/* =============================================================
   PERSONAL PORTFOLIO — style.css
   Update CSS custom properties below to change the colour
   scheme across the entire site.
   ============================================================= */

/* ── Custom Properties (theme colours) ── */
:root {
  --color-primary:    #4f46e5; /* indigo accent */
  --color-primary-h:  #4338ca; /* hover shade   */
  --color-linkedin:   #0a66c2;
  --color-bg-dark:    #0f172a; /* dark sections  */
  --color-bg-light:   #f8fafc; /* light sections */
  --color-bg-card:    #1e293b; /* cards in dark  */
  --color-text-dark:  #1e293b;
  --color-text-light: #f1f5f9;
  --color-text-muted: #94a3b8;
  --color-border:     #334155;
  --color-tag-bg:     rgba(79, 70, 229, 0.15);
  --color-tag-text:   #818cf8;

  --radius:   0.75rem;
  --shadow:   0 4px 24px rgba(0, 0, 0, 0.35);
  --transition: 0.25s ease;
  --max-width: 1100px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background-color: var(--color-bg-dark);
  color: var(--color-text-light);
  line-height: 1.7;
}

img { max-width: 100%; display: block; }

a { color: inherit; text-decoration: none; }

ul { list-style: none; }

/* ── Utility ── */
.container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.section { padding-block: 5rem; }

.section-light {
  background-color: var(--color-bg-light);
  color: var(--color-text-dark);
}

.section-dark {
  background-color: var(--color-bg-dark);
  color: var(--color-text-light);
}

.section-title {
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  font-weight: 700;
  margin-bottom: 3rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -0.4rem;
  width: 3rem;
  height: 3px;
  background: var(--color-primary);
  border-radius: 2px;
}

.highlight { color: var(--color-primary); }

.section-cta { text-align: center; margin-top: 3rem; }

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: 2px solid transparent;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform var(--transition);
}

.btn:active { transform: scale(0.97); }

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover { background: var(--color-primary-h); }

.btn-outline {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: transparent;
}
.btn-outline:hover { background: var(--color-primary); color: #fff; }

.btn-linkedin {
  background: var(--color-linkedin);
  color: #fff;
}
.btn-linkedin:hover { background: #085396; }

/* ── Navbar ── */
#navbar {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition);
}

#navbar.scrolled { box-shadow: 0 2px 20px rgba(0, 0, 0, 0.5); }

.nav-container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-text-light);
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active { color: var(--color-text-light); }

.nav-links a:hover::after,
.nav-links a.active::after { width: 100%; }

/* Hamburger toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text-light);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ── Hero ── */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: linear-gradient(160deg, #0f172a 0%, #1e293b 100%);
  padding-inline: 1.5rem;
  padding-top: 5rem;
}

.hero-content { max-width: 680px; }

#hero h1 {
  font-size: clamp(2.2rem, 6vw, 4rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 1rem;
}

.hero-tagline {
  font-size: clamp(1rem, 2vw, 1.3rem);
  color: var(--color-text-muted);
  margin-bottom: 2rem;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.hero-socials {
  display: flex;
  gap: 1.25rem;
  justify-content: center;
}

.hero-socials a {
  font-size: 1.5rem;
  color: var(--color-text-muted);
  transition: color var(--transition), transform var(--transition);
}

.hero-socials a:hover { color: var(--color-primary); transform: translateY(-3px); }

/* ── About ── */
.about-grid {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 3rem;
  align-items: start;
}

.about-photo {
  position: relative;
}

.about-photo img {
  width: 220px;
  height: 220px;
  object-fit: cover;
  border-radius: 50%;
  border: 4px solid var(--color-primary);
}

.about-photo-placeholder {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary) 0%, #818cf8 100%);
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  font-weight: 700;
  color: #fff;
  border: 4px solid var(--color-primary);
}

.about-photo img:not([src]),
.about-photo img[src=""],
.about-photo img.hidden { display: none; }

.about-photo img.hidden + .about-photo-placeholder,
.about-photo img:not([src]) + .about-photo-placeholder,
.about-photo img[src=""] + .about-photo-placeholder { display: flex; }

.about-text p { margin-bottom: 1rem; color: var(--color-text-dark); }

.about-details {
  margin-block: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.about-details li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--color-text-dark);
}

.about-details li i { color: var(--color-primary); min-width: 1rem; }

.about-details a { color: var(--color-primary); }
.about-details a:hover { text-decoration: underline; }

/* ── Timeline (shared by Experience & Education) ── */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0.4rem;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--color-primary);
  opacity: 0.3;
}

.timeline-item {
  position: relative;
  margin-bottom: 3rem;
}

.timeline-item:last-child { margin-bottom: 0; }

.timeline-marker {
  position: absolute;
  left: -1.7rem;
  top: 0.35rem;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
  border: 2px solid var(--color-bg-light);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.25);
}

