/* style.css */
/* ========== Core Colours & Vars ========== */
/* Test comment */
:root {
  --background: #1e1e1e;
  --white: #ffffff;
  --panel: #2c2c2c;
  --panel-grad: #363636;
  --txt-dark: #111;
  --radius: 16px;
  --shadow: 0 8px 24px rgba(0,0,0,.15);
  --tr: .45s cubic-bezier(.25,.8,.25,1);
  --card-h: 420px;
  --header-h: 84px;
}
@media(max-width:600px) {
  :root { --header-h: 54px; }
}

/* ===== Base ===== */
html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
}
body {
  margin: 0;
  font-family: Poppins, sans-serif;
  background: var(--background);
  color: #eaeaea;
  overflow-x: hidden;
}
ul { margin: 0; padding: 0; list-style: none; }

/* ===== Header ===== */
.site-header {
  position: fixed; top: 0; width: 100%; z-index: 300;
  background: rgba(30,30,30,.35); backdrop-filter: blur(10px);
}
.nav-container {
  max-width: 92%; margin: 0 auto; padding: 1.6rem 0; display: flex;
}
.nav-links {
  display: flex; width: 100%; justify-content: space-between;
}
.nav-links a { font-weight: 600; color: #fff; transition: opacity .25s; }
.nav-links a:hover { opacity: .7; }

/* ===== Hero ===== */
.hero {
  position: relative; display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  min-height: 85vh; padding-top: var(--header-h); padding-bottom: 3rem;
  overflow: hidden;
}

.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(rgba(0,0,0,.15),rgba(0,0,0,0)),
              url(images/background.png) center/cover no-repeat;
  pointer-events: none;
}
.hero-inner {
  position: relative; z-index: 1; width: 100%; max-width: 900px;
  margin: 0 auto; padding: 0 1rem; display: flex;
  flex-direction: column; align-items: center;
}
.hero h1 {
  font-family: 'Poppins', sans-serif;
  font-size: clamp(2.2rem,7vw,4.5rem);
  font-weight: 800;
  color: #fff;
  margin: 2rem 0 1.2rem;
  text-align: center;
  letter-spacing: -0.03em;
}
.tagline {
  font-family: 'Poppins', sans-serif;
  font-size: 2rem;
  font-weight: 700;
  color: #ededed;
  margin: 1.2rem 0 1.5rem;
  text-align: center;
  max-width: 100vw;         /* Allow to span full viewport width */
  margin-left: calc(50% - 50vw); /* Center and break out of container */
  margin-right: calc(50% - 50vw);
  padding: 0 2rem;
  box-sizing: border-box;
  letter-spacing: 0.01em;
  display: block;
  position: relative;
  left: 0;
  transform: none;
  z-index: 1;
}
.subtitle {
  font-family: 'Poppins', sans-serif;
  font-size: 1.2rem;
  font-weight: 500;
  margin: 1rem 0 2rem;
  text-align: center;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .3rem;
  color: #ededed;
  letter-spacing: 0.01em;
}
.pipe {
  font-weight: bold;
  padding: 0 0.4em; /* adjust horizontal spacing here */
}


.subtitle span { display: inline; }

/* About me */
.hero-about {
  margin-top: 2rem;
  background: rgba(255,255,255,.5);
  padding: 1.5rem;
  border-radius: 38px;
  display: inline-block;
  max-width: 100%;
  margin-left: auto;
  margin-right: auto;
  box-shadow: 0 2px 12px rgba(0,0,0,.08);
  color: #111;
  backdrop-filter: blur(4px);
  font-family: 'Poppins', sans-serif;
}
.hero-about .section-title,
.hero-about p {
  color: #111;
  font-family: 'Poppins', sans-serif;
}
.hero-about p {
  max-width: 850px;
  margin: 0 auto 1.2rem;
  text-align: center;
  font-size: 1.2rem;
  line-height: 1.6;
  font-weight: 400;
  letter-spacing: 0.01em;
}
.hero-about .view-projects-link {
  color: #111; text-decoration: underline; font-weight: 700; font-size: 1.15rem;
}

