:root{
  --bg-1: #0b0f14;
  --bg-2: #0d1117;
  --primary: var(--user-3);
  --accent: #7A5CFF;
  /* RGB helpers for glow/rgba uses */
  --primary-rgb: 255,137,76; /* from #ff894c */
  --accent-rgb: 122,92,255; /* from #7A5CFF */
  /* User-provided palette (from css_style.text) */
  --user-1: #363636; /* .first-color */
  --user-2: #dc2f2f; /* .second-color */
  --user-3: #ff894c; /* .third-color */
  --user-4: #f8f8f8; /* .fourth-color */
  --muted: #9aa6b2;
  --glass: rgba(255,255,255,0.04);
  --gap: 1rem;
  --radius: 12px;
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Noto Sans TC', 'Helvetica Neue', Arial, 'PingFang TC', 'Microsoft JhengHei', sans-serif;
  background: radial-gradient(1200px 600px at 10% 10%, rgba(var(--accent-rgb),0.06), transparent), linear-gradient(180deg,var(--bg-1),var(--bg-2));
  color:#e6eef6;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  scroll-behavior:smooth;
}

.container{max-width:1100px;margin:0 auto;padding:1rem}

.skip-link{position:absolute;left:-9999px;top:auto;width:1px;height:1px;overflow:hidden}
.skip-link:focus{left:1rem;top:1rem;width:auto;height:auto;background:var(--glass);padding:.5rem;border-radius:6px}

/* Header */
.site-header{position:fixed;top:0;left:0;right:0;z-index:50;backdrop-filter: blur(0px);transition:all .25s ease}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:.75rem 1rem}
.brand{font-weight:700;color:var(--primary);font-size:1.1rem}

.nav-toggle{display:none}
.nav-toggle-label{display:none}

.site-nav ul{list-style:none;margin:0;padding:0;display:flex;gap:1rem}
.site-nav a{color:var(--muted);text-decoration:none;padding:.5rem;border-radius:8px}
.site-nav a:focus{outline:2px solid var(--primary);outline-offset:2px}

.site-header.scrolled{background:linear-gradient(180deg, rgba(13,17,23,0.6), rgba(13,17,23,0.4));box-shadow:0 6px 18px rgba(0,0,0,0.6);backdrop-filter: blur(6px)}

/* Hero */
.hero{min-height:72vh;display:flex;align-items:center;justify-content:center;position:relative;padding-top:4rem}
.hero-bg{position:absolute;inset:0;background-image:radial-gradient(circle at 20% 30%, rgba(var(--primary-rgb),0.06), transparent), repeating-linear-gradient(45deg, rgba(var(--accent-rgb),0.02) 0 2px, transparent 2px 6px);pointer-events:none}
.hero-inner{text-align:center;max-width:900px;padding:3rem 1rem}
.hero h1{font-size:2.25rem;margin:.2rem 0;color:transparent;background:linear-gradient(90deg,var(--primary) 70%,var(--accent) 100%);-webkit-background-clip:text;background-clip:text;text-shadow:0 0 12px rgba(var(--primary-rgb),0.32),0 0 32px rgba(var(--primary-rgb),0.18)}
.hero h2{font-size:1.1rem;margin:0;color:var(--muted);margin-bottom:.75rem}
.lead{color:#cfeef6;max-width:70ch;margin:0 auto 1rem}

.hero-ctas{display:flex;gap:.75rem;justify-content:center;margin-top:1rem}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:.65rem 1rem;border-radius:999px;text-decoration:none;border:1px solid transparent;cursor:pointer}
.btn:focus{outline:3px solid rgba(var(--primary-rgb),0.18);outline-offset:3px}

.btn-primary{
  background:linear-gradient(90deg,rgba(var(--primary-rgb),0.98) 60%,rgba(var(--accent-rgb),0.85) 100%);
  color:#181818;
  font-weight:700;
  box-shadow:0 0 0 2px rgba(var(--primary-rgb),0.25),0 0 16px 2px rgba(var(--primary-rgb),0.32),0 6px 30px 0 rgba(var(--primary-rgb),0.18);
  filter:drop-shadow(0 0 8px rgba(var(--primary-rgb),0.32));
  transform:translateZ(0);
  transition:transform .18s cubic-bezier(.4,1.6,.6,1),box-shadow .18s,filter .18s;
}
.btn-primary:hover{
  transform:scale(1.045);
  box-shadow:0 0 0 3px rgba(var(--primary-rgb),0.32),0 0 32px 6px rgba(var(--primary-rgb),0.38),0 10px 40px 0 rgba(var(--primary-rgb),0.22);
  filter:drop-shadow(0 0 16px rgba(var(--primary-rgb),0.38));
}

.btn-secondary{background:transparent;color:var(--primary);border:1px solid rgba(var(--primary-rgb),0.12)}
.btn-muted{background:transparent;color:var(--muted);border:1px dashed rgba(255,255,255,0.04);padding:.5rem .75rem}

