/* ============================================
   Safal Kunwar — Portfolio Website
   Design System & Styles
   ============================================ */

/* ---------- Google Font ---------- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Fira+Code:wght@400;500&display=swap');

/* ---------- CSS Custom Properties ---------- */
:root {
  /* Palette */
  --bg-primary:    #0a192f;
  --bg-secondary:  #112240;
  --bg-card:       #1a2d4d;
  --accent:        #64ffda;
  --accent-dim:    rgba(100, 255, 218, .12);
  --text-primary:  #ccd6f6;
  --text-secondary:#8892b0;
  --text-heading:  #e6f1ff;
  --white:         #ffffff;
  --danger:        #ff6b6b;

  /* Typography */
  --font-sans:  'Inter', system-ui, -apple-system, sans-serif;
  --font-mono:  'Fira Code', 'Courier New', monospace;

  /* Sizing */
  --nav-height:   72px;
  --max-width:    1200px;
  --section-pad:  100px 0;
  --radius-sm:    8px;
  --radius-md:    12px;
  --radius-lg:    20px;

  /* Transitions */
  --ease-smooth:  cubic-bezier(.4,0,.2,1);
}

/* ---------- Reset ---------- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
html{scroll-behavior:smooth;scroll-padding-top:var(--nav-height);}
body{
  font-family:var(--font-sans);
  background:var(--bg-primary);
  color:var(--text-secondary);
  line-height:1.7;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--accent);text-decoration:none;transition:color .3s var(--ease-smooth);}
a:hover{color:var(--white);}
img{max-width:100%;display:block;}
ul{list-style:none;}
button{cursor:pointer;font-family:inherit;}

/* ---------- Utility ---------- */
.container{width:90%;max-width:var(--max-width);margin:0 auto;}
.section-heading{
  display:flex;align-items:center;gap:14px;
  font-size:clamp(1.5rem,3vw,2rem);
  font-weight:700;
  color:var(--text-heading);
  margin-bottom:48px;
}
.section-heading .num{
  font-family:var(--font-mono);font-size:.9rem;color:var(--accent);font-weight:400;
}
.section-heading::after{
  content:'';flex:1;height:1px;
  background:linear-gradient(90deg,var(--bg-card),transparent);
}
.highlight{color:var(--accent);}

/* ---------- Preloader ---------- */
#preloader{
  position:fixed;inset:0;z-index:9999;
  background:var(--bg-primary);
  display:flex;align-items:center;justify-content:center;
  transition:opacity .6s var(--ease-smooth), visibility .6s;
}
#preloader.hidden{opacity:0;visibility:hidden;}
.loader{
  width:48px;height:48px;
  border:3px solid var(--bg-card);
  border-top-color:var(--accent);
  border-radius:50%;
  animation:spin .8s linear infinite;
}
@keyframes spin{to{transform:rotate(360deg)}}

/* ---------- Navbar ---------- */
.navbar{
  position:fixed;top:0;left:0;width:100%;
  height:var(--nav-height);z-index:1000;
  background:rgba(10,25,47,.85);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid rgba(100,255,218,.06);
  transition:transform .35s var(--ease-smooth), box-shadow .35s;
}
.navbar.hidden-nav{transform:translateY(-100%);}
.navbar.scrolled{box-shadow:0 10px 30px rgba(0,0,0,.3);}
.nav-inner{
  display:flex;align-items:center;justify-content:space-between;
  height:100%;
}
.logo{
  font-size:1.4rem;font-weight:800;color:var(--accent);
  letter-spacing:-0.5px;position:relative;
}
.logo span{color:var(--text-heading);}
.nav-links{display:flex;align-items:center;gap:32px;}
.nav-links a{
  font-size:.85rem;font-weight:500;letter-spacing:.5px;
  color:var(--text-secondary);position:relative;
  transition:color .3s;
}
.nav-links a .link-num{
  font-family:var(--font-mono);font-size:.75rem;color:var(--accent);margin-right:4px;
}
.nav-links a:hover,.nav-links a.active{color:var(--accent);}
.nav-links a::after{
  content:'';position:absolute;bottom:-4px;left:0;width:0;height:2px;
  background:var(--accent);transition:width .3s var(--ease-smooth);
}
.nav-links a:hover::after,.nav-links a.active::after{width:100%;}

