/* ============================================================
   style.css  |  Base — Variables · Reset · Typography · Utilities
   Biswanath Mahapatra Portfolio
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* ── CSS Variables ── */
:root {
  /* Backgrounds */
  --bg-primary:   #ffffff;
  --bg-secondary: #f5f7ff;
  --bg-tertiary:  #eef1fc;
  --bg-card:      #ffffff;

  /* Accent — Indigo / Violet */
  --accent-primary:   #4f46e5;
  --accent-secondary: #7c3aed;
  --accent-cyan:      #0891b2;
  --accent-light:     #ede9fe;
  --accent-mid:       #c4b5fd;

  /* Text */
  --text-primary:   #111827;
  --text-secondary: #374151;
  --text-muted:     #6b7280;
  --text-subtle:    #9ca3af;

  /* Borders */
  --border-light:  #e5e7eb;
  --border-mid:    #d1d5db;
  --border-accent: rgba(79,70,229,0.25);

  /* Shadows */
  --shadow-sm:   0 1px 3px rgba(0,0,0,0.06);
  --shadow-md:   0 4px 16px rgba(79,70,229,0.08), 0 1px 3px rgba(0,0,0,0.06);
  --shadow-lg:   0 12px 40px rgba(79,70,229,0.12), 0 2px 8px rgba(0,0,0,0.06);
  --shadow-card: 0 2px 12px rgba(79,70,229,0.08);

  /* Fonts */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Spacing */
  --space-xs:  4px;
  --space-sm:  8px;
  --space-md:  16px;
  --space-lg:  24px;
  --space-xl:  40px;
  --space-2xl: 64px;
  --space-3xl: 96px;

  /* Radius */
  --radius-sm:   6px;
  --radius-md:   10px;
  --radius-lg:   16px;
  --radius-xl:   24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition:      0.22s cubic-bezier(0.4,0,0.2,1);
  --transition-slow: 0.4s  cubic-bezier(0.4,0,0.2,1);

  /* Layout */
  --nav-height: 68px;
  --max-width:  1100px;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  max-width: 100%;
}

img  { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
a  { color: var(--accent-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-secondary); }
button { font-family: var(--font-sans); cursor: pointer; border: none; background: none; }
input, textarea, select { font-family: var(--font-sans); font-size: 16px; }

/* ── Typography ── */
h1,h2,h3,h4,h5,h6 { line-height: 1.2; font-weight: 700; color: var(--text-primary); }
h1 { font-size: clamp(40px, 7vw, 68px); letter-spacing: -1.5px; }
h2 { font-size: clamp(28px, 4vw, 40px); letter-spacing: -0.8px; }
h3 { font-size: clamp(18px, 2.5vw, 22px); letter-spacing: -0.3px; }
h4 { font-size: 18px; }
p  { color: var(--text-secondary); }
.mono { font-family: var(--font-mono); }

/* ── Layout ── */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

section { padding: var(--space-3xl) 0; }
section:nth-child(even) { background-color: var(--bg-primary); }
section:nth-child(odd)  { background-color: var(--bg-secondary); }

/* Grid helpers */
.grid-2 { display: grid; grid-template-columns: repeat(2,1fr); gap: var(--space-lg); }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: var(--space-lg); }
.grid-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: var(--space-lg); }

/* ── Section Header ── */
.section-header { text-align: center; margin-bottom: var(--space-2xl); }

.section-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent-primary);
  background: var(--accent-light);
  padding: 5px 14px;
  border-radius: var(--radius-full);
  margin-bottom: var(--space-md);
  transition: background var(--transition), color var(--transition);
}

.section-title { margin-bottom: var(--space-md); }
.section-title span { color: var(--accent-primary); }

.section-subtitle {
  font-size: 17px;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto;
}

/* ── Card ── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-card);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-accent);
}
.card:focus-within {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-md);
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 11px 24px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.2px;
  transition: all var(--transition);
  white-space: nowrap;
}
.btn:active { transform: scale(0.97) translateY(0) !important; }

.btn-primary {
  background: var(--accent-primary);
  color: #fff;
  box-shadow: 0 2px 12px rgba(79,70,229,0.3);
}
.btn-primary:hover {
  background: var(--accent-secondary);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(79,70,229,0.35);
}

.btn-outline {
  background: transparent;
  color: var(--accent-primary);
  border: 1.5px solid var(--border-accent);
}
.btn-outline:hover {
  background: var(--accent-light);
  color: var(--accent-primary);
  border-color: var(--accent-primary);
  transform: translateY(-2px);
}

.btn-sm { padding: 7px 16px; font-size: 13px; }

/* ── Badge ── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  background: var(--accent-light);
  color: var(--accent-secondary);
  border: 1px solid rgba(124,58,237,0.2);
  white-space: nowrap;
}
.badge-blue  { background:#eff6ff; color:#1d4ed8; border-color:rgba(29,78,216,0.2); }
.badge-green { background:#f0fdf4; color:#166534; border-color:rgba(22,101,52,0.2); }
.badge-amber { background:#fffbeb; color:#92400e; border-color:rgba(146,64,14,0.2); }
.badge-red   { background:#fef2f2; color:#991b1b; border-color:rgba(153,27,27,0.2); }
.badge-cyan  { background:#ecfeff; color:#155e75; border-color:rgba(21,94,117,0.2); }
.badge-gray  { background:#f9fafb; color:#374151; border-color:rgba(55,65,81,0.2); }

/* ── Scroll Reveal ── */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s cubic-bezier(0.4,0,0.2,1),
              transform 0.6s cubic-bezier(0.4,0,0.2,1);
}
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

/* ── Utilities ── */
.gradient-text {
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 50%, var(--accent-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.accent-line {
  display: block;
  width: 48px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-cyan));
  border-radius: var(--radius-full);
  margin: var(--space-md) 0;
}
.accent-line.centered { margin: var(--space-md) auto; }

@keyframes float {
  0%,100% { transform: translateY(0); }
  50%      { transform: translateY(-10px); }
}
.float-anim { animation: float 5s ease-in-out infinite; }

@keyframes page-enter {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
body.ready { animation: page-enter 0.5s ease forwards; }

/* Lazy image fade-in */
img { opacity: 0; transition: opacity 0.4s ease; }
img.loaded { opacity: 1; }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-secondary); }
::-webkit-scrollbar-thumb { background: var(--accent-mid); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent-primary); }
::selection { background: var(--accent-light); color: var(--accent-secondary); }
:focus-visible { outline: 2px solid var(--accent-primary); outline-offset: 3px; border-radius: 3px; }

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .container { padding: 0 var(--space-lg); }
  .grid-3 { grid-template-columns: repeat(2,1fr); }
  .grid-4 { grid-template-columns: repeat(2,1fr); }
  section  { padding: var(--space-2xl) 0; }
}

@media (max-width: 767px) {
  .container { padding: 0 var(--space-md); }
  .grid-2 { grid-template-columns: 1fr; }
  .grid-3 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2,1fr); }
  section  { padding: 60px 0; }
  :root    { --nav-height: 60px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
  .reveal { opacity: 1; transform: none; }
  html    { scroll-behavior: auto; }
}

/* ── Print ── */
@media print {
  #navbar, #back-to-top, #loading-screen,
  .hero-badge-float, .hero-photo-ring::before,
  .hero-photo-ring::after { display: none !important; }
  body { background: white; color: black; }
  section { padding: 20px 0; page-break-inside: avoid; }
}