/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html { scroll-behavior: smooth; }

/* Facebook-inspired theme tokens */
:root {
    --fb-blue: #1877F2;
    --fb-blue-hover: #166FE0;
    --fb-blue-dark: #0d4b8f;
    --fb-bg: #f0f2f5;
    --fb-bg-alt: #f5f7fa;
    --fb-surface: #ffffff;
    --fb-text: #1d2733;
    --fb-text-soft: #5a6c7d;
    --fb-border: #d9dee3;
    --fb-border-strong: #b8c2cc;
    --fb-focus: #1B74E4;
    --fb-radius-lg: 14px;
    --fb-shadow-sm: 0 2px 6px -1px rgba(0,0,0,0.08);
    --fb-shadow: 0 6px 18px -4px rgba(0,0,0,0.10);
    --fb-shadow-hover: 0 14px 36px -10px rgba(0,0,0,0.25);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.55;
    color: var(--fb-text);
    background: var(--fb-bg);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* Headings use Work Sans for brand-like weight & shape */
h1, h2, h3, .hero-title, .site-title {
    font-family: 'Work Sans', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    font-weight: 700;
    letter-spacing: -0.5px;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header */
.header { background: rgba(255,255,255,0.92); backdrop-filter: blur(12px) saturate(1.25); border-bottom:1px solid var(--fb-border); position:fixed; top:0; left:0; right:0; z-index:1000; box-shadow:0 2px 12px -2px rgba(0,0,0,0.08); }

 .nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.8rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
    gap: 2rem;
 }

/* Cluster (links + icon) on right */
.nav-cluster {
    display: flex;
    align-items: center;
    gap: 1.75rem;
}

.nav-divider {
    width: 1px;
    height: 28px;
    background: linear-gradient(to bottom, rgba(0,0,0,0.08), rgba(0,0,0,0.15));
    border-radius: 1px;
}

.nav-brand .site-title { font-size:1.45rem; font-weight:700; color:var(--fb-blue-dark); letter-spacing:-0.45px; }

.brand-link { text-decoration:none; color:var(--fb-blue-dark); position:relative; transition:color .25s ease; }
.brand-link:hover { color: var(--fb-blue); }
.brand-link:focus-visible { outline:2px solid var(--fb-focus); outline-offset:4px; border-radius:4px; }

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

.nav-links a { text-decoration:none; color:var(--fb-text); font-weight:500; transition:color .25s ease; position:relative; }
.nav-links a:hover { color: var(--fb-blue); }

.nav-links a::after { content:''; position:absolute; bottom:-5px; left:0; width:0; height:2px; background: var(--fb-blue); transition:width .3s ease; }
.nav-links a:hover::after { width:100%; }

/* Active page/link state */
.nav-links a.active { color: var(--fb-blue); font-weight:600; }
.nav-links a.active::after { width:100%; }


/* Social link icon */
 .social-link { display:flex; align-items:center; justify-content:center; color: var(--fb-blue-dark); filter: grayscale(35%) brightness(.95); transition: color .3s ease, transform .3s ease, filter .4s ease; }

.social-link svg {
    display: block;
}

 .social-link:hover { color: var(--fb-blue); filter:none; transform:translateY(-2px); }

.social-link:focus-visible { outline:2px solid var(--fb-focus); outline-offset:4px; border-radius:4px; }

 .social-link-large svg { width: 40px; height: 40px; }
 .social-link-large { font-size: 2rem; }

/* Main content */
.main {
    margin-top: 80px;
}

/* Hero section */
 .hero { min-height:52vh; display:flex; align-items:center; justify-content:center; padding:3.5rem 0 3rem; text-align:center; background: linear-gradient(135deg, var(--fb-blue) 0%, var(--fb-blue-dark) 100%); position:relative; overflow:hidden; }

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000"><defs><radialGradient id="a" cx="50%" cy="50%"><stop offset="0%" stop-color="%23ffffff" stop-opacity="0.1"/><stop offset="100%" stop-color="%23ffffff" stop-opacity="0"/></radialGradient></defs><circle cx="500" cy="500" r="400" fill="url(%23a)"/></svg>') center/cover;
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
    padding: 0 2rem;
}

