/* ===================================
   Cloud & DevOps Roadmap - Minimal UI
   Inspired by he2.ai & manus.im
   =================================== */

/* CSS Variables - Minimal Design System */
:root {
    /* Colors - Minimal Palette */
    --bg-primary: #ffffff;
    --bg-secondary: #fafafa;
    --bg-tertiary: #f5f5f5;
    --text-primary: #0a0a0a;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --border-color: #e5e5e5;
    --accent-color: #0066ff;
    --accent-hover: #0052cc;
    --success-color: #00c853;
    --warning-color: #ff9800;
    --error-color: #f44336;
    
    /* Spacing - 8px base */
    --space-1: 0.5rem;
    --space-2: 1rem;
    --space-3: 1.5rem;
    --space-4: 2rem;
    --space-6: 3rem;
    --space-8: 4rem;
    
    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, monospace;
    
    /* Transitions */
    --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 var(--space-3);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--text-primary);
}

h1 { font-size: 2.5rem; margin-bottom: var(--space-2); }
h2 { font-size: 2rem; margin-bottom: var(--space-3); }
h3 { font-size: 1.5rem; margin-bottom: var(--space-2); }
h4 { font-size: 1.25rem; margin-bottom: var(--space-2); }

p {
    color: var(--text-secondary);
    margin-bottom: var(--space-2);
    line-height: 1.7;
}

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

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

code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background: var(--bg-tertiary);
    padding: 0.2em 0.4em;
    border-radius: 3px;
    color: var(--text-primary);
}

/* Header */
.header {
    padding: var(--space-6) 0 var(--space-4);
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-primary);
}

.logo {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: var(--space-1);
    color: var(--text-primary);
}

.tagline {
    font-size: 0.95rem;
    color: var(--text-tertiary);
    margin: 0;
}

/* Main Content */
.main {
    padding: var(--space-6) 0;
}

/* Introduction */
.intro {
    margin-bottom: var(--space-8);
}

.intro h2 {
    font-size: 2rem;
    margin-bottom: var(--space-2);
}

.intro > p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-4);
    max-width: 700px;
}

.stats {
    display: flex;
    gap: var(--space-4);
    padding: var(--space-3) 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat strong {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.stat span {
    font-size: 0.875rem;
    color: var(--text-tertiary);
}

/* Stage Section */
.stage {
    margin-bottom: var(--space-8);
}

.stage-header {
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--border-color);
}

.stage-badge {
    display: inline-block;
    padding: 0.375rem 0.875rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: var(--space-2);
}

.stage-badge.beginner {
    background: #e8f5e9;
    color: #2e7d32;
}

.stage-badge.intermediate {
    background: #fff3e0;
    color: #e65100;
}

.stage-badge.advanced {
    background: #fce4ec;
    color: #c2185b;
}

.stage-header h2 {
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
}

.stage-header p {
    font-size: 1rem;
    color: var(--text-tertiary);
    margin: 0;
}

/* Topic Card */
.topic-card {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: var(--space-3);
    background: var(--bg-primary);
    transition: all var(--transition);
}

.topic-card:hover {
    border-color: var(--text-tertiary);
}

.topic-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-3);
    cursor: pointer;
    user-select: none;
}

.topic-title {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.topic-title i {
    width: 24px;
    height: 24px;
    color: var(--text-secondary);
}

.topic-title h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin: 0;
}

.expand-icon {
    width: 20px;
    height: 20px;
    color: var(--text-tertiary);
    transition: transform var(--transition);
}

.topic-card.expanded .expand-icon {
    transform: rotate(180deg);
}

/* Topic Content */
.topic-content {
    display: none;
    padding: 0 var(--space-3) var(--space-3);
    border-top: 1px solid var(--border-color);
}

.topic-card.expanded .topic-content {
    display: block;
}

.topic-overview {
    padding: var(--space-3) 0;
}

.topic-overview p {
    font-size: 1rem;
    margin-bottom: var(--space-2);
}

.duration {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    font-size: 0.875rem;
    color: var(--text-tertiary);
}

.duration i {
    width: 16px;
    height: 16px;
}

/* Study Section */
.study-section {
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-4);
    border-bottom: 1px solid var(--border-color);
}

.study-section:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.study-section h4 {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--space-2);
    color: var(--text-primary);
}

