/* ============================================
   Prof. Dr. V. Yavuz Tokgöz — Site Stilleri
   ============================================ */

:root {
  --navy: #0B1E3D;
  --navy-deep: #071528;
  --ink: #212936;
  --ink-soft: #4B5563;
  --paper: #FAFAF8;
  --paper-alt: #F1EEE8;
  --line: #E4E1DA;
  --accent: #A9824C;
  --accent-soft: #EFE6D4;
  --radius: 2px;
  --max: 46rem;
  --max-wide: 68rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    /* Site is intentionally light-only for a clinical, print-like feel;
       kept legible if a viewer forces dark UI chrome around it. */
  }
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 18.5px;
  line-height: 1.68;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: "Newsreader", Georgia, serif;
  color: var(--navy);
  font-weight: 500;
  line-height: 1.2;
  margin: 0 0 0.5em;
}

h1 { font-size: clamp(2.2rem, 5.4vw, 3.2rem); font-weight: 400; }
h2 { font-size: clamp(1.65rem, 3.4vw, 2.05rem); }
h3 { font-size: 1.3rem; font-weight: 600; font-family: "Inter", sans-serif; color: var(--navy); }

p { margin: 0 0 1.1em; color: var(--ink-soft); max-width: 62ch; }

a { color: var(--navy); }
a.plain { color: inherit; text-decoration: none; }

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

.container {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.prose {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---------- Header / Nav ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(250, 250, 248, 0.92);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 124px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  text-decoration: none;
}

.brand img {
  height: 82px;
  width: 82px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
}

.brand-text {
  font-family: "Newsreader", serif;
  font-size: 1.78rem;
  color: var(--navy);
  line-height: 1.2;
  white-space: nowrap;
}

.brand-text small {
  display: block;
  font-family: "Inter", sans-serif;
  font-size: 0.96rem;
  letter-spacing: 0.01em;
  color: var(--ink-soft);
  font-weight: 400;
  margin-top: 0.2em;
}

@media (max-width: 560px) {
  .site-header .container { height: 96px; }
  .brand { gap: 0.8rem; }
  .brand img { height: 56px; width: 56px; }
  .brand-text { font-size: 1.12rem; white-space: normal; max-width: 46vw; }
  .brand-text small { font-size: 0.7rem; line-height: 1.3; }
}

@media (max-width: 400px) {
  .brand-text { font-size: 1rem; max-width: 42vw; }
  .brand-text small { font-size: 0.64rem; }
}

.menu-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  display: flex;
  flex-direction: column;
  gap: 5px;
  z-index: 60;
}

.menu-btn span {
  display: block;
  width: 26px;
  height: 2px;
  background: var(--navy);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.menu-btn.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-btn.open span:nth-child(2) { opacity: 0; }
.menu-btn.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav-overlay {
  position: fixed;
  inset: 0;
  background: var(--navy);
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease;
}

.nav-overlay.open {
  opacity: 1;
  visibility: visible;
}

.nav-overlay nav {
  text-align: center;
}

.nav-close {
  position: absolute;
  top: 1.6rem;
  right: 1.8rem;
  background: none;
  border: none;
  cursor: pointer;
  color: #FAFAF8;
  font-size: 2.4rem;
  line-height: 1;
  font-family: "Inter", sans-serif;
  font-weight: 300;
  padding: 0.3rem 0.5rem;
  z-index: 55;
}

.nav-close:hover,
.nav-close:focus-visible {
  color: var(--accent);
}

@media (max-width: 560px) {
  .nav-close {
    top: 1.1rem;
    right: 1.2rem;
    font-size: 2.1rem;
  }
}

.nav-overlay a {
  display: block;
  font-family: "Newsreader", serif;
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  color: #FAFAF8;
  text-decoration: none;
  padding: 0.4em 0;
  font-weight: 400;
  transition: color 0.2s ease;
}

.nav-overlay a:hover,
.nav-overlay a:focus-visible {
  color: var(--accent);
}

.nav-overlay .nav-sub {
  margin-top: 2.5rem;
  font-family: "Inter", sans-serif;
  font-size: 0.95rem;
  color: #C9D0DC;
}

