:root{
  --bg: #0a0e14;
  --bg-alt: #0d1320;
  --panel: #111826;
  --panel-border: #1f2b3d;
  --text: #e8edf5;
  --text-dim: #8a96a8;
  --accent: #00e5c7;
  --accent-2: #5b8cff;
  --danger: #ff5c72;
  --radius: 14px;
  --maxw: 1180px;
  --font: 'Space Grotesk', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, monospace;
}

*{box-sizing:border-box; margin:0; padding:0;}
html{scroll-behavior:smooth;}
body{
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height:1.6;
  overflow-x:hidden;
}
.mono{font-family:var(--mono);}
a{color:inherit; text-decoration:none;}
ul{list-style:none;}
img{max-width:100%; display:block;}

/* background fx */
.bg-grid{
  position:fixed; inset:0; z-index:-2;
  background-image:
    linear-gradient(rgba(0,229,199,0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,229,199,0.045) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 40%, transparent 100%);
}
.bg-glow{
  position:fixed; z-index:-1; inset:0;
  background:
    radial-gradient(600px 400px at 15% 10%, rgba(91,140,255,0.16), transparent 60%),
    radial-gradient(500px 350px at 85% 30%, rgba(0,229,199,0.13), transparent 60%);
  pointer-events:none;
}

.section-inner{ max-width:var(--maxw); margin:0 auto; padding:0 32px; }

/* NAV */
.nav{
  position:sticky; top:0; z-index:100;
  background: rgba(10,14,20,0.75);
  backdrop-filter: blur(10px);
  border-bottom:1px solid var(--panel-border);
}
.nav-inner{
  max-width:var(--maxw); margin:0 auto; padding:16px 32px;
  display:flex; align-items:center; justify-content:space-between;
}
.logo{ font-weight:700; font-size:1.05rem; letter-spacing:-0.01em; }
.logo span{ color:var(--accent); }
.nav-links{ display:flex; gap:32px; }
.nav-links a{
  font-size:0.92rem; color:var(--text-dim); transition:color .2s;
  position:relative;
}
.nav-links a:hover{ color:var(--text); }
.nav-actions{ display:flex; align-items:center; gap:18px; }

.lang-toggle{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:999px;
  padding:6px 6px; display:flex; align-items:center; gap:6px; cursor:pointer;
  font-family:var(--mono); font-size:0.78rem;
}
.lang-opt{ padding:4px 9px; border-radius:999px; color:var(--text-dim); transition:.2s; }
.lang-opt.active{ background:var(--accent); color:#04120f; font-weight:600; }
.lang-sep{ color:var(--panel-border); }

.menu-toggle{ display:none; flex-direction:column; gap:5px; background:none; border:none; cursor:pointer; }
.menu-toggle span{ width:22px; height:2px; background:var(--text); display:block; }

/* HERO */
.hero{ padding:120px 32px 90px; position:relative; }
.hero-inner{ max-width:var(--maxw); margin:0 auto; }
.eyebrow{ color:var(--accent); font-size:0.82rem; letter-spacing:0.08em; margin-bottom:22px; }
h1{
  font-size: clamp(2.3rem, 5.4vw, 4.1rem);
  font-weight:700; letter-spacing:-0.02em; line-height:1.08;
  max-width: 16ch;
}
.accent{
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip:text; background-clip:text; color:transparent;
}
.hero-sub{
  margin-top:26px; font-size:1.12rem; color:var(--text-dim); max-width:58ch;
}
.hero-actions{ display:flex; gap:16px; margin-top:36px; flex-wrap:wrap; }

.btn{
  display:inline-flex; align-items:center; justify-content:center;
  padding:13px 26px; border-radius:10px; font-weight:600; font-size:0.95rem;
  transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
  border:1px solid transparent;
}
.btn-primary{
  background: var(--accent); color:#04120f;
  box-shadow: 0 0 0 0 rgba(0,229,199,0.4);
}
.btn-primary:hover{ transform:translateY(-2px); box-shadow:0 8px 24px rgba(0,229,199,0.22); }
.btn-ghost{ border-color:var(--panel-border); color:var(--text); }
.btn-ghost:hover{ border-color:var(--accent); color:var(--accent); transform:translateY(-2px); }

