/* =========================================================
   Georgios-Christoforos Kazlaris — academic personal site
   Design tokens
   ========================================================= */
:root {
  --paper: #f6f1e7;
  --paper-dim: #efe8d9;
  --ink: #211e1a;
  --ink-soft: #4a463f;
  --moss: #3f5d50;
  --moss-dark: #2c4238;
  --gold: #b9863b;
  --gold-soft: #e7c98f;
  --line: #dcd3be;
  --card-bg: #fffdf8;

  --font-display: "Fraunces", Georgia, serif;
  --font-body: "Source Sans 3", "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;

  --maxw: 1120px;
  --radius: 14px;
  --ease: cubic-bezier(0.22, 0.68, 0, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  display: block;
}
a {
  color: inherit;
  text-decoration: none;
}
ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.1;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--moss);
  display: flex;
  align-items: center;
  gap: 0.6em;
  margin-bottom: 0.9em;
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--gold);
  display: inline-block;
}

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 32px;
}

/* focus visibility */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--moss);
  outline-offset: 3px;
  border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* =========================================================
   Header / nav
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(246, 241, 231, 0.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--ink);
}
.brand .mono {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--moss);
  color: var(--paper);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0;
}
.brand-name {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.brand-name strong {
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.92rem;
}
.brand-name span {
  font-size: 0.72rem;
  color: var(--ink-soft);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 34px;
}
.main-nav a {
  position: relative;
  font-size: 0.94rem;
  padding: 6px 0;
  color: var(--ink-soft);
  transition: color 0.25s var(--ease);
}
.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 0;
  height: 2px;
  background: var(--gold);
  transition: right 0.3s var(--ease);
}
.main-nav a:hover,
.main-nav a.active {
  color: var(--ink);
}
.main-nav a:hover::after,
.main-nav a.active::after {
  right: 0;
}

.lang-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 4px;
  background: var(--card-bg);
}
.lang-toggle button {
  background: none;
  border: none;
  cursor: pointer;
  padding: 5px 12px;
  border-radius: 16px;
  color: var(--ink-soft);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  transition:
    background 0.2s var(--ease),
    color 0.2s var(--ease);
}
.lang-toggle button.is-active {
  background: var(--moss);
  color: var(--paper);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--ink);
  margin: 5px 0;
  transition: 0.3s;
}

/* =========================================================
   Hero
   ========================================================= */
.hero {
  padding: 96px 0 80px;
  overflow: hidden;
}
.hero .wrap {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}
.hero-name {
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  margin-bottom: 0.28em;
}
.hero-name .accent {
  color: var(--moss);
  font-style: italic;
}
.hero-title {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--ink-soft);
  margin-bottom: 1.4em;
}
.hero-tagline {
  font-size: 1.12rem;
  max-width: 46ch;
  color: var(--ink-soft);
  margin-bottom: 2em;
}
.btn-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: 30px;
  font-size: 0.94rem;
  font-weight: 600;
  transition:
    transform 0.25s var(--ease),
    box-shadow 0.25s var(--ease),
    background 0.25s var(--ease);
  border: 1px solid transparent;
}
.btn-primary {
  background: var(--moss);
  color: var(--paper);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px -10px rgba(63, 93, 80, 0.55);
  background: var(--moss-dark);
}
.btn-ghost {
  border-color: var(--line);
  color: var(--ink);
  background: var(--card-bg);
}
.btn-ghost:hover {
  transform: translateY(-2px);
  border-color: var(--gold);
}

/* signature element: layered AR card stack */
.card-stack-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 22px;
}
.card-stack {
  position: relative;
  height: 340px;
  width: 100%;
  perspective: 1200px;
}
.card-stack .stack-card {
  position: absolute;
  width: 64%;
  height: 180px;
  top: 50%;
  left: 50%;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 18px 40px -20px rgba(33, 30, 26, 0.25);
  padding: 22px 24px;
  cursor: pointer;
  transition:
    transform 0.5s var(--ease),
    opacity 0.5s var(--ease),
    box-shadow 0.5s var(--ease);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.stack-card .tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--moss);
}
.stack-card h4 {
  font-size: 1.05rem;
  margin: 0.4em 0 0;
}
.stack-card .corner {
  position: absolute;
  width: 14px;
  height: 14px;
  border: 2px solid var(--gold);
  opacity: 0.85;
}
.stack-card .corner.tl {
  top: 10px;
  left: 10px;
  border-right: none;
  border-bottom: none;
}
.stack-card .corner.br {
  bottom: 10px;
  right: 10px;
  border-left: none;
  border-top: none;
}

/* carousel positions — .pos-0 is front/active, .pos-1 and .pos-2 stack behind */
.stack-card.pos-0 {
  transform: translate(-50%, -50%) rotate(0deg) scale(1);
  z-index: 3;
  opacity: 1;
  box-shadow: 0 22px 46px -18px rgba(33, 30, 26, 0.32);
}
.stack-card.pos-1 {
  transform: translate(-50%, -50%) translate(78px, 26px) rotate(7deg)
    scale(0.92);
  z-index: 2;
  opacity: 0.8;
}
.stack-card.pos-2 {
  transform: translate(-50%, -50%) translate(-78px, 42px) rotate(-7deg)
    scale(0.86);
  z-index: 1;
  opacity: 0.6;
}

