/* style.css — Noval Prakoso | Data Engineer Portfolio */

:root {
  /* Colours */
  --color-bg:     #0f172a;   
  --color-bg-alt: #1e293b;   
  --color-text:   #e2e8f0;   
  --color-accent: #38bdf8;   

  /* Typography */
  --font-heading: 'Inter', system-ui, sans-serif;
  --font-body:    'Source Sans 3', system-ui, sans-serif;

  /* Spacing scale (8px base) */
  --space-1:  8px;
  --space-2:  16px;
  --space-3:  24px;
  --space-4:  32px;
  --space-6:  48px;
  --space-8:  64px;
  --space-12: 96px;

  /* Layout */
  --max-width:     1100px;
  --border-radius: 8px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background-color: var(--color-bg);
}

/* ============================================================
   Header & Navigation
   ============================================================ */
header {
  position: sticky;
  top: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-2) var(--space-4);
  background-color: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-bg-alt);
  z-index: 100;
}

.site-name {
  font-family: var(--font-heading);
  font-weight: 700;
}

.nav-list {
  display: flex;
  gap: var(--space-3);
  list-style: none;
}

.nav-list a {
  color: var(--color-accent);
  text-decoration: none;
  padding: var(--space-1) var(--space-2);
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.nav-list a:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ============================================================
   Hero Section
   ============================================================ */
#hero {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: var(--space-8) var(--space-4);
}

#hero h1 {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--space-2);
}

.hero-title {
  font-size: 1.25rem;
  color: var(--color-accent);
  margin-bottom: var(--space-2);
}

.hero-tagline {
  font-size: 1rem;
  margin-bottom: var(--space-4);
  max-width: 480px;
}

.btn {
  display: inline-block;
  background-color: var(--color-accent);
  color: #ffffff;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--border-radius);
  text-decoration: none;
  font-family: var(--font-heading);
  font-weight: 600;
  min-height: 44px;
  line-height: 44px;
}

.btn:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ============================================================
   About Section
   ============================================================ */
#about {
  background-color: var(--color-bg-alt);
  padding: var(--space-8) var(--space-4);
}

#about h2,
#about p {
  max-width: var(--max-width);
  margin-inline: auto;
}

#about h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  margin-bottom: var(--space-3);
}

#about p {
  font-size: 1rem;
  line-height: 1.7;
}

/* ============================================================
   Projects Section
   ============================================================ */
#projects {
  padding: var(--space-8) var(--space-4);
}

#projects h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  margin-bottom: var(--space-4);
  max-width: var(--max-width);
  margin-inline: auto;
}

.projects-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
  max-width: var(--max-width);
  margin-inline: auto;
}

.project-card {
  background-color: var(--color-bg-alt);
  border-radius: var(--border-radius);
  padding: var(--space-4);
  border: 1px solid rgba(255,255,255,0.05);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 25px rgba(0,0,0,0.4);
}

.project-title {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.project-description {
  font-size: 0.95rem;
  margin-bottom: var(--space-3);
  line-height: 1.6;
}

.project-tech-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  list-style: none;
  margin-bottom: var(--space-3);
}

.project-tech-list li {
  border: 1px solid var(--color-accent);
  background-color: transparent;
  border-radius: 20px;
  padding: 4px 12px;
  font-size: 0.85rem;
  color: var(--color-accent);
}

.project-link {
  color: var(--color-accent);
  font-weight: 600;
  text-decoration: none;
}

.project-link:hover {
  text-decoration: underline;
}

/* ============================================================
   Skills Section
   ============================================================ */
#skills {
  background-color: var(--color-bg-alt);
  padding: var(--space-8) var(--space-4);
}

#skills h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  margin-bottom: var(--space-4);
  max-width: var(--max-width);
  margin-inline: auto;
}

.skills-categories {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  max-width: var(--max-width);
  margin-inline: auto;
}

.skills-categories h3 {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: var(--space-1);
}

.skills-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.skills-list li {
  font-size: 0.95rem;
}

/* ============================================================
   Contact Section
   ============================================================ */
#contact {
  padding: var(--space-8) var(--space-4);
}

#contact h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  margin-bottom: var(--space-4);
  max-width: var(--max-width);
  margin-inline: auto;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-width: var(--max-width);
  margin-inline: auto;
}

.contact-links a {
  color: var(--color-accent);
  text-decoration: none;
  font-size: 1rem;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.contact-links a:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ============================================================
   Footer
   ============================================================ */
footer {
  background-color: var(--color-bg-alt);
  color: #e2e8f0;
  text-align: center;
  padding: var(--space-4);
  font-size: 0.875rem;
}

/* ============================================================
   Responsive — Tablet (≥ 768px)
   ============================================================ */
@media (min-width: 768px) {
  .projects-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  #hero {
    flex-direction: row;
    text-align: left;
    justify-content: center;
    gap: var(--space-8);
  }

  .skills-categories {
    flex-direction: row;
    flex-wrap: wrap;
  }
}

/* ============================================================
   Responsive — Desktop (≥ 1024px)
   ============================================================ */
@media (min-width: 1024px) {
  #hero h1 {
    font-size: 3rem;
  }

  .hero-title {
    font-size: 1.5rem;
  }

  header {
    padding: var(--space-2) var(--space-8);
  }
}