/* ================================================
   Tim Hanewich — Personal Portfolio
   Bold & Techy Dark Theme
   ================================================ */

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

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* --- CSS Variables --- */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #111118;
    --bg-card: #141420;
    --bg-card-hover: #1a1a2a;
    --accent-cyan: #00d4ff;
    --accent-purple: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, #00d4ff, #8b5cf6);
    --text-primary: #e4e4e7;
    --text-secondary: #a1a1aa;
    --text-muted: #52525b;
    --border-color: #1e1e2e;
    --border-hover: #2e2e3e;
    --cat-ai: #00d4ff;
    --cat-robotics: #10b981;
    --cat-finance: #f59e0b;
    --cat-iot: #f97316;
    --cat-microsoft: #3b82f6;
    --cat-software: #a855f7;
    --cat-gaming: #ec4899;
}

a {
    color: var(--accent-cyan);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #fff;
}

::selection {
    background: rgba(0, 212, 255, 0.3);
    color: #fff;
}

/* --- Sidebar (fixed, appears on scroll) --- */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: 200px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.15rem;
    padding: 2rem 1.25rem;
    z-index: 500;
    background: var(--bg-primary);
    border-right: 1px solid var(--border-color);
    box-shadow: 4px 0 25px rgba(0, 0, 0, 0.35);
    opacity: 0;
    transform: translateX(-100%);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    pointer-events: none;
}

.sidebar.visible {
    opacity: 1;
    transform: translateX(0);
    pointer-events: auto;
}

.sidebar-avatar {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    border: 2px solid var(--border-color);
    margin-bottom: 0.85rem;
    object-fit: cover;
    box-shadow: 0 0 20px rgba(0, 212, 255, 0.1);
}

.sidebar-name {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.01em;
}

.sidebar-role {
    font-size: 0.72rem;
    color: var(--text-muted);
    text-align: center;
    margin-bottom: 1.15rem;
    line-height: 1.4;
}

.sidebar-links {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    justify-content: center;
}

.sidebar-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
    transition: all 0.25s ease;
    background: rgba(20, 20, 32, 0.4);
}

.sidebar-links a:hover {
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
    transform: translateY(-2px);
    box-shadow: 0 3px 10px rgba(0, 212, 255, 0.15);
}

@media (max-width: 1024px) {
    .sidebar {
        display: none;
    }
}

/* --- Navigation --- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1.1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.35s ease;
}

.nav.scrolled {
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    padding: 0.75rem 2rem;
}

.nav-logo {
    font-size: 1.3rem;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
    text-decoration: none;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-primary);
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    z-index: 1001;
}

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 2rem 4rem;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: -50%;
    width: 200%;
    height: 200%;
    background:
        radial-gradient(circle at 20% 40%, rgba(0, 212, 255, 0.1) 0%, transparent 40%),
        radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.1) 0%, transparent 40%),
        radial-gradient(circle at 50% 90%, rgba(16, 185, 129, 0.06) 0%, transparent 40%);
    animation: meshFloat 15s ease-in-out infinite alternate;
}

@keyframes meshFloat {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(-3%, -2%) scale(1.05); }
    100% { transform: translate(2%, -4%) scale(1.02); }
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
}

.hero-avatar {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    border: 3px solid var(--border-color);
    margin-bottom: 1.5rem;
    object-fit: cover;
    box-shadow: 0 0 40px rgba(0, 212, 255, 0.12);
    transition: box-shadow 0.4s ease;
}

.hero-avatar:hover {
    box-shadow: 0 0 50px rgba(0, 212, 255, 0.25);
}

.hero-name {
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1rem;
}

.hero-name .gradient {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-tagline {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.hero-bio {
    font-size: 1.05rem;
    color: var(--text-muted);
    max-width: 620px;
    margin: 0 auto 2rem;
    line-height: 1.75;
}

/* Social Icons */
.social-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 1.2rem;
    transition: all 0.3s ease;
    background: rgba(20, 20, 32, 0.5);
}

.social-links a:hover {
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 212, 255, 0.15);
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    font-size: 0.7rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    animation: bobDown 2.5s ease-in-out infinite;
}

@keyframes bobDown {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

/* --- Section Shared --- */
.section {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    letter-spacing: -0.02em;
}

.section-subtitle {
    color: var(--text-secondary);
    font-size: 1.05rem;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.7;
}

