/* ============================================================
   Onur Karasurmeli — Portfolio
   Design system: quiet sidebar nav + centered single column,
   hairline rules, serif display type, restrained blue accent.
   ============================================================ */

:root {
  --color-bg: #ffffff;
  --color-text: #1c1c1c;
  --color-text-soft: #4a4a4a;
  --color-nav: #9a9a9a;
  --color-nav-active: #1c1c1c;
  --color-rule: #d9d9d9;
  --color-accent: #3f7cc9;
  --color-accent-soft: #eaf1fb;
  --font-display: Georgia, "Iowan Old Style", "Palatino Linotype", Palatino, serif;
  --font-body: Georgia, "Iowan Old Style", "Palatino Linotype", Palatino, serif;
  --font-nav: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --max-content: 760px;
  --gutter: 40px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1c1c1c;
    --color-text: #ffffff;
    --color-text-soft: #d9d9d9;
    --color-nav: #9a9a9a;
    --color-nav-active: #ffffff;
    --color-rule: #4a4a4a;
    --color-accent: #3f7cc9;
    --color-accent-soft: #2c3a4f;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

/* ---------- Logo ---------- */

.logo {
  height: 40px;
  width: auto;
  display: block;
}

.logo--light { display: block; }
.logo--dark { display: none; }

@media (prefers-color-scheme: dark) {
  .logo--light { display: none; }
  .logo--dark { display: block; }
}

/* ---------- Layout shell ---------- */

.shell {
  display: flex;
  align-items: flex-start;
  max-width: 1180px;
  margin: 0 auto;
  padding: 96px var(--gutter) 120px;
  gap: 64px;
}

/* ---------- Sidebar nav ---------- */

.sidenav {
  flex: 0 0 200px;
  position: sticky;
  top: 96px;
}

.sidenav__brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 28px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.2px;
  text-decoration: none;
}

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

.sidenav li { margin: 0 0 14px; }

.sidenav a {
  font-family: var(--font-nav);
  font-size: 15px;
  color: var(--color-nav);
  text-decoration: none;
  transition: color 0.15s ease;
  position: relative;
}

.sidenav a:hover { color: var(--color-text); text-decoration: none; }

.sidenav a.is-active {
  color: var(--color-nav-active);
  padding-right: 12px;
}

.sidenav a.is-active::after {
  content: "";
  position: absolute;
  right: 0;
  top: 2px;
  width: 1px;
  height: 16px;
  background: var(--color-text);
  animation: blink 1.1s steps(1) infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

/* ---------- Main column ---------- */

.main { flex: 1 1 auto; min-width: 0; }

.page-title {
  font-family: var(--font-display);
  font-size: 34px;
  font-weight: 700;
  margin: 0 0 22px;
}

.rule {
  border: none;
  border-top: 1px solid var(--color-rule);
  margin: 0 0 48px;
}

.rule--tight { margin: 32px 0; }
.rule--short { width: 90px; margin: 32px auto; border-top: 1px solid var(--color-rule); }

.content { max-width: var(--max-content); margin: 0 auto; }

/* ---------- About page ---------- */

.avatar {
  width: 190px;
  height: 190px;
  border-radius: 50%;
  margin: 0 auto 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(155deg, #eef3fa, #dfe9f6);
  border: 1px solid var(--color-rule);
  font-family: var(--font-display);
  font-size: 56px;
  font-weight: 700;
  color: var(--color-accent);
}

.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
}

.social-row {
  display: flex;
  justify-content: center;
  gap: 14px;
  margin-bottom: 8px;
}

.social-row a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.15s ease, background 0.15s ease;
}

.social-row a:hover { background: #2f649f; transform: translateY(-2px); text-decoration: none; }

.social-row svg { width: 18px; height: 18px; fill: #fff; }

.cv-button {
  display: block;
  text-align: center;
  border: 1px solid var(--color-rule);
  padding: 16px 20px;
  font-family: var(--font-nav);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 2.5px;
  color: var(--color-text);
  text-transform: uppercase;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.cv-button:hover {
  background: var(--color-accent-soft);
  border-color: var(--color-accent);
  text-decoration: none;
}

.lede {
  text-align: center;
  font-family: var(--font-nav);
  font-size: 12px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-nav);
  margin: 0 0 6px;
}

.about-text p { margin: 0 0 20px; color: var(--color-text-soft); }
.about-text strong { color: var(--color-text); }

