/* ============================================
   RIVER FLOW PORTFOLIO - HORIZONTAL SNAP
   Minimal, seamless, snap-to-page
   ============================================ */

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

:root {
  --deep: #0a0f14;
  --slate: #1a2332;
  --cyan: #06b6d4;
  --cyan-light: #22d3ee;
  --white: #ffffff;
  --mist: #f8fafc;
  --fog: #cbd5e1;
  --font: 'Sora', sans-serif;
  --flow: cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  margin: 0;
  padding: 0;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.7;
  color: var(--mist);
  background: var(--deep);
  overflow: hidden;
  height: 100vh;
  width: 100vw;
}

h1, h2, h3 { font-family: var(--font); line-height: 1.2; color: var(--white); }
h1 { font-size: clamp(2.8rem, 7vw, 5rem); font-weight: 800; letter-spacing: -0.03em; }
h2 { font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 700; letter-spacing: -0.02em; margin-bottom: 2rem; }
h3 { font-size: clamp(1.1rem, 2vw, 1.4rem); font-weight: 600; margin-bottom: 0.5rem; }
a { color: inherit; text-decoration: none; }

/* === MINIMAL TOP NAVIGATION === */
.nav-minimal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  display: flex;
  justify-content: center;
  gap: 3rem;
  padding: 1.5rem 2rem;
  pointer-events: none;
}

.nav-link {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: rgba(248, 250, 252, 0.5);
  transition: color 400ms var(--flow);
  pointer-events: auto;
  cursor: pointer;
}

.nav-link:hover { color: rgba(248, 250, 252, 0.85); }
.nav-link.active { color: var(--cyan); }

/* === SCROLL CONTAINER === */
.scroll-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  overflow-x: scroll;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  scroll-snap-type: x mandatory;
}

/* Hide scrollbar */
.scroll-container::-webkit-scrollbar { display: none; }
.scroll-container { scrollbar-width: none; -ms-overflow-style: none; }

/* === MAIN HORIZONTAL TRACK === */
.horizontal-track {
  display: flex;
  flex-direction: row;
  height: 100vh;
  width: 500vw; /* 5 sections x 100vw each */
}

/* === SECTIONS === */
.section {
  width: 100vw;
  min-width: 100vw;
  height: 100vh;
  flex-shrink: 0;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 65px 6vw 30px;
  overflow: hidden;
  scroll-snap-align: start;
  scroll-snap-stop: always;
}

/* Background with seamless blend - MORE VISIBLE */
.section-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0.35;
}

.section-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: 
    linear-gradient(90deg, 
      rgba(10, 15, 20, 0.3) 0%, 
      rgba(10, 15, 20, 0.05) 15%,
      rgba(10, 15, 20, 0.05) 85%,
      rgba(10, 15, 20, 0.3) 100%),
    radial-gradient(ellipse at center, 
      rgba(10, 15, 20, 0) 0%, 
      rgba(10, 15, 20, 0.15) 100%);
}

.section-content {
  position: relative;
  z-index: 10;
  width: 100%;
  max-width: 1200px;
}

/* Allow vertical scrolling when content overflows */
.section-content.scrollable {
  max-height: calc(100vh - 110px);
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

/* Hide scrollbar on desktop */
.section-content.scrollable::-webkit-scrollbar { display: none; }
.section-content.scrollable { 
  scrollbar-width: none; 
  -ms-overflow-style: none; 
}

.section-content h2 {
  margin-bottom: 1rem;
}

/* === HERO === */
.hero-layout {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
}

.hero-image {
  width: 450px;
  height: 365px;
  border-radius: 20px;
  overflow: hidden;
  flex-shrink: 0;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5);
}

.hero-image img { 
  width: 100%; 
  height: 100%; 
  object-fit: cover;
  object-position: center top;
}

.hero-text { 
  max-width: 550px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero-name {
  background: linear-gradient(135deg, var(--white), var(--cyan-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 1.25rem;
  white-space: nowrap;
}

.hero-tagline {
  font-size: 1.1rem;
  line-height: 1.75;
  color: var(--fog);
  text-align: left;
}

.scroll-hint {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 12px;
  color: rgba(248, 250, 252, 0.4);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  animation: fadeInOut 3s ease-in-out infinite;
}

.scroll-hint::after { content: '→'; font-size: 1.2rem; }

@keyframes fadeInOut {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 0.8; }
}

/* === APPROACH === */
.approach-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 3rem;
  margin-top: 2rem;
}

.approach-item {
  border-left: 2px solid rgba(6, 182, 212, 0.3);
  padding-left: 1.5rem;
}

