/* ============================================================
   KIREN S — PORTFOLIO STYLESHEET
   Design: Premium minimal, Apple/Stripe/Linear-inspired
   Typography: Playfair Display (headings) + Inter (body)
   Palette: Near-white bg, ink text, electric blue accent
   ============================================================ */

/* ── CSS Variables ── */
:root {
  --bg:          #F8F9FA;
  --bg-alt:      #FFFFFF;
  --ink:         #0D0D0D;
  --ink-muted:   #5A5A5A;
  --ink-faint:   #A0A0A0;
  --accent:      #1B6EF3;
  --accent-dark: #0F4DB5;
  --accent-glow: rgba(27, 110, 243, 0.12);
  --border:      #E5E7EB;
  --border-soft: #F0F1F3;
  --shadow-sm:   0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:   0 4px 16px rgba(0,0,0,0.08), 0 1px 4px rgba(0,0,0,0.04);
  --shadow-lg:   0 12px 40px rgba(0,0,0,0.10);
  --radius:      12px;
  --radius-sm:   8px;
  --nav-h:       64px;
  --transition:  0.2s ease;

  /* Badge colours */
  --badge-primary-bg:   #EFF4FF;
  --badge-primary-txt:  #1B6EF3;
  --badge-secondary-bg: #F0FAF5;
  --badge-secondary-txt:#1A7F4B;
  --badge-green-bg:     #ECFDF5;
  --badge-green-txt:    #047857;
  --badge-orange-bg:    #FFF7ED;
  --badge-orange-txt:   #C2410C;
  --badge-purple-bg:    #F5F3FF;
  --badge-purple-txt:   #6D28D9;
  --badge-dark-bg:      #F3F4F6;
  --badge-dark-txt:     #374151;
}

/* Dark mode */
[data-theme="dark"] {
  --bg:          #0E0F11;
  --bg-alt:      #161719;
  --ink:         #F0F0F0;
  --ink-muted:   #9CA3AF;
  --ink-faint:   #4B5563;
  --accent:      #4D8EF7;
  --accent-dark: #3B7BE8;
  --accent-glow: rgba(77, 142, 247, 0.15);
  --border:      #2A2B2E;
  --border-soft: #1F2023;
  --shadow-sm:   0 1px 3px rgba(0,0,0,0.3);
  --shadow-md:   0 4px 16px rgba(0,0,0,0.4);
  --shadow-lg:   0 12px 40px rgba(0,0,0,0.5);
  --badge-primary-bg:   #1B2D4F;
  --badge-primary-txt:  #7DB4FF;
  --badge-secondary-bg: #1A2E24;
  --badge-secondary-txt:#5FD9A0;
  --badge-green-bg:     #022C22;
  --badge-green-txt:    #34D399;
  --badge-orange-bg:    #2C1800;
  --badge-orange-txt:   #FB923C;
  --badge-purple-bg:    #200E47;
  --badge-purple-txt:   #C4B5FD;
  --badge-dark-bg:      #1F2023;
  --badge-dark-txt:     #D1D5DB;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s, color 0.3s;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-dark); }

/* Focus styles for accessibility */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ── Container ── */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Navigation ── */
.nav-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(248, 249, 250, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  transition: background 0.3s, border-color 0.3s;
}

[data-theme="dark"] .nav-header {
  background: rgba(14, 15, 17, 0.88);
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-logo {
  font-family: 'Playfair Display', serif;
  font-size: 1.2rem;
  font-weight: 900;
  color: var(--ink);
  letter-spacing: -0.02em;
  margin-right: auto;
  flex-shrink: 0;
}
.nav-logo:hover { color: var(--accent); }

.nav-links {
  display: flex;
  list-style: none;
  gap: 6px;
}

.nav-links a {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--ink-muted);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
  background: var(--accent-glow);
}

.dark-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 5px 10px;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--ink-muted);
  flex-shrink: 0;
  transition: border-color var(--transition), color var(--transition);
}
.dark-toggle:hover { border-color: var(--accent); color: var(--accent); }

.icon-moon { display: none; }
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: inline; }

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  margin-left: auto;
}
.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ── Sections ── */
.section {
  padding: 96px 0;
}
.section-alt {
  background: var(--bg-alt);
}

.section-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-title {
  font-family: 'Playfair Display', serif;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  color: var(--ink);
  line-height: 1.2;
  margin-bottom: 48px;
  letter-spacing: -0.02em;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  border: 1.5px solid transparent;
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn-primary:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
  border-color: var(--border);
}
.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}