.location-line {
  text-align: center;
  font-family: var(--font-nav);
  font-size: 14px;
  color: var(--color-nav);
  margin: -8px 0 32px;
}

/* ---------- Timeline blocks (Education / Experience) ---------- */

.entry {
  text-align: center;
  margin-bottom: 8px;
}

.entry + .rule--tight { margin: 40px 0; }

.entry__org {
  font-family: var(--font-nav);
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-accent);
  margin: 0 0 10px;
}

.entry__role {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  margin: 0 0 2px;
}

.entry__company {
  font-style: italic;
  color: var(--color-text-soft);
  margin: 0 0 14px;
  font-size: 17px;
}

.entry__meta {
  font-family: var(--font-nav);
  font-size: 13px;
  color: var(--color-nav);
  margin: 0 0 18px;
}

.entry__body {
  text-align: left;
  color: var(--color-text-soft);
}

.entry__body ul {
  margin: 0;
  padding-left: 20px;
}

.entry__body li { margin-bottom: 10px; }

.entry__stat {
  display: inline-block;
  margin: 0 10px 18px;
  text-align: center;
}

.entry__stat b {
  display: block;
  font-family: var(--font-display);
  font-size: 20px;
}

.entry__stat span {
  font-family: var(--font-nav);
  font-size: 11px;
  color: var(--color-nav);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* ---------- Table-style rows (Projects) ---------- */

.proj-table {
  border: 1px solid var(--color-rule);
  margin-bottom: 40px;
}

.proj-table__head {
  background: #fafafa;
  padding: 16px 20px;
  border-bottom: 1px solid var(--color-rule);
  text-align: center;
}

@media (prefers-color-scheme: dark) {
  .proj-table__head {
    background: var(--color-accent-soft);
  }
}

.proj-table__head a {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
}

.proj-table__body {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px;
  padding: 22px 24px;
}

.proj-table__stack {
  font-family: var(--font-nav);
  font-size: 12.5px;
  color: var(--color-text-soft);
  letter-spacing: 0.3px;
}

.proj-table__desc {
  flex: 1 1 260px;
  color: var(--color-text-soft);
  font-size: 15.5px;
}

.proj-table__links {
  display: flex;
  gap: 16px;
  font-family: var(--font-nav);
  font-size: 13.5px;
  white-space: nowrap;
}

/* ---------- Skills ---------- */

.skill-group { margin-bottom: 36px; }

.skill-group h3 {
  font-family: var(--font-nav);
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-accent);
  margin: 0 0 14px;
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.pill {
  font-family: var(--font-nav);
  font-size: 13.5px;
  color: var(--color-text-soft);
  border: 1px solid var(--color-rule);
  border-radius: 999px;
  padding: 7px 16px;
}

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

.site-footer {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 30px;
  padding: 60px 0;
}

.site-footer__row {
  display: flex;
  align-items: center;
  gap: 24px;
}

.site-footer__brand {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
}

.site-footer .social-row {
  margin-bottom: 0;
}

.site-footer .social-row a {
  background: var(--color-accent-soft);
}

.site-footer .social-row svg {
  fill: var(--color-accent);
}

/* ---------- Mobile nav ---------- */

.mobile-topbar { display: none; }

/* ---------- Responsive ---------- */

@media (max-width: 860px) {
  .shell {
    flex-direction: column;
    padding: 24px 22px 80px;
    gap: 8px;
  }

  .sidenav {
    position: static;
    width: 100%;
    display: none;
    border-bottom: 1px solid var(--color-rule);
    padding-bottom: 18px;
    margin-bottom: 28px;
  }

  .sidenav.is-open { display: block; }

  .mobile-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 0;
    border-bottom: 1px solid var(--color-rule);
    margin-bottom: 24px;
  }

  .mobile-topbar__brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-display);
    font-size: 18px;
    font-weight: 700;
    text-decoration: none;
  }

  .mobile-topbar__toggle {
    font-family: var(--font-nav);
    font-size: 13px;
    letter-spacing: 1px;
    text-transform: uppercase;
    background: none;
    border: 1px solid var(--color-rule);
    padding: 8px 14px;
    border-radius: 4px;
    color: var(--color-text);
    cursor: pointer;
  }

  .page-title { font-size: 28px; }
  .avatar { width: 150px; height: 150px; font-size: 44px; }
}