/* ==========================================================================
   Khaing Min Tun — Senior Backend Engineer Portfolio
   Light theme · "Engineering blueprint" design language
   ========================================================================== */
:root{
  --bg:            #F7F8FB;
  --bg-tint:       #F1F4FA;
  --surface:       #FFFFFF;
  --surface-2:     #EEF1F7;
  --border:        #E3E7F0;
  --border-strong: #D3D9E6;

  --ink:           #10142B;
  --ink-muted:     #4C5468;
  --ink-faint:     #8891A6;

  --accent:        #2A4CE0;   /* royal blue — primary brand */
  --accent-dark:   #17318F;
  --accent-tint:   #EAEEFD;
  --amber:         #F0982A;   /* warm accent — CTA / highlight */
  --amber-tint:    #FDF1E1;
  --teal:          #0E8E88;   /* secondary accent — data / tags */
  --teal-tint:     #E4F5F4;
  --success:       #1C9A5B;

  --font-display: 'Space Grotesk', sans-serif;
  --font-body:    'Inter', sans-serif;
  --font-mono:    'JetBrains Mono', monospace;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --maxw: 1180px;
  --pad: clamp(20px, 5vw, 64px);

  --shadow-sm: 0 1px 2px rgba(16,20,43,0.05), 0 1px 1px rgba(16,20,43,0.04);
  --shadow-md: 0 10px 30px -12px rgba(16,20,43,0.16);
  --shadow-lg: 0 24px 60px -20px rgba(16,20,43,0.22);
}

*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto; }
  *,*::before,*::after{ animation-duration:0.01ms !important; animation-iteration-count:1 !important; transition-duration:0.01ms !important; scroll-behavior:auto !important; }
}

body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}

img,svg{ max-width:100%; display:block; }
a{ color:inherit; text-decoration:none; }
ul{ margin:0; padding:0; list-style:none; }
h1,h2,h3,h4{ font-family:var(--font-display); margin:0; font-weight:600; letter-spacing:-0.01em; }
p{ margin:0; }

:focus-visible{
  outline:2px solid var(--accent);
  outline-offset:3px;
  border-radius:4px;
}

.wrap{
  max-width:var(--maxw);
  margin:0 auto;
  padding-inline:var(--pad);
}

.mono{ font-family:var(--font-mono); }

.eyebrow{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:0.14em;
  text-transform:uppercase;
  color:var(--accent-dark);
  display:inline-flex;
  align-items:center;
  gap:8px;
  background:var(--accent-tint);
  padding:6px 12px 6px 10px;
  border-radius:20px;
}
.eyebrow::before{
  content:"";
  width:7px; height:7px;
  border-radius:50%;
  background:var(--accent);
}

.section{
  padding-block: clamp(56px, 8vw, 108px);
}
.section-alt{ background:var(--bg-tint); }
.section-head{
  max-width:660px;
  margin-bottom: clamp(32px, 5vw, 56px);
}
.section-head h2{
  font-size:clamp(26px, 3.4vw, 38px);
  margin-top:14px;
  color:var(--ink);
}
.section-head p{
  margin-top:14px;
  color:var(--ink-muted);
  font-size:16px;
}

/* ---------- Buttons ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:13px 22px;
  border-radius:var(--radius-sm);
  font-family:var(--font-mono);
  font-size:14px;
  font-weight:500;
  border:1px solid transparent;
  cursor:pointer;
  transition:transform .15s ease, background .2s ease, border-color .2s ease, color .2s ease, box-shadow .2s ease;
  white-space:nowrap;
}
.btn:hover{ transform:translateY(-1px); }
.btn-primary{
  background:var(--accent);
  color:#fff;
  box-shadow:0 10px 24px -10px rgba(42,76,224,0.55);
}
.btn-primary:hover{ background:var(--accent-dark); }
.btn-outline{
  background:var(--surface);
  color:var(--ink);
  border-color:var(--border-strong);
}
.btn-outline:hover{ border-color:var(--accent); color:var(--accent-dark); }
.btn-ghost{
  background:transparent;
  color:var(--ink-muted);
  padding:13px 6px;
}
.btn-ghost:hover{ color:var(--accent); }