/* ===== Chevron ===== */
@keyframes bounce {
  0%,20%,50%,80%,100% { transform: translateY(0); }
  40% { transform: translateY(6px); }
  60% { transform: translateY(3px); }
}
.scroll-down {
  margin: 2rem auto 0; animation: bounce 2s infinite;
}
.scroll-down svg { stroke: #fff; }

/* ===== Content-box ===== */
.content-box {
  max-width: 1200px;
  margin: 2.5rem auto 3rem;
  padding: 2.5rem 1rem;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ===== Sections ===== */
.section { 
  padding: 1.5rem 1rem; 
}
.section-light { background: var(--white); }
.books-panel {
  background: linear-gradient(180deg, var(--panel) 0%, var(--panel-grad) 100%);
  padding: 2.5rem 1rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  max-width: 1200px;
  margin: 0 auto 3rem;
}
.section-title {
  font-size: 2.4rem; font-weight: 700; text-align: center;
  margin-bottom: 1rem; color: var(--txt-dark);
}
.books-panel .section-title { color: #fff; }
.section-text { text-align: center; font-size: 1.2rem; margin-bottom: 1.8rem; color: #555; }

/* ===== Tabs ===== */
.tab-nav {
  display: flex; justify-content: center; gap: .6rem;
  flex-wrap: wrap; margin-bottom: .8rem;
}
.tab-nav li {
  padding: .4rem 1rem; border-radius: 8px; font-weight: 600;
  font-size: .85rem; cursor: pointer; background: #dcdcdc;
  color: #333; transition: var(--tr);
}
.tab-nav li.active { background: #374957; color: #fff; }

/* ===== Sub-menu ===== */
.sub-nav-wrapper {
  margin-bottom: 1.4rem;
  min-height: 3rem;
}
.sub-nav {
  display: flex;
  justify-content: center;
  gap: .6rem;
  flex-wrap: wrap;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  width: fit-content;
  margin: 0 auto;
  max-width: 100%;
}
.sub-nav.open {
  max-height: none;
  opacity: 1;
  visibility: visible;
  margin-bottom: 1rem;
}
.sub-nav li {
  padding: .4rem 1rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: .85rem;
  cursor: pointer;
  background: #dcdcdc;
  color: #333;
  transition: var(--tr);
  white-space: nowrap;
  flex-shrink: 0;
  width: fit-content;
}
.sub-nav li.active {
  background: #374957;
  color: #fff;
}

/* ===== Panels ===== */
.tab-panel { display: none; }
.tab-panel.active { display: block; }
.sub-section-text {
  text-align: center; font-size: 1.15rem; margin: .4rem auto 2rem;
  max-width: 800px; color: #555;
}

/* ===== Projects grid ===== */
.projects-grid {
  display: flex; flex-wrap: wrap; gap: 2rem; justify-content: center;
}
@media(max-width:900px) { .projects-grid { gap: 1.6rem; } }
@media(max-width:600px) {
  .projects-grid { flex-direction: column; align-items: center; }
}

/* ===== Cards ===== */
.card {
  display: flex;
  flex-direction: column;
  width: 300px;
  max-width: 90vw;
  height: var(--card-h);
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 2px 6px rgba(0,0,0,.1);
  transition: .35s;
  flex-shrink: 0;
}
.card:hover {
  transform: translateY(-6px) scale(1.03);
  box-shadow: 0 10px 26px rgba(0,0,0,.25);
}
.card img { width: 100%; height: 180px; object-fit: cover; }
.card-body {
  flex: 1 1 auto; display: flex; flex-direction: column; padding: 1rem;
}
.card h3 {
  font-size: 1.1rem; font-weight: 600; margin-bottom: .4rem;
  color: var(--txt-dark);
}
.card p { font-size: 0.95rem; margin-bottom: .8rem; color: #444; }
.card-links { margin-top: auto; }
.card-links a {
  display: inline-block; background: #374957; color: #fff;
  padding: .45rem .9rem; border-radius: var(--radius);
  font-size: .8rem; margin-right: .5rem; transition: .25s;
}
.card-links a:hover { transform: scale(1.05); opacity: .85; }
.placeholder-card {
  justify-content: center; align-items: center; text-align: center;
  height: var(--card-h);
}
.placeholder-card .card-links { visibility: hidden; }

