:root {
    --color-primary: #00ffd1;
    --color-primary-dark: #00ccaa;
    --color-primary-light: #33ffdd;
    --color-secondary: #888888;
    --color-success: #00ff88;
    --color-warning: #ffaa00;
    --color-danger: #ff4444;
    --color-text: #e0e0e0;
    --color-text-light: #999999;
    --color-text-dark: #666666;
    --color-bg: #0a0a0a;
    --color-bg-alt: #111111;
    --color-bg-hover: #1a1a1a;
    --color-bg-card: #151515;
    --color-border: #222222;
    --color-border-light: #333333;
    --color-shadow: rgba(0, 0, 0, 0.5);
    
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', 'Courier New', monospace;
    
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s ease;
}

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

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background-color: var(--color-bg);
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(0, 255, 209, 0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(0, 255, 209, 0.02) 0%, transparent 50%),
        linear-gradient(180deg, transparent 0%, rgba(0, 255, 209, 0.01) 100%);
    background-attachment: fixed;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        repeating-linear-gradient(0deg, transparent, transparent 2px, rgba(0, 255, 209, 0.02) 2px, rgba(0, 255, 209, 0.02) 4px),
        repeating-linear-gradient(90deg, transparent, transparent 2px, rgba(0, 255, 209, 0.02) 2px, rgba(0, 255, 209, 0.02) 4px);
    pointer-events: none;
    z-index: 0;
    opacity: 0.3;
}

body > * {
    position: relative;
    z-index: 1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Header */
.header {
    background: transparent;
    color: var(--color-text);
    padding: var(--spacing-2xl) 0;
    border-bottom: 1px solid var(--color-border);
    position: relative;
}

.header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
    opacity: 0.5;
}

.header-content {
    text-align: center;
}

.logo {
    font-size: 2.5rem;
    font-weight: 300;
    margin-bottom: var(--spacing-sm);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text);
    font-family: var(--font-mono);
}

.tagline {
    font-size: 0.875rem;
    color: var(--color-text-light);
    font-weight: 300;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    font-family: var(--font-mono);
}

/* Main Content */
.main {
    padding: var(--spacing-2xl) 0;
}

.intro {
    margin-bottom: var(--spacing-2xl);
    padding: var(--spacing-xl);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    border-left: 2px solid var(--color-primary);
    position: relative;
    transition: var(--transition);
}


.intro h2 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
    font-weight: 400;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    font-family: var(--font-mono);
}

.intro p {
    font-size: 0.95rem;
    color: var(--color-text-light);
    line-height: 1.8;
    font-weight: 300;
}

.intro h2:not(:first-child) {
    margin-top: var(--spacing-xl);
}

.intro code {
    font-family: var(--font-mono);
    font-size: 0.85em;
    background: rgba(0, 255, 209, 0.1);
    padding: 0.2em 0.4em;
    border-radius: var(--radius-sm);
    color: var(--color-primary-light);
    border: 1px solid rgba(0, 255, 209, 0.2);
}

.intro ul {
    margin: var(--spacing-md) 0;
    padding-left: var(--spacing-xl);
    list-style: none;
}

.intro li {
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.8;
    font-weight: 300;
    margin-bottom: var(--spacing-sm);
    position: relative;
    padding-left: var(--spacing-md);
}

.intro li::before {
    content: '›';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-family: var(--font-mono);
}

.intro li strong {
    color: var(--color-text);
    font-weight: 500;
}

/* Stacks Section */
.stacks {
    margin-bottom: var(--spacing-2xl);
}

.stacks h2 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xl);
    color: var(--color-text);
    font-weight: 300;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    font-family: var(--font-mono);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
    position: relative;
}

.stacks h2::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100px;
    height: 1px;
    background: var(--color-primary);
}

.stacks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stack-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: var(--spacing-xl);
    transition: var(--transition);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.stack-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 2px;
    height: 100%;
    background: var(--color-primary);
    transform: scaleY(0);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    opacity: 0.8;
}

.stack-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, transparent, rgba(0, 255, 209, 0.05));
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.stack-card:hover {
    transform: translateY(-2px);
    border-color: var(--color-primary);
}

.stack-card:hover::before {
    transform: scaleY(1);
}

.stack-card:hover::after {
    opacity: 1;
}

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

.stack-icon {
    width: 2.5rem;
    height: 2.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.stack-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.stack-title {
    font-size: 1rem;
    font-weight: 400;
    color: var(--color-text);
    flex: 1;
    letter-spacing: 0.05em;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.stack-summary {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    font-size: 0.875rem;
    font-weight: 300;
    line-height: 1.6;
}

.stack-focus {
    font-size: 0.75rem;
    color: var(--color-primary);
    font-weight: 400;
    margin-bottom: var(--spacing-md);
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    padding: var(--spacing-xs) var(--spacing-sm);
    border: 1px solid var(--color-primary);
    display: inline-block;
    border-radius: var(--radius-sm);
    background: rgba(0, 255, 209, 0.05);
}

