:root {
  --bg-color: #000000;
  --card-bg: #0a0a0a;
  --text-primary: #ffffff;
  --text-secondary: #888888;
  --accent-color: #ffffff;
  --accent-glow: rgba(255, 255, 255, 0.1);
  --border-color: rgba(255, 255, 255, 0.1);
  --glass-bg: rgba(255, 255, 255, 0.03);
  
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 6rem;
  --radius-md: 0px;
  --radius-lg: 0px;
  
  --transition: all 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  scrollbar-width: thin;
  scrollbar-color: #333 #000;
}

::-webkit-scrollbar {
  width: 4px;
}

::-webkit-scrollbar-track {
  background: #000;
}

::-webkit-scrollbar-thumb {
  background: #333;
}

::-webkit-scrollbar-thumb:hover {
  background: #666;
}

html {
  scroll-behavior: smooth;
  background: #000;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.5;
  overflow-x: hidden;
  letter-spacing: -0.01em;
}

h1, h2, h3 {
  font-weight: 500;
  line-height: 0.9;
  text-transform: uppercase;
  letter-spacing: -0.04em;
}

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

ul {
  list-style: none;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

section {
  padding: var(--spacing-xl) 0;
}

header {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--text-primary);
}

.logo img {
  height: 80px;
  width: auto;
  margin-left: -15px;
  filter: brightness(1.5);
}

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-links a {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
}

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

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  text-align: left;
  overflow: hidden;
  padding-top: 100px;
}

.hero-content {
  position: relative;
  z-index: 10;
  max-width: 800px;
}

.hero h1 {
  font-size: clamp(4rem, 12vw, 10rem);
  margin-bottom: var(--spacing-md);
  color: #fff;
}

.hero p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 400px;
  margin: 0 0 var(--spacing-lg);
  line-height: 1.4;
}

#typewriter-text::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 1em;
  background-color: var(--text-primary);
  margin-left: 2px;
  vertical-align: middle;
  animation: blink 0.7s infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.arc-container {
  position: absolute;
  top: 50%;
  right: -10%;
  transform: translateY(-50%) rotate(-15deg);
  width: 80vh;
  height: 80vh;
  z-index: 1;
  pointer-events: none;
}

.arc {
  width: 100%;
  height: 100%;
  border: 2px solid rgba(255, 255, 255, 0.1);
  border-top: 2px solid rgba(255, 255, 255, 0.8);
  border-radius: 50%;
  filter: blur(1px);
  box-shadow: 0 0 50px rgba(255, 255, 255, 0.1), inset 0 0 50px rgba(255, 255, 255, 0.05);
  animation: rotateArc 15s linear infinite;
  position: relative;
}

.arc::before {
  content: '';
  position: absolute;
  top: -10px;
  left: 50%;
  width: 20px;
  height: 20px;
  background: #fff;
  border-radius: 50%;
  filter: blur(10px);
  box-shadow: 0 0 30px #fff;
}

@keyframes rotateArc {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.hero-gradient {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 70% 30%, rgba(255, 255, 255, 0.05) 0%, transparent 70%);
  pointer-events: none;
}

.btn {
  display: inline-block;
  padding: 1rem 2.5rem;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid var(--border-color);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background-color: #fff;
  color: #000;
}

.btn-primary:hover {
  background-color: #000;
  color: #fff;
  border-color: #fff;
}

.btn-outline {
  background: transparent;
  color: #fff;
}

.btn-outline:hover {
  background: #fff;
  color: #000;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-disabled {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-secondary);
  border-color: var(--border-color);
  cursor: not-allowed;
  pointer-events: none;
  opacity: 0.6;
}

.filter-controls {
  display: flex;
  justify-content: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
  flex-wrap: wrap;
}

.filter-controls label {
  padding: 0.6rem 1.5rem;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 100px;
  cursor: pointer;
  transition: var(--transition);
  color: var(--text-secondary);
}

.filter-controls label:hover {
  border-color: var(--accent-color);
  color: var(--text-primary);
}

/* Hide Radio Buttons */
input[type="radio"] {
  display: none;
}

/* Filter Logic */
#filter-all:checked ~ .filter-controls label[for="filter-all"],
#filter-verandio:checked ~ .filter-controls label[for="filter-verandio"],
#filter-kyokushin:checked ~ .filter-controls label[for="filter-kyokushin"],
#filter-vanklasse:checked ~ .filter-controls label[for="filter-vanklasse"] {
  background: var(--accent-color);
  color: #000;
  border-color: var(--accent-color);
}

#projecten {
  perspective: 1000px;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(400px, 1fr));
  gap: 1px;
  background: var(--border-color);
  border: 1px solid var(--border-color);
}

.project-card {
  background: #0a0a0a;
  padding: var(--spacing-xl) var(--spacing-lg);
  transition: var(--transition);
  display: none;
  transform-style: preserve-3d;
  border: 1px solid var(--border-color);
}