/* ===== Tool-stack ===== */
.stack-title {
  text-align: center; font-size: 1.2rem; font-weight: 600;
  margin: 2.2rem 0 .7rem; color: var(--txt-dark);
}
.stack-list {
  display: flex; flex-wrap: wrap; gap: .55rem; justify-content: center;
}
.stack-list li {
  background: #f0f0f0; /* lighter background for better readability */
  padding: .5rem 1rem; /* slightly larger padding */
  border-radius: 20px; /* more rounded oval shape */
  font-size: 0.85rem; /* slightly larger font size */
  font-weight: 600; 
  color: #222; /* darker text for better contrast */
  transition: background-color 0.3s ease, color 0.3s ease;
}
.stack-list li:hover {
  background-color: #dcdcdc; /* subtle hover effect */
  color: #000;
}

.diamond-divider {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin: 1.5rem 0;
}
.diamond {
  width: 20px;
  height: 20px;
  background-color: #999;
  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
  opacity: 0.6;
  transition: opacity 0.3s ease;
}
.diamond:hover {
  opacity: 0.6;
  background-color: #999;
}
/* ===== Books ===== */
.books-grid {
  display: grid;
  gap: 1.6rem;
  justify-items: center;
  grid-template-columns: repeat(auto-fit,minmax(120px,1fr));
  width: 100%;
}
.book-card {
  text-align: center;
  width: 100%;
  max-width: 160px;
}
.book-card img {
  width: 100%;
  max-width: 140px;
  height: auto;
  aspect-ratio: 7/10;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 2px 6px rgba(0,0,0,.15);
}
.book-card span {
  display: block;
  margin-top: 1rem;
  font-size: .9rem;
  font-weight: 600;
  color: #fff;
  text-align: center;
}
#books .section-text {
  color: #ddd;
  margin-bottom: 2rem;
  font-size: 1.2rem;
}

/* ===== Footer ===== */
.site-footer {
  text-align: center; padding: 1rem 0 2rem; font-size: .9rem; color: #999;
}

.section-divider {
  margin-top: 2rem;
  margin-bottom: 1.5rem;
  border: none;
  border-top: 1px solid #ccc;
}

/* ===== Hamburger & Mobile tweaks ===== */
.nav-toggle {
  display: none; flex-direction: column; justify-content: center;
  align-items: center; width: 38px; height: 38px; background: none;
  border: none; cursor: pointer; z-index: 400; margin-right: 1rem;
}
.nav-toggle span {
  display: block; width: 26px; height: 3px; margin: 4px 0;
  background: #fff; border-radius: 2px; transition: .3s;
}
.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}
.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media(max-width:600px) {
  .nav-container { padding: 1rem 1rem; justify-content: center; max-width: 100%; }
  .nav-links {
    flex-direction: column; gap: .2rem; align-items: center;
    width: 100%; padding: .5rem 0; background: rgba(30,30,30,.95);
    position: absolute; top: var(--header-h); left: 0; right: 0; display: none;
  }
  .nav-links.show { display: flex; }
  .nav-links a { padding: .4rem; width: 100%; text-align: center; }

  .hero { padding-top: var(--header-h); padding-left: 1rem; padding-right: 1rem; }
  .hero-inner { padding: 0; }
  .hero h1 { font-size: clamp(2rem,8vw,3rem); margin: 1.2rem 0 1rem; }
  .tagline { font-size: 1.1rem; margin: 1rem 0; padding: 0 .2rem; }
  .subtitle { font-size: 1.1rem; margin: 1.2rem 0; flex-direction: column; gap: 0; }
  .pipe { display: none; }
  .scroll-down svg { width: 46px; height: 46px; }
  .nav-toggle { display: flex; }

  .sub-nav {
    flex-direction: column;
    align-items: center;
    gap: .4rem;
    width: 100%;
  }
  .sub-nav li {
    width: fit-content;
    min-width: auto;
    text-align: center;
  }
  .sub-nav.open {
    margin-bottom: 1.5rem;
  }