.hero-title { font-size:clamp(2.35rem,4.5vw,3.5rem); font-weight:700; color:#fff; margin-bottom:1.1rem; letter-spacing:-0.6px; text-shadow:0 2px 14px rgba(0,0,0,0.26); }

.hero-subtitle { font-size:clamp(1.05rem,2.2vw,1.25rem); color:rgba(255,255,255,0.9); margin-bottom:1.85rem; font-weight:500; letter-spacing:1.15px; text-transform:uppercase; }

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 0.9rem;
}

.btn-primary { background: var(--fb-blue); color:#fff; border:2px solid var(--fb-blue); box-shadow: var(--fb-shadow-sm); }
.btn-primary:hover { background: var(--fb-blue-hover); border-color: var(--fb-blue-hover); transform:translateY(-2px); box-shadow:0 8px 22px -6px rgba(0,0,0,0.28); }
.btn-secondary { background:#fff; color:var(--fb-blue-dark); border:2px solid var(--fb-blue); }
.btn-secondary:hover { background: var(--fb-blue); color:#fff; }

/* Minimal utility components */
.status-badge { display:inline-block; font-size:0.68rem; letter-spacing:1.1px; font-weight:600; text-transform:uppercase; background:#e8f1ff; color:var(--fb-blue-dark); padding:0.38rem 0.65rem 0.4rem; border-radius:999px; border:1px solid #b3cffb; box-shadow:0 1px 3px rgba(0,0,0,0.08); }
.status-badge[data-state="in-progress"] { background:#e8f1ff; border-color:#bcd6ff; color:var(--fb-blue-dark); }
.status-badge[data-state="beta-released"] { background:#d4f4dd; border-color:#86d293; color:#0a5f1f; }
.watch-note { font-size: 0.85rem; color:#4a5b68; opacity:0.9; }

/* Utilities */
.intent-list { max-width:700px; margin:1.5rem auto 2.5rem; line-height:1.6; color:#4a5b68; font-size:0.95rem; }
.mt-gap-lg { margin-top:2rem !important; }

/* Sections */
.about, .projects, .contact {
    padding: 5rem 0;
    background: white;
}

.about { background: linear-gradient(145deg,#ffffff 0%, var(--fb-bg-alt) 100%); }

.projects { background:#f3f5f8; }

.contact { background: linear-gradient(145deg,#ffffff 0%, var(--fb-bg-alt) 100%); }

section h2 { font-size:2.5rem; font-weight:700; color:var(--fb-blue-dark); margin-bottom:2rem; text-align:center; position:relative; }

section h2::after { content:''; position:absolute; bottom:-10px; left:50%; transform:translateX(-50%); width:64px; height:3px; background: linear-gradient(90deg, var(--fb-blue), var(--fb-blue-dark)); border-radius:2px; }

section p { font-size:1.05rem; color:var(--fb-text-soft); text-align:center; max-width:640px; margin:0 auto 2rem; line-height:1.75; }

/* Projects grid */
.projects-grid {
    display: grid;
    gap: 2rem;
    margin-top: 3rem;
}

/* Desktop: enforce exactly 3 tiles */
@media (min-width: 900px) {
    .projects-grid { grid-template-columns: repeat(3, 1fr); }
}

.project-card { background:var(--fb-surface); padding:2rem; border-radius:var(--fb-radius-lg); box-shadow:var(--fb-shadow); transition:all .3s ease; border:1px solid var(--fb-border); display:flex; flex-direction:column; min-height:310px; }
.project-card:hover { transform:translateY(-8px); box-shadow:var(--fb-shadow-hover); border-color:var(--fb-blue); }

.project-card h3 { font-size:1.25rem; font-weight:600; color:var(--fb-text); margin-bottom:0.75rem; }

.project-card p { font-size:0.95rem; color:var(--fb-text-soft); text-align:left; margin:0; line-height:1.55; }

