/* ============================================================
   Charles Joshua P. Dela Austria - Personal Website
   Shared CSS - Color Palette, Theme & Layout
   Palette: #EEE0CB cream | #D9D1D9 lavender | #C4C2E5 periwinkle
            #B0B2EF deeper lavender | #9DA1F9 lavender-blue
   ============================================================ */

/* ---------- Color palette as CSS variables ---------- */
:root {
  /* Palette (light mode defaults) */
  --cream: #EEE0CB;
  --lavender: #D9D1D9;
  --periwinkle: #C4C2E5;
  --lavender-deep: #B0B2EF;
  --lavender-blue: #9DA1F9;

  /* Semantic tokens — LIGHT mode */
  --bg: var(--cream);
  --bg-alt: #FFFFFF;
  --bg-card: #FFFFFF;
  --surface: var(--lavender);
  --text: #2B2A3A;
  --text-muted: #5E5A6E;
  --heading: #1E1D2E;
  --accent: var(--lavender-blue);
  --accent-soft: var(--periwinkle);
  --accent-deep: #6E73E0;
  --border: #D9D1D9;
  --shadow: rgba(110, 115, 224, 0.12);
  --nav-bg: rgba(238, 224, 203, 0.85);
  --hero-grad: linear-gradient(135deg, #C4C2E5 0%, #9DA1F9 100%);
}

/* ---------- Dark mode tokens ---------- */
[data-theme="dark"] {
  --bg: #15131F;
  --bg-alt: #1E1B2B;
  --bg-card: #23203A;
  --surface: #2A2742;
  --text: #E8E6F5;
  --text-muted: #A7A3C0;
  --heading: #FFFFFF;
  --accent: #9DA1F9;
  --accent-soft: #B0B2EF;
  --accent-deep: #C4C2E5;
  --border: #353150;
  --shadow: rgba(0, 0, 0, 0.40);
  --nav-bg: rgba(21, 19, 31, 0.85);
  --hero-grad: linear-gradient(135deg, #353150 0%, #6E73E0 100%);
}

/* ---------- Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  transition: background 0.4s ease, color 0.4s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4 {
  color: var(--heading);
  font-weight: 700;
  line-height: 1.2;
}

a { color: var(--accent-deep); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent); }

/* ---------- Layout helpers ---------- */
.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

main {
  flex: 1 0 auto;
  padding-top: 90px; /* offset for fixed navbar */
}

.section { padding: 4.5rem 0; }
.section-alt { background: var(--bg-alt); }

.section-title {
  font-size: 2.1rem;
  text-align: center;
  margin-bottom: 0.5rem;
}
.section-subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 3rem;
  font-size: 1.05rem;
}
.section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 4px;
  border-radius: 4px;
  background: var(--hero-grad);
  margin: 0.8rem auto 0;
}

/* ---------- Navbar ---------- */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background 0.4s ease;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}
.nav-brand {
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--heading);
  letter-spacing: -0.02em;
}
.nav-brand span { color: var(--accent-deep); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  list-style: none;
}
.nav-links a {
  color: var(--text);
  padding: 0.5rem 0.85rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
}
.nav-links a:hover { background: var(--surface); color: var(--heading); }
.nav-links a.active { color: var(--accent-deep); font-weight: 600; }

/* Dark mode toggle */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px; height: 42px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.15rem;
  color: var(--heading);
  margin-left: 0.75rem;
  transition: transform 0.3s, background 0.2s;
}
.theme-toggle:hover { transform: rotate(20deg) scale(1.08); }
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: inline; }
[data-theme="dark"] .theme-toggle .icon-sun { display: inline; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* Hamburger (mobile) */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none; border: none; cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  width: 24px; height: 2px; background: var(--heading);
  border-radius: 2px; transition: 0.3s;
}

/* ---------- Footer ---------- */
.footer {
  flex-shrink: 0;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 2.5rem 0 1.5rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}
.footer-social { display: flex; justify-content: center; gap: 1rem; margin-bottom: 1rem; }
.footer-social a {
  display: inline-flex; align-items: center; justify-content: center;
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--surface); color: var(--heading);
  transition: background 0.2s, transform 0.2s;
}
.footer-social a:hover { background: var(--accent); color: #fff; transform: translateY(-3px); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.8rem 1.6rem;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.98rem;
  cursor: pointer;
  border: none;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
}
.btn-primary { background: var(--hero-grad); color: #fff; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 20px var(--shadow); color: #fff; }
.btn-outline {
  background: transparent; color: var(--heading);
  border: 1.5px solid var(--accent-deep);
}
.btn-outline:hover { background: var(--accent-deep); color: #fff; }

/* ---------- Cards ---------- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.75rem;
  box-shadow: 0 4px 16px var(--shadow);
  transition: transform 0.25s, box-shadow 0.25s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 10px 30px var(--shadow); }

.grid { display: grid; gap: 1.5rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ---------- Badges / pills ---------- */
.badge {
  display: inline-block;
  padding: 0.35rem 0.85rem;
  border-radius: 50px;
  background: var(--surface);
  color: var(--heading);
  font-size: 0.82rem;
  font-weight: 500;
  border: 1px solid var(--border);
}

/* ---------- Utility ---------- */
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.lead { font-size: 1.12rem; color: var(--text-muted); }
.fade-in { opacity: 0; transform: translateY(20px); transition: opacity 0.6s, transform 0.6s; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ---------- Page hero (inner pages) ---------- */
.page-hero {
  background: var(--hero-grad);
  padding: 3.5rem 0 3rem;
  text-align: center;
  color: #fff;
  margin-bottom: 0;
}
.page-hero h1 { color: #fff; font-size: 2.6rem; }
.page-hero p { color: rgba(255,255,255,0.9); max-width: 640px; margin: 0.5rem auto 0; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: 70px; right: 0;
    flex-direction: column;
    align-items: stretch;
    background: var(--bg-card);
    width: 240px;
    height: calc(100vh - 70px);
    padding: 1rem;
    gap: 0.25rem;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    border-left: 1px solid var(--border);
    box-shadow: -4px 0 20px var(--shadow);
  }
  .nav-links.open { transform: translateX(0); }
  .nav-links a { padding: 0.85rem 1rem; }
  .section-title { font-size: 1.7rem; }
  .page-hero h1 { font-size: 2rem; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}