.section-line {
    width: 60px;
    height: 3px;
    background: var(--accent-gradient);
    border-radius: 2px;
    margin: 1.25rem auto 0;
}

/* --- About Section --- */
.about-text {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 750px;
    margin: 0 auto 2.5rem;
    line-height: 1.8;
}

.about-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
    max-width: 850px;
    margin: 0 auto;
}

.about-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 1.75rem 1.25rem;
    text-align: center;
    transition: all 0.3s ease;
}

.about-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.25);
}

.about-card-icon {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.about-card-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.35rem;
    color: var(--text-primary);
}

.about-card-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* --- Project Filters --- */
.filter-bar {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 2.5rem;
}

.filter-btn {
    padding: 0.5rem 1.25rem;
    border-radius: 100px;
    border: 1px solid var(--border-color);
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: inherit;
}

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

.filter-btn.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: #fff;
    box-shadow: 0 2px 12px rgba(0, 212, 255, 0.2);
}

/* --- Project Cards --- */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 1.25rem;
}

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    text-decoration: none;
    color: inherit;
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--card-accent, var(--accent-gradient));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.project-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: 0 10px 35px rgba(0, 0, 0, 0.35);
    background: var(--bg-card-hover);
}

.project-card:hover::before {
    opacity: 1;
}

.project-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.75rem;
}

.project-tag {
    font-size: 0.68rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0.2rem 0.65rem;
    border-radius: 5px;
}

.project-tag[data-cat="ai"] { background: rgba(0, 212, 255, 0.1); color: var(--cat-ai); }
.project-tag[data-cat="robotics"] { background: rgba(16, 185, 129, 0.1); color: var(--cat-robotics); }
.project-tag[data-cat="finance"] { background: rgba(245, 158, 11, 0.1); color: var(--cat-finance); }
.project-tag[data-cat="iot"] { background: rgba(249, 115, 22, 0.1); color: var(--cat-iot); }
.project-tag[data-cat="microsoft"] { background: rgba(59, 130, 246, 0.1); color: var(--cat-microsoft); }
.project-tag[data-cat="software"] { background: rgba(168, 85, 247, 0.1); color: var(--cat-software); }
.project-tag[data-cat="gaming"] { background: rgba(236, 72, 153, 0.1); color: var(--cat-gaming); }

.project-year {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
    font-variant-numeric: tabular-nums;
}

.project-card-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    line-height: 1.3;
}

.project-card-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.65;
    flex: 1;
}

.project-card-footer {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 1rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-color);
    font-size: 0.8rem;
    color: var(--text-muted);
    transition: color 0.2s;
}

.project-card:hover .project-card-footer {
    color: var(--accent-cyan);
}

.project-card-footer i {
    font-size: 0.9rem;
}

/* Card glow per category */
.project-card[data-category="ai"] { --card-accent: var(--cat-ai); }
.project-card[data-category="robotics"] { --card-accent: var(--cat-robotics); }
.project-card[data-category="finance"] { --card-accent: var(--cat-finance); }
.project-card[data-category="iot"] { --card-accent: var(--cat-iot); }
.project-card[data-category="microsoft"] { --card-accent: var(--cat-microsoft); }
.project-card[data-category="software"] { --card-accent: var(--cat-software); }
.project-card[data-category="gaming"] { --card-accent: var(--cat-gaming); }

.project-card[data-category="ai"]:hover { box-shadow: 0 10px 35px rgba(0, 212, 255, 0.1); }
.project-card[data-category="robotics"]:hover { box-shadow: 0 10px 35px rgba(16, 185, 129, 0.1); }
.project-card[data-category="finance"]:hover { box-shadow: 0 10px 35px rgba(245, 158, 11, 0.1); }
.project-card[data-category="iot"]:hover { box-shadow: 0 10px 35px rgba(249, 115, 22, 0.1); }
.project-card[data-category="microsoft"]:hover { box-shadow: 0 10px 35px rgba(59, 130, 246, 0.1); }
.project-card[data-category="software"]:hover { box-shadow: 0 10px 35px rgba(168, 85, 247, 0.1); }
.project-card[data-category="gaming"]:hover { box-shadow: 0 10px 35px rgba(236, 72, 153, 0.1); }

/* --- Writings Section --- */
.writings-section {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 6rem 2rem;
}