/* ── Hero ── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: calc(var(--nav-h) + 48px) 24px 80px;
  text-align: center;
  position: relative;
  background:
    radial-gradient(ellipse 60% 50% at 50% 0%, var(--accent-glow), transparent 70%);
}

.hero-eyebrow {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.1s;
}

.hero-name {
  font-family: 'Playfair Display', serif;
  font-size: clamp(3.5rem, 10vw, 7rem);
  font-weight: 900;
  letter-spacing: -0.04em;
  line-height: 1;
  color: var(--ink);
  margin-bottom: 24px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.25s;
}

.hero-tagline {
  font-size: clamp(1rem, 2.5vw, 1.3rem);
  color: var(--ink-muted);
  line-height: 1.6;
  max-width: 520px;
  margin: 0 auto 32px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.4s;
}

.hero-pills {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  list-style: none;
  margin-bottom: 40px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.55s;
}

.hero-pills li {
  font-size: 0.78rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 20px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  color: var(--ink-muted);
  letter-spacing: 0.02em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.7s;
}

.hero-scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0;
  animation: fadeIn 1s ease forwards 1.2s;
}
.hero-scroll-hint span {
  display: block;
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, var(--ink-faint), transparent);
  margin: 0 auto;
  animation: scrollLine 1.5s ease-in-out infinite;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; } to { opacity: 1; }
}
@keyframes scrollLine {
  0%, 100% { transform: scaleY(1); opacity: 1; }
  50% { transform: scaleY(0.5); opacity: 0.4; }
}

/* ── About ── */
.about-grid {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 56px;
  align-items: start;
}

.about-photo {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
}

.photo-placeholder {
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-glow), var(--border-soft));
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Playfair Display', serif;
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--accent);
}

.about-lead {
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--ink);
  margin-bottom: 16px;
  line-height: 1.65;
}

.about-body p {
  color: var(--ink-muted);
  margin-bottom: 16px;
}

.about-meta {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 36px;
  padding-top: 36px;
  border-top: 1px solid var(--border);
}

.meta-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.meta-value {
  font-family: 'Playfair Display', serif;
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
}

.meta-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--ink-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ── Skills ── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 28px;
}

.skill-group {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

[data-theme="dark"] .skill-group {
  background: var(--bg-alt);
}

.skill-group-title {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 14px;
}

/* ── Badges ── */
.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.badge {
  display: inline-flex;
  align-items: center;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 20px;
  white-space: nowrap;
}

.badge-primary   { background: var(--badge-primary-bg);   color: var(--badge-primary-txt); }
.badge-secondary { background: var(--badge-secondary-bg); color: var(--badge-secondary-txt); }
.badge-green     { background: var(--badge-green-bg);     color: var(--badge-green-txt); }
.badge-orange    { background: var(--badge-orange-bg);    color: var(--badge-orange-txt); }
.badge-purple    { background: var(--badge-purple-bg);    color: var(--badge-purple-txt); }
.badge-dark      { background: var(--badge-dark-bg);      color: var(--badge-dark-txt); }

.badges.small .badge { font-size: 0.7rem; padding: 3px 8px; }

/* ── Timeline (Experience) ── */
.timeline {
  list-style: none;
  position: relative;
  padding-left: 28px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0; bottom: 0;
  width: 1px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: 36px;
}
.timeline-item:last-child { margin-bottom: 0; }

.timeline-dot {
  position: absolute;
  left: -24px;
  top: 20px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg);
  box-shadow: 0 0 0 1px var(--accent);
  transition: background var(--transition);
}

[data-theme="dark"] .timeline-dot {
  border-color: var(--bg-alt);
}

.timeline-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}
.timeline-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.timeline-company {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink);
}

.timeline-role {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
  margin-top: 2px;
}

.timeline-date {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--ink-faint);
  white-space: nowrap;
  flex-shrink: 0;
  padding: 4px 10px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 20px;
}

[data-theme="dark"] .timeline-date {
  background: var(--bg);
}

.timeline-desc {
  font-size: 0.88rem;
  color: var(--ink-muted);
  margin-bottom: 12px;
  line-height: 1.6;
}

.timeline-achievements {
  list-style: none;
  margin-bottom: 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.timeline-achievements li {
  font-size: 0.82rem;
  color: var(--ink-muted);
  padding-left: 16px;
  position: relative;
}
.timeline-achievements li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.78rem;
}

