden;
}

.code-block pre {
    margin: 0;
    padding: 0;
}

.code-block code {
    padding: var(--spacing-md);
    font-size: 0.9rem;
    line-height: 1.5;
}

/* Tables */
.table {
    margin-bottom: var(--spacing-lg);
    border-color: var(--border-color);
}

.dark-mode .table {
    color: var(--text);
}

.dark-mode .table-bordered {
    border-color: var(--border-color);
}

.dark-mode .table-light {
    background-color: #2A2A2A;
    color: var(--text);
}

/* Accordions */
.accordion-item {
    border-color: var(--border-color);
    transition: background-color var(--transition-speed);
}

.dark-mode .accordion-item {
    background-color: #1E1E1E;
}

.accordion-button {
    background-color: var(--white);
    color: var(--text);
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.dark-mode .accordion-button {
    background-color: #1E1E1E;
    color: var(--text);
}

.dark-mode .accordion-button:not(.collapsed) {
    background-color: #2A2A2A;
    color: var(--text);
}

.dark-mode .accordion-button::after {
    filter: invert(1);
}

/* Knowledge Check */
.knowledge-check {
    background-color: var(--light-gray);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-lg);
    transition: background-color var(--transition-speed);
}

.dark-mode .knowledge-check {
    background-color: #2A2A2A;
}

.knowledge-check .card {
    background-color: var(--white);
    transition: background-color var(--transition-speed);
}

.dark-mode .knowledge-check .card {
    background-color: #1E1E1E;
}

.answer-feedback {
    padding: var(--spacing-md);
    border-radius: var(--border-radius-sm);
    margin-top: var(--spacing-md);
}

.answer-feedback.correct {
    background-color: rgba(76, 175, 80, 0.1);
    border: 1px solid var(--beginner);
}

.answer-feedback.incorrect {
    background-color: rgba(244, 67, 54, 0.1);
    border: 1px solid #F44336;
}

/* ===== Projects Section ===== */
.projects-section {
    background-color: var(--white);
    transition: background-color var(--transition-speed);
}

.dark-mode .projects-section {
    background-color: #1A1A1A;
}

.project-filters {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.project-filters .btn-group {
    flex-wrap: wrap;
    justify-content: center;
}

.project-filters .btn {
    margin: 0.25rem;
}

.project-gallery {
    transition: opacity var(--transition-speed);
}

.skills-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

/* ===== Interview Section ===== */
.interview-section {
    transition: background-color var(--transition-speed);
}

.dark-mode .interview-section.bg-light {
    background-color: #1A1A1A !important;
}

.interview-filters {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.interview-filters .btn-group {
    flex-wrap: wrap;
    justify-content: center;
}

.interview-filters .btn {
    margin: 0.25rem;
}

.question-card {
    margin-bottom: var(--spacing-md);
    transition: opacity var(--transition-speed);
}

/* ===== Best Practices Section ===== */
.best-practices-section {
    background-color: var(--white);
    transition: background-color var(--transition-speed);
}

.dark-mode .best-practices-section {
    background-color: #1A1A1A;
}

.category-card {
    height: 100%;
}

.category-icon {
    text-align: center;
}

.tip-card {
    margin-bottom: var(--spacing-lg);
}

/* ===== Resources Section ===== */
.resources-section {
    transition: background-color var(--transition-speed);
}

.dark-mode .resources-section.bg-light {
    background-color: #1A1A1A !important;
}

.resource-card {
    height: 100%;
}

.resource-icon {
    text-align: center;
}

.glossary dt {
    font-weight: 700;
    margin-top: var(--spacing-md);
}

.glossary dd {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-md);
    border-left: 3px solid var(--primary);
}

/* ===== Footer ===== */
.footer {
    background-color: #212529;
    color: var(--white);
    transition: background-color var(--transition-speed);
}

.dark-mode .footer {
    background-color: #121212;
}

.footer h5 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.footer a {
    color: #adb5bd;
    transition: color var(--transition-speed);
}

.footer a:hover {
    color: var(--white);
    text-decoration: none;
}

.social-links a {
    color: #adb5bd;
    transition: color var(--transition-speed);
}

.social-links a:hover {
    color: var(--white);
}

/* ===== Back to Top Button ===== */
#back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: none;
    z-index: 99;
    width: 40px;
    height: 40px;
    text-align: center;
    line-height: 40px;
    border-radius: 50%;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
}

/* ===== Responsive Styles ===== */
@media (max-width: 991.98px) {
    .hero-section {
        text-align: center;
        padding: var(--spacing-xl) 0;
    }
    
    .hero-section h1 {
        font-size: 2.5rem;
    }
    
    .hero-image {
        margin-top: var(--spacing-lg);
    }
    
    .timeline-container::before {
        left: 15px;
    }
    
    .timeline-dot {
        left: 7px;
    }
    
    .timeline-item {
        padding-left: 45px;
    }
}

@media (max-width: 767.98px) {
    .section-header h2 {
        font-size: 2rem;
    }
    
    .project-filters .btn-group,
    .interview-filters .btn-group {
        flex-direction: column;
        width: 100%;
    }
    
    .project-filters .btn,
    .interview-filters .btn {
        margin: 0.25rem 0;
        border-radius: var(--border-radius-sm) !important;
    }
}

@media (max-width: 575.98px) {
    .hero-section h1 {
        font-size: 2rem;
    }
    
    .hero-section h2 {
        font-size: 1.25rem;
    }
    
    .timeline-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .timeline-duration {
        margin-left: 0;
        margin-top: var(--spacing-xs);
    }
}

/* ===== Animations ===== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.fade-in {
    animation: fadeIn 0.5s ease-in-out;
}

@keyframes slideInUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.slide-in-up {
    animation: slideInUp 0.5s ease-in-out;
}

/* ===== Print Styles ===== */
@media print {
    .navbar,
    .footer,
    #back-to-top,
    .btn {
        display: none !important;
    }
    
    body {
        background-color: white !important;
        color: black !important;
    }
    
    .container {
        max-width: 100% !important;
        width: 100% !important;
    }
    
    .content-card,
    .card {
        box-shadow: none !important;
        border: 1px solid #ddd !important;
    }
    
    .collapse {
        display: block !important;
        height: auto !important;
    }
    
    a {
        text-decoration: underline;
        color: #0066CC !important;
    }
    
    a[href]:after {
        content: " (" attr(href) ")";
        font-size: 0.8em;
    }
}