.hero-stats{
  display:flex; gap:56px; margin-top:72px; flex-wrap:wrap;
  border-top:1px solid var(--panel-border); padding-top:32px;
}
.stat{ display:flex; flex-direction:column; gap:6px; }
.stat-num{ font-size:2rem; font-weight:700; color:var(--text); }
.stat-label{ font-size:0.78rem; color:var(--text-dim); max-width:16ch; }

/* SECTIONS */
.section{ padding:100px 0; }
.section.alt{ background: var(--bg-alt); border-top:1px solid var(--panel-border); border-bottom:1px solid var(--panel-border); }
.tag{ color:var(--accent); font-size:0.8rem; letter-spacing:0.08em; margin-bottom:16px; }
.section h2{ font-size:clamp(1.8rem, 3.2vw, 2.6rem); font-weight:700; letter-spacing:-0.01em; max-width:20ch; }
.section-sub{ color:var(--text-dim); margin-top:14px; max-width:60ch; font-size:1.02rem; }

/* ABOUT */
.about-grid{ display:grid; grid-template-columns: 1.4fr 1fr; gap:64px; margin-top:36px; align-items:start; }
.about-grid p{ color:var(--text-dim); margin-top:16px; font-size:1.02rem; }
.about-skills h3{ font-size:0.95rem; color:var(--text-dim); font-weight:600; margin-bottom:16px; text-transform:uppercase; letter-spacing:0.04em; }
.about-skills h3.chips-title-2{ margin-top:28px; }
.chips{ display:flex; flex-wrap:wrap; gap:10px; }
.chips li{
  background:var(--panel); border:1px solid var(--panel-border); padding:8px 14px;
  border-radius:8px; font-family:var(--mono); font-size:0.82rem; color:var(--text);
}

/* EXPERTISE */
.expertise-grid{ display:grid; grid-template-columns:repeat(auto-fit, minmax(220px, 1fr)); gap:22px; margin-top:44px; }
.ecard{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:var(--radius);
  padding:28px 24px; transition: border-color .2s, transform .2s;
}
.ecard:hover{ border-color: var(--accent); transform:translateY(-4px); }
.ecard-num{ color:var(--accent); font-size:0.85rem; opacity:0.7; }
.ecard h3{ font-size:1.05rem; margin:14px 0 10px; font-weight:600; }
.ecard p{ color:var(--text-dim); font-size:0.92rem; }

/* PROJECTS */
.projects-grid{ display:grid; grid-template-columns:repeat(2,1fr); gap:24px; margin-top:44px; }
.pcard{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:var(--radius);
  padding:30px; display:flex; flex-direction:column; gap:14px; transition:border-color .2s, transform .2s;
}
.pcard:hover{ border-color:var(--accent-2); transform:translateY(-4px); }
.pcard-top{ display:flex; align-items:center; justify-content:space-between; }
.pcard-badge{
  font-family:var(--mono); font-size:0.72rem; letter-spacing:0.04em; color:var(--accent);
  border:1px solid rgba(0,229,199,0.35); padding:4px 10px; border-radius:999px;
}
.pcard h3{ font-size:1.2rem; font-weight:600; }
.pcard p{ color:var(--text-dim); font-size:0.94rem; }
.pcard-tags{ display:flex; flex-wrap:wrap; gap:8px; margin-top:auto; padding-top:8px; }
.pcard-tags span{
  font-family:var(--mono); font-size:0.72rem; color:var(--text-dim);
  background:rgba(255,255,255,0.03); border:1px solid var(--panel-border); padding:4px 9px; border-radius:6px;
}
.pcard.featured{ grid-column: span 2; }
.pcard.featured .pcard-body{ display:grid; grid-template-columns:1.3fr 1fr; gap:32px; }
.pcard-link{
  color:var(--accent); font-size:0.88rem; font-weight:600; margin-top:4px;
  display:inline-flex; align-items:center; gap:6px; transition:gap .15s;
}
.pcard-link:hover{ gap:10px; }

/* CONTACT */
.contact-section{ text-align:left; }
.contact-actions{ margin-top:30px; display:flex; gap:16px; flex-wrap:wrap; }

/* SUBPAGE HEADER (slm.html, contact.html) */
.page-header{ padding:130px 32px 70px; }
.page-header .section-inner{ max-width:var(--maxw); }
.page-header h1{ max-width:22ch; }
.back-link{
  display:inline-flex; align-items:center; gap:8px; color:var(--text-dim);
  font-family:var(--mono); font-size:0.85rem; margin-bottom:26px; transition:color .2s;
}
.back-link:hover{ color:var(--accent); }