.timeline-link {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
}
.timeline-link:hover { text-decoration: underline; }

/* ── Projects ── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}

.project-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}
.project-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
  border-color: var(--accent);
}

[data-theme="dark"] .project-card {
  background: var(--bg-alt);
}

.project-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 8px;
}

.project-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
}

.project-role {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-glow);
  padding: 3px 8px;
  border-radius: 20px;
  white-space: nowrap;
  flex-shrink: 0;
}

.project-desc {
  font-size: 0.85rem;
  color: var(--ink-muted);
  line-height: 1.6;
  flex: 1;
}

.project-achievements {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.project-achievements li {
  font-size: 0.78rem;
  color: var(--ink-muted);
  padding-left: 14px;
  position: relative;
}
.project-achievements li::before {
  content: '·';
  position: absolute;
  left: 4px;
  color: var(--accent);
  font-weight: 700;
}

/* ── Highlights ── */
.highlights-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.highlight-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 20px;
  transition: box-shadow var(--transition), transform var(--transition);
}
.highlight-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.highlight-icon {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.highlight-card h3 {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.highlight-card p {
  font-size: 0.82rem;
  color: var(--ink-muted);
  line-height: 1.55;
}

/* ── Education Timeline ── */
.edu-timeline {
  list-style: none;
  position: relative;
  padding-left: 28px;
}
.edu-timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0; bottom: 0;
  width: 1px;
  background: var(--border);
}

.edu-item {
  position: relative;
  margin-bottom: 28px;
}
.edu-item:last-child { margin-bottom: 0; }

.edu-dot {
  position: absolute;
  left: -24px;
  top: 16px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg-alt);
  border: 2px solid var(--accent);
}

.edu-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  display: grid;
  grid-template-columns: 60px 1fr auto;
  gap: 0 20px;
  align-items: center;
}

.edu-year {
  font-family: 'Playfair Display', serif;
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
}

.edu-degree {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 2px;
}

.edu-school {
  font-size: 0.8rem;
  color: var(--ink-muted);
}

.edu-grade {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--ink-faint);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 4px 12px;
  white-space: nowrap;
}

/* ── Contact ── */
.contact-intro {
  font-size: 1.05rem;
  color: var(--ink-muted);
  margin-bottom: 40px;
  max-width: 480px;
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 16px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  color: var(--ink);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}
.contact-card:hover:not(.no-link) {
  border-color: var(--accent);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
  color: var(--ink);
}

.contact-icon {
  font-size: 1.3rem;
  flex-shrink: 0;
}

.contact-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-faint);
  display: block;
}

.contact-value {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--ink);
  word-break: break-word;
}

/* ── Footer ── */
.footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 24px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: var(--ink-faint);
  flex-wrap: wrap;
  gap: 8px;
}

/* ── Back to Top ── */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition), transform var(--transition);
  z-index: 500;
}
.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}
.back-to-top:hover {
  transform: translateY(-3px);
  color: #fff;
}

/* ── Print Styles ── */
@media print {
  .nav-header, .hero-scroll-hint, .back-to-top, .dark-toggle, .nav-hamburger { display: none !important; }
  .section { padding: 32px 0; }
  body { background: white; color: black; }
  .timeline-card, .project-card, .highlight-card, .contact-card {
    box-shadow: none;
    border: 1px solid #ddd;
  }
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-photo { position: static; display: flex; justify-content: center; }
  .photo-placeholder { width: 120px; height: 120px; font-size: 1.8rem; }
  .about-meta { grid-template-columns: repeat(2, 1fr); }
  .edu-card { grid-template-columns: 50px 1fr; }
  .edu-grade { grid-column: 2; margin-top: -4px; width: fit-content; }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    background: var(--bg-alt);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 12px 16px 20px;
    gap: 4px;
  }
  .nav-links.open { display: flex; }
  .nav-hamburger { display: flex; }
  .dark-toggle { order: 3; }
  .section { padding: 64px 0; }
  .skills-grid { grid-template-columns: 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
  .highlights-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-actions { flex-direction: column; align-items: center; }
  .timeline-header { flex-direction: column; }
}

@media (max-width: 480px) {
  .highlights-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .about-meta { grid-template-columns: repeat(2, 1fr); }
  .edu-card { grid-template-columns: 1fr; gap: 4px; }
  .edu-year { font-size: 1rem; }
}