.stack-stats {
    display: flex;
    gap: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
    font-size: 0.75rem;
    color: var(--color-text-dark);
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.stack-stat {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.guides-list {
    margin-top: var(--spacing-md);
}

.guides-list h4 {
    font-size: 0.7rem;
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-dark);
    margin-bottom: var(--spacing-sm);
    font-family: var(--font-mono);
}

.guides-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--spacing-xs);
}

.guide-item {
    padding: var(--spacing-sm) var(--spacing-md);
    background: transparent;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    color: var(--color-text-light);
    text-decoration: none;
    transition: var(--transition-fast);
    border: 1px solid var(--color-border);
    font-family: var(--font-mono);
    display: block;
    position: relative;
}

.guide-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--color-primary);
    transform: scaleY(0);
    transition: transform 0.2s ease;
}

.guide-item:hover {
    background: rgba(0, 255, 209, 0.05);
    border-color: var(--color-primary);
    color: var(--color-text);
    transform: translateX(4px);
}

.guide-item:hover::before {
    transform: scaleY(1);
}

.guide-item.always-apply {
    border-left: 2px solid var(--color-success);
    padding-left: calc(var(--spacing-md) - 2px);
}

.guide-item.always-apply::before {
    background: var(--color-success);
}

/* Common Principles */
.common-principles {
    margin-top: var(--spacing-2xl);
    padding-top: var(--spacing-2xl);
    border-top: 1px solid var(--color-border);
    position: relative;
}

.common-principles::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
    opacity: 0.5;
}

.common-principles h2 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xl);
    color: var(--color-text);
    font-weight: 300;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    font-family: var(--font-mono);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
    position: relative;
}

.common-principles h2::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100px;
    height: 1px;
    background: var(--color-primary);
}

.principles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.principle-card {
    background: var(--color-bg-card);
    border-radius: var(--radius-sm);
    padding: var(--spacing-xl);
    border: 1px solid var(--color-border);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.principle-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 2px;
    height: 100%;
    background: var(--color-primary);
    transform: scaleY(0);
    transition: transform 0.3s ease;
    opacity: 0.8;
}

.principle-card:hover {
    transform: translateY(-2px);
    border-color: var(--color-primary);
}

.principle-card:hover::before {
    transform: scaleY(1);
}


.principle-card h3 {
    font-size: 1rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
    font-weight: 400;
    letter-spacing: 0.05em;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.principle-card p {
    color: var(--color-text-light);
    line-height: 1.7;
    font-size: 0.875rem;
    font-weight: 300;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    overflow-y: auto;
    padding: var(--spacing-xl);
}

.modal.active {
    display: flex;
    align-items: flex-start;
    justify-content: center;
}

.modal-content {
    background-color: var(--color-bg-card);
    margin: var(--spacing-xl) auto;
    border-radius: var(--radius-sm);
    width: 100%;
    max-width: 900px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.8);
    border: 1px solid var(--color-border);
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    position: relative;
}

.modal-content::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 2px;
    height: 100%;
    background: var(--color-primary);
    opacity: 0.8;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-xl);
    border-bottom: 1px solid var(--color-border);
    position: relative;
    gap: var(--spacing-md);
}

.modal-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-shrink: 0;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    color: var(--color-text-light);
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    transition: var(--transition-fast);
    white-space: nowrap;
}

.action-btn:hover {
    background: rgba(0, 255, 209, 0.1);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.action-btn:active {
    transform: scale(0.98);
}

.action-btn.success {
    background: rgba(0, 255, 136, 0.15);
    border-color: var(--color-success);
    color: var(--color-success);
}

.action-icon {
    font-size: 0.9rem;
}

.action-btn-large {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 0.8rem;
    flex: 1;
    justify-content: center;
}

.modal-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, var(--color-primary), transparent);
    opacity: 0.5;
}

.modal-header h2 {
    font-size: 1.25rem;
    color: var(--color-text);
    margin: 0;
    font-weight: 400;
    letter-spacing: 0.05em;
    font-family: var(--font-mono);
    text-transform: uppercase;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.modal-icon {
    width: 1.5rem;
    height: 1.5rem;
    object-fit: contain;
}

.modal-close {
    background: transparent;
    border: 1px solid var(--color-border);
    font-size: 1.5rem;
    color: var(--color-text-light);
    cursor: pointer;
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
    font-family: var(--font-mono);
    line-height: 1;
}

.modal-close:hover {
    background: rgba(0, 255, 209, 0.1);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.modal-body {
    padding: var(--spacing-xl);
    overflow-y: auto;
    flex: 1;
}

.modal-footer {
    display: none;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    border-top: 1px solid var(--color-border);
    background: var(--color-bg-alt);
}