/* ARCHITECTURE DIAGRAM / CONTENT BLOCKS */
.content-block{ margin-top:52px; }
.content-block h2{ font-size:1.5rem; font-weight:700; margin-bottom:14px; }
.content-block p{ color:var(--text-dim); font-size:1.02rem; max-width:70ch; }
.content-block p + p{ margin-top:12px; }
.diagram-wrap{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:var(--radius);
  padding:28px; margin-top:24px; overflow-x:auto;
}
.feature-list{ display:grid; grid-template-columns:repeat(2,1fr); gap:18px; margin-top:24px; }
.feature-item{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:12px; padding:22px;
}
.feature-item h4{ font-size:1rem; margin-bottom:8px; color:var(--text); }
.feature-item p{ font-size:0.9rem; color:var(--text-dim); }
.tags-row{ display:flex; flex-wrap:wrap; gap:10px; margin-top:24px; }
.tags-row span{
  font-family:var(--mono); font-size:0.78rem; color:var(--accent);
  border:1px solid rgba(0,229,199,0.3); padding:6px 12px; border-radius:999px;
}

/* CONTACT FORM */
.contact-layout{ display:grid; grid-template-columns:1.1fr 0.9fr; gap:56px; margin-top:44px; align-items:start; }
.form-group{ margin-bottom:20px; }
.form-group label{ display:block; font-size:0.85rem; color:var(--text-dim); margin-bottom:8px; font-family:var(--mono); }
.form-group input, .form-group textarea{
  width:100%; background:var(--panel); border:1px solid var(--panel-border); border-radius:10px;
  padding:13px 16px; color:var(--text); font-family:var(--font); font-size:0.96rem;
  transition:border-color .2s;
}
.form-group input:focus, .form-group textarea:focus{ outline:none; border-color:var(--accent); }
.form-group textarea{ resize:vertical; min-height:140px; }
.form-status{ margin-top:16px; font-size:0.9rem; font-family:var(--mono); min-height:1.2em; }
.form-status.success{ color:var(--accent); }
.form-status.error{ color:var(--danger); }
.contact-side{
  background:var(--panel); border:1px solid var(--panel-border); border-radius:var(--radius); padding:30px;
}
.contact-side h3{ font-size:1.05rem; margin-bottom:12px; }
.contact-side p{ color:var(--text-dim); font-size:0.94rem; margin-bottom:18px; }
.contact-side .btn{ width:100%; }

/* FOOTER */
.footer{ padding:36px 0; border-top:1px solid var(--panel-border); }
.footer-inner{ display:flex; justify-content:space-between; align-items:center; color:var(--text-dim); font-size:0.85rem; flex-wrap:wrap; gap:16px; }
.footer-social{ display:flex; align-items:center; gap:16px; }
.footer-social a{ color:var(--text-dim); display:inline-flex; transition:color .2s, transform .2s; }
.footer-social a:hover{ color:var(--accent); transform:translateY(-2px); }
.footer-social svg{ width:19px; height:19px; fill:currentColor; }

/* RESPONSIVE */
@media (max-width: 900px){
  .about-grid{ grid-template-columns:1fr; gap:32px; }
  .expertise-grid{ grid-template-columns:repeat(2,1fr); }
  .projects-grid{ grid-template-columns:1fr; }
  .pcard.featured{ grid-column:span 1; }
  .pcard.featured .pcard-body{ grid-template-columns:1fr; }
  .feature-list{ grid-template-columns:1fr; }
  .contact-layout{ grid-template-columns:1fr; gap:36px; }
}
@media (max-width: 720px){
  .nav-links{
    position:fixed; top:64px; left:0; right:0; background:var(--bg);
    flex-direction:column; padding:24px 32px; gap:20px;
    border-bottom:1px solid var(--panel-border);
    transform:translateY(-150%); transition:transform .25s ease; z-index:99;
  }
  .nav-links.open{ transform:translateY(0); }
  .menu-toggle{ display:flex; }
  .hero{ padding:80px 20px 60px; }
  .section{ padding:64px 0; }
  .section-inner{ padding:0 20px; }
  .expertise-grid{ grid-template-columns:1fr; }
  .hero-stats{ gap:32px; }
  .page-header{ padding:96px 20px 50px; }
}