.nav-overlay .nav-sub a {
  display: inline;
  font-family: "Inter", sans-serif;
  font-size: 0.95rem;
  color: #C9D0DC;
  text-decoration: underline;
  padding: 0;
}

@media (prefers-reduced-motion: reduce) {
  .nav-overlay, .menu-btn span { transition: none; }
}

/* ---------- Hero (Ana Sayfa) ---------- */

.hero {
  padding: 4.5rem 1.5rem 3.5rem;
  max-width: var(--max-wide);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 3.5rem;
}

.hero-photo {
  flex: 0 0 auto;
  width: 300px;
  height: 340px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: 0 1px 28px rgba(11, 30, 61, 0.1);
}

.hero-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 20%;
}

.hero-text {
  flex: 1 1 auto;
  text-align: left;
  min-width: 0;
}

.hero .eyebrow {
  font-size: 0.95rem;
  color: var(--accent);
  letter-spacing: 0.02em;
  margin-bottom: 0.7rem;
  font-weight: 600;
}

.hero h1 {
  max-width: 18ch;
  margin: 0 0 1.1rem;
}

.hero .lede {
  max-width: 52ch;
  margin: 0;
  font-size: 1.18rem;
  color: var(--ink-soft);
}

.hero-rule {
  width: 48px;
  height: 2px;
  background: var(--accent);
  margin: 1.8rem 0;
  border: none;
}

@media (max-width: 780px) {
  .hero {
    flex-direction: column;
    text-align: center;
    padding: 3rem 1.5rem 2.5rem;
    gap: 2rem;
  }
  .hero-photo {
    width: 220px;
    height: 220px;
    border-radius: 50%;
  }
  .hero-text {
    text-align: center;
  }
  .hero h1 {
    margin: 0 auto 1rem;
  }
  .hero .lede {
    margin: 0 auto;
  }
  .hero-rule {
    margin: 1.6rem auto;
  }
}

/* ---------- Uzmanlık Alanları (icon grid) ---------- */

.expertise {
  background: var(--paper-alt);
  padding: 3.5rem 1.5rem;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.expertise h2 {
  text-align: center;
  margin-bottom: 2.2rem;
}

.expertise-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.8rem;
  max-width: var(--max-wide);
  margin: 0 auto;
}

@media (max-width: 860px) {
  .expertise-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 520px) {
  .expertise-grid { grid-template-columns: 1fr; }
}

.expertise-card {
  text-align: center;
}

.expertise-icon {
  width: 52px;
  height: 52px;
  margin: 0 auto 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent-soft);
}

.expertise-icon svg {
  width: 26px;
  height: 26px;
  stroke: var(--navy);
}

.expertise-card h3 {
  font-size: 1rem;
  margin-bottom: 0.4rem;
}

.expertise-card p {
  font-size: 0.92rem;
  margin: 0 auto;
}

/* ---------- Teaser links (home -> other pages) ---------- */

.teasers {
  padding: 3.5rem 1.5rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  max-width: var(--max-wide);
  margin: 0 auto;
}

@media (max-width: 720px) {
  .teasers { grid-template-columns: 1fr; }
}

.teaser-card {
  border: 1px solid var(--line);
  padding: 1.8rem;
  text-decoration: none;
  transition: border-color 0.2s ease, transform 0.2s ease;
  display: block;
}

.teaser-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.teaser-card h3 {
  color: var(--navy);
}

.teaser-card p {
  font-size: 0.93rem;
  margin-bottom: 0;
}

.teaser-card .arrow {
  color: var(--accent);
  font-size: 0.85rem;
  margin-top: 0.8rem;
  display: inline-block;
}

/* ---------- Generic page header (non-home pages) ---------- */

.page-hero {
  padding: 3.5rem 1.5rem 2.5rem;
  text-align: center;
  border-bottom: 1px solid var(--line);
  background: var(--paper-alt);
}

.page-hero .eyebrow {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

/* ---------- Hakkımda page ---------- */

.about-wrap {
  padding: 3.5rem 1.5rem;
  max-width: var(--max);
  margin: 0 auto;
}

