/* Tartalon Brand Website Stylesheet */

/* ===== CSS CUSTOM PROPERTIES ===== */
:root {
    --bg-primary: #0D1117;
    --bg-secondary: #161B22;
    --bg-surface: #1C2128;
    --border: #30363D;
    --accent: #00D4FF;
    --accent-glow: rgba(0, 212, 255, 0.15);
    --accent-secondary: #FF8C42;
    --text-primary: #F5F5F5;
    --text-secondary: #C9D1D9;
    --text-muted: #8B949E;
    --radius: 8px;
    --radius-lg: 12px;
    --max-width: 1200px;
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    --transition: 0.2s ease;
    --transition-slow: 0.4s ease;
}

/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    background: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
}
h1 { font-size: clamp(3rem, 8vw, 5.5rem); font-weight: 800; }
h2 { font-size: clamp(2rem, 5vw, 3rem); font-weight: 700; }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.5rem); font-weight: 600; }
p { color: var(--text-secondary); max-width: 70ch; }

/* ===== CONTAINER ===== */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin-inline: auto;
    padding-inline: clamp(1rem, 4vw, 3rem);
}

/* ===== SECTION SHARED ===== */
.section { padding-block: clamp(4rem, 8vw, 7rem); }
.section-header { margin-bottom: 3rem; }
.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 0.75rem;
    padding: 0.35rem 0.75rem;
    border: 1px solid var(--accent);
    border-radius: 99px;
}
.section-title { margin-bottom: 0.75rem; }
.section-subtitle { font-size: 1.1rem; color: var(--text-muted); }
.section-footer { margin-top: 3rem; text-align: center; }

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.6rem;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: var(--radius);
    border: 1px solid transparent;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}
.btn--primary {
    background: var(--accent);
    color: var(--bg-primary);
    border-color: var(--accent);
    font-weight: 700;
}
.btn--primary:hover {
    background: #33e0ff;
    border-color: #33e0ff;
    box-shadow: 0 0 30px var(--accent-glow);
}
.btn--outline {
    background: transparent;
    color: var(--text-primary);
    border-color: var(--border);
}
.btn--outline:hover {
    border-color: var(--text-secondary);
    background: var(--bg-secondary);
}

/* ===== TAGS ===== */
.tag {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent);
    background: rgba(0,212,255,0.08);
    padding: 0.3rem 0.7rem;
    border-radius: 6px;
}

/* ===== NAVBAR ===== */
.navbar {
    position: fixed;
    inset-block-start: 0;
    inset-inline: 0;
    z-index: 1000;
    background: rgba(13, 17, 23, 0.85);
    border-bottom: 1px solid transparent;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: var(--transition);
}
.navbar.scrolled { border-bottom-color: var(--border); }
.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--max-width);
    margin-inline: auto;
    padding-block: 1rem;
    padding-inline: clamp(1rem, 4vw, 3rem);
}
.nav-logo {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: 0.15em;
    color: var(--text-primary);
}
.nav-logo:hover { color: var(--accent); }

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
    list-style: none;
}
.nav-link {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
}
.nav-link:hover, .nav-link.active { color: var(--text-primary); }
.nav-link--accent {
    color: var(--accent);
    padding: 0.5rem 1rem;
    border: 1px solid rgba(0,212,255,0.4);
    border-radius: var(--radius);
    transition: var(--transition);
}
.nav-link--accent:hover { background: var(--accent); color: var(--bg-primary); border-color: var(--accent); }

.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 0.5rem; }
.nav-toggle-bar {
    display: block; width: 24px; height: 2px; background: var(--text-primary);
    border-radius: 2px; transition: var(--transition); transform-origin: center;
}
.nav-toggle-bar + .nav-toggle-bar { margin-top: 5px; }

