/* Raycast Design System: CSS Tokens & Portfolio Stylesheet */
:root {
    --canvas: #07080a;
    --surface: #0d0d0d;
    --surface-card: #121212;
    --surface-elevated: #18191a;
    --surface-hover: #1f2022;
    --hairline: #242728;
    --hairline-soft: rgba(255, 255, 255, 0.08);
    --hairline-strong: rgba(255, 255, 255, 0.16);
    
    --text-primary: #ffffff;
    --text-secondary: #9c9c9d;
    --text-muted: #6a6b6c;
    
    --accent-red: #ff6161;
    --accent-red-soft: rgba(255, 97, 97, 0.12);
    --accent-green: #34d399;
    --accent-green-soft: rgba(52, 211, 153, 0.12);
    
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-pill: 9999px;
    
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', Menlo, Consolas, monospace;
    
    --transition-fast: 150ms ease-out;
    --transition-normal: 200ms ease-out;
}

/* Reset & Base Elements */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    background-color: var(--canvas);
    color: var(--text-primary);
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    background-color: var(--canvas);
    color: var(--text-secondary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-feature-settings: "calt", "kern", "liga", "cv02", "cv03", "cv04", "cv11";
    overflow-x: hidden;
}

/* Accessible Focus Ring (R-32) */
:focus-visible {
    outline: 2px solid var(--accent-red);
    outline-offset: 2px;
}

/* Global Container & Section Spacing */
.container {
    width: 100%;
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 5rem 0;
}

/* Header & Navigation */
.site-header {
    position: sticky;
    top: 0;
    width: 100%;
    background-color: rgba(7, 8, 10, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--hairline);
    z-index: 100;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.nav-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.95rem;
    letter-spacing: -0.01em;
}

.brand-monogram {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    background-color: var(--surface-elevated);
    border: 1px solid var(--hairline-strong);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 700;
}

.nav-menu {
    display: flex;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 1.5rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    padding: 0.35rem 0.5rem;
    border-radius: var(--radius-sm);
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-link:hover {
    color: var(--text-primary);
    background-color: var(--surface-hover);
}

.nav-link.active {
    color: var(--text-primary);
}

/* Command Trigger Button */
.command-trigger {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background-color: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--text-secondary);
    padding: 0.35rem 0.75rem;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    min-height: 36px;
}

.command-trigger:hover {
    background-color: var(--surface-elevated);
    border-color: var(--hairline-strong);
    color: var(--text-primary);
}

.hotkey-badge {
    display: inline-flex;
    gap: 0.2rem;
}

kbd {
    display: inline-block;
    padding: 0.1rem 0.35rem;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    line-height: 1;
    color: var(--text-secondary);
    background-color: var(--surface-elevated);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-sm);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.65rem 1.25rem;
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-pill);
    border: 1px solid transparent;
    cursor: pointer;
    min-height: 44px;
    transition: all var(--transition-fast);
}

.btn-primary {
    background-color: var(--text-primary);
    color: #000000;
    font-weight: 600;
}

.btn-primary:hover {
    background-color: #e5e5e5;
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: var(--surface-card);
    border-color: var(--hairline);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background-color: var(--surface-elevated);
    border-color: var(--hairline-strong);
    transform: translateY(-1px);
}

.btn-ghost {
    background-color: transparent;
    color: var(--text-secondary);
}

.btn-ghost:hover {
    color: var(--text-primary);
    background-color: var(--surface-hover);
}

.btn-sm {
    padding: 0.4rem 0.85rem;
    font-size: 0.825rem;
    min-height: 36px;
}

/* Hero Section */
.hero-section {
    padding: 6rem 0 4rem;
}

.hero-container {
    max-width: 820px;
}

.status-indicator {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    padding: 0.3rem 0.85rem;
    border-radius: var(--radius-pill);
    margin-bottom: 1.75rem;
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--accent-green);
    box-shadow: 0 0 8px rgba(52, 211, 153, 0.4);
}

.status-label {
    font-size: 0.825rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.hero-title {
    font-size: 2.75rem;
    line-height: 1.15;
    font-weight: 600;
    letter-spacing: -0.025em;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.15rem;
    line-height: 1.65;
    color: var(--text-secondary);
    margin-bottom: 2.25rem;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.85rem;
    align-items: center;
}

/* Section Header Typography */
.section-header {
    margin-bottom: 2.5rem;
}

.section-tag {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent-red);
    margin-bottom: 0.5rem;
}

.section-title {
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.section-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    max-width: 640px;
}

/* Project Filter Controls */
.filter-group {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1.25rem;
}

.filter-btn {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    color: var(--text-secondary);
    padding: 0.35rem 0.85rem;
    border-radius: var(--radius-pill);
    font-family: inherit;
    font-size: 0.825rem;
    font-weight: 500;
    cursor: pointer;
    min-height: 36px;
    transition: all var(--transition-fast);
}

.filter-btn:hover {
    color: var(--text-primary);
    border-color: var(--hairline-strong);
    background-color: var(--surface-elevated);
}

.filter-btn.active {
    background-color: var(--accent-red-soft);
    border-color: rgba(255, 97, 97, 0.4);
    color: var(--accent-red);
    font-weight: 600;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.project-card {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-md);
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.project-card:hover {
    transform: translateY(-2px);
    border-color: var(--hairline-strong);
    background-color: var(--surface-elevated);
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.85rem;
}

.project-type {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.project-status {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--accent-green);
    background-color: var(--accent-green-soft);
    padding: 0.15rem 0.5rem;
    border-radius: var(--radius-pill);
}

.project-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.01em;
    margin-bottom: 0.65rem;
}

.project-description {
    font-size: 0.925rem;
    line-height: 1.55;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    flex-grow: 1;
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 1.25rem;
}

