:root {
  --bg: #150a24;
  --surface: #211138;
  --text: #f1ecfb;
  --muted: #b3a2d1;
  --accent: #a970ff;
  --accent-2: #4d7cff;
  --velvet: #3d1e63;
  --border: #3d2a5c;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

a {
  color: var(--accent);
}

.hero {
  padding: 1.5rem 1rem 4rem;
  background: linear-gradient(145deg, #2a1650, #150a24 65%);
  border-bottom: 1px solid var(--border);
}

/* Hamburger button that opens the side navigation */
.menu-toggle {
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 70;
  width: 46px;
  height: 46px;
  border-radius: 0.6rem;
  border: 1px solid var(--border);
  background: var(--surface);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.35);
}

.menu-toggle span {
  width: 20px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

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

.menu-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

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

/* Backdrop shown behind the open side navigation */
.sidenav-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 4, 20, 0.6);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 65;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.sidenav-backdrop.is-active {
  opacity: 1;
  visibility: visible;
}

/* Side navigation drawer */
.side-nav {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: min(280px, 80vw);
  background: var(--surface);
  border-right: 1px solid var(--border);
  z-index: 68;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  padding: 4.5rem 1.2rem 1.5rem;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  box-shadow: 10px 0 30px rgba(0, 0, 0, 0.4);
}

.side-nav.is-open {
  transform: translateX(0);
}

.side-nav a {
  text-decoration: none;
  color: var(--muted);
  font-weight: 600;
  padding: 0.7rem 0.6rem;
  border-radius: 0.5rem;
  transition: background 0.2s ease, color 0.2s ease;
}

.side-nav a:hover,
.side-nav a.active {
  background: var(--velvet);
  color: var(--text);
}

.side-nav-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  font-size: 1.3rem;
  line-height: 1;
  cursor: pointer;
}

.hero-content {
  max-width: 1024px;
  margin: 3rem auto 0;
}

.hero-top {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.profile-photo {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid transparent;
  background: linear-gradient(var(--bg), var(--bg)) padding-box,
    linear-gradient(135deg, var(--accent), var(--accent-2)) border-box;
  box-shadow: 0 0 0 4px rgba(169, 112, 255, 0.15);
}

.kicker {
  color: var(--accent-2);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin: 0;
}

h1 {
  font-size: clamp(2rem, 6vw, 3rem);
  margin: 0.5rem 0;
}

.subtitle {
  color: var(--muted);
  max-width: 700px;
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  gap: 0.8rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

.btn {
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  padding: 0.7rem 1rem;
  border-radius: 0.5rem;
  text-decoration: none;
  font-weight: 600;
}

.btn.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #0d0620;
  border-color: transparent;
}

main {
  max-width: 1024px;
  margin: 0 auto;
  padding: 0 1rem 4rem;
}

.section {
  padding-top: 2.5rem;
}

h2 {
  font-size: 1.7rem;
  margin-bottom: 0.7rem;
}

p {
  line-height: 1.7;
}

.timeline {
  display: grid;
  gap: 1rem;
}

.timeline-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 0.8rem;
  padding: 1rem 1.1rem;
}

.timeline-item h3 {
  margin-top: 0;
}

.time {
  color: var(--muted);
  font-size: 0.95rem;
  margin-top: -0.35rem;
}

.section-head p {
  color: var(--muted);
  margin-top: 0;
}

.filters {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
  margin: 1rem 0 1.5rem;
}

.filter-btn {
  border: 1px solid var(--border);
  background: var(--velvet);
  color: var(--text);
  border-radius: 999px;
  padding: 0.45rem 0.9rem;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.filter-btn.active {
  border-color: var(--accent-2);
  color: #ffffff;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}

.project-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.project-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.8rem;
  padding: 1rem;
  cursor: pointer;
  transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease,
    opacity 0.6s ease;
}

.project-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

/* Scroll-reveal animation for project cards */
.project-card.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s ease, transform 0.6s ease, border-color 0.2s ease,
    box-shadow 0.2s ease;
}

.project-card.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Generic scroll-reveal used across every section */
.reveal-section {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal-section.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-item {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal-item.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- About: fade + gentle scale-up --- */
#about.reveal-section {
  transform: scale(0.94);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

#about.reveal-section.is-visible {
  transform: scale(1);
}

/* --- Experience: timeline items slide in from alternating sides --- */
#experience .reveal-item {
  transform: translateX(-40px);
  transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

#experience .reveal-item:nth-child(even) {
  transform: translateX(40px);
}

#experience .reveal-item.is-visible {
  transform: translateX(0);
}

/* --- Projects: heading/intro rises up while cards keep their own pop-in --- */
#projects.reveal-section {
  transform: translateY(0);
  transition: opacity 0.5s ease;
}