.approach-item h3 { color: var(--white); margin-bottom: 0.75rem; }
.approach-item p { color: var(--fog); font-size: 0.95rem; line-height: 1.6; }

.section-subtitle {
  color: var(--fog);
  font-size: 0.95rem;
  margin-top: 0.5rem;
  margin-bottom: 1rem;
}

/* === JOURNEY === */
.journey-layout {
  display: grid;
  grid-template-columns: 1.5fr 0.5fr;
  gap: 2rem;
  align-items: start;
}

.timeline {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.timeline-item {
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.timeline-item:last-child { border-bottom: none; }

.timeline-header {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 1rem;
  cursor: pointer;
}

.timeline-year {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--cyan);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding-top: 0.2rem;
}

.timeline-summary h3 { 
  color: var(--white); 
  margin-bottom: 0.15rem; 
  font-size: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.expand-icon {
  display: inline-block;
  font-size: 0.85rem;
  color: rgba(6, 182, 212, 0.5);
  transition: transform 200ms ease, color 200ms ease;
}

.timeline-item.expanded .expand-icon {
  transform: rotate(90deg);
  color: var(--cyan);
}

.timeline-item:hover .expand-icon {
  color: var(--cyan);
}

.timeline-org { 
  font-size: 0.85rem; 
  color: rgba(6, 182, 212, 0.7); 
  margin-bottom: 0.25rem; 
}

.timeline-oneliner { 
  font-size: 0.85rem; 
  color: var(--fog); 
  line-height: 1.4;
}

.timeline-details {
  display: none;
  margin-top: 0.6rem;
  margin-left: 80px;
  padding-left: 1rem;
  border-left: 2px solid rgba(6, 182, 212, 0.2);
}

.timeline-item.expanded .timeline-details {
  display: block;
}

.timeline-details ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.timeline-details li {
  font-size: 0.85rem;
  color: var(--fog);
  line-height: 1.5;
  margin-bottom: 0.4rem;
  padding-left: 1rem;
  position: relative;
}

.timeline-details li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: rgba(6, 182, 212, 0.5);
}

.education-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.education-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: rgba(248, 250, 252, 0.4);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.education-item {
  padding-left: 1.25rem;
  border-left: 2px solid rgba(6, 182, 212, 0.3);
}

.education-degree { font-size: 1.4rem; font-weight: 800; color: var(--cyan); line-height: 1; }
.education-field { font-size: 0.9rem; font-weight: 600; color: var(--white); margin: 0.2rem 0; }
.education-school { font-size: 0.85rem; color: rgba(203, 213, 225, 0.6); line-height: 1.4; }

/* === WORK === */
.work-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
}

.featured-projects {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.featured-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: rgba(248, 250, 252, 0.4);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.featured-project {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.25rem;
  align-items: start;
}

.featured-image {
  width: 120px;
  height: 85px;
  border-radius: 10px;
  overflow: hidden;
  flex-shrink: 0;
}

.featured-image img { width: 100%; height: 100%; object-fit: cover; }

.featured-content h3 { color: var(--white); margin-bottom: 0.4rem; font-size: 1.1rem; }
.featured-content p { font-size: 0.9rem; color: var(--fog); line-height: 1.5; margin-bottom: 0.5rem; }

.featured-tags { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.featured-tag { font-size: 0.75rem; color: rgba(148, 163, 184, 0.8); font-weight: 600; }

/* Collapsible categories */
.project-categories {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.category-group {
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.category-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
  cursor: pointer;
  transition: color 300ms var(--flow);
}

.category-header:hover { color: var(--cyan); }

.category-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.category-toggle {
  font-size: 1.2rem;
  color: rgba(248, 250, 252, 0.4);
  transition: transform 300ms var(--flow), color 300ms var(--flow);
}

.category-group.open .category-toggle {
  transform: rotate(45deg);
  color: var(--cyan);
}

.category-projects {
  display: none;
  padding-bottom: 1rem;
}

.category-group.open .category-projects { display: block; }

.mini-project {
  padding: 0.6rem 0;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.mini-project h4 { font-size: 0.95rem; font-weight: 600; color: var(--white); margin-bottom: 0.2rem; }
.mini-project p { font-size: 0.85rem; color: var(--fog); line-height: 1.4; }

/* === CONNECT === */
.connect-layout {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.connect-text {
  font-size: 1.15rem;
  color: var(--fog);
  line-height: 1.8;
  margin-bottom: 3rem;
}

.connect-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2.5rem;
}

.connect-icon-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  color: var(--fog);
  transition: color 300ms var(--flow), transform 300ms var(--flow);
}