/* Resume button in nav */
.btn-resume{
  padding:8px 18px;
  border:1.5px solid var(--accent);
  border-radius:var(--radius-sm);
  font-size:.82rem;font-weight:500;
  color:var(--accent);background:transparent;
  transition:background .3s, color .3s;
}
.btn-resume:hover{background:var(--accent-dim);}

/* Hamburger */
.hamburger{
  display:none;flex-direction:column;gap:5px;
  background:none;border:none;cursor:pointer;
  padding:4px;z-index:1001;
}
.hamburger span{
  width:28px;height:2px;background:var(--accent);
  transition:transform .3s,opacity .3s;
}
.hamburger.active span:nth-child(1){transform:translateY(7px) rotate(45deg);}
.hamburger.active span:nth-child(2){opacity:0;}
.hamburger.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}

/* ---------- Hero Section ---------- */
.hero{
  min-height:100vh;
  display:flex;align-items:center;
  position:relative;overflow:hidden;
  padding:calc(var(--nav-height) + 40px) 0 60px;
}
.hero-bg{
  position:absolute;inset:0;z-index:0;
  background:url('../assets/images/hero-bg.png') center/cover no-repeat;
  opacity:.18;
}
.hero-particles{position:absolute;inset:0;z-index:1;}

.hero-content{position:relative;z-index:2;max-width:700px;}
.hero-greeting{
  font-family:var(--font-mono);font-size:clamp(.9rem,1.5vw,1.05rem);
  color:var(--accent);margin-bottom:20px;
  display:flex;align-items:center;gap:8px;
}
.wave{display:inline-block;animation:wave 2.5s infinite;transform-origin:70% 70%;}
@keyframes wave{
  0%,100%{transform:rotate(0)}
  10%{transform:rotate(14deg)}
  20%{transform:rotate(-8deg)}
  30%{transform:rotate(14deg)}
  40%{transform:rotate(-4deg)}
  50%{transform:rotate(10deg)}
  60%,100%{transform:rotate(0)}
}
.hero-name{
  font-size:clamp(2.4rem,6vw,4.2rem);
  font-weight:900;color:var(--text-heading);
  line-height:1.1;margin-bottom:8px;
  letter-spacing:-1.5px;
}
.hero-tagline{
  font-size:clamp(1.4rem,3.5vw,2.8rem);
  font-weight:700;
  background:linear-gradient(135deg,var(--text-secondary),var(--accent));
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;
  background-clip:text;
  line-height:1.2;margin-bottom:24px;
}
.hero-description{
  max-width:540px;font-size:1.05rem;
  margin-bottom:36px;line-height:1.8;
}
.hero-cta{display:flex;gap:16px;flex-wrap:wrap;}
.btn-primary{
  padding:14px 32px;
  background:transparent;
  border:1.5px solid var(--accent);
  border-radius:var(--radius-sm);
  color:var(--accent);
  font-size:.92rem;font-weight:600;
  transition:background .3s, transform .15s;
}
.btn-primary:hover{background:var(--accent-dim);transform:translateY(-2px);}
.btn-primary.filled{
  background:var(--accent);color:var(--bg-primary);
}
.btn-primary.filled:hover{
  background:#4de8c4;transform:translateY(-2px);color:var(--bg-primary);
}

/* Social sidebar */
.social-sidebar{
  position:fixed;bottom:0;left:40px;z-index:100;
  display:flex;flex-direction:column;align-items:center;gap:20px;
}
.social-sidebar a{
  color:var(--text-secondary);font-size:1.2rem;
  transition:color .3s,transform .3s;
}
.social-sidebar a:hover{color:var(--accent);transform:translateY(-3px);}
.social-sidebar::after{
  content:'';width:1px;height:90px;background:var(--text-secondary);
}