/* ===== HERO ===== */
.hero {
    position: relative;
    min-height: 100svh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding-block: 6rem 4rem;
}
.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 50% 30%, rgba(0,212,255,0.06) 0%, transparent 60%),
        radial-gradient(ellipse at 80% 80%, rgba(255,140,66,0.04) 0%, transparent 50%),
        var(--bg-primary);
    z-index: 0;
}
.hero-content {
    position: relative; z-index: 1;
    text-align: center;
    max-width: 800px;
    padding-inline: 2rem;
}
.hero-label {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 2rem;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border);
    border-radius: 99px;
    background: var(--bg-secondary);
}
.hero-label-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    background: #3FB950;
    box-shadow: 0 0 10px rgba(63,185,80,0.5);
    animation: pulse-dot 2s infinite;
}
@keyframes pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(0.85); }
}
.hero-title {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    text-shadow: 0 0 60px rgba(0,212,255,0.2);
}
.hero-subtitle {
    font-size: clamp(1.15rem, 2vw, 1.5rem);
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}
.hero-description {
    font-size: 1rem;
    color: var(--text-muted);
    margin-inline: auto;
    margin-bottom: 2.5rem;
    line-height: 1.7;
}
.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
}
.hero-scroll {
    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;
    font-weight: 500;
    letter-spacing: 0.1em;
}
.hero-scroll-line {
    width: 1px; height: 40px;
    background: linear-gradient(to bottom, var(--accent), transparent);
    animation: scroll-line 2s infinite;
}
@keyframes scroll-line {
    0% { transform: scaleY(0); transform-origin: top; }
    50% { transform: scaleY(1); transform-origin: top; }
    51% { transform: scaleY(1); transform-origin: bottom; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ===== EXPERIMENTS ===== */
.experiments { background: var(--bg-secondary); }
.experiments-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.25rem;
}
.experiment-card {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: var(--transition);
}
.experiment-card:hover {
    border-color: var(--accent);
    box-shadow: 0 0 30px rgba(0,212,255,0.08);
    background: #21262d;
}
.experiment-card-header {
    display: flex; align-items: center; gap: 0.5rem;
}
.status-dot {
    width: 8px; height: 8px; border-radius: 50%;
}
.status-dot--building { background: #3FB950; box-shadow: 0 0 8px rgba(63,185,80,0.5); }
.status-dot--testing { background: var(--accent); }
.status-dot--researching { background: var(--accent-secondary); }
.status-text { font-size: 0.75rem; color: var(--text-muted); font-weight: 500; letter-spacing: 0.05em; text-transform: uppercase; }
.experiment-card-title { color: var(--text-primary); }
.experiment-card-desc { font-size: 0.9rem; color: var(--text-muted); }
.experiment-card-tags { display: flex; gap: 0.5rem; margin-top: auto; padding-top: 0.5rem; }

/* ===== AREAS GRID ===== */
.areas-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}
.area-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    transition: var(--transition);
}
.area-card:hover {
    border-color: var(--accent);
    box-shadow: 0 0 25px rgba(0,212,255,0.08);
}
.area-card-icon {
    color: var(--accent);
    margin-bottom: 1rem;
}
.area-card-icon svg { width: 28px; height: 28px; }
.area-card-title { color: var(--text-primary); margin-bottom: 0.35rem; }
.area-card-desc { font-size: 0.85rem; color: var(--text-muted); }

/* ===== PROJECTS ===== */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}
.project-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: var(--transition);
}
.project-card:hover {
    border-color: rgba(0,212,255,0.5);
    box-shadow: 0 0 30px rgba(0,212,255,0.08);
}
.project-card-image {
    width: 100%;
    aspect-ratio: 16 / 10;
    display: flex; align-items: center; justify-content: center;
}
.project-card-placeholder { color: var(--accent); opacity: 0.6; }
.project-card-placeholder svg { width: 64px; height: 64px; }
.project-card-content {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    flex: 1;
}
.project-card-meta { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.project-card-title { color: var(--text-primary); }
.project-card-desc { font-size: 0.9rem; color: var(--text-muted); }
.project-card-link {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
    margin-top: auto;
    transition: var(--transition);
}
.project-card:hover .project-card-link { gap: 0.75rem; }
.project-card-link::after { content: '→'; margin-left: 0.25rem; transition: margin 0.2s; }
.project-card:hover .project-card-link::after { margin-left: 0.75rem; }

/* ===== BUILD LOGS ===== */
.build-logs-list {
    display: flex;
    flex-direction: column;
    gap: 0;
    border-left: 1px solid var(--border);
    padding-left: 1.5rem;
}
.build-log-entry {
    display: flex;
    gap: 1.5rem;
    padding-block: 1.5rem;
    position: relative;
    transition: var(--transition);
}
.build-log-entry::before {
    content: '';
    position: absolute;
    left: -1.65rem; top: 2rem;
    width: 8px; height: 8px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 12px rgba(0,212,255,0.4);
    border: 2px solid var(--bg-primary);
}
.build-log-date {
    min-width: 70px;
    font-weight: 700;
    color: var(--text-muted);
    padding-top: 0.25rem;
}
.build-log-day { display: block; font-size: 1.25rem; color: var(--text-primary); }
.build-log-month { display: block; font-size: 0.8rem; color: var(--accent); letter-spacing: 0.1em; text-transform: uppercase; }
.build-log-content { flex: 1; }
.build-log-categories { display: flex; gap: 0.5rem; margin-bottom: 0.5rem; }
.build-log-title { color: var(--text-primary); margin-bottom: 0.5rem; transition: var(--transition); }
.build-log-entry:hover .build-log-title { color: var(--accent); }
.build-log-excerpt { font-size: 0.9rem; color: var(--text-muted); }

