/* ==========================================================================
   Ertunç Özbay — Personal Engineering Website
   Clean, restrained, readable stylesheet (Light & Dark modes)
   ========================================================================== */

:root,
[data-theme="light"] {
  --bg: #f7f7f5;
  --bg-surface: #ffffff;
  --bg-muted: #efefec;
  --bg-code: #f1f1ee;
  --text: #1c1c1c;
  --text-secondary: #4a4a48;
  --text-muted: #6e6e6a;
  --border: #dcdcd6;
  --accent: #1d4ed8;
  --accent-hover: #1e40af;
  --accent-subtle: #eff6ff;
  --status-done-bg: #ecfdf5;
  --status-done-text: #065f46;
  --status-done-border: #a7f3d0;
  --status-wip-bg: #fffbeb;
  --status-wip-text: #92400e;
  --status-wip-border: #fde68a;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --max-width: 960px;
  --reading-width: 720px;
  --radius: 6px;
}

[data-theme="dark"] {
  --bg: #141517;
  --bg-surface: #1c1d21;
  --bg-muted: #25262b;
  --bg-code: #18191c;
  --text: #e5e7eb;
  --text-secondary: #b0b5bd;
  --text-muted: #848a94;
  --border: #2e3036;
  --accent: #60a5fa;
  --accent-hover: #93c5fd;
  --accent-subtle: rgba(96, 165, 250, 0.12);
  --status-done-bg: rgba(16, 185, 129, 0.12);
  --status-done-text: #6ee7b7;
  --status-done-border: rgba(16, 185, 129, 0.3);
  --status-wip-bg: rgba(245, 158, 11, 0.12);
  --status-wip-text: #fcd34d;
  --status-wip-border: rgba(245, 158, 11, 0.3);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* Accessibility */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius);
  z-index: 1000;
  text-decoration: none;
}

.skip-link:focus {
  top: 0.75rem;
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.reading-width {
  max-width: var(--reading-width);
}

/* Typography */
h1, h2, h3, h4 {
  color: var(--text);
  font-weight: 600;
  line-height: 1.3;
  margin-top: 0;
  letter-spacing: -0.015em;
}

h1 {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

h2 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}

h3 {
  font-size: 1.1rem;
  margin-bottom: 0.4rem;
}

p {
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

ul, ol {
  color: var(--text-secondary);
  padding-left: 1.25rem;
  margin-top: 0;
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.35rem;
}

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

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--bg-code);
  border: 1px solid var(--border);
  padding: 0.12rem 0.35rem;
  border-radius: 4px;
  color: var(--text);
}

pre {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.55;
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  overflow-x: auto;
  margin: 0 0 1.25rem 0;
}

pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

/* Header & Navigation */
.site-header {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 3.75rem;
  gap: 1rem;
  flex-wrap: wrap;
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
}

.site-brand {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: var(--text);
}

.site-brand:hover {
  text-decoration: none;
}

.brand-name {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text);
}

.brand-role {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.nav-links {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin: 0;
  padding: 0;
}

.nav-links li {
  margin: 0;
}

.nav-links a {
  display: inline-block;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius);
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--text);
  background: var(--bg-muted);
}

/* Theme Switcher */
.theme-switcher {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg);
}

.theme-btn {
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-sans);
  font-size: 0.8rem;
  padding: 0.3rem 0.6rem;
  cursor: pointer;
}

.theme-btn:hover {
  color: var(--text);
}

.theme-btn.active {
  background: var(--bg-surface);
  color: var(--text);
  font-weight: 600;
}

/* Main Content & Sections */
main {
  padding: 2.5rem 0 4rem;
}

.hero,
.page-header {
  padding-bottom: 2rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.hero-eyebrow,
.section-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.hero-lead {
  font-size: 1.05rem;
  max-width: 68ch;
  color: var(--text-secondary);
}

.hero-actions,
.button-row,
.card-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1rem;
}

.section-block {
  margin-bottom: 2.75rem;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 500;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-surface);
  color: var(--text);
  cursor: pointer;
  text-decoration: none;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.btn:hover {
  background: var(--bg-muted);
  color: var(--text);
  text-decoration: none;
}

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: #ffffff;
}

/* Cards & Grids */
.card-grid,
.card-grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
  gap: 1.25rem;
}

.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card h3 a {
  color: var(--text);
  text-decoration: none;
}

