/* ===== CSS RESET & BASE ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* OKLCH Color System - Unified Dark Industrial Palette */
    /* Unified background - very dark warm gray */
    --bg-primary: oklch(8% 0.008 60);
    --bg-section: oklch(8% 0.008 60);
    --bg-hover: oklch(12% 0.012 60);
    --bg-card: oklch(10% 0.01 60);
    
    /* Line/Divider colors - Soft, subtle */
    --line-internal: oklch(55% 0.1 55 / 0.3);
    --line-major: oklch(55% 0.12 55 / 0.4);
    --line-accent: oklch(65% 0.14 55);
    
    /* Category colors - Desaturated per SKILL.md */
    --cat-game: oklch(65% 0.16 55);      /* Amber */
    --cat-cloud: oklch(65% 0.12 180);    /* Teal */
    --cat-software: oklch(70% 0.1 120);  /* Olive */
    
    /* Accent colors - Amber/Copper */
    --accent-primary: oklch(65% 0.16 55);
    --accent-secondary: oklch(55% 0.14 50);
    --accent-glow: oklch(70% 0.18 55 / 0.25);
    --accent-muted: oklch(45% 0.1 55);
    
    /* Text colors - higher contrast for dark backgrounds */
    --text-primary: oklch(96% 0.015 60);
    --text-secondary: oklch(80% 0.025 60);
    --text-tertiary: oklch(65% 0.02 60);
    --text-muted: oklch(50% 0.015 60);
    
    /* Semantic colors */
    --success: oklch(65% 0.14 145);
    --warning: oklch(72% 0.15 85);
    
    /* Spacing (4pt base) */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 12px;
    --space-lg: 16px;
    --space-xl: 24px;
    --space-2xl: 32px;
    --space-3xl: 48px;
    
    /* Typography */
    --font-display: 'Space Grotesk', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    /* Fluid type scale */
    --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
    --text-sm: clamp(0.8125rem, 0.75rem + 0.3vw, 0.9375rem);
    --text-base: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
    --text-lg: clamp(1rem, 0.9rem + 0.5vw, 1.25rem);
    --text-xl: clamp(1.25rem, 1rem + 1vw, 1.75rem);
    --text-2xl: clamp(1.5rem, 1.2rem + 1.5vw, 2.5rem);
    --text-3xl: clamp(2rem, 1.5rem + 2.5vw, 3.5rem);
    
    /* Animation timing */
    --ease-out-quart: cubic-bezier(0.25, 1, 0.5, 1);
    --ease-out-quint: cubic-bezier(0.22, 1, 0.36, 1);
    --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
    
    /* Transitions */
    --transition-fast: 150ms var(--ease-out-quart);
    --transition-base: 250ms var(--ease-out-quart);
    --transition-slow: 400ms var(--ease-out-quart);
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-mono);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    min-height: 100vh;
    overflow: hidden;
}

/* ===== BACKGROUND GRID ===== */
.bg-grid {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: -1;
    opacity: 0.25;
    background-image: 
        linear-gradient(to right, oklch(20% 0.015 60 / 0.4) 1px, transparent 1px),
        linear-gradient(to bottom, oklch(20% 0.015 60 / 0.4) 1px, transparent 1px);
    background-size: 50px 50px;
}

.bg-grid::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at center, transparent 0%, var(--bg-primary) 70%);
}

/* ===== GRID LAYOUT - EXPLICIT BORDERS ===== */
.grid-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto auto 1fr;
    grid-template-areas:
        "intro links"
        "skills skills"
        "projects projects";
    gap: 0;
    height: 100vh;
    max-width: 1400px;
    margin: 0 auto;
    border: 1px solid var(--line-internal);
    /* Explicit grid lines using background */
    background: 
        linear-gradient(to right, var(--line-major) 1px, transparent 1px) 50% 0 / 1px 100% no-repeat,
        linear-gradient(to bottom, var(--line-major) 1px, transparent 1px) 0 33.33% / 100% 1px no-repeat,
        linear-gradient(to bottom, var(--line-major) 1px, transparent 1px) 0 66.66% / 100% 1px no-repeat;
}