.connect-icon-link svg {
  width: 32px;
  height: 32px;
}

.connect-icon-link:hover {
  color: var(--cyan);
  transform: scale(1.1);
}

.connect-email {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--fog);
  transition: color 300ms var(--flow);
}

.connect-email svg {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.connect-email span {
  font-size: 1rem;
  font-weight: 500;
}

.connect-email:hover {
  color: var(--cyan);
}

/* === PROGRESS DOTS === */
.progress-dots {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 12px;
  z-index: 1000;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(248, 250, 252, 0.2);
  cursor: pointer;
  transition: all 300ms var(--flow);
}

.dot:hover { background: rgba(248, 250, 252, 0.4); }
.dot.active { background: var(--cyan); }

/* === MODAL === */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 15, 20, 0.9);
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 300ms var(--flow), visibility 300ms var(--flow);
}

.modal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.95);
  width: 90vw;
  max-width: 900px;
  max-height: 90vh;
  background: var(--slate);
  border-radius: 16px;
  z-index: 2001;
  opacity: 0;
  visibility: hidden;
  transition: opacity 300ms var(--flow), transform 300ms var(--flow), visibility 300ms var(--flow);
  display: flex;
  flex-direction: column;
}

body.modal-open .modal-backdrop {
  opacity: 1;
  visibility: visible;
}

body.modal-open .modal {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, -50%) scale(1);
}

.modal-header {
  display: flex;
  justify-content: flex-end;
  padding: 1rem 1.25rem 0;
}

.modal-close {
  background: none;
  border: none;
  color: var(--fog);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.5rem;
  line-height: 1;
  transition: color 200ms var(--flow);
}

.modal-close:hover { color: var(--white); }

.modal-content {
  padding: 0 2rem 2rem;
  overflow-y: auto;
  flex: 1;
  max-height: calc(90vh - 60px);
}

.modal-content::-webkit-scrollbar { width: 4px; }
.modal-content::-webkit-scrollbar-track { background: rgba(255,255,255,0.03); border-radius: 2px; }
.modal-content::-webkit-scrollbar-thumb { background: rgba(255, 255, 255, 0.15); border-radius: 2px; }

.modal-content h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--white);
}

.modal-text {
  color: var(--fog);
  line-height: 1.7;
  font-size: 0.95rem;
}

.modal-text p { margin-bottom: 1rem; }

/* Slideshow */
.modal-slideshow {
  margin-bottom: 1.5rem;
}

.slideshow-container {
  position: relative;
  border-radius: 12px;
  overflow: hidden;
  background: var(--deep);
}

.slide {
  display: none;
}

.slide.active {
  display: block;
}

.slide img {
  width: 100%;
  height: auto;
  max-height: 50vh;
  object-fit: contain;
}

.slideshow-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  margin-top: 1rem;
}

.slide-prev, .slide-next {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: var(--white);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1rem;
  transition: all 200ms var(--flow);
}

.slide-prev:hover, .slide-next:hover {
  background: var(--cyan);
  border-color: var(--cyan);
}

.slide-counter {
  color: var(--fog);
  font-size: 0.85rem;
}

/* Embedded documents */
.modal-embed {
  margin: 1.5rem 0;
  border-radius: 8px;
  overflow: hidden;
  background: var(--deep);
}

.modal-embed iframe {
  width: 100%;
  height: 450px;
  border: none;
  display: block;
}

.modal-embed-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: rgba(248, 250, 252, 0.5);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

/* Project links */
.project-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--cyan);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 0.5rem;
  transition: color 200ms var(--flow);
}

.project-link:hover { color: var(--cyan-light); }

.project-link::after {
  content: '→';
  font-size: 0.9rem;
}

.view-more {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: rgba(248, 250, 252, 0.5);
  cursor: pointer;
  margin-top: 0.4rem;
  transition: color 200ms var(--flow);
}

.view-more:hover { color: var(--cyan); }

/* === RESPONSIVE === */
@media (max-width: 1100px) {
  .approach-grid { grid-template-columns: repeat(2, 1fr); gap: 2rem; }
  .journey-layout { grid-template-columns: 1fr; gap: 1.5rem; }
  .work-layout { grid-template-columns: 1fr; gap: 2rem; }
  .education-list { 
    display: grid; 
    grid-template-columns: repeat(2, 1fr); 
    gap: 1rem; 
  }
  .education-label { grid-column: 1 / -1; }
}

@media (max-width: 768px) {
  /* Navigation */
  .nav-minimal { 
    gap: 0.5rem; 
    padding: 0.6rem 0.75rem;
    justify-content: center;
  }
  .nav-link { 
    font-size: 0.65rem; 
    padding: 0.35rem 0.5rem;
  }
  