/* ---------- Nav ---------- */
.nav{
  position:sticky;
  top:0;
  z-index:50;
  background:rgba(247,248,251,0.86);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border);
}
.nav .wrap{
  display:flex;
  align-items:center;
  justify-content:space-between;
  height:72px;
}
.nav-brand{
  display:flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-weight:600;
  font-size:15px;
  color:var(--ink);
}
.nav-brand .dot{
  width:9px; height:9px; border-radius:50%;
  background:var(--success);
  box-shadow:0 0 0 3px rgba(28,154,91,0.16);
  animation:pulse 2.4s ease-in-out infinite;
}
@keyframes pulse{
  0%,100%{ opacity:1; }
  50%{ opacity:0.4; }
}
.nav-links{
  display:flex;
  align-items:center;
  gap:28px;
  font-size:14.5px;
  color:var(--ink-muted);
}
.nav-links a:hover{ color:var(--ink); }
.nav-cta{ display:flex; align-items:center; gap:14px; }
.nav-toggle{
  display:none;
  background:var(--surface);
  border:1px solid var(--border-strong);
  border-radius:8px;
  padding:8px 10px;
  color:var(--ink);
}

/* ---------- Hero ---------- */
.hero{
  position:relative;
  padding-block: clamp(56px, 9vw, 96px) clamp(48px, 7vw, 80px);
  overflow:hidden;
}
.hero::before{
  content:"";
  position:absolute;
  inset:0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size:44px 44px;
  -webkit-mask-image:radial-gradient(ellipse 80% 60% at 70% 20%, black 10%, transparent 70%);
  mask-image:radial-gradient(ellipse 80% 60% at 70% 20%, black 10%, transparent 70%);
  opacity:0.7;
  pointer-events:none;
}
.hero-grid{
  position:relative;
  display:grid;
  grid-template-columns: 1.15fr 0.9fr;
  gap:clamp(32px, 5vw, 64px);
  align-items:center;
}
.hero-copy h1{
  font-size:clamp(34px, 5.4vw, 56px);
  line-height:1.08;
  margin-top:18px;
  color:var(--ink);
}
.hero-copy h1 em{
  font-style:normal;
  color:var(--accent);
  position:relative;
}
.hero-copy .lede{
  margin-top:20px;
  font-size:clamp(16px, 1.6vw, 18.5px);
  color:var(--ink-muted);
  max-width:54ch;
}
.hero-ctas{
  margin-top:32px;
  display:flex;
  align-items:center;
  gap:16px;
  flex-wrap:wrap;
}
.hero-flags{
  margin-top:26px;
  display:flex;
  gap:22px;
  flex-wrap:wrap;
  font-size:13.5px;
  color:var(--ink-faint);
}
.hero-flags li{ display:flex; align-items:center; gap:8px; }
.hero-flags .dot{ width:6px; height:6px; border-radius:50%; background:var(--amber); }

/* Status panel */
.status-panel{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-lg);
  overflow:hidden;
  box-shadow:var(--shadow-lg);
}
.status-panel-head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding:14px 18px;
  border-bottom:1px solid var(--border);
  background:var(--surface-2);
  font-family:var(--font-mono);
  font-size:12px;
  color:var(--ink-faint);
}
.status-panel-head .dots{ display:flex; gap:6px; }
.status-panel-head .dots span{ width:9px; height:9px; border-radius:50%; background:var(--border-strong); }
.status-panel-body{ padding:22px 20px; }
.status-row{
  display:flex;
  justify-content:space-between;
  align-items:baseline;
  padding:11px 0;
  border-bottom:1px dashed var(--border);
  font-family:var(--font-mono);
  font-size:13.5px;
}
.status-row:last-child{ border-bottom:none; }
.status-row .k{ color:var(--ink-faint); }
.status-row .v{ color:var(--ink); font-weight:600; }
.status-row .v.accent{ color:var(--accent-dark); }
.status-stack{
  padding-top:16px;
  display:flex;
  flex-wrap:wrap;
  gap:8px;
}
.status-stack span{
  font-family:var(--font-mono);
  font-size:11.5px;
  padding:5px 9px;
  border-radius:5px;
  background:var(--teal-tint);
  border:1px solid #cdeae8;
  color:var(--teal);
}
.status-footer{
  margin-top:18px;
  display:flex;
  align-items:center;
  gap:9px;
  font-family:var(--font-mono);
  font-size:12.5px;
  color:var(--success);
  background:#EAFBF1;
  border:1px solid #CFF3DF;
  border-radius:8px;
  padding:10px 12px;
}
.status-footer .dot{
  width:8px; height:8px; border-radius:50%; background:var(--success);
  box-shadow:0 0 0 3px rgba(28,154,91,0.16);
  animation:pulse 2.4s ease-in-out infinite;
}