.about-wrap p { max-width: none; }

.about-wrap h2 {
  font-size: 1.5rem;
  margin: 2.2rem 0 0.9rem;
}

.about-wrap h2:first-child { margin-top: 0; }

/* ---------- Akademik page: details/summary categories ---------- */

.akademik-wrap {
  padding: 3rem 1.5rem 4rem;
  max-width: var(--max-wide);
  margin: 0 auto;
}

.akademik-intro {
  max-width: var(--max);
  margin: 0 auto 2.5rem;
  text-align: center;
}

.metrics-row {
  display: flex;
  justify-content: center;
  gap: 2.5rem;
  flex-wrap: wrap;
  margin: 2rem auto 3rem;
  text-align: center;
}

.metric {
  min-width: 100px;
}

.metric .num {
  font-family: "Newsreader", serif;
  font-size: 2.1rem;
  color: var(--navy);
  display: block;
}

.metric .label {
  font-size: 0.8rem;
  color: var(--ink-soft);
}

details.category {
  border-bottom: 1px solid var(--line);
}

details.category summary {
  cursor: pointer;
  list-style: none;
  padding: 1.3rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: "Newsreader", serif;
  font-size: 1.25rem;
  color: var(--navy);
}

details.category summary::-webkit-details-marker { display: none; }

details.category summary .count {
  font-family: "Inter", sans-serif;
  font-size: 0.82rem;
  color: var(--ink-soft);
  font-weight: 400;
  margin-left: 1rem;
}

details.category summary .plus {
  font-size: 1.4rem;
  color: var(--accent);
  transition: transform 0.2s ease;
  margin-left: auto;
  padding-left: 1rem;
}

details.category[open] summary .plus { transform: rotate(45deg); }

.pub-list {
  margin: 0 0 1.8rem;
  padding: 0 0 0 1.2rem;
}

.pub-list li {
  margin-bottom: 0.9rem;
  color: var(--ink-soft);
  font-size: 0.94rem;
  line-height: 1.55;
}

.pub-note {
  font-size: 0.88rem;
  color: var(--ink-soft);
  font-style: italic;
  margin-bottom: 1.2rem;
}

.pub-list .idx {
  font-style: normal;
  color: var(--navy);
}

/* ---------- İletişim page ---------- */

.contact-wrap {
  padding: 3.5rem 1.5rem 4rem;
  max-width: var(--max);
  margin: 0 auto;
}

.contact-block {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.8rem;
  align-items: flex-start;
}

.contact-icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--accent-soft);
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-icon svg {
  width: 20px;
  height: 20px;
  stroke: var(--navy);
}

.contact-block h3 {
  margin-bottom: 0.25rem;
  font-size: 1rem;
}

.contact-block p {
  margin: 0;
  font-size: 0.96rem;
}

.contact-block a {
  color: var(--navy);
  font-weight: 500;
  text-decoration: none;
  border-bottom: 1px solid var(--accent);
}

/* ---------- Bilgilendirme (blog index) placeholder ---------- */

.blog-empty {
  padding: 4rem 1.5rem;
  text-align: center;
  max-width: var(--max);
  margin: 0 auto;
}

/* ---------- Footer ---------- */

.site-footer {
  background: var(--navy);
  color: #C9D0DC;
  padding: 3rem 1.5rem 2rem;
  margin-top: 2rem;
}

.site-footer .container {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 2rem;
}

.site-footer h4 {
  color: #FAFAF8;
  font-family: "Inter", sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  margin-bottom: 0.8rem;
}

.site-footer p, .site-footer a {
  color: #C9D0DC;
  font-size: 0.9rem;
}

.site-footer a { text-decoration: none; }
.site-footer a:hover { color: #FAFAF8; }

.footer-bottom {
  max-width: var(--max-wide);
  margin: 2.5rem auto 0;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255,255,255,0.12);
  font-size: 0.8rem;
  color: #8894A6;
  text-align: center;
}

.footer-social {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-social svg {
  width: 18px;
  height: 18px;
  stroke: #C9D0DC;
}