/* Grid area assignments */
.intro { grid-area: intro; }
.links { grid-area: links; }
.skills { grid-area: skills; }
.projects { grid-area: projects; }

/* ===== SECTION STYLES - UNIFIED BACKGROUND ===== */
.section {
    background: var(--bg-section);
    padding: var(--space-xl);
    position: relative;
    overflow: hidden;
    transition: background-color var(--transition-base);
}

/* Remove old section-based borders */
.section:nth-child(2n),
.section:nth-child(2n)::before {
    border: none;
    content: none;
}

/* Major horizontal divider (row 2) with sinus curve animation */
.skills {
    position: relative;
    overflow: hidden;
    padding-top: calc(var(--space-xl) + 8px);
}

/* Animated sinus curve on horizontal dividers */
.skills::before {
    content: '';
    position: absolute;
    top: 5px;
    left: 0;
    width: 400%;
    height: 8px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='8' viewBox='0 0 200 8'%3E%3Cpath d='M0 4 Q 6.25 1, 12.5 4 T 25 4 T 37.5 4 T 50 4 T 62.5 4 T 75 4 T 87.5 4 T 100 4 T 112.5 4 T 125 4 T 137.5 4 T 150 4 T 162.5 4 T 175 4 T 187.5 4 T 200 4' stroke='%23cd853f' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: repeat-x;
    background-size: 200px 8px;
    opacity: 0.7;
    animation: sine-flow 10s linear infinite;
    z-index: 1;
    pointer-events: none;
}

/* Major horizontal divider for projects (row 3) */
.projects {
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    padding: var(--space-xl);
    padding-top: calc(var(--space-xl) + 8px);
    position: relative;
    overflow: hidden;
}

/* Animated sinus curve on projects border */
.projects::before {
    content: '';
    position: absolute;
    top: 5px;
    left: 0;
    width: 400%;
    height: 8px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='8' viewBox='0 0 200 8'%3E%3Cpath d='M0 4 Q 6.25 1, 12.5 4 T 25 4 T 37.5 4 T 50 4 T 62.5 4 T 75 4 T 87.5 4 T 100 4 T 112.5 4 T 125 4 T 137.5 4 T 150 4 T 162.5 4 T 175 4 T 187.5 4 T 200 4' stroke='%23cd853f' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: repeat-x;
    background-size: 200px 8px;
    opacity: 0.7;
    animation: sine-flow 12s linear infinite;
    animation-delay: -4s;
    z-index: 1;
    pointer-events: none;
}

@keyframes sine-flow {
    0% {
        transform: translateX(0);
    }
    100% {
        transform: translateX(-200px);
    }
}

/* Hover effect - subtle background change instead of shadow */
.section:hover {
    background: oklch(9% 0.01 60);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--line-internal);
}

.section-label {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 500;
    color: var(--accent-primary);
    letter-spacing: 0.15em;
    text-transform: uppercase;
}

/* ===== INTRO SECTION ===== */
.intro {
    grid-column: 1;
    grid-row: 1;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.status-dot {
    width: 8px;
    height: 8px;
    background: var(--success);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--success);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(0.9); }
}

.status-text {
    font-size: var(--text-xs);
    color: var(--success);
}

.name {
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 700;
    line-height: 1.1;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
    letter-spacing: -0.02em;
}

.tagline {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    color: var(--accent-primary);
    margin-bottom: var(--space-lg);
    font-weight: 500;
}

.bio {
    font-size: var(--text-base);
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-xl);
    max-width: 45ch;
}

.stats-row {
    display: flex;
    gap: var(--space-2xl);
}

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

.stat-value {
    font-family: var(--font-display);
    font-size: var(--text-2xl);
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1;
}

.stat-label {
    font-size: var(--text-xs);
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-top: var(--space-xs);
}

/* ===== LINKS SECTION ===== */
.links {
    grid-column: 2;
    grid-row: 1;
}

.links-grid {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.link-card {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-card);
    border: 1px solid var(--line-internal);
    border-radius: 4px;
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