.card h3 a:hover {
  color: var(--accent);
  text-decoration: underline;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

/* Badges & Tags */
.badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: var(--bg-muted);
  color: var(--text-secondary);
}

.badge-completed {
  background: var(--status-done-bg);
  color: var(--status-done-text);
  border-color: var(--status-done-border);
}

.badge-active {
  background: var(--status-wip-bg);
  color: var(--status-wip-text);
  border-color: var(--status-wip-border);
}

.tag-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0;
  margin: 0.75rem 0;
}

.tag-list li {
  margin: 0;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  background: var(--bg-muted);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

/* Code Window */
.code-window {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-code);
  margin-bottom: 1.25rem;
  overflow: hidden;
}

.code-window-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.45rem 0.85rem;
  background: var(--bg-muted);
  border-bottom: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.code-dots {
  display: none;
}

.copy-code-btn {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  padding: 0.2rem 0.55rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg-surface);
  color: var(--text-secondary);
  cursor: pointer;
}

.copy-code-btn:hover {
  color: var(--text);
  background: var(--bg);
}

.code-window pre {
  border: none;
  border-radius: 0;
  margin: 0;
}

/* Callout & Notes */
.callout-box,
.project-notes {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 0.9rem 1.1rem;
  margin: 1rem 0;
}

.callout-title {
  display: block;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text);
  margin-bottom: 0.35rem;
}

/* Tables */
.table-wrapper {
  overflow-x: auto;
  margin-bottom: 1.25rem;
}

table,
.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
}

th, td {
  text-align: left;
  padding: 0.65rem 0.85rem;
  border-bottom: 1px solid var(--border);
}

th {
  background: var(--bg-muted);
  color: var(--text);
  font-weight: 600;
}

td {
  color: var(--text-secondary);
}

/* Video Container & Placeholder */
.video-showcase {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1.5rem;
}

.video-placeholder {
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  padding: 2rem 1.25rem;
  text-align: center;
}

.video-play-icon {
  display: none;
}

/* Images & Gallery */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.gallery-item {
  margin: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.gallery-item img {
  display: block;
  width: 100%;
  height: 220px;
  object-fit: cover;
  cursor: zoom-in;
}

.gallery-item figcaption {
  padding: 0.65rem 0.85rem;
  font-size: 0.82rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}

/* Breadcrumbs */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

/* Lightbox */
.lightbox-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  z-index: 2000;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.lightbox-backdrop[hidden] {
  display: none;
}

.lightbox-Backdrop-img {
  max-width: 92vw;
  max-height: 82vh;
  border-radius: 4px;
}

.lightbox-caption {
  color: #e5e7eb;
  font-size: 0.9rem;
  margin-top: 0.75rem;
  text-align: center;
}

.lightbox-close {
  position: absolute;
  top: 1rem;
  right: 1.25rem;
  background: #27272a;
  color: #fff;
  border: 1px solid #3f3f46;
  padding: 0.4rem 0.75rem;
  border-radius: 4px;
  cursor: pointer;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-surface);
  padding: 1.5rem 0;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-links {
  list-style: none;
  display: flex;
  gap: 1rem;
  margin: 0;
  padding: 0;
}

.footer-links li {
  margin: 0;
}

/* Additional Layout & Component Classes */
.site-brand {
  flex-direction: row;
  align-items: center;
  gap: 0.65rem;
  font-weight: 600;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: 4px;
  background: var(--bg-muted);
  border: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
}

.brand-subtitle {
  display: block;
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--text-muted);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  flex-wrap: wrap;
}

.nav-toggle {
  display: none;
}

.nav-list {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.2rem;
  margin: 0;
  padding: 0;
}

.nav-list li {
  margin: 0;
}

.nav-link {
  display: inline-block;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius);
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
}

.nav-link:hover,
.nav-link[aria-current="page"] {
  color: var(--text);
  background: var(--bg-muted);
  text-decoration: none;
}

.workshop-hero {
  padding-bottom: 2rem;
  margin-bottom: 2.25rem;
  border-bottom: 1px solid var(--border);
}

.workshop-eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
}

.stats-strip,
.meta-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 0.85rem;
  margin-top: 1.5rem;
}

.stat-pill,
.meta-item {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
}

.stat-value,
.meta-value {
  display: block;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
}

.stat-label,
.meta-label {
  display: block;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

.video-frame-wrapper {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.video-frame-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: 0;
}