/* ---------- Marquee tech strip ---------- */
.techstrip{
  border-top:1px solid var(--border);
  border-bottom:1px solid var(--border);
  padding-block:22px;
  overflow:hidden;
  background:var(--surface);
}
.techstrip-track{
  display:flex;
  gap:48px;
  width:max-content;
  animation:scroll-left 34s linear infinite;
  font-family:var(--font-mono);
  font-size:13.5px;
  color:var(--ink-faint);
}
.techstrip-track span{ white-space:nowrap; }
.techstrip-track span b{ color:var(--ink-muted); font-weight:600; }
@keyframes scroll-left{
  from{ transform:translateX(0); }
  to{ transform:translateX(-50%); }
}

/* ---------- About ---------- */
.about-grid{
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap:clamp(32px, 5vw, 64px);
  align-items:start;
}
.about-text p{ color:var(--ink-muted); font-size:16px; }
.about-text p + p{ margin-top:16px; }
.about-text .highlight{ color:var(--ink); font-weight:600; }
.about-side{
  display:flex;
  flex-direction:column;
  gap:14px;
}
.fact{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-md);
  padding:16px 18px;
  display:flex;
  align-items:center;
  gap:14px;
  box-shadow:var(--shadow-sm);
}
.fact .num{
  font-family:var(--font-mono);
  font-size:22px;
  font-weight:700;
  color:var(--accent);
  min-width:64px;
}
.fact .label{ font-size:13.5px; color:var(--ink-muted); line-height:1.4; }

/* ---------- Diagram ---------- */
.diagram-wrap{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-lg);
  padding:clamp(18px, 3vw, 34px);
  overflow-x:auto;
  box-shadow:var(--shadow-sm);
}
.diagram-caption{
  margin-top:20px;
  display:grid;
  grid-template-columns:repeat(auto-fit, minmax(200px,1fr));
  gap:16px;
}
.diagram-caption .step{
  font-size:13.5px;
  color:var(--ink-muted);
  border-left:2px solid var(--accent);
  padding-left:12px;
}
.diagram-caption .step b{ color:var(--ink); display:block; font-family:var(--font-mono); font-size:12.5px; letter-spacing:0.04em; margin-bottom:4px; text-transform:uppercase; }

/* ---------- Case studies ---------- */
.cases{
  display:grid;
  grid-template-columns:repeat(2, 1fr);
  gap:22px;
}
.case-card{
  background:var(--surface);
  border:1px solid var(--border);
  border-top:3px solid var(--accent);
  border-radius:var(--radius-lg);
  padding:26px 26px 24px;
  display:flex;
  flex-direction:column;
  gap:16px;
  box-shadow:var(--shadow-sm);
  transition:border-color .2s ease, transform .2s ease, box-shadow .2s ease;
}
.case-card:hover{ transform:translateY(-3px); box-shadow:var(--shadow-md); }
.case-tag{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:0.1em;
  color:var(--amber);
  text-transform:uppercase;
  font-weight:600;
}
.case-card h3{ font-size:20px; color:var(--ink); }
.case-block{ font-size:14px; color:var(--ink-muted); }
.case-block b{ color:var(--ink); font-weight:600; display:block; margin-bottom:3px; font-size:12.5px; font-family:var(--font-mono); text-transform:uppercase; letter-spacing:0.04em; }
.case-stack{
  margin-top:auto;
  display:flex;
  flex-wrap:wrap;
  gap:7px;
  padding-top:6px;
}
.case-stack span{
  font-family:var(--font-mono);
  font-size:11px;
  padding:4px 9px;
  border-radius:5px;
  background:var(--accent-tint);
  border:1px solid #d7ddf9;
  color:var(--accent-dark);
}