  .projects-grid { flex-direction: column; align-items: center; }

  .card {
    width: 280px;
  }
}

@media(max-width:400px) {
  .card {
    width: 260px;
  }
  .projects-grid { gap: 1rem; }
  .books-grid { grid-template-columns: 1fr; gap: 1rem; }
  .book-card img { max-width: 90vw; }
}

/* ===== Books Carousel ===== */
.carousel-container {
  position: relative;
  width: calc(100% - 4rem);
  max-width: 1200px;
  margin: 0 auto;
  padding: 0;
  overflow: hidden;
  background: var(--white);
  border-radius: 16px;
  border: none;
  /* softer outer shadow + subtle inset highlight */
  box-shadow:
    0 8px 24px rgba(0, 0, 0, 0.20),
    inset 0 1px 1px rgba(255, 255, 255, 0.1);
  z-index: 0;
}

/* gradient "curtains" to cover the white curves and fade into charcoal */
.carousel-container::before,
.carousel-container::after {
  content: "";
  position: absolute;
  top: 0; bottom: 0;
  pointer-events: none;
  z-index: 2;           /* above the books but under buttons */
}

/* left fade */
.carousel-container::before {
  left: -300px;          /* extend well beyond edge */
  width: 600px;
  background: linear-gradient(
    to right,
    var(--panel)    0%,   /* full charcoal */
    var(--panel)   30%,   /* hold color in */
    rgba(44,44,44,0.7) 60%,/* begin soft fade */
    transparent    100%   /* clear by the end */
  );
}

/* right fade */
.carousel-container::after {
  right: -300px;
  width: 600px;
  background: linear-gradient(
    to left,
    var(--panel)    0%,
    var(--panel)   30%,
    rgba(44,44,44,0.7) 60%,
    transparent    100%
  );
}

.carousel {
  position: relative;
  width: 100%;
  overflow: hidden;
  padding: 0 1rem;
  z-index: 1;           /* below the fades */
}

.carousel-track {
  display: flex;
  gap: 2rem;
  padding: 1rem 0;
  will-change: transform;
  width: fit-content;
  margin: 0 auto;
}

.book-card {
  flex: 0 0 300px;
  text-align: center;
  transition: all 0.3s ease;
  position: relative;
  opacity: 0.8;
  transform: scale(0.95);
  margin: 0;
}

.book-card:hover,
.book-card.active {
  opacity: 1;
  transform: scale(1.05);
  z-index: 3;           /* above the track */
}

.book-card img {
  width: 100%;
  height: auto;
  aspect-ratio: 7/10;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
  transition: transform 0.3s ease;
}

.book-card:hover img,
.book-card.active img {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(0,0,0,0.25);
}

/* remove underline on the linked title */
.carousel .book-card a {
  text-decoration: none;
}

.book-card span {
  display: block;
  margin-top: 1rem;
  font-size: .9rem;
  font-weight: 600;
  color: #000;
  text-align: center;
  transition: color 0.3s ease;
  padding: 0 1rem;
}

.book-card:hover span,
.book-card.active span {
  color: #000;
  text-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

.carousel-button {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255, 255, 255, 0.1);
  border: none;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.3s ease;
  z-index: 4;
  backdrop-filter: blur(5px);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.carousel-button:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-50%) scale(1.1);
  border-color: rgba(255, 255, 255, 0.2);
}

.carousel-button.prev {
  left: 1rem;
}

.carousel-button.next {
  right: 1rem;
}

.carousel-button svg {
  stroke: #fff;
  width: 24px;
  height: 24px;
}

@media(max-width:900px) {
  .book-card {
    flex: 0 0 250px;
  }
  .carousel-container::before,
  .carousel-container::after {
    left: -150px; right: -150px;
    width: 300px;
  }
}

@media(max-width:600px) {
  .carousel {
    padding: 0 0.5rem;
  }
  .carousel-button {
    width: 32px;
    height: 32px;
  }
  .carousel-button svg {
    width: 20px;
    height: 20px;
  }
  .book-card {
    flex: 0 0 200px;
  }
  .carousel-container::before,
  .carousel-container::after {
    left: -100px; right: -100px;
    width: 200px;
  }
  .carousel-button.prev {
    left: 0.5rem;
  }
  .carousel-button.next {
    right: 0.5rem;
  }
}