.study-section h4 i {
    width: 18px;
    height: 18px;
}

.content-text {
    font-size: 0.95rem;
    line-height: 1.7;
}

.content-text p {
    margin-bottom: var(--space-2);
}

.content-text strong {
    color: var(--text-primary);
    font-weight: 600;
}

.content-text ul {
    list-style: none;
    margin: var(--space-2) 0;
}

.content-text li {
    padding-left: var(--space-3);
    margin-bottom: var(--space-1);
    position: relative;
}

.content-text li::before {
    content: '•';
    position: absolute;
    left: var(--space-1);
    color: var(--accent-color);
    font-weight: bold;
}

/* Video Grid */
.video-grid {
    display: grid;
    gap: var(--space-2);
}

.video-card {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    transition: all var(--transition);
    text-decoration: none;
}

.video-card:hover {
    border-color: var(--accent-color);
    background: var(--bg-secondary);
    transform: translateX(4px);
}

.video-icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-icon i {
    width: 20px;
    height: 20px;
    color: var(--accent-color);
}

.video-info {
    flex: 1;
}

.video-info strong {
    display: block;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.video-info span {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

/* Resource List */
.resource-list {
    display: grid;
    gap: var(--space-2);
}

.resource-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    transition: all var(--transition);
    text-decoration: none;
}

.resource-item:hover {
    border-color: var(--accent-color);
    background: var(--bg-secondary);
}

.resource-item i {
    width: 18px;
    height: 18px;
    color: var(--text-tertiary);
    flex-shrink: 0;
}

.resource-item strong {
    display: block;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.resource-item span {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

/* Exercise List */
.exercise-list {
    display: grid;
    gap: var(--space-2);
}

.exercise-item {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    padding: var(--space-2);
    background: var(--bg-secondary);
    border-radius: 6px;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.exercise-item i {
    width: 18px;
    height: 18px;
    color: var(--success-color);
    flex-shrink: 0;
    margin-top: 2px;
}

/* Certifications */
.certifications {
    margin-bottom: var(--space-8);
}

.certifications h2 {
    margin-bottom: var(--space-2);
}

.certifications > p {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-4);
}

.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-3);
}

.cert-card {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--space-3);
    background: var(--bg-secondary);
}

.cert-header {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-3);
    padding-bottom: var(--space-2);
    border-bottom: 1px solid var(--border-color);
}

.cert-header i {
    width: 24px;
    height: 24px;
    color: var(--accent-color);
}

.cert-header h3 {
    font-size: 1.125rem;
    margin: 0;
}

.cert-path {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.cert-item {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.cert-item strong {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
}

.cert-item span {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

/* Career Section */
.career {
    margin-bottom: var(--space-8);
}

.career h2 {
    margin-bottom: var(--space-2);
}

.career > p {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-4);
}

.career-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-3);
}

.career-card {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--space-3);
    background: var(--bg-secondary);
}

.career-card i {
    width: 28px;
    height: 28px;
    color: var(--accent-color);
    margin-bottom: var(--space-2);
}

.career-card h3 {
    font-size: 1.125rem;
    margin-bottom: var(--space-2);
}

.career-card ul {
    list-style: none;
}

.career-card li {
    padding: var(--space-1) 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-color);
}

.career-card li:last-child {
    border-bottom: none;
}

/* Footer */
.footer {
    padding: var(--space-4) 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer p {
    font-size: 0.875rem;
    color: var(--text-tertiary);
    margin-bottom: 0.5rem;
}

.footer-note {
    font-size: 0.8rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    html {
        font-size: 15px;
    }
    
    .container {
        padding: 0 var(--space-2);
    }
    
    .header {
        padding: var(--space-4) 0 var(--space-3);
    }
    
    .logo {
        font-size: 1.5rem;
    }
    
    .intro h2 {
        font-size: 1.75rem;
    }
    
    .stats {
        flex-direction: column;
        gap: var(--space-2);
    }
    
    .cert-grid,
    .career-grid {
        grid-template-columns: 1fr;
    }
    
    .topic-header {
        padding: var(--space-2);
    }
    
    .topic-content {
        padding: 0 var(--space-2) var(--space-2);
    }
}

/* Print Styles */
@media print {
    @page {
        margin: 0.5in;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .header {
        border-bottom: 2px solid black;
    }
    
    .topic-content {
        display: block !important;
    }
    
    .expand-icon {
        display: none;
    }
    
    a {
        color: black;
        text-decoration: underline;
    }
}

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

.topic-card {
    animation: fadeIn 0.3s ease;
}

/* Focus Styles for Accessibility */
*:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

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