:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f5f6f8;
  --color-text: #1d1d1f;
  --color-text-muted: #55565a;
  --color-primary: #0a84ff;
  --color-primary-dark: #006edb;
  --color-border: rgba(0, 0, 0, 0.08);
  --color-header-bg: rgba(255, 255, 255, 0.85);
  --btn-primary-text: #ffffff;
  --max-width: 1100px;
  --radius: 14px;
  --transition: 0.2s ease-in-out;
  --ease-apple: cubic-bezier(0.16, 1, 0.3, 1);
  color-scheme: light;
}

[data-theme="dark"] {
  --color-bg: #0f1115;
  --color-bg-alt: #161a21;
  --color-text: #e8e8ea;
  --color-text-muted: #9aa0ac;
  --color-primary: #5ec6ff;
  --color-primary-dark: #2f9fe0;
  --color-border: rgba(255, 255, 255, 0.1);
  --color-header-bg: rgba(15, 17, 21, 0.85);
  --btn-primary-text: #0f1115;
  color-scheme: dark;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, "Segoe UI", system-ui, Roboto, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  transition:
    background-color var(--transition),
    color var(--transition);
}

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

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

a:hover {
  color: var(--color-primary-dark);
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

/* Header / Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-header-bg);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--color-border);
  transition:
    background-color var(--transition),
    border-color var(--transition);
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 1rem;
}

.logo {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-text);
}

.logo span {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--color-text);
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--color-primary);
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.icon-btn,
.lang-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  background-color: var(--color-bg-alt);
  color: var(--color-text);
  cursor: pointer;
  transition:
    transform var(--transition),
    background-color var(--transition);
  font-size: 0.95rem;
  font-weight: 600;
}

.icon-btn:hover,
.lang-btn:hover {
  transform: translateY(-2px);
  color: var(--color-primary);
}

.theme-icon-dark {
  display: none;
}

[data-theme="dark"] .theme-icon-light {
  display: none;
}

[data-theme="dark"] .theme-icon-dark {
  display: inline;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
}

/* Hero */
.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  min-height: 80vh;
  flex-wrap: wrap;
}

.hero-greeting {
  color: var(--color-primary);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.hero-text h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
  margin-bottom: 0.5rem;
}

.hero-subtitle {
  color: var(--color-text-muted);
  font-size: 1.25rem;
  margin-bottom: 1.5rem;
}

.hero-image img {
  border-radius: 50%;
  width: 280px;
  height: 280px;
  object-fit: cover;
  object-position: center;
  border: 3px solid var(--color-primary);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  transition:
    transform var(--transition),
    background-color var(--transition);
}

.btn-primary {
  background-color: var(--color-primary);
  color: var(--btn-primary-text);
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-2px);
  color: var(--btn-primary-text);
}

.btn-secondary {
  position: relative;
  border: 1px solid var(--color-primary);
  color: var(--color-primary);
  overflow: hidden;
  z-index: 1;
  transition: color 0.45s var(--ease-apple);
}

.btn-secondary::before {
  content: "";
  position: absolute;
  inset: 0;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.45s var(--ease-apple);
  z-index: -1;
}

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

.btn-secondary:hover::before {
  transform: scaleX(1);
}

/* Sections */
section {
  padding: 5rem 0;
}

.section-title {
  font-size: 2rem;
  margin-bottom: 2rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: "";
  display: block;
  width: 50%;
  height: 3px;
  background-color: var(--color-primary);
  margin-top: 0.5rem;
}

.about p {
  color: var(--color-text-muted);
  max-width: 700px;
}

/* Projects — Apple-style product showcase */
.projects {
  overflow: clip;
}

.project-showcase {
  display: flex;
  flex-direction: column;
  gap: clamp(4rem, 10vw, 8rem);
  margin-inline: clamp(-1.5rem, -4vw, -3rem);
  padding: 1.5rem clamp(1.5rem, 4vw, 3rem);
}

.project-feature {
  --accent: var(--color-primary);
  display: grid;
  grid-template-columns: minmax(230px, 0.68fr) minmax(0, 1.6fr);
  align-items: center;
  gap: clamp(1.5rem, 4vw, 3rem);
}

.project-feature:nth-child(even) {
  grid-template-columns: minmax(0, 1.6fr) minmax(230px, 0.68fr);
}

.project-feature:nth-child(even) .project-feature-info {
  order: 2;
}

.project-feature:nth-child(even) .project-feature-window {
  order: 1;
}

.project-feature-info {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.9rem;
}

.project-feature-logo {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  padding: 8px;
  background-color: var(--accent);
  box-shadow: 0 10px 30px -8px
    color-mix(in srgb, var(--accent) 70%, transparent);
  object-fit: contain;
}

/* Logo koloru tożsamego z akcentem — wyjątek z białym tłem i obwódką */
.project-feature-logo--outline {
  background-color: #ffffff;
  border: 2px solid var(--accent);
  padding: 6px;
}

/* Logo zbyt szczegółowe na tle paddingu — wypełnia kafelek jak reszta ikon */
.project-feature-logo--cover {
  padding: 0;
  object-fit: cover;
}