#filter-all:checked ~ .projects-grid .project-card { display: block; }
#filter-verandio:checked ~ .projects-grid .project-card.verandio { display: block; }
#filter-kyokushin:checked ~ .projects-grid .project-card.kyokushin { display: block; }
#filter-vanklasse:checked ~ .projects-grid .project-card.vanklasse { display: block; }

.project-card:hover {
  background: #050505;
  transform: rotateY(5deg) rotateX(2deg);
  box-shadow: -20px 20px 60px rgba(255, 255, 255, 0.03);
}

.project-preview {
  height: 400px;
  background: #000;
  border: 1px solid var(--border-color);
  margin-bottom: var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-md);
  position: relative;
}

.project-preview::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to bottom, transparent, rgba(255,255,255,0.05));
  pointer-events: none;
}

.project-preview img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  transition: var(--transition);
  filter: grayscale(1) brightness(1.2) contrast(1.1);
}

.project-card:hover .project-preview img {
  transform: scale(1.1) translateZ(50px);
  filter: grayscale(0) brightness(1);
}

.project-content h3 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
}

.badge {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
}

@supports (animation-timeline: view()) {
  .project-card {
    animation: reveal 1s linear both;
    animation-timeline: view();
    animation-range: entry 10% cover 30%;
  }
}

@keyframes reveal {
  from {
    opacity: 0.2;
    transform: translateY(50px) rotateX(10deg);
  }
  to {
    opacity: 1;
    transform: translateY(0) rotateX(0);
  }
}

.project-actions {
  display: flex;
  gap: var(--spacing-md);
}

.project-details {
  margin-top: var(--spacing-xl);
}

.detail-block {
  background: var(--card-bg);
  padding: var(--spacing-xl);
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-lg);
  border: 1px solid var(--border-color);
}

.detail-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}

.detail-item h4 {
  color: var(--accent-color);
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 1px;
}

.about-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-xl);
  align-items: flex-start;
  max-width: 800px;
  margin: 0 auto;
}

.about-content h2 {
  font-size: 4rem;
  margin-bottom: var(--spacing-lg);
}

.skills-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.skill-item {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
}

.contact-form {
  max-width: 800px;
  margin: 0 auto;
  background: #0a0a0a;
  padding: var(--spacing-xl);
  border: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

.contact-form::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, #fff, transparent);
  animation: scanLine 3s linear infinite;
}

@keyframes scanLine {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.form-group {
  margin-bottom: var(--spacing-lg);
  position: relative;
}

.form-group label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  display: block;
}

.form-group input, 
.form-group textarea {
  width: 100%;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  border-radius: 0;
  padding: 1rem;
  font-size: 1rem;
  color: #fff;
  transition: var(--transition);
}

.form-group input:focus, 
.form-group textarea:focus {
  outline: none;
  border-color: #fff;
  background: rgba(255, 255, 255, 0.08);
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: #444;
}

.contact-form button {
  margin-top: var(--spacing-lg);
  width: 100%;
  background: #fff;
  color: #000;
  border: none;
  padding: 1.2rem;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
}

.contact-form button:hover {
  background: #000;
  color: #fff;
  box-shadow: 0 0 30px rgba(255, 255, 255, 0.2);
}

footer {
  padding: var(--spacing-xl) 0;
  border-top: 1px solid var(--border-color);
  text-align: center;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-md);
}

.social-links a:hover {
  color: var(--accent-color);
}

button:focus-visible, 
a:focus-visible, 
input:focus-visible, 
textarea:focus-visible {
  outline: 2px solid var(--accent-color);
  outline-offset: 4px;
}

@media (max-width: 1024px) {
  .projects-grid {
    grid-template-columns: 1fr;
  }
  
  .arc-container {
    width: 60vh;
    height: 60vh;
    right: -20%;
  }
}

@media (max-width: 768px) {
  :root {
    --spacing-xl: 4rem;
  }

  .about-content {
    gap: var(--spacing-lg);
  }
  
  .nav-links {
    display: none;
  }
  
  .hero {
    justify-content: center;
    text-align: center;
    padding-top: 120px;
  }

  .logo img {
    height: 60px;
  }

  .hero h1 {
    font-size: clamp(3rem, 15vw, 5rem);
    line-height: 1;
  }

  .hero p {
    margin: 0 auto var(--spacing-lg);
  }

  .hero-content {
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .arc-container {
    width: 50vh;
    height: 50vh;
    right: 50%;
    transform: translate(50%, -50%) rotate(-15deg);
    opacity: 0.3;
  }

  .project-content h3 {
    font-size: 1.8rem;
  }

  .about-content h2 {
    font-size: 2.5rem;
  }

  .contact-form {
    padding: var(--spacing-lg);
  }
}