/* Sections */
.section{padding:2.5rem 0}
.section h3{font-size:1.2rem;margin:0 0 1rem;color:var(--primary)}

.chips{display:flex;flex-wrap:wrap;gap:.5rem}
.chip{background:transparent;border:1px solid rgba(var(--accent-rgb),0.18);color:var(--muted);padding:.35rem .6rem;border-radius:999px}

/* Skills */
.skill-grid{display:grid;grid-template-columns:1fr;gap:1rem}
.skill-card{
  background:linear-gradient(180deg, rgba(var(--primary-rgb),0.06) 0 30%, rgba(255,255,255,0.01) 100%);
  padding:1rem;
  border-radius:12px;
  border:1.5px solid rgba(var(--primary-rgb),0.13);
  box-shadow:0 0 0 2px rgba(var(--primary-rgb),0.08),0 6px 18px rgba(0,0,0,0.6);
  animation:fadeUp .5s ease both;
}
.badge{display:inline-block;padding:.35rem .6rem;border-radius:8px;border:1px solid rgba(var(--primary-rgb),0.18);color:var(--primary);margin-right:.4rem}
.skill-desc{color:var(--muted);margin:.5rem 0}
.skill-level{font-weight:600;color:var(--accent)}

/* Timeline */
.timeline-wrap{display:flex;flex-direction:column;gap:1rem}
.timeline-item{display:flex;gap:1rem;align-items:flex-start}
.timeline-dot{width:12px;height:12px;background:var(--primary);border-radius:50%;margin-top:.6rem;box-shadow:0 0 12px rgba(var(--primary-rgb),0.18)}
.timeline-card{background:linear-gradient(180deg, rgba(255,255,255,0.01), transparent);padding:1rem;border-radius:8px;border:1px solid rgba(255,255,255,0.02)}
.muted{color:var(--muted)}

/* Projects */
.projects-grid{display:grid;grid-template-columns:1fr;gap:1rem}
.project-card{
  background:linear-gradient(180deg, rgba(var(--primary-rgb),0.07) 0 20%, rgba(255,255,255,0.02) 100%);
  padding:1rem;
  border-radius:12px;
  border:1.5px solid rgba(var(--primary-rgb),0.13);
  box-shadow:0 0 0 2px rgba(var(--primary-rgb),0.08),0 2px 12px rgba(var(--primary-rgb),0.10);
  display:flex;flex-direction:column;gap:.5rem;
}
.project-card img{width:100%;height:140px;object-fit:cover;border-radius:8px}
.project-chips{display:flex;gap:.4rem;flex-wrap:wrap}

/* Contact */
.contact-grid{display:grid;grid-template-columns:1fr;gap:.75rem}
.contact-card{display:block;padding:1rem;border-radius:8px;background:var(--glass);color:var(--primary);text-decoration:none}
.contact-cta{margin-top:1rem}

/* Footer & Back to top */
.site-footer{padding:1rem 0;text-align:center;color:var(--muted);border-top:1px solid rgba(255,255,255,0.02)}
.back-to-top{position:fixed;right:1rem;bottom:1rem;width:44px;height:44px;border-radius:50%;background:linear-gradient(180deg,var(--accent),var(--primary));color:#071018;border:none;cursor:pointer;box-shadow:0 8px 24px rgba(var(--primary-rgb),0.12)}

/* Responsive */
@media (min-width:601px){
  .skill-grid{grid-template-columns:repeat(2,1fr)}
  .projects-grid{grid-template-columns:repeat(2,1fr)}
  .contact-grid{grid-template-columns:repeat(3,1fr)}
}

@media (min-width:1024px){
  .skill-grid{grid-template-columns:repeat(3,1fr)}
  .projects-grid{grid-template-columns:repeat(3,1fr)}
  .timeline-wrap{gap:1.25rem}
  .hero h1{font-size:3rem}
}

/* Mobile nav */
@media (max-width:600px){
  .nav-toggle{display:block}
  .nav-toggle-label{display:block;cursor:pointer}
  .nav-toggle-label span{width:28px;height:2px;background:var(--primary);display:block;position:relative}
  .site-nav{position:absolute;right:1rem;top:64px;background:var(--glass);padding:.75rem;border-radius:8px;display:none}
  .nav-toggle:checked + .nav-toggle-label + .site-nav{display:block}
  .site-nav ul{flex-direction:column}
}

/* Animations */
@keyframes fadeUp{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* Focus visible support */
:focus{outline:none}
:focus-visible{outline:3px solid rgba(var(--primary-rgb),0.18);outline-offset:3px}

/* Utility classes for user palette (keeps original neon theme intact) */
.first-color{background:var(--user-1);color:var(--user-4)}
.second-color{background:var(--user-2);color:var(--user-4)}
.third-color{background:var(--user-3);color:var(--user-4)}
.fourth-color{background:var(--user-4);color:#0b0f14}

/* If you'd like to replace the site's primary neon color with your first color,
   set --primary: var(--user-1); in the :root. */