/* Email sidebar */
.email-sidebar{
  position:fixed;bottom:0;right:40px;z-index:100;
  display:flex;flex-direction:column;align-items:center;gap:20px;
}
.email-sidebar a{
  writing-mode:vertical-rl;
  font-family:var(--font-mono);font-size:.78rem;letter-spacing:2px;
  color:var(--text-secondary);transition:color .3s,transform .3s;
}
.email-sidebar a:hover{color:var(--accent);transform:translateY(-3px);}
.email-sidebar::after{
  content:'';width:1px;height:90px;background:var(--text-secondary);
}

/* ---------- About Section ---------- */
.about{padding:var(--section-pad);}
.about-grid{display:grid;grid-template-columns:3fr 2fr;gap:48px;align-items:start;}
.about-text p{margin-bottom:18px;font-size:1rem;}
.about-text .tech-stack{margin-top:24px;}
.about-text .tech-stack h4{
  font-size:.9rem;color:var(--text-heading);margin-bottom:14px;
}
.tech-list{
  display:grid;grid-template-columns:repeat(2,1fr);gap:8px 24px;
}
.tech-list li{
  font-family:var(--font-mono);font-size:.82rem;
  display:flex;align-items:center;gap:8px;
  color:var(--text-secondary);
}
.tech-list li::before{content:'▹';color:var(--accent);font-size:.7rem;}

.about-image-wrapper{
  position:relative;max-width:320px;justify-self:center;
}
.about-image{
  border-radius:var(--radius-md);
  filter:grayscale(30%) contrast(1.05);
  transition:filter .4s;
  position:relative;z-index:2;
}
.about-image:hover{filter:none;}
.about-image-wrapper::after{
  content:'';position:absolute;
  top:16px;left:16px;width:100%;height:100%;
  border:2px solid var(--accent);border-radius:var(--radius-md);
  z-index:1;transition:all .3s;
}
.about-image-wrapper:hover::after{top:10px;left:10px;}

/* ---------- Skills Section ---------- */
.skills{padding:var(--section-pad);background:var(--bg-secondary);}
.skills-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:24px;}
.skill-card{
  background:var(--bg-card);
  border:1px solid rgba(100,255,218,.06);
  border-radius:var(--radius-md);
  padding:28px 20px;text-align:center;
  transition:transform .35s var(--ease-smooth),border-color .35s,box-shadow .35s;
}
.skill-card:hover{
  transform:translateY(-6px);
  border-color:var(--accent);
  box-shadow:0 12px 40px rgba(100,255,218,.08);
}
.skill-icon{
  font-size:2.4rem;margin-bottom:14px;
  display:inline-block;
  transition:transform .3s;
}
.skill-card:hover .skill-icon{transform:scale(1.15);}
.skill-card h3{
  font-size:.88rem;font-weight:600;color:var(--text-heading);margin-bottom:4px;
}
.skill-card p{font-size:.75rem;color:var(--text-secondary);}

/* ---------- Projects Section ---------- */
.projects{padding:var(--section-pad);}
.projects-grid{display:flex;flex-direction:column;gap:64px;}

.project-card{
  display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;
  background:var(--bg-secondary);
  border-radius:var(--radius-lg);
  overflow:hidden;
  border:1px solid rgba(100,255,218,.04);
  transition:border-color .35s,box-shadow .4s;
}
.project-card:hover{
  border-color:rgba(100,255,218,.12);
  box-shadow:0 20px 60px rgba(0,0,0,.25);
}
.project-card:nth-child(even){direction:rtl;}
.project-card:nth-child(even) > *{direction:ltr;}

.project-image{
  position:relative;overflow:hidden;
  height:100%;min-height:320px;
}
.project-image img{
  width:100%;height:100%;object-fit:cover;
  transition:transform .6s var(--ease-smooth);
}
.project-card:hover .project-image img{transform:scale(1.05);}
.project-image-overlay{
  position:absolute;inset:0;
  background:linear-gradient(135deg,rgba(10,25,47,.7),rgba(100,255,218,.08));
  transition:opacity .4s;
}
.project-card:hover .project-image-overlay{opacity:.4;}

