/* ═══════════════════════════════════════════════════════════════
   SAURABH KUMAR DEY — OFFICIAL SITE DESIGN SYSTEM
   Founder, Entrepreneur & Author · saurabhdey.in
   ═══════════════════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,400;0,600;0,700;1,400;1,600&family=DM+Mono:wght@400;500&family=Inter:wght@300;400;500;600;700&family=Syne:wght@600;700;800&display=swap');

:root {
  --bg: #07070c;
  --bg-card: #0e0e17;
  --bg-card-hover: #151522;
  --text-main: #eae5dd;
  --text-muted: rgba(234, 229, 221, 0.65);
  --text-dim: rgba(234, 229, 221, 0.4);
  --accent: #c0392b;
  --accent-glow: rgba(192, 57, 43, 0.35);
  --border: rgba(192, 57, 43, 0.18);
  --border-strong: rgba(192, 57, 43, 0.35);
  --nav-bg: rgba(7, 7, 12, 0.88);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 24px;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-serif: 'Cormorant Garamond', Georgia, serif;
  --font-mono: 'DM Mono', monospace;
  --font-display: 'Syne', sans-serif;
}

html.light {
  --bg: #f8f6f2;
  --bg-card: #ffffff;
  --bg-card-hover: #f1ede6;
  --text-main: #181512;
  --text-muted: #5a544c;
  --text-dim: #8a8277;
  --accent: #c0392b;
  --accent-glow: rgba(192, 57, 43, 0.2);
  --border: rgba(192, 57, 43, 0.22);
  --border-strong: rgba(192, 57, 43, 0.45);
  --nav-bg: rgba(248, 246, 242, 0.92);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg);
  color: var(--text-main);
  font-family: var(--font-sans);
  font-weight: 300;
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s ease, color 0.3s ease;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

/* ─── CONTAINER & LAYOUT ─── */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4rem 0;
  border-top: 1px solid var(--border);
}

.section-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 1.2rem;
  color: var(--text-main);
}

.badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--accent);
  background: rgba(192, 57, 43, 0.1);
  border: 1px solid var(--border);
  padding: 0.25rem 0.75rem;
  border-radius: 50px;
}

/* ─── HEADER & NAVIGATION ─── */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 0.9rem 0;
}

.header-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: var(--text-main);
}

.brand-title {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--accent);
  letter-spacing: 1px;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.4rem;
}

.site-nav a {
  font-size: 0.88rem;
  font-weight: 400;
  color: var(--text-muted);
  transition: color 0.2s ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--accent);
  font-weight: 500;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.theme-toggle,
.menu-toggle {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
  color: var(--text-main);
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.95rem;
  transition: all 0.2s ease;
}

.theme-toggle:hover,
.menu-toggle:hover {
  border-color: var(--accent);
  background: var(--accent-glow);
}

.menu-toggle {
  display: none;
}

.mobile-nav {
  display: none;
  flex-direction: column;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  padding: 1.2rem 1.5rem;
  gap: 0.9rem;
}

.mobile-nav.open {
  display: flex;
}

.mobile-nav a {
  font-size: 1.05rem;
  color: var(--text-main);
  padding: 0.4rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

/* ─── BUTTONS ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.5px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.25s ease;
  text-decoration: none;
}

.btn-primary {
  background: var(--accent);
  color: #ffffff;
  border: 1px solid var(--accent);
  box-shadow: 0 4px 15px var(--accent-glow);
}

.btn-primary:hover {
  background: #a93226;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px var(--accent-glow);
}

.btn-secondary {
  background: transparent;
  color: var(--text-main);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(192, 57, 43, 0.06);
}

/* ─── PROFILE HERO ─── */
.profile-hero {
  padding: 4rem 0 3rem;
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 3rem;
  align-items: center;
}

.profile-img-wrap {
  text-align: center;
}

.profile-img {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--accent);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.profile-meta h1 {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -1px;
}

/* ─── BIO TIER TABS ─── */
.bio-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.5rem;
}

.bio-tab-btn {
  background: none;
  border: none;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.bio-tab-btn.active {
  color: var(--accent);
  background: rgba(192, 57, 43, 0.1);
  font-weight: 600;
}

.bio-panel {
  display: none;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
}

.bio-panel.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

.copy-btn {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  color: var(--text-main);
  padding: 0.5rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.copy-btn:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* ─── TIMELINE ─── */
.timeline {
  position: relative;
  padding-left: 2rem;
  border-left: 2px solid var(--border);
  margin: 2rem 0;
}

.timeline-item {
  position: relative;
  margin-bottom: 2.2rem;
}

.timeline-dot {
  position: absolute;
  left: -2.45rem;
  top: 0.3rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

.timeline-year {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  letter-spacing: 1px;
  margin-bottom: 0.2rem;
}

.timeline-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
  color: var(--text-main);
}

.timeline-desc {
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.7;
}

/* ─── CARDS & GRIDS ─── */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.3);
}

.card-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
  display: block;
}

.card-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: var(--text-main);
}

.card-body {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
  margin-bottom: 1.2rem;
  flex-grow: 1;
}

.card-link {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.card-link:hover {
  text-decoration: underline;
}

/* ─── FOOTER ─── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 3.5rem 0;
  text-align: center;
  background: rgba(0, 0, 0, 0.4);
}

.footer-inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.footer-attr {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-main);
  margin-bottom: 1.2rem;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 1.2rem;
  flex-wrap: wrap;
  margin-bottom: 1.4rem;
}

.footer-nav a {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-nav a:hover {
  color: var(--accent);
}

/* ─── RESPONSIVE BREAKPOINTS ─── */
@media (max-width: 900px) {
  .site-nav {
    display: none;
  }
  .menu-toggle {
    display: block;
  }
  .profile-hero {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 2rem;
  }
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }
  .card[style*="grid-template-columns"] {
    grid-template-columns: 1fr !important;
  }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}