.writings-section .section-header {
    max-width: 1200px;
    margin: 0 auto 3rem;
}

.writings-cta {
    text-align: center;
    margin-top: 2.5rem;
}

/* --- Article List --- */
.articles-list {
    max-width: 750px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
}

.articles-loading {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    padding: 2rem;
}

.article-item {
    display: flex;
    align-items: center;
    gap: 1.25rem;
    padding: 1.15rem 1rem;
    border-bottom: 1px solid var(--border-color);
    text-decoration: none;
    color: inherit;
    transition: all 0.25s ease;
    position: relative;
    overflow: hidden;
    background-size: cover;
    background-position: center;
    border-radius: 8px;
}

.article-item::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, var(--bg-secondary) 35%, rgba(17, 17, 24, 0.75) 70%, rgba(17, 17, 24, 0.55) 100%);
    z-index: 0;
    transition: all 0.3s ease;
}

.article-item:hover::before {
    background: linear-gradient(90deg, var(--bg-secondary) 25%, rgba(17, 17, 24, 0.65) 60%, rgba(17, 17, 24, 0.4) 100%);
}

.article-item > * {
    position: relative;
    z-index: 1;
}

.article-item:first-child {
    border-top: 1px solid var(--border-color);
}

.article-item:hover {
    padding-left: 1.25rem;
}

.article-item:hover .article-title {
    color: var(--accent-cyan);
}

.article-date {
    font-size: 0.78rem;
    color: var(--text-muted);
    font-weight: 500;
    white-space: nowrap;
    min-width: 90px;
    font-variant-numeric: tabular-nums;
}

.article-body {
    flex: 1;
    min-width: 0;
}

.article-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    transition: color 0.2s;
}

.article-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin-top: 0.4rem;
}

.article-tag {
    font-size: 0.62rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.12rem 0.5rem;
    border-radius: 4px;
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
}

.article-arrow {
    color: var(--text-muted);
    font-size: 0.8rem;
    transition: all 0.25s ease;
    flex-shrink: 0;
}

.article-item:hover .article-arrow {
    color: var(--accent-cyan);
    transform: translateX(4px);
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.8rem 2rem;
    background: var(--accent-gradient);
    color: #fff;
    border: none;
    border-radius: 100px;
    font-size: 0.95rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(0, 212, 255, 0.3);
    color: #fff;
}

/* --- Footer --- */
.footer {
    padding: 3rem 2rem;
    text-align: center;
    border-top: 1px solid var(--border-color);
    background: var(--bg-primary);
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.footer-links a {
    color: var(--text-muted);
    font-size: 1.15rem;
    transition: all 0.2s;
}

.footer-links a:hover {
    color: var(--accent-cyan);
    transform: translateY(-2px);
}

.footer p {
    color: var(--text-muted);
    font-size: 0.8rem;
    letter-spacing: 0.02em;
}

/* --- Scroll Reveal --- */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* --- Responsive: Tablet --- */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(10, 10, 15, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 2.5rem;
        z-index: 999;
    }

    .nav-links.open {
        display: flex;
    }

    .nav-links a {
        font-size: 1.3rem;
    }

    .nav-toggle {
        display: block;
    }

    .hero-name {
        font-size: 2.25rem;
    }

    .hero-tagline {
        font-size: 1rem;
    }

    .hero-bio {
        font-size: 0.95rem;
    }

    .hero-avatar {
        width: 100px;
        height: 100px;
    }

    .about-cards {
        grid-template-columns: 1fr;
        max-width: 400px;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .writings-section {
        padding: 4rem 1.25rem;
    }

    .section {
        padding: 4rem 1.25rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .filter-bar {
        gap: 0.4rem;
    }

    .filter-btn {
        font-size: 0.75rem;
        padding: 0.4rem 0.85rem;
    }

    .writings-inner {
        padding: 4rem 1.25rem;
    }
}

/* --- Responsive: Small Mobile --- */
@media (max-width: 480px) {
    .hero {
        padding: 5rem 1.25rem 3rem;
    }

    .hero-name {
        font-size: 1.85rem;
    }

    .hero-avatar {
        width: 85px;
        height: 85px;
    }

    .social-links {
        gap: 0.6rem;
    }

    .social-links a {
        width: 38px;
        height: 38px;
        font-size: 1rem;
        border-radius: 10px;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .project-card {
        padding: 1.25rem;
    }
}