.project-info{padding:40px;}
.project-label{
  font-family:var(--font-mono);font-size:.8rem;color:var(--accent);
  margin-bottom:8px;display:block;
}
.project-title{
  font-size:1.6rem;font-weight:700;color:var(--text-heading);
  margin-bottom:16px;
}
.project-desc{
  font-size:.95rem;line-height:1.7;margin-bottom:20px;
  color:var(--text-secondary);
}
.project-tech{
  display:flex;flex-wrap:wrap;gap:10px;margin-bottom:24px;
}
.project-tech span{
  font-family:var(--font-mono);font-size:.72rem;
  background:var(--accent-dim);color:var(--accent);
  padding:4px 12px;border-radius:20px;
}
.project-links{display:flex;gap:16px;}
.project-links a{
  font-size:1.15rem;color:var(--text-secondary);
  transition:color .3s,transform .3s;
}
.project-links a:hover{color:var(--accent);transform:translateY(-2px);}

/* ---------- Experience Timeline ---------- */
.experience{padding:var(--section-pad);background:var(--bg-secondary);}
.timeline{
  position:relative;max-width:700px;margin:0 auto;
  padding-left:32px;
}
.timeline::before{
  content:'';position:absolute;left:0;top:0;bottom:0;
  width:2px;
  background:linear-gradient(180deg,var(--accent),var(--bg-card));
}
.timeline-item{
  position:relative;padding:0 0 48px 32px;
}
.timeline-item:last-child{padding-bottom:0;}
.timeline-dot{
  position:absolute;left:-37px;top:6px;
  width:12px;height:12px;background:var(--accent);
  border-radius:50%;border:3px solid var(--bg-secondary);
  box-shadow:0 0 0 3px var(--accent-dim);
}
.timeline-date{
  font-family:var(--font-mono);font-size:.78rem;color:var(--accent);
  margin-bottom:6px;
}
.timeline-title{
  font-size:1.15rem;font-weight:600;color:var(--text-heading);
  margin-bottom:4px;
}
.timeline-company{
  font-size:.92rem;color:var(--accent);margin-bottom:10px;
}
.timeline-desc{font-size:.92rem;line-height:1.7;}
.timeline-desc li{
  margin-bottom:6px;padding-left:18px;position:relative;
}
.timeline-desc li::before{
  content:'▹';color:var(--accent);position:absolute;left:0;
}

/* ---------- Contact Section ---------- */
.contact{padding:var(--section-pad);text-align:center;}
.contact-inner{max-width:600px;margin:0 auto;}
.contact .section-heading{justify-content:center;}
.contact-subtitle{
  font-size:clamp(1.6rem,3vw,2.4rem);
  font-weight:700;color:var(--text-heading);
  margin-bottom:16px;
}
.contact-text{
  font-size:1.05rem;margin-bottom:40px;
  max-width:480px;margin-left:auto;margin-right:auto;
}

/* Contact form */
.contact-form{
  display:flex;flex-direction:column;gap:20px;
  text-align:left;margin-bottom:32px;
}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:20px;}
.form-group{display:flex;flex-direction:column;gap:6px;}
.form-group label{
  font-family:var(--font-mono);font-size:.78rem;
  color:var(--accent);
}
.form-group input, .form-group textarea{
  background:var(--bg-secondary);
  border:1px solid rgba(100,255,218,.1);
  border-radius:var(--radius-sm);
  padding:12px 16px;
  color:var(--text-primary);
  font-family:var(--font-sans);font-size:.92rem;
  transition:border-color .3s,box-shadow .3s;
  resize:vertical;
}
.form-group input:focus, .form-group textarea:focus{
  outline:none;
  border-color:var(--accent);
  box-shadow:0 0 0 3px var(--accent-dim);
}
.form-group textarea{min-height:140px;}
.form-submit{
  padding:14px 40px;
  background:transparent;
  border:1.5px solid var(--accent);
  border-radius:var(--radius-sm);
  color:var(--accent);
  font-size:.92rem;font-weight:600;
  font-family:var(--font-mono);
  cursor:pointer;
  transition:background .3s, transform .15s;
  align-self:center;
}
.form-submit:hover{
  background:var(--accent-dim);
  transform:translateY(-2px);
}

