/* assets/css/styles.css — Final theme for DuongCoder */
:root{
  --page-bg:#f7fbff;
  --surface:#ffffff;
  --muted:#667085;
  --primary:#0ea5ff;
  --primary-2:#7c3aed;
  --accent:#06b6d4;
  --accent-2:#fb923c;
  --border:#e6ecff;
  --radius:12px;
  --shadow:0 10px 30px rgba(15,23,42,0.06);
  --maxwidth:1200px;
  --pad:24px;
  --glass: rgba(255,255,255,0.7);
  --fg:#0f1724;
}

/* Reset */
*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Arial;
  background:linear-gradient(180deg,#eef6ff 0%, var(--page-bg) 100%);
  color:var(--fg);
  -webkit-font-smoothing:antialiased;
  padding:20px;
}

/* Container */
.container{
  max-width:var(--maxwidth);
  margin:0 auto;
  padding:var(--pad);
  display:flex;
  flex-direction:column;
  gap:20px;
}

/* Header */
.header{
  position:sticky; top:12px; z-index:50;
  display:flex; align-items:center; justify-content:space-between;
  gap:12px; padding:12px 18px; border-radius:12px;
  background:linear-gradient(90deg, rgba(255,255,255,0.95), rgba(250,250,255,0.75));
  border:1px solid var(--border); box-shadow:var(--shadow); backdrop-filter: blur(6px);
}
.brand{display:flex;gap:12px;align-items:center;text-decoration:none;color:inherit}
.logo{width:52px;height:52px;border-radius:10px;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:800;
  background:linear-gradient(135deg,var(--primary),var(--primary-2)); box-shadow:0 8px 28px rgba(124,58,237,0.12);}
.brand .title{font-weight:700;font-size:18px}
.brand .sub{font-size:12px;color:var(--muted)}

/* Nav */
.nav{display:flex;gap:10px;align-items:center}
.nav a{color:var(--primary);text-decoration:none;padding:8px 12px;border-radius:10px;font-weight:600}
.nav a:hover{background:rgba(14,165,255,0.06)}
.btn-primary{background:linear-gradient(90deg,var(--primary),var(--primary-2));color:#fff;padding:9px 14px;border-radius:10px;text-decoration:none;font-weight:700;box-shadow:0 8px 30px rgba(14,165,255,0.12)}
.btn-ghost{background:transparent;border:1px solid var(--border);padding:8px 12px;border-radius:10px;color:var(--muted)}

/* Layout */
.hero{display:flex;gap:20px;align-items:flex-start;flex-wrap:wrap}
.main{flex:1;display:flex;flex-direction:column;gap:16px}
.sidebar{width:320px;flex-shrink:0}

/* Card */
.card{background:var(--surface);border-radius:12px;padding:18px;border:1px solid var(--border);box-shadow:var(--shadow);transition:transform .18s ease,box-shadow .18s ease}
.card:hover{transform:translateY(-4px);box-shadow:0 22px 44px rgba(15,23,42,0.08)}

/* Titles */
.h1{font-size:22px;margin:0 0 8px 0;font-weight:700}
.h2{font-size:18px;margin:0 0 8px 0;color:#0b1220}
.lead{color:var(--muted);line-height:1.6}

/* Forms */
label{display:block;font-weight:600;margin-bottom:6px;color:#0b1220}
.input,textarea{width:100%;padding:11px;border-radius:10px;border:1px solid var(--border);background:#fff;outline:none;font-size:14px}
.input:focus,textarea:focus{box-shadow:0 12px 30px rgba(14,165,255,0.07);border-color:var(--primary)}
textarea{min-height:110px;resize:vertical}

/* Buttons */
.actions{display:flex;gap:10px;align-items:center;margin-top:8px}
.btn{padding:10px 14px;border-radius:10px;border:0;cursor:pointer}
.btn-primary{background:linear-gradient(90deg,var(--primary),var(--primary-2));color:#fff;font-weight:700;box-shadow:0 8px 30px rgba(14,165,255,0.12)}
.btn-primary:hover{transform:translateY(-2px)}
.btn-ghost{background:transparent;border:1px solid var(--border);color:var(--muted)}

/* Projects */
.project{border-radius:10px;padding:14px;margin-bottom:12px;background:linear-gradient(180deg,#fff,#fbfdff);border-left:6px solid var(--primary)}
.project h3{margin:0}
.project .meta{font-size:13px;color:var(--muted);margin-bottom:8px}
.project a{color:var(--primary);text-decoration:none;font-weight:600}

/* Footer */
.footer{display:flex;justify-content:space-between;align-items:center;padding:12px 16px;border-radius:12px;background:linear-gradient(90deg,#fff,#fbfdff);border:1px solid var(--border);color:var(--muted)}

/* Small responsive */
@media (max-width:980px){
  .hero{flex-direction:column}
  .sidebar{width:100%}
  .header{flex-direction:column;align-items:flex-start;gap:10px}
}