.stack-nav {
  display: flex;
  align-items: center;
  gap: 18px;
}
.stack-nav button {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: var(--card-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--ink);
  transition:
    background 0.25s var(--ease),
    color 0.25s var(--ease),
    border-color 0.25s var(--ease),
    transform 0.25s var(--ease);
}
.stack-nav button:hover {
  background: var(--moss);
  color: var(--paper);
  border-color: var(--moss);
  transform: translateY(-2px);
}
.stack-nav button svg {
  width: 18px;
  height: 18px;
}
.stack-dots {
  display: flex;
  gap: 8px;
}
.stack-dots span {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--line);
  transition:
    background 0.25s var(--ease),
    transform 0.25s var(--ease);
}
.stack-dots span.is-active {
  background: var(--gold);
  transform: scale(1.2);
}

/* =========================================================
   Sections / reveal
   ========================================================= */
section {
  padding: 88px 0;
}
.section-alt {
  background: var(--paper-dim);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 0.7s var(--ease),
    transform 0.7s var(--ease);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

.section-head {
  max-width: 640px;
  margin-bottom: 52px;
}
.section-head h2 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
}
.section-head p {
  color: var(--ink-soft);
  font-size: 1.05rem;
}

/* about */
.about-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 56px;
  align-items: start;
}
.avatar-placeholder {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: linear-gradient(155deg, var(--moss), var(--moss-dark));
  color: var(--paper);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 600;
  border: 6px solid var(--card-bg);
  box-shadow: 0 16px 32px -16px rgba(33, 30, 26, 0.4);
  position: relative;
}
.avatar-placeholder::after {
  content: "replace photo";
  position: absolute;
  bottom: -14px;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.08em;
  background: var(--gold);
  color: var(--ink);
  padding: 3px 10px;
  border-radius: 10px;
  white-space: nowrap;
  text-transform: uppercase;
}
.about-body p {
  margin: 0 0 1.1em;
  color: var(--ink-soft);
  text-align: justify;
  text-justify: inter-word;
}
.about-body strong {
  color: var(--ink);
}

/* highlight cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.hl-card {
  display: flex;
  flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  transition:
    transform 0.3s var(--ease),
    box-shadow 0.3s var(--ease),
    border-color 0.3s var(--ease);
}
.hl-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px -22px rgba(33, 30, 26, 0.3);
  border-color: var(--gold);
}
.hl-card .num {
  font-family: var(--font-mono);
  color: var(--gold);
  font-size: 0.85rem;
  margin-bottom: 0.6em;
  display: block;
}
.hl-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.4em;
}
.hl-card p {
  color: var(--ink-soft);
  font-size: 0.95rem;
  margin: 0;
  flex-grow: 1;
}
.hl-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--moss);
  font-weight: 600;
}
.hl-link svg {
  width: 14px;
  height: 14px;
  transition: transform 0.25s var(--ease);
}
.hl-card:hover .hl-link svg {
  transform: translate(3px, -3px);
}

/* timeline */
.timeline {
  position: relative;
  margin-left: 8px;
  padding-left: 34px;
  border-left: 2px solid var(--line);
  max-height: 560px;
  overflow-y: auto;
  padding-right: 18px;
  scrollbar-width: thin;
  scrollbar-color: var(--gold) transparent;
  /* fade hint at the bottom to show there's more to scroll */
  mask-image: linear-gradient(
    to bottom,
    #000 calc(100% - 28px),
    transparent 100%
  );
  -webkit-mask-image: linear-gradient(
    to bottom,
    #000 calc(100% - 28px),
    transparent 100%
  );
}
.timeline::-webkit-scrollbar {
  width: 6px;
}
.timeline::-webkit-scrollbar-track {
  background: transparent;
}
.timeline::-webkit-scrollbar-thumb {
  background: var(--gold-soft);
  border-radius: 10px;
}
.timeline::-webkit-scrollbar-thumb:hover {
  background: var(--gold);
}
.tl-item {
  position: relative;
  padding-bottom: 40px;
}
.tl-item:last-child {
  padding-bottom: 4px;
}
.tl-item::before {
  content: "";
  position: absolute;
  left: -42px;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--paper);
  border: 3px solid var(--moss);
}
.tl-date {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--moss);
  letter-spacing: 0.06em;
}
.tl-item h3 {
  font-size: 1.12rem;
  margin: 0.3em 0 0.3em;
}
.tl-item p {
  color: var(--ink-soft);
  margin: 0;
  font-size: 0.96rem;
}

/* publications */
.pub-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.pub-item {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 26px;
  display: flex;
  gap: 20px;
  align-items: flex-start;
  transition:
    border-color 0.3s var(--ease),
    transform 0.3s var(--ease);
}
.pub-item:hover {
  border-color: var(--gold);
  transform: translateX(4px);
}
.pub-year {
  font-family: var(--font-mono);
  color: var(--moss);
  font-weight: 700;
  min-width: 52px;
}
.pub-body h3 {
  font-size: 1.05rem;
  margin: 0 0 0.35em;
}
.pub-body .venue {
  font-size: 0.9rem;
  color: var(--ink-soft);
  font-style: italic;
}
.pub-body .authors {
  font-size: 0.86rem;
  color: var(--ink-soft);
  margin-top: 0.35em;
}