.contact-or{
  font-family:var(--font-mono);font-size:.82rem;
  color:var(--text-secondary);margin-bottom:16px;
}

/* ---------- Footer ---------- */
.footer{
  padding:24px 0;text-align:center;
  font-family:var(--font-mono);font-size:.78rem;
  color:var(--text-secondary);
  border-top:1px solid rgba(100,255,218,.06);
}
.footer a{color:var(--accent);}
.footer-socials{
  display:none;
  justify-content:center;gap:20px;margin-bottom:12px;
}
.footer-socials a{color:var(--text-secondary);font-size:1.1rem;}
.footer-socials a:hover{color:var(--accent);}

/* ---------- Scroll-reveal animation ---------- */
.reveal{
  opacity:0;transform:translateY(30px);
  transition:opacity .7s var(--ease-smooth), transform .7s var(--ease-smooth);
}
.reveal.active{opacity:1;transform:translateY(0);}

/* ---------- Custom scrollbar ---------- */
::-webkit-scrollbar{width:8px;}
::-webkit-scrollbar-track{background:var(--bg-primary);}
::-webkit-scrollbar-thumb{
  background:var(--bg-card);border-radius:4px;
}
::-webkit-scrollbar-thumb:hover{background:var(--accent);}

/* ---------- Back to top ---------- */
.back-to-top{
  position:fixed;bottom:32px;right:32px;z-index:100;
  width:44px;height:44px;
  background:var(--accent-dim);
  border:1.5px solid var(--accent);
  border-radius:50%;
  color:var(--accent);font-size:1.1rem;
  display:flex;align-items:center;justify-content:center;
  opacity:0;visibility:hidden;transform:translateY(20px);
  transition:all .35s var(--ease-smooth);
  cursor:pointer;
}
.back-to-top.visible{opacity:1;visibility:visible;transform:translateY(0);}
.back-to-top:hover{background:var(--accent);color:var(--bg-primary);}

/* ===========================================
   Responsive
   =========================================== */
@media(max-width:1024px){
  .about-grid{grid-template-columns:1fr;gap:40px;}
  .about-image-wrapper{max-width:260px;justify-self:center;}
  .project-card{grid-template-columns:1fr;}
  .project-card:nth-child(even){direction:ltr;}
  .project-image{min-height:240px;}
}

@media(max-width:768px){
  .nav-links{
    position:fixed;top:0;right:-100%;width:70%;max-width:320px;height:100vh;
    background:var(--bg-secondary);
    flex-direction:column;justify-content:center;gap:28px;
    padding:40px;
    transition:right .4s var(--ease-smooth);
    box-shadow:-10px 0 40px rgba(0,0,0,.3);
  }
  .nav-links.open{right:0;}
  .hamburger{display:flex;}
  .social-sidebar,.email-sidebar{display:none;}
  .footer-socials{display:flex;}
  .hero-name{font-size:clamp(2rem,8vw,3rem);}
  .hero-tagline{font-size:clamp(1.2rem,5vw,2rem);}
  .form-row{grid-template-columns:1fr;}
  .skills-grid{grid-template-columns:repeat(auto-fit,minmax(130px,1fr));}
}

@media(max-width:480px){
  .hero{padding:calc(var(--nav-height) + 20px) 0 40px;}
  .hero-content{width:100%;}
  .hero-cta{flex-direction:column;}
  .btn-primary{width:100%;text-align:center;}
  .project-info{padding:24px;}
  .project-title{font-size:1.3rem;}
}