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

.link-icon {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-hover);
    border-radius: 4px;
    transition: all var(--transition-base);
    border: 1px solid var(--line-internal);
}

.link-card:hover .link-icon {
    background: var(--accent-muted);
    border-color: var(--accent-muted);
}

.link-icon svg {
    width: 20px;
    height: 20px;
    stroke: var(--text-secondary);
    transition: stroke var(--transition-base);
}

.link-card:hover .link-icon svg {
    stroke: var(--text-primary);
}

.link-content {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.link-name {
    font-family: var(--font-display);
    font-size: var(--text-base);
    font-weight: 500;
}

.link-handle {
    font-size: var(--text-xs);
    color: var(--text-tertiary);
    font-family: var(--font-mono);
}

/* ===== SKILLS SECTION ===== */
.skills {
    grid-column: 1 / -1;
    grid-row: 2;
}

.skills-filter {
    display: flex;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
    flex-wrap: wrap;
}

.filter-btn {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-secondary);
    background: var(--bg-card);
    border: 1px solid var(--line-internal);
    border-radius: 4px;
    padding: var(--space-sm) var(--space-lg);
    cursor: pointer;
    transition: all var(--transition-base);
}

.filter-btn:hover {
    background: var(--bg-hover);
    border-color: var(--line-accent);
    color: var(--text-primary);
}

.filter-btn.active {
    background: var(--accent-muted);
    border-color: var(--accent-primary);
    color: var(--text-primary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    grid-template-rows: repeat(4, 1fr);
    gap: var(--space-md);
    max-height: calc((4 * 52px) + (3 * 12px));
    overflow-y: auto;
    overflow-x: hidden;
    padding-right: var(--space-md);
    margin-right: calc(var(--space-md) * -1);
}

/* Skills Grid Scrollbar - Industrial Style */
.skills-grid {
    /* Firefox scrollbar support */
    scrollbar-width: thin;
    scrollbar-color: var(--accent-primary) var(--bg-card);
}

.skills-grid::-webkit-scrollbar {
    width: 4px;
}

.skills-grid::-webkit-scrollbar-track {
    background: var(--bg-card);
    border-left: 1px solid var(--line-internal);
    border-radius: 0;
}

.skills-grid::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: 0;
    border: none;
}

.skills-grid::-webkit-scrollbar-thumb:hover {
    background: var(--line-accent);
    box-shadow: 0 0 4px var(--accent-glow);
}

.skill-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-card);
    border: 1px solid var(--line-internal);
    border-radius: 4px;
    transition: all var(--transition-base);
    min-height: 52px;
}

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

.skill-item.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.skill-item.fade-out {
    opacity: 0;
    transform: scale(0.95);
}

.skill-name {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.skill-item.primary .skill-name {
    color: var(--accent-primary);
}

/* Category colors on skill names - no badges */
.skill-item.cat-game .skill-name {
    color: var(--cat-game);
}

.skill-item.cat-cloud .skill-name {
    color: var(--cat-cloud);
}

.skill-item.cat-software .skill-name {
    color: var(--cat-software);
}

/* ===== PROJECTS SECTION ===== */
.project-count {
    font-size: var(--text-xs);
    color: var(--text-tertiary);
    background: var(--bg-card);
    padding: var(--space-xs) var(--space-md);
    border-radius: 4px;
    border: 1px solid var(--line-internal);
}

.projects-scroll {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--space-lg);
    padding-right: var(--space-md);
    margin-right: calc(var(--space-md) * -1);
}

/* Projects Scrollbar - Industrial Style */
.projects-scroll {
    /* Firefox scrollbar support */
    scrollbar-width: thin;
    scrollbar-color: var(--accent-primary) var(--bg-card);
}

.projects-scroll::-webkit-scrollbar {
    width: 6px;
}

.projects-scroll::-webkit-scrollbar-track {
    background: var(--bg-card);
    border-left: 1px solid var(--line-internal);
    border-radius: 0;
}

.projects-scroll::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: 0;
    border: none;
}

.projects-scroll::-webkit-scrollbar-thumb:hover {
    background: var(--line-accent);
    box-shadow: 0 0 4px var(--accent-glow);
}