/* tags */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.tag-pill {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 7px 16px;
  background: var(--card-bg);
  color: var(--ink-soft);
}

/* CV page */
.cv-block {
  margin-bottom: 56px;
}
.cv-block h2 {
  font-size: 1.5rem;
  border-bottom: 2px solid var(--line);
  padding-bottom: 12px;
  margin-bottom: 24px;
}
.cv-entry {
  display: grid;
  grid-template-columns: 170px 1fr;
  gap: 20px;
  margin-bottom: 26px;
}
.cv-entry .when {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--moss);
}
.cv-entry h3 {
  font-size: 1.05rem;
  margin: 0 0 0.3em;
}
.cv-entry h3 a {
  color: inherit;
  border-bottom: 1px dotted var(--gold);
  transition: color 0.2s var(--ease);
}
.cv-entry h3 a:hover {
  color: var(--moss);
}
.cv-entry p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.95rem;
}
.skill-groups {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.skill-groups h4 {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--gold);
  margin-bottom: 12px;
}

/* contact */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
}
.contact-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.contact-list-solo {
  max-width: 520px;
  margin: 0 auto;
}

.extra-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: center;
  max-width: 720px;
  margin: 0 auto 44px;
}
.extra-links a {
  flex: 1 1 260px;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 20px 22px;
  border-radius: var(--radius);
  background: var(--moss);
  color: var(--paper);
  transition:
    transform 0.25s var(--ease),
    box-shadow 0.25s var(--ease),
    background 0.25s var(--ease);
}
.extra-links a:hover {
  transform: translateY(-4px);
  box-shadow: 0 18px 36px -16px rgba(63, 93, 80, 0.5);
  background: var(--moss-dark);
}
.extra-links a strong {
  display: block;
  font-size: 0.98rem;
}
.extra-links .ic2 {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  flex-shrink: 0;
  background: rgba(255, 255, 255, 0.16);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
}
.extra-links-sub {
  font-size: 0.82rem;
  color: var(--gold-soft);
  margin-top: 2px;
}
.contact-list a {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card-bg);
  transition:
    transform 0.25s var(--ease),
    border-color 0.25s var(--ease);
}
.contact-list a:hover {
  transform: translateX(6px);
  border-color: var(--gold);
}
.contact-list .ic {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--moss);
  color: var(--paper);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  flex-shrink: 0;
}
form.contact-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.contact-form label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
  margin-bottom: 6px;
  display: block;
}
.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 13px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 0.96rem;
  background: var(--card-bg);
  color: var(--ink);
}
.contact-form textarea {
  min-height: 140px;
  resize: vertical;
}

/* footer */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 40px 0;
  margin-top: 40px;
}
.site-footer .wrap {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}
.footer-note {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
}
.footer-links {
  display: flex;
  gap: 20px;
}
.footer-links a {
  font-size: 0.85rem;
  color: var(--ink-soft);
  transition: color 0.2s var(--ease);
}
.footer-links a:hover {
  color: var(--moss);
}

/* page hero (inner pages) */
.page-hero {
  padding: 64px 0 20px;
}
.page-hero h1 {
  font-size: clamp(2rem, 4vw, 2.8rem);
}
.page-hero p {
  color: var(--ink-soft);
  max-width: 60ch;
  font-size: 1.05rem;
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 900px) {
  .hero .wrap {
    grid-template-columns: 1fr;
  }
  .card-stack {
    height: 300px;
    margin-top: 20px;
  }
  .card-stack .stack-card {
    width: 78%;
    height: 160px;
    padding: 18px 20px;
  }
  .stack-card.pos-1 {
    transform: translate(-50%, -50%) translate(46px, 20px) rotate(6deg)
      scale(0.92);
  }
  .stack-card.pos-2 {
    transform: translate(-50%, -50%) translate(-46px, 32px) rotate(-6deg)
      scale(0.86);
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .card-grid {
    grid-template-columns: 1fr 1fr;
  }
  .skill-groups {
    grid-template-columns: 1fr 1fr;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  .main-nav {
    position: fixed;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 8px 32px 20px;
    transform: translateY(-130%);
    opacity: 0;
    transition:
      transform 0.35s var(--ease),
      opacity 0.35s var(--ease);
  }
  .main-nav.is-open {
    transform: translateY(0);
    opacity: 1;
  }
  .main-nav a {
    padding: 12px 0;
    width: 100%;
    border-bottom: 1px solid var(--line);
  }
  .nav-toggle {
    display: block;
  }
  .card-grid {
    grid-template-columns: 1fr;
  }
  .skill-groups {
    grid-template-columns: 1fr;
  }
  .cv-entry {
    grid-template-columns: 1fr;
    gap: 6px;
  }
  .wrap {
    padding: 0 20px;
  }
  .timeline {
    max-height: 460px;
  }
}