/* ---------- Notable projects (extended portfolio) ---------- */
.proj-grid{
  display:grid;
  grid-template-columns:repeat(4, 1fr);
  gap:16px;
}
.proj-card{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-md);
  padding:18px 18px 16px;
  display:flex;
  flex-direction:column;
  gap:10px;
  box-shadow:var(--shadow-sm);
  transition:transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.proj-card:hover{ transform:translateY(-2px); box-shadow:var(--shadow-md); border-color:var(--border-strong); }
.proj-num{ font-family:var(--font-mono); font-size:11px; color:var(--ink-faint); }
.proj-card h4{ font-size:15.5px; color:var(--ink); }
.proj-card p{ font-size:13px; color:var(--ink-muted); line-height:1.5; }
.proj-stack{ display:flex; flex-wrap:wrap; gap:6px; margin-top:auto; padding-top:6px; }
.proj-stack span{
  font-family:var(--font-mono);
  font-size:10.5px;
  padding:3px 8px;
  border-radius:4px;
  background:var(--surface-2);
  border:1px solid var(--border);
  color:var(--ink-muted);
}

/* ---------- Skills ---------- */
.skills-grid{
  display:grid;
  grid-template-columns:repeat(3, 1fr);
  gap:18px;
}
.skill-card{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-md);
  padding:22px;
  box-shadow:var(--shadow-sm);
}
.skill-card .icon{
  width:34px; height:34px;
  border-radius:9px;
  background:var(--accent-tint);
  color:var(--accent-dark);
  display:flex; align-items:center; justify-content:center;
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-weight:700;
  font-size:14px;
}
.skill-card h4{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:0.08em;
  text-transform:uppercase;
  color:var(--ink);
  margin-bottom:14px;
}
.skill-card ul{ display:flex; flex-wrap:wrap; gap:8px; }
.skill-card li{
  font-size:13px;
  color:var(--ink-muted);
  background:var(--surface-2);
  border:1px solid var(--border);
  padding:6px 11px;
  border-radius:16px;
}

/* ---------- Timeline ---------- */
.timeline{
  position:relative;
  padding-left:28px;
  display:flex;
  flex-direction:column;
  gap:0;
}
.timeline::before{
  content:"";
  position:absolute;
  left:5px; top:6px; bottom:6px;
  width:1px;
  background:var(--border-strong);
}
.tl-item{
  position:relative;
  padding-bottom:34px;
}
.tl-item:last-child{ padding-bottom:0; }
.tl-item::before{
  content:"";
  position:absolute;
  left:-28px; top:5px;
  width:11px; height:11px;
  border-radius:50%;
  background:var(--surface);
  border:2px solid var(--accent);
}
.tl-item.current::before{ background:var(--accent); box-shadow:0 0 0 4px var(--accent-tint); }
.tl-date{
  font-family:var(--font-mono);
  font-size:12.5px;
  color:var(--amber);
  letter-spacing:0.04em;
  font-weight:600;
}
.tl-role{ font-size:19px; margin-top:6px; color:var(--ink); font-family:var(--font-display); font-weight:600; }
.tl-org{ font-size:14.5px; color:var(--ink-muted); margin-top:2px; }
.tl-desc{ font-size:14.5px; color:var(--ink-muted); margin-top:10px; max-width:64ch; }
.tl-stack{ display:flex; flex-wrap:wrap; gap:6px; margin-top:12px; }
.tl-stack span{
  font-family:var(--font-mono);
  font-size:11px;
  padding:4px 9px;
  border-radius:5px;
  background:var(--surface-2);
  border:1px solid var(--border);
  color:var(--ink-muted);
}

.freelance-note{
  margin-top:36px;
  padding:22px 24px;
  border:1px solid var(--border);
  background:var(--amber-tint);
  border-radius:var(--radius-md);
  font-size:14.5px;
  color:var(--ink-muted);
}
.freelance-note b{ color:var(--ink); font-family:var(--font-mono); font-size:12.5px; text-transform:uppercase; letter-spacing:0.06em; display:block; margin-bottom:8px; }