.modal-footer.visible {
    display: flex;
}

.modal-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, var(--color-primary), transparent);
    opacity: 0.3;
}

.modal-content pre {
    background: var(--color-bg);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    line-height: 1.6;
    border: 1px solid var(--color-border);
    border-left: 2px solid var(--color-primary);
}

.modal-content code {
    font-family: var(--font-mono);
    font-size: 0.85em;
    background: rgba(0, 255, 209, 0.1);
    padding: 0.2em 0.4em;
    border-radius: var(--radius-sm);
    color: var(--color-primary-light);
    border: 1px solid rgba(0, 255, 209, 0.2);
}

.modal-content pre code {
    background: transparent;
    padding: 0;
    border: none;
    color: var(--color-text-light);
}

.modal-content h1,
.modal-content h2,
.modal-content h3,
.modal-content h4 {
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
    font-weight: 400;
    letter-spacing: 0.05em;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.modal-content h1 {
    font-size: 1.5rem;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: var(--spacing-sm);
}

.modal-content h2 {
    font-size: 1.25rem;
}

.modal-content h3 {
    font-size: 1rem;
}

.modal-content h1:first-child,
.modal-content h2:first-child,
.modal-content h3:first-child {
    margin-top: 0;
}

.modal-content p {
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
    color: var(--color-text-light);
    font-weight: 300;
}

.modal-content ul,
.modal-content ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-xl);
}

.modal-content li {
    margin-bottom: var(--spacing-xs);
    line-height: 1.7;
    color: var(--color-text-light);
}

.modal-content blockquote {
    border-left: 2px solid var(--color-primary);
    padding-left: var(--spacing-md);
    margin: var(--spacing-md) 0;
    color: var(--color-text-light);
    font-style: italic;
    background: rgba(0, 255, 209, 0.05);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
}

.modal-content table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--spacing-md) 0;
    border: 1px solid var(--color-border);
}

.modal-content table th,
.modal-content table td {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--color-border);
    text-align: left;
}

.modal-content table th {
    background: var(--color-bg-alt);
    font-weight: 400;
    color: var(--color-text);
    font-family: var(--font-mono);
    text-transform: uppercase;
    font-size: 0.8rem;
    letter-spacing: 0.05em;
}

/* Footer */
.footer {
    background: transparent;
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-2xl);
    border-top: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-text-dark);
    font-size: 0.75rem;
    font-family: var(--font-mono);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
    opacity: 0.5;
}

/* Responsive */
@media (max-width: 768px) {
    .logo {
        font-size: 2rem;
    }
    
    .tagline {
        font-size: 1rem;
    }
    
    .stacks-grid {
        grid-template-columns: 1fr;
    }
    
    .principles-grid {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        margin: var(--spacing-md);
        max-height: 95vh;
    }
    
    .modal-header,
    .modal-body {
        padding: var(--spacing-md);
    }
    
    .modal-header {
        flex-wrap: wrap;
    }
    
    .modal-header h2 {
        flex: 1 1 100%;
        margin-bottom: var(--spacing-sm);
    }
    
    .modal-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .action-btn .action-text {
        display: none;
    }
    
    .action-btn-large .action-text,
    .action-btn-large span:not(.action-icon) {
        display: inline;
    }
    
    .modal-footer {
        flex-direction: column;
    }
    
    .modal-footer .action-btn-large {
        width: 100%;
    }
}

/* Loading State */
.loading {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--color-text-light);
    font-family: var(--font-mono);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    font-size: 0.875rem;
}

.loading::after {
    content: '...';
    animation: dots 1.5s steps(4, end) infinite;
    color: var(--color-primary);
}

@keyframes dots {
    0%, 20% { content: '.'; }
    40% { content: '..'; }
    60%, 100% { content: '...'; }
}

/* Scrollbar styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-primary);
}

/* Selection */
::selection {
    background: rgba(0, 255, 209, 0.3);
    color: var(--color-text);
}

::-moz-selection {
    background: rgba(0, 255, 209, 0.3);
    color: var(--color-text);
}

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

a:hover {
    color: var(--color-primary-light);
}

.modal-content a {
    color: var(--color-primary);
    border-bottom: 1px solid rgba(0, 255, 209, 0.3);
    transition: var(--transition-fast);
}

.modal-content a:hover {
    border-bottom-color: var(--color-primary);
    color: var(--color-primary-light);
}

/* Buttons */
button {
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    font-size: 0.8rem;
}

/* Code blocks in modal */
.modal-content pre {
    position: relative;
}

.modal-content pre::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 2px;
    height: 100%;
    background: var(--color-primary);
    opacity: 0.6;
}

/* Smooth transitions for all interactive elements */
.stack-card,
.principle-card,
.guide-item,
.modal-close {
    will-change: transform;
}

/* Focus states for accessibility */
*:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Image styling */
.modal-content img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    margin: var(--spacing-md) 0;
}