.card-actions {
    margin-top: auto; /* push to bottom */
    padding-top: 1.5rem;
    position: relative;
}

.btn-small {
    padding: 0.8rem 1.5rem;
    font-size: 0.85rem;
}

/* Fix button visibility within project cards */
.project-card .btn-primary { color:#fff; background:var(--fb-blue); border:2px solid var(--fb-blue); }
.project-card .btn-primary:hover { background:var(--fb-blue-hover); border-color:var(--fb-blue-hover); }

/* Back to projects button (reuse primary card style) */
.btn-back { background:#fff; color:var(--fb-blue-dark); border:2px solid var(--fb-blue); padding:0.85rem 2rem; font-size:0.78rem; letter-spacing:1px; font-weight:600; text-transform:uppercase; border-radius:50px; display:inline-block; text-decoration:none; transition:all .25s ease; }
.btn-back:hover,.btn-back:focus-visible { background:var(--fb-blue); border-color:var(--fb-blue); color:#ffffff; box-shadow:0 8px 26px -8px rgba(0,0,0,0.3); }

/* Contact section */
.contact-info {
    text-align: center;
    margin-top: 2rem;
}

/* Footer */
.footer { background:var(--fb-blue-dark); color:#fff; padding:2rem 0; text-align:center; }

.footer p { color:rgba(255,255,255,0.78); margin:0; }

.footer a.footer-link { color:#d2e3ff; text-decoration:none; margin-left:0.25rem; transition:color .25s ease; }
.footer a.footer-link:hover,.footer a.footer-link:focus-visible { color:#ffffff; text-decoration:underline; }

/* Responsive design */
@media (max-width: 768px) {
    .nav {
        padding: 0.75rem 1.25rem;
    }
    .nav-cluster { 
        position: absolute; 
        top: 100%; 
        right: 0; 
        background: rgba(255,255,255,0.98); 
        box-shadow: 0 10px 30px rgba(0,0,0,0.08); 
        border: 1px solid rgba(0,0,0,0.06); 
        padding: 1rem 1.25rem; 
        border-radius: 12px; 
        flex-direction: column; 
        align-items: flex-start; 
        gap: 1rem; 
        transform-origin: top right; 
        transform: scale(0.9) translateY(-10px); 
        opacity: 0; 
        pointer-events: none; 
        transition: opacity .3s ease, transform .3s ease; 
    }
    .nav-cluster.open { 
        opacity: 1; 
        pointer-events: auto; 
        transform: scale(1) translateY(0); 
    }
    .nav-links { 
        flex-direction: column; 
        gap: 0.75rem; 
    }
    .nav-divider { display: none; }
    .nav-toggle { display: inline-flex; }
    .main { margin-top: 100px; }
    .hero { min-height: 60vh; padding-top: 2rem; }
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
    .hero-title { font-size: clamp(1.8rem, 6vw, 2.6rem); }
    .hero-subtitle { font-size: clamp(0.9rem, 3vw, 1.1rem); margin-bottom: 1.5rem; }
    
    .btn {
        padding: 0.8rem 1.5rem;
        font-size: 0.8rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    section {
        padding: 3rem 0;
    }
}

@media (max-width: 480px) {
    .nav-links {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .main {
        margin-top: 160px;
    }
    
    .container {
        padding: 0 1rem;
    }
}

/* Burger toggle button */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: transparent;
    border: 2px solid rgba(0,0,0,0.1);
    padding: 6px 10px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.3s ease, border-color 0.3s ease;
}
.nav-toggle:hover { background: rgba(0,0,0,0.04); }
.nav-toggle:focus-visible { outline:2px solid var(--fb-focus); outline-offset:4px; }
.nav-toggle-bar { width:22px; height:2px; background: var(--fb-text); border-radius:2px; transition: transform .3s ease, opacity .3s ease; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Desktop ensure cluster visible */
@media (min-width: 769px) {
    .nav-cluster { gap: 1.75rem; }
    .nav-links { display: flex !important; }
}