/* ---------- Education / languages ---------- */
.edu-grid{
  display:grid;
  grid-template-columns:1.3fr 1fr;
  gap:22px;
}
.edu-card, .lang-card{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-md);
  padding:22px 24px;
  box-shadow:var(--shadow-sm);
}
.edu-card h4, .lang-card h4{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:0.08em;
  text-transform:uppercase;
  color:var(--accent-dark);
  margin-bottom:12px;
}
.edu-card p{ font-size:15px; color:var(--ink); }
.edu-card span{ font-size:13.5px; color:var(--ink-muted); display:block; margin-top:6px; }
.lang-row{ display:flex; justify-content:space-between; font-size:14.5px; padding:8px 0; border-bottom:1px dashed var(--border); }
.lang-row:last-child{ border-bottom:none; }
.lang-row .lv{ color:var(--ink-muted); font-family:var(--font-mono); font-size:12.5px; }

/* ---------- Contact ---------- */
.contact{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius-lg);
  padding:clamp(28px, 5vw, 52px);
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:clamp(30px,5vw,54px);
  box-shadow:var(--shadow-md);
}
.contact-left h2{ font-size:clamp(24px,3vw,32px); }
.contact-left p{ margin-top:14px; color:var(--ink-muted); max-width:44ch; }
.contact-links{ margin-top:26px; display:flex; flex-direction:column; gap:12px; }
.contact-links a{
  display:flex; align-items:center; justify-content:space-between;
  padding:13px 16px;
  border:1px solid var(--border);
  border-radius:var(--radius-sm);
  font-family:var(--font-mono);
  font-size:13.5px;
  color:var(--ink-muted);
  transition:border-color .2s ease, color .2s ease, background .2s ease;
}
.contact-links a:hover{ border-color:var(--accent); color:var(--accent-dark); background:var(--accent-tint); }
.contact-links a span.arrow{ color:var(--accent); }

.form-group{ margin-bottom:16px; }
.form-group label{
  display:block;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:0.05em;
  text-transform:uppercase;
  color:var(--ink-faint);
  margin-bottom:8px;
}
.form-group input, .form-group textarea{
  width:100%;
  background:var(--bg);
  border:1px solid var(--border-strong);
  border-radius:var(--radius-sm);
  padding:12px 14px;
  color:var(--ink);
  font-family:var(--font-body);
  font-size:14.5px;
  resize:vertical;
}
.form-group input:focus, .form-group textarea:focus{
  outline:2px solid var(--accent);
  outline-offset:1px;
  border-color:var(--accent);
}
.form-status{ margin-top:12px; font-size:13.5px; color:var(--ink-muted); min-height:18px; }
.form-status.ok{ color:var(--success); }

/* ---------- Footer ---------- */
footer{
  border-top:1px solid var(--border);
  padding-block:32px;
  background:var(--surface);
}
.footer-row{
  display:flex;
  justify-content:space-between;
  align-items:center;
  flex-wrap:wrap;
  gap:12px;
  font-size:13.5px;
  color:var(--ink-faint);
}
.footer-row a:hover{ color:var(--accent); }
.footer-links{ display:flex; gap:20px; }

/* ---------- Reveal on scroll ---------- */
.reveal{
  opacity:0;
  transform:translateY(18px);
  transition:opacity .6s ease, transform .6s ease;
}
.reveal.in{ opacity:1; transform:translateY(0); }

/* ---------- Responsive ---------- */
@media (max-width: 980px){
  .proj-grid{ grid-template-columns:repeat(2, 1fr); }
}
@media (max-width: 920px){
  .nav-links{ display:none; }
  .nav-toggle{ display:inline-flex; }
  .hero-grid{ grid-template-columns:1fr; }
  .about-grid{ grid-template-columns:1fr; }
  .cases{ grid-template-columns:1fr; }
  .skills-grid{ grid-template-columns:1fr 1fr; }
  .edu-grid{ grid-template-columns:1fr; }
  .contact{ grid-template-columns:1fr; }
}
@media (max-width: 560px){
  .skills-grid{ grid-template-columns:1fr; }
  .proj-grid{ grid-template-columns:1fr; }
  .hero-flags{ flex-direction:column; gap:10px; }
}