  /* Sections - CRITICAL: top-align and allow scrolling on mobile */
  .section { 
    padding: 55px 4vw 20px;
    align-items: flex-start;
  }
  
  .section-content {
    max-height: calc(100vh - 75px);
    padding-top: 10px;
  }
  
  /* Make all section content scrollable on mobile */
  .section-content {
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }
  
  /* Hero */
  .hero-layout { 
    flex-direction: column; 
    text-align: center; 
    gap: 1.25rem; 
  }
  .hero-image { 
    width: 240px; 
    height: 195px; 
    order: -1;
  }
  .hero-tagline {
    font-size: 0.9rem;
    line-height: 1.6;
    text-align: center;
  }
  
  /* Approach */
  .approach-grid { 
    grid-template-columns: 1fr; 
    gap: 1rem; 
  }
  .approach-item {
    padding-left: 0.75rem;
  }
  .approach-item h3 {
    font-size: 0.9rem;
  }
  .approach-item p {
    font-size: 0.85rem;
  }
  
  /* Timeline / Journey */
  .journey-layout { 
    grid-template-columns: 1fr; 
    gap: 1.25rem; 
  }
  .timeline-header {
    grid-template-columns: 65px 1fr;
    gap: 0.6rem;
  }
  .timeline-year {
    font-size: 0.65rem;
  }
  .timeline-summary h3 {
    font-size: 0.9rem;
  }
  .timeline-org {
    font-size: 0.75rem;
  }
  .timeline-oneliner {
    font-size: 0.75rem;
  }
  .timeline-details {
    margin-left: 0;
    padding-left: 0.6rem;
    margin-top: 0.5rem;
  }
  .timeline-details li {
    font-size: 0.75rem;
  }
  
  /* Education */
  .education-list { 
    grid-template-columns: 1fr 1fr;
    gap: 0.6rem; 
  }
  .education-item {
    padding-left: 0.75rem;
  }
  .education-degree {
    font-size: 1.1rem;
  }
  .education-field {
    font-size: 0.85rem;
  }
  .education-school {
    font-size: 0.7rem;
  }
  
  /* Projects */
  .featured-project { 
    grid-template-columns: 1fr; 
  }
  .featured-image { 
    width: 100%; 
    height: 100px; 
  }
  .featured-content h3 {
    font-size: 0.9rem;
  }
  .featured-content p {
    font-size: 0.75rem;
  }
  .category-title {
    font-size: 0.75rem;
  }
  
  /* Connect */
  .connect-links { 
    flex-direction: row;
    flex-wrap: wrap;
    gap: 1.5rem;
    justify-content: center;
  }
  .connect-icon-link {
    width: 44px;
    height: 44px;
  }
  .connect-icon-link svg {
    width: 28px;
    height: 28px;
  }
  .connect-email {
    order: 1;
    width: 100%;
    justify-content: center;
  }
  .connect-email span {
    font-size: 0.9rem;
  }
  
  /* Modal */
  .modal {
    width: 95vw;
    max-height: 85vh;
  }
  .modal-header {
    padding: 0.75rem 1rem;
  }
  .modal-content {
    padding: 0 1rem 1rem;
  }
  .modal-embed iframe {
    height: 280px;
  }
  .slideshow-container img {
    max-height: 220px;
  }
}

@media (max-width: 480px) {
  /* Navigation */
  .nav-minimal { 
    gap: 0.35rem;
    padding: 0.5rem;
  }
  .nav-link { 
    font-size: 0.625rem; 
    letter-spacing: 0.03em;
    padding: 0.3rem 0.4rem;
  }
  
  /* Sections */
  .section {
    padding: 50px 3vw 15px;
  }
  
  .section-content {
    max-height: calc(100vh - 65px);
  }
  
  /* Typography */
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.3rem; }
  
  /* Hero */
  .hero-image { 
    width: 200px; 
    height: 162px; 
  }
  .hero-tagline {
    font-size: 0.85rem;
  }
  
  /* Timeline */
  .timeline-header {
    grid-template-columns: 55px 1fr;
    gap: 0.5rem;
  }
  .timeline-summary h3 {
    font-size: 0.85rem;
  }
  .timeline-org {
    font-size: 0.7rem;
  }
  .timeline-oneliner {
    font-size: 0.7rem;
  }
  
  /* Education */
  .education-list { 
    grid-template-columns: 1fr;
  }
  
  /* Projects */
  .featured-content h3 {
    font-size: 0.9rem;
  }
  
  /* Modal */
  .modal-embed iframe {
    height: 200px;
  }
}