/* Responsive tweaks */
@media(max-width:950px) {
  .hero-inner {
    max-width: 100% !important;
    padding-left: 1rem !important;
    padding-right: 1rem !important;
    box-sizing: border-box;
  }
  .hero {
    padding-left: 1rem !important;
    padding-right: 1rem !important;
    box-sizing: border-box;
  }
  .hero-about {
    box-sizing: border-box;
  }
  .tagline {
    margin-left: 0 !important;
    margin-right: 0 !important;
    padding-left: 1rem !important;
    padding-right: 1rem !important;
    box-sizing: border-box;
  }
}
@media(max-width:900px) {
  .book-card {
    flex: 0 0 250px;
  }
  .carousel-container::before,
  .carousel-container::after {
    width: 150px;
  }
}

@media(max-width:600px) {
  .carousel {
    padding: 0 0.5rem;
  }
  .carousel-button {
    width: 32px;
    height: 32px;
  }
  .carousel-button svg {
    width: 20px;
    height: 20px;
  }
  .book-card {
    flex: 0 0 200px;
  }
  .carousel-container::before,
  .carousel-container::after {
    width: 100px;
  }
  .carousel-button.prev {
    left: 0.5rem;
  }
  .carousel-button.next {
    right: 0.5rem;
  }
}
/* Responsive tweak for extra-large screens */
@media (min-width: 1400px) {
  .tagline {
    max-width: 1200px;
    font-size: 2.3rem;
  }
}

/* Responsive tweaks for mobile */
@media (max-width: 700px) {
  .tagline {
    font-size: 1.2rem;
    padding: 0 1rem;
    max-width: 100vw;
    margin-left: calc(50% - 50vw);
    margin-right: calc(50% - 50vw);
    word-break: break-word;
  }
}

.lottie-background {
  display: flex;
  justify-content: center;
  margin-top: -140px;
  margin-bottom: -100px;
  opacity: 0.2; /* Make Lottie animation semi-transparent */
}

.about-fade {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 1s cubic-bezier(.25,.8,.25,1), transform 1s cubic-bezier(.25,.8,.25,1);
}

.about-fade.visible {
  opacity: 1;
  transform: none;
}


/* — Video thumbnail + play button — */
.video-thumb {
  position: relative;
  width: 100%;
  overflow: hidden; /* keep thumbnail clipped */
  cursor: pointer;
}

.video-thumb img {
  display: block;
  width: 100%;
}

/* — Video thumbnail + play button — */
.video-thumb .play-overlay {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 40px;
  height: 40px;
  transform: translate(-50%, -50%) scale(1);
  background: url('images/play-icon.svg') no-repeat center/contain;
  opacity: 0.1; /* start very faint */
  pointer-events: none;
  z-index: 2;
  /* animate both size and opacity */
  transition: transform 0.2s ease-in-out, opacity 0.2s ease-in-out;
}

/* On hover of the whole card, bump opacity and (optionally) scale */
.video-card:hover .play-overlay {
  opacity: 1;                 /* fade in fully */
  transform: translate(-50%, -50%) scale(1.1);  /* grow slightly */
}

/* ——— Nav-link icons ——— */
.icon {
  width: 1.4em;               /* increase size */
  height: 1.4em;
  margin-right: 0.5em;
  vertical-align: middle;
  vector-effect: non-scaling-stroke;
}
/* Nav-links: no underline & larger text */
.nav-links a {
  text-decoration: none;
  font-size: 1.2rem;   /* adjust this value as needed */
}

.nav-links a:hover {
  text-decoration: none;
}


#projects {
  padding-top: 0.8rem;
}

.hero-about a.view-projects-link {
  text-decoration: underline;
  color: #003366;
  cursor: pointer;
  position: relative;
  z-index: 10;
}

#view-ai-assistant-link {
  text-decoration: underline;
  color: #003366;
  cursor: pointer;
  position: relative;
  z-index: 10;
}

.section-title {
  margin-top: 0.4rem;
}