#projects .section-head {
  opacity: 0;
  transform: translateY(-18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

#projects.reveal-section.is-visible .section-head {
  opacity: 1;
  transform: translateY(0);
}

/* --- Skills: groups flip/rotate into place --- */
#skills .reveal-item {
  transform: rotateX(-35deg) translateY(16px);
  transform-origin: top center;
  transition: opacity 0.6s ease, transform 0.6s ease;
}

#skills.reveal-section {
  perspective: 800px;
}

#skills .reveal-item.is-visible {
  transform: rotateX(0deg) translateY(0);
}

/* --- Contact: zoom in from center --- */
#contact.reveal-section {
  transform: scale(0.85);
  transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

#contact.reveal-section.is-visible {
  transform: scale(1);
}

/* Hero intro animation on page load */
.hero-top,
.hero-actions,
.menu-toggle {
  opacity: 0;
  animation: heroFadeUp 0.8s ease forwards;
}

.menu-toggle {
  animation-delay: 0.05s;
}

.hero-top {
  animation-delay: 0.2s;
}

.hero-actions {
  animation-delay: 0.4s;
}

@keyframes heroFadeUp {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal-section,
  .reveal-item,
  .project-card.reveal,
  .hero-top,
  .hero-actions,
  .menu-toggle,
  .side-nav {
    opacity: 1 !important;
    transform: none !important;
    animation: none !important;
    transition: none !important;
  }
}

/* Expanded project card ("lightbox" for a project) */
.project-card.is-expanded {
  position: fixed;
  top: 50%;
  left: 50%;
  width: min(720px, 92vw);
  max-height: 86vh;
  overflow-y: auto;
  z-index: 55;
  cursor: default;
  box-shadow: 0 30px 70px rgba(0, 0, 0, 0.6);
  animation: cardPopIn 0.32s ease forwards;
}

.project-card.is-expanded:hover {
  transform: translate(-50%, -50%);
}

@keyframes cardPopIn {
  from {
    transform: translate(-50%, -50%) scale(0.88);
    opacity: 0;
  }
  to {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
}

/* Blurred backdrop shown behind an expanded project card */
.card-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 4, 20, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 45;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.card-backdrop.is-active {
  opacity: 1;
  visibility: visible;
}

/* Shared "back" button for closing project/diagram lightboxes */
.lightbox-back {
  position: fixed;
  top: 1.2rem;
  left: 1.2rem;
  z-index: 60;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.55rem 1.1rem;
  border-radius: 999px;
  cursor: pointer;
  display: none;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.4);
  opacity: 0;
  transform: translateX(-8px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.lightbox-back.is-active {
  display: inline-flex;
  opacity: 1;
  transform: translateX(0);
}

.lightbox-back:hover {
  border-color: var(--accent);
}

.project-card h3 {
  margin-top: 0;
}

.stack {
  font-size: 0.9rem;
  color: var(--accent-2);
  font-weight: 600;
}

.project-subsection {
  margin-top: 1rem;
}

.project-subtitle {
  margin: 0 0 0.55rem;
  font-size: 1rem;
  color: var(--accent);
}

.skills-group {
  border-left: 3px solid var(--accent-2);
  padding-left: 0.8rem;
  margin-bottom: 1rem;
}

.diagram-card {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.8rem;
  overflow: hidden;
  cursor: zoom-in;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.diagram-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.35);
}

.diagram-card img {
  width: 100%;
  display: block;
  background: #ffffff;
}

.diagram-card figcaption {
  padding: 0.8rem 0.9rem;
  color: var(--muted);
  font-size: 0.95rem;
  border-top: 1px solid var(--border);
}

/* Expanded diagram (image + caption only) */
.diagram-card.is-expanded {
  position: fixed;
  top: 50%;
  left: 50%;
  width: min(880px, 92vw);
  max-height: 88vh;
  overflow-y: auto;
  z-index: 55;
  cursor: default;
  box-shadow: 0 30px 70px rgba(0, 0, 0, 0.6);
  animation: cardPopIn 0.32s ease forwards;
}

.diagram-card.is-expanded:hover {
  transform: translate(-50%, -50%);
  box-shadow: 0 30px 70px rgba(0, 0, 0, 0.6);
}

body.lightbox-open {
  overflow: hidden;
}

.skills-group h3 {
  margin-bottom: 0.2rem;
}

.skills-group p {
  margin-top: 0;
}

.contact-list {
  list-style: none;
  padding-left: 0;
}

.contact-list li {
  margin-bottom: 0.4rem;
}

.footer {
  border-top: 1px solid var(--border);
  padding: 1rem;
  text-align: center;
  color: var(--muted);
}

.is-hidden {
  display: none;
}