/* ===== ARTICLES ===== */
.articles { background: var(--bg-secondary); }
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}
.article-card {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: var(--transition);
}
.article-card:hover {
    border-color: rgba(0,212,255,0.5);
    transform: translateY(-2px);
}
.article-card-meta { display: flex; justify-content: space-between; align-items: center; }
.article-read-time {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
}
.article-card-title { color: var(--text-primary); transition: var(--transition); }
.article-card:hover .article-card-title { color: var(--accent); }
.article-card-excerpt { font-size: 0.9rem; color: var(--text-muted); }
.article-card-date { font-size: 0.8rem; color: var(--text-muted); margin-top: auto; }

/* ===== PHILOSOPHY ===== */
.philosophy { background: var(--bg-primary); }
.philosophy-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}
.philosophy-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    transition: var(--transition);
}
.philosophy-card:hover {
    border-color: var(--accent);
    box-shadow: 0 0 25px rgba(0,212,255,0.08);
}
.philosophy-card h3 { color: var(--accent); margin-bottom: 0.5rem; }
.philosophy-card p { font-size: 0.9rem; color: var(--text-muted); }

/* ===== CONTACT ===== */
.contact { background: var(--bg-secondary); }
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
}
.contact-card {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    transition: var(--transition);
}
.contact-card:hover {
    border-color: var(--accent);
    background: #21262d;
}
.contact-card-icon {
    color: var(--accent);
    margin-bottom: 0.75rem;
}
.contact-card-icon svg { width: 24px; height: 24px; }
.contact-card-title { color: var(--text-primary); margin-bottom: 0.25rem; }
.contact-card-detail { font-size: 0.9rem; color: var(--text-muted); }

/* ===== PROJECTS MEGA LIST ===== */
.projects-mega { display: flex; flex-direction: column; gap: 1rem; }
.project-panel { background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; transition: var(--transition); }
.project-panel:hover { border-color: rgba(0,212,255,0.5); }
.project-panel-header { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1.5rem; }
.project-panel-header h2 { color: var(--text-primary); margin-top: 0.5rem; }
.project-panel-meta { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.project-panel-summary { font-size: 0.95rem; color: var(--text-secondary); padding: 0 1.5rem; cursor: pointer; outline: none; user-select: none; }
.project-panel-body { display: none; color: var(--text-secondary); padding: 0 1.5rem 1.5rem; }
.project-panel-body > * + * { margin-top: 0.6rem; }
.project-chevron { display: inline-block; transition: transform 0.2s ease; color: var(--accent); font-size: 1.25rem; }
.project-panel-placeholder { margin-top: 1rem; color: var(--text-muted); background: var(--bg-primary); border: 1px dashed var(--border); border-radius: var(--radius); padding: 1.25rem; text-align: center; font-size: 0.85rem; }

/* ===== FOOTER ===== */
.footer { border-top: 1px solid var(--border); padding-block: 3rem; }
.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 2rem;
}
.footer-logo {
    font-size: 1.1rem;
    font-weight: 800;
    letter-spacing: 0.15em;
    color: var(--text-primary);
}
.footer-tagline { font-size: 0.85rem; color: var(--text-muted); margin-top: 0.5rem; }
.footer-links { display: flex; gap: 2rem; }
.footer-links a {
    font-size: 0.85rem;
    color: var(--text-muted);
    transition: var(--transition);
    font-weight: 500;
}
.footer-links a:hover { color: var(--accent); }
.footer-bottom {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}
.footer-bottom p { font-size: 0.8rem; color: var(--text-muted); }

/* ===== ANIMATIONS ===== */
.fade-in { opacity: 0; transform: translateY(20px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .nav-toggle { display: block; z-index: 1001; }
    .nav-menu {
        position: fixed;
        inset: 0;
        background: rgba(13,17,23,0.98);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2rem;
        opacity: 0;
        visibility: hidden;
        transition: var(--transition-slow);
        backdrop-filter: blur(20px);
    }
    .nav-menu.open { opacity: 1; visibility: visible; }
    .nav-toggle.open .nav-toggle-bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
    .nav-toggle.open .nav-toggle-bar:nth-child(2) { opacity: 0; }
    .nav-toggle.open .nav-toggle-bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

    .hero-actions { flex-direction: column; align-items: center; }
    .projects-grid { grid-template-columns: 1fr; }
    .articles-grid { grid-template-columns: 1fr; }
    .build-log-entry { flex-direction: column; gap: 0.5rem; }
    .build-logs-list { padding-left: 1rem; }
}

@media (max-width: 480px) {
    .area-card { padding: 1rem; }
    .contact-grid { grid-template-columns: 1fr; }
}