.tech-tag {
    font-family: var(--font-mono);
    font-size: 0.725rem;
    color: var(--text-secondary);
    background-color: var(--surface);
    border: 1px solid var(--hairline);
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-sm);
}

.project-footer {
    padding-top: 0.75rem;
    border-top: 1px solid var(--hairline);
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    color: var(--text-primary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.project-link:hover {
    color: var(--accent-red);
}

/* Empty State (R-27) */
.projects-empty-state {
    text-align: center;
    padding: 4rem 1.5rem;
    background-color: var(--surface-card);
    border: 1px dashed var(--hairline);
    border-radius: var(--radius-md);
}

.projects-empty-state[hidden] {
    display: none;
}

.empty-icon {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background-color: var(--surface-elevated);
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.empty-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.35rem;
}

.empty-description {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
}

/* Technical Skills Layout */
.skills-layout {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.skill-category {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-md);
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
}

.category-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.category-number {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-red);
}

.category-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
}

.category-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    line-height: 1.5;
}

.skill-badges {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.skill-badges li {
    font-size: 0.85rem;
    color: var(--text-primary);
    background-color: var(--surface);
    border: 1px solid var(--hairline);
    padding: 0.45rem 0.75rem;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
}

.skill-badges li::before {
    content: "•";
    color: var(--accent-red);
    font-weight: bold;
    display: inline-block;
    width: 1em;
}

/* About Section */
.about-card {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-md);
    padding: 2.5rem;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2.5rem;
    align-items: center;
}

.about-title {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    letter-spacing: -0.015em;
}

.about-text {
    font-size: 0.975rem;
    line-height: 1.65;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.about-metrics {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    background-color: var(--surface);
    border: 1px solid var(--hairline);
    padding: 1.5rem;
    border-radius: var(--radius-md);
}

.metric-item {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}

.metric-label {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.metric-value {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* Contact Section */
.contact-box {
    background-color: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-md);
    padding: 3rem 2rem;
    text-align: center;
    max-width: 720px;
    margin: 0 auto;
}

.contact-title {
    font-size: 2rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    letter-spacing: -0.02em;
}

.contact-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 520px;
    margin-left: auto;
    margin-right: auto;
}

.contact-actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
}

/* Footer */
.site-footer {
    border-top: 1px solid var(--hairline);
    padding: 2.5rem 0;
    background-color: var(--canvas);
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-copy {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.footer-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.85rem;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--text-primary);
}

.footer-shortcut-trigger {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-family: inherit;
    font-size: 0.85rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    transition: color var(--transition-fast);
}

.footer-shortcut-trigger:hover {
    color: var(--text-primary);
}

/* Command Palette Dialog (Raycast Style) */
.command-dialog {
    border: none;
    background: transparent;
    padding: 0;
    max-width: 600px;
    width: 90%;
    margin: auto;
    border-radius: var(--radius-lg);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.75);
    z-index: 1000;
}

.command-dialog::backdrop {
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}

.command-box {
    background-color: var(--surface);
    border: 1px solid var(--hairline-strong);
    border-radius: var(--radius-lg);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.command-input-wrapper {
    display: flex;
    align-items: center;
    padding: 0.85rem 1.25rem;
    border-bottom: 1px solid var(--hairline);
    gap: 0.75rem;
    background-color: var(--surface-card);
}

.command-search-icon {
    color: var(--text-muted);
    flex-shrink: 0;
}

.command-input {
    flex-grow: 1;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.95rem;
    outline: none;
}

.command-input::placeholder {
    color: var(--text-muted);
}

.command-close-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
}

.command-results {
    max-height: 340px;
    overflow-y: auto;
    padding: 0.75rem;
}

.command-group {
    margin-bottom: 0.75rem;
}

.command-group:last-child {
    margin-bottom: 0;
}

.command-group-title {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 0.35rem 0.6rem;
}

.command-item {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    padding: 0.6rem 0.75rem;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.875rem;
    cursor: pointer;
    text-align: left;
    transition: all var(--transition-fast);
    min-height: 40px;
}

.command-item:hover, .command-item.selected {
    background-color: var(--surface-hover);
    border-color: var(--hairline);
}

.command-item:focus-visible {
    background-color: var(--surface-hover);
    border-color: var(--accent-red);
    outline: none;
}

.command-item-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.command-item-hint {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.command-footer {
    padding: 0.65rem 1.25rem;
    border-top: 1px solid var(--hairline);
    background-color: var(--surface-card);
}

.command-tip {
    font-size: 0.75rem;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 0.35rem;
    flex-wrap: wrap;
}

/* Toast Notification (R-26 User Feedback) */
.toast-container {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    z-index: 2000;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toast {
    background-color: var(--surface-elevated);
    color: var(--text-primary);
    border: 1px solid var(--hairline-strong);
    padding: 0.75rem 1.25rem;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.6);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    pointer-events: auto;
    animation: toastIn 180ms ease-out forwards;
}

@keyframes toastIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes toastOut {
    from {
        opacity: 1;
        transform: translateY(0);
    }
    to {
        opacity: 0;
        transform: translateY(10px);
    }
}

/* Responsive Breakpoints (R-03 Mobile Perfect) */
@media (max-width: 900px) {
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .skills-layout {
        grid-template-columns: 1fr;
    }
    
    .about-card {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        padding: 1.75rem;
    }
}

@media (max-width: 640px) {
    .site-header {
        padding: 0;
    }
    
    .nav-list {
        display: none; /* Accessible via Command Palette on Mobile */
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-description {
        font-size: 1rem;
    }
    
    .section {
        padding: 3.5rem 0;
    }
    
    .contact-title {
        font-size: 1.6rem;
    }
    
    .command-trigger-text {
        display: none;
    }
    
    .footer-container {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}