.project-feature-info h3 {
  font-size: clamp(1.4rem, 2.4vw, 1.9rem);
  letter-spacing: -0.01em;
}

.project-feature-info p {
  color: var(--color-text-muted);
  max-width: 34ch;
}

.project-feature-info .btn-secondary {
  border-color: var(--accent);
  color: var(--accent);
}

.project-feature-info .btn-secondary::before {
  background-color: var(--accent);
}

.project-feature-info .btn-secondary:hover {
  color: #ffffff;
}

.project-feature-window {
  --parallax-y: 0px;
  position: relative;
  border-radius: 9px;
  overflow: hidden;
  background: #1a1b1e;
  box-shadow:
    0 40px 70px -24px color-mix(in srgb, var(--accent) 50%, rgba(0, 0, 0, 0.55)),
    0 16px 32px -18px color-mix(in srgb, var(--accent) 40%, transparent);
  isolation: isolate;
  transform: translateY(var(--parallax-y));
}

.project-feature-window::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
  pointer-events: none;
}

.project-feature-window img {
  width: 100%;
  display: block;
}

/* Scroll-reveal entrance for product windows */
.js .project-feature.reveal {
  opacity: 0;
  translate: 0 48px;
  transition:
    opacity 0.9s var(--ease-apple),
    translate 0.9s var(--ease-apple);
}

.js .project-feature.reveal .project-feature-window {
  transition:
    transform 0.9s var(--ease-apple),
    box-shadow var(--transition);
  transform: translateY(var(--parallax-y)) scale(0.94);
}

.js .project-feature.reveal.is-visible .project-feature-window {
  transform: translateY(var(--parallax-y)) scale(1);
}

.js .project-feature.reveal .project-feature-info > * {
  opacity: 0;
  translate: 0 16px;
  transition:
    opacity 0.7s var(--ease-apple),
    translate 0.7s var(--ease-apple);
}

.js .project-feature.reveal.is-visible .project-feature-info > * {
  opacity: 1;
  translate: 0 0;
}

.js .project-feature.reveal .project-feature-info > *:nth-child(1) {
  transition-delay: 0.05s;
}
.js .project-feature.reveal .project-feature-info > *:nth-child(2) {
  transition-delay: 0.12s;
}
.js .project-feature.reveal .project-feature-info > *:nth-child(3) {
  transition-delay: 0.19s;
}
.js .project-feature.reveal .project-feature-info > *:nth-child(4) {
  transition-delay: 0.26s;
}

/* Contact */
.contact-email {
  font-size: 1.25rem;
  font-weight: 600;
  display: inline-block;
  margin: 1rem 0;
}

.social-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  margin-top: 1rem;
}

/* Footer */
.site-footer {
  text-align: center;
  padding: 2rem 0;
  color: var(--color-text-muted);
  border-top: 1px solid var(--color-border);
}

/* Back to top */
.back-to-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background-color: var(--color-primary);
  color: var(--btn-primary-text);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition:
    opacity var(--transition),
    transform var(--transition);
  z-index: 99;
}

.back-to-top::before {
  content: "";
  display: block;
  width: 10px;
  height: 10px;
  margin: 0 auto;
  border-top: 2px solid currentColor;
  border-right: 2px solid currentColor;
  transform: translateY(2px) rotate(-45deg);
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  transform: translateY(-3px);
}

/* Reveal on scroll (Apple-style fade + slide) */
.js .reveal {
  opacity: 0;
  translate: 0 28px;
  transition:
    opacity 0.7s var(--ease-apple),
    translate 0.7s var(--ease-apple);
}

.js .reveal.is-visible {
  opacity: 1;
  translate: 0 0;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .js .reveal,
  .js .project-feature.reveal,
  .js .project-feature.reveal .project-feature-window,
  .js .project-feature.reveal .project-feature-info > * {
    opacity: 1;
    translate: 0 0;
    transform: none;
    transition: none;
  }

  .project-feature-window,
  .btn,
  .icon-btn,
  .lang-btn,
  .back-to-top {
    transition: none;
  }
}

/* Responsive */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background-color: var(--color-bg);
    flex-direction: column;
    align-items: center;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition);
    border-bottom: 1px solid var(--color-border);
  }

  .nav-links.open {
    max-height: 300px;
  }

  .nav-links li {
    width: 100%;
    text-align: center;
  }

  .nav-links a {
    display: block;
    padding: 1rem 0;
  }

  .hero {
    flex-direction: column-reverse;
    text-align: center;
    min-height: auto;
    padding-top: 3rem;
  }

  .project-feature,
  .project-feature:nth-child(even) {
    grid-template-columns: 1fr;
  }

  .project-feature-info,
  .project-feature:nth-child(even) .project-feature-info {
    order: 2;
    align-items: center;
    text-align: center;
  }

  .project-feature-window,
  .project-feature:nth-child(even) .project-feature-window {
    order: 1;
  }

  .project-feature-info p {
    max-width: none;
  }
}