/* Dark sections use dark bg for marker border */
.section-dark .timeline-marker { border-color: var(--color-bg-dark); }

.timeline-date {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.timeline-role {
  font-size: 1.15rem;
  font-weight: 700;
  margin-top: 0.25rem;
}

.timeline-company {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-muted);
  margin-bottom: 0.5rem;
}

.timeline-content p { margin-bottom: 0.75rem; }

.timeline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.5rem;
}

.timeline-tags li {
  background: var(--color-tag-bg);
  color: var(--color-tag-text);
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 500;
}

/* Light-section timeline text colours */
.section-light .timeline-content p,
.section-light .timeline-role { color: var(--color-text-dark); }

/* ── Cards Grid (Extracurriculars & Projects) ── */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: transform var(--transition), box-shadow var(--transition);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow);
}

/* Light-section cards */
.section-light .card {
  background: #fff;
  border-color: #e2e8f0;
}

.section-light .card h3 { color: var(--color-text-dark); }
.section-light .card p  { color: #475569; }

.card-icon {
  font-size: 1.75rem;
  color: var(--color-primary);
  margin-bottom: 1rem;
}

.card h3 { font-size: 1.1rem; margin-bottom: 0.5rem; }
.card p  { font-size: 0.9rem; color: var(--color-text-muted); }

/* Project-specific card */
.project-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.project-card-header > i {
  font-size: 1.75rem;
  color: var(--color-primary);
}

.project-links {
  display: flex;
  gap: 0.75rem;
}

.project-links a {
  font-size: 1.2rem;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

.project-links a:hover { color: var(--color-primary); }

/* ── LinkedIn section ── */
.linkedin-section {
  text-align: center;
  max-width: 600px;
}

.linkedin-icon {
  font-size: 4rem;
  color: var(--color-linkedin);
  margin-bottom: 1rem;
}

.linkedin-section h2 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  margin-bottom: 0.75rem;
}

.linkedin-section p {
  color: var(--color-text-muted);
  margin-bottom: 2rem;
}

/* ── Contact ── */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 4rem;
  align-items: start;
}

.contact-info p { color: var(--color-text-dark); margin-bottom: 1.5rem; }

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.contact-links a {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--color-primary);
  font-weight: 500;
  transition: color var(--transition);
}

.contact-links a i { font-size: 1.1rem; }
.contact-links a:hover { color: var(--color-primary-h); text-decoration: underline; }

/* Contact form */
.contact-form { display: flex; flex-direction: column; gap: 1.25rem; }

.form-group { display: flex; flex-direction: column; gap: 0.35rem; }

.form-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-dark);
}

.form-group input,
.form-group textarea {
  padding: 0.75rem 1rem;
  border: 1.5px solid #cbd5e1;
  border-radius: 0.5rem;
  font-family: inherit;
  font-size: 0.95rem;
  background: #fff;
  color: var(--color-text-dark);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

.form-group textarea { resize: vertical; min-height: 140px; }

.form-status {
  font-size: 0.88rem;
  font-weight: 600;
  min-height: 1.2em;
}

.form-status.success { color: #16a34a; }
.form-status.error   { color: #dc2626; }

/* ── Footer ── */
footer {
  background: #080f1e;
  padding-block: 2rem;
  border-top: 1px solid var(--color-border);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

footer p { color: var(--color-text-muted); font-size: 0.875rem; }

.footer-socials { display: flex; gap: 1.25rem; }

.footer-socials a {
  color: var(--color-text-muted);
  font-size: 1.2rem;
  transition: color var(--transition);
}

.footer-socials a:hover { color: var(--color-primary); }

.footer-admin-link {
  color: var(--color-border);
  font-size: 0.75rem;
  transition: color var(--transition);
  margin-left: 0.5rem;
}

.footer-admin-link:hover { color: var(--color-text-muted); }

/* ── Responsive ── */
@media (max-width: 768px) {
  /* Mobile nav */
  .nav-toggle { display: flex; }

  nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(15, 23, 42, 0.97);
    border-top: 1px solid var(--color-border);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  nav.open { max-height: 400px; }

  .nav-links {
    flex-direction: column;
    gap: 0;
    padding-block: 0.5rem;
  }

  .nav-links a {
    display: block;
    padding: 0.75rem 1.5rem;
  }

  /* About */
  .about-grid {
    grid-template-columns: 1fr;
    justify-items: center;
  }

  /* Contact */
  .contact-grid { grid-template-columns: 1fr; gap: 2rem; }
}

@media (max-width: 480px) {
  .section { padding-block: 3.5rem; }
  .hero-cta { flex-direction: column; align-items: center; }
  .footer-inner { flex-direction: column; text-align: center; }
}