/* Project Cards */
.project-card {
    background: var(--bg-card);
    border: 1px solid var(--line-internal);
    border-radius: 4px;
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-base), border-color var(--transition-base), background-color var(--transition-base);
    transform-style: preserve-3d;
    perspective: 1000px;
}

.project-card:hover {
    border-color: var(--line-accent);
    background: var(--bg-hover);
}

.project-card.tilting {
    transition: none;
}

.project-header {
    margin-bottom: var(--space-md);
}

.project-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-sm);
}

.project-type {
    font-size: var(--text-xs);
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.project-status {
    font-size: var(--text-xs);
    color: var(--accent-primary);
    background: oklch(20% 0.04 55 / 0.4);
    padding: 2px var(--space-sm);
    border-radius: 4px;
    border: 1px solid var(--line-internal);
}

.project-status.published {
    color: var(--success);
    background: oklch(15% 0.04 145 / 0.4);
    border-color: oklch(30% 0.06 145);
}

.project-status.live {
    color: var(--warning);
    background: oklch(20% 0.05 85 / 0.4);
    border-color: oklch(35% 0.08 85);
}

.project-title {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.3;
}

.project-description {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-md);
    flex: 1;
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
    margin-bottom: var(--space-md);
}

.tech-tag {
    font-size: var(--text-xs);
    color: var(--text-secondary);
    background: var(--bg-hover);
    padding: 4px 8px;
    border-radius: 3px;
    border: 1px solid var(--line-internal);
}

.project-links {
    display: flex;
    gap: var(--space-md);
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    font-size: var(--text-xs);
    color: var(--accent-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.project-link:hover {
    color: var(--text-primary);
}

.project-link.disabled {
    color: var(--text-muted);
    cursor: not-allowed;
}

.project-link svg {
    width: 14px;
    height: 14px;
}

/* ===== ANIMATIONS ===== */
[data-animate] {
    opacity: 0;
    transform: translateY(20px);
}

[data-animate="slide-right"] {
    transform: translateX(-30px);
}

[data-animate="slide-left"] {
    transform: translateX(30px);
}

[data-animate="fade-in"] {
    transform: none;
}

.animate-in {
    opacity: 1;
    transform: translate(0);
    transition: opacity 600ms var(--ease-out-quart), transform 600ms var(--ease-out-quart);
}

/* Staggered delays */
[data-animate]:nth-child(1).animate-in { transition-delay: 0ms; }
[data-animate]:nth-child(2).animate-in { transition-delay: 100ms; }
[data-animate]:nth-child(3).animate-in { transition-delay: 200ms; }
[data-animate]:nth-child(4).animate-in { transition-delay: 300ms; }

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
    .grid-container {
        grid-template-columns: 1fr;
        grid-template-rows: auto;
        height: auto;
        min-height: 100vh;
        overflow-y: auto;
    }
    
    .intro,
    .links {
        grid-column: 1;
    }
    
    /* Grid layout changes for mobile - single column */
    .grid-container {
        grid-template-columns: 1fr;
        grid-template-areas:
            "intro"
            "links"
            "skills"
            "projects";
        background: none;
    }
    
    .section {
        border-top: 1px solid var(--line-major);
    }
    
    .projects {
        grid-row: auto;
        max-height: 600px;
    }
    
    .projects-scroll {
        grid-template-columns: 1fr;
    }
    
    body {
        overflow-y: auto;
    }
    
    .skills-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    }
}

@media (max-width: 640px) {
    .grid-container {
        border: none;
    }
    
    .section {
        padding: var(--space-md);
    }
    
    .stats-row {
        gap: var(--space-lg);
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .skills-filter {
        gap: var(--space-sm);
    }
    
    .filter-btn {
        padding: var(--space-xs) var(--space-md);
    }
}

/* ===== REDUCED MOTION ===== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .status-dot {
        animation: none;
    }

    .skills::before,
    .projects::before {
        animation: none;
        opacity: 0.15;
    }
}

/* ===== FOCUS STYLES ===== */
a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}