/* ===== THEME VARIABLES ===== */
:root {
  --color-bg: #fafafa;
  --color-bg-elevated: #ffffff;
  --color-bg-subtle: rgba(0, 0, 0, 0.05);
  --color-text-primary: #1a1a1a;
  --color-text-secondary: #555555;
  --color-text-tertiary: #666666;
  --color-text-muted: #888888;
  --color-text-faint: #999999;
  --color-text-ghost: #cccccc;
  --color-accent: #6f4cff;
  --color-accent-hover: #8b6fff;
  --color-accent-bg: rgba(111, 76, 255, 0.08);
  --color-accent-bg-hover: rgba(111, 76, 255, 0.15);
  --color-border: rgba(0, 0, 0, 0.06);
  --color-border-hover: rgba(111, 76, 255, 0.15);
  --color-nav-bg: rgba(250, 250, 250, 0.85);
  --color-nav-border: rgba(0, 0, 0, 0.05);
  --color-nav-shadow: rgba(0, 0, 0, 0.04);
  --color-nav-mobile-bg: rgba(250, 250, 250, 0.98);
  --color-sidebar-border: rgba(0, 0, 0, 0.1);
  --color-sidebar-line: rgba(0, 0, 0, 0.15);
  --color-sidebar-icon: #666666;
  --color-cta-bg: #1a1a1a;
  --color-cta-text: #ffffff;
  --color-cta-hover-bg: transparent;
  --color-cta-hover-text: #1a1a1a;
  --color-cta-border: #1a1a1a;
  --color-shadow: rgba(0, 0, 0, 0.06);
  --blob-1: linear-gradient(135deg, #6f4cff, #4a8eff);
  --blob-2: linear-gradient(135deg, #ff6b9d, #ff9a76);
  --blob-3: linear-gradient(135deg, #a78bfa, #6f4cff);
  --blob-4: linear-gradient(135deg, #ff9a76, #fbc2eb);
  --blob-opacity: 0.35;
  --color-contact-bg: #1a1a1a;
  --color-contact-text: #ffffff;
  --color-contact-muted: rgba(255, 255, 255, 0.6);
  --color-contact-faint: rgba(255, 255, 255, 0.3);
  --color-contact-card-bg: rgba(255, 255, 255, 0.05);
  --color-contact-card-border: rgba(255, 255, 255, 0.08);
  --color-contact-card-hover-bg: rgba(255, 255, 255, 0.1);
  --color-contact-card-hover-border: rgba(111, 76, 255, 0.4);
  --color-footer-bg: #111111;
  --color-footer-text: rgba(255, 255, 255, 0.3);
  --color-selection-bg: rgba(111, 76, 255, 0.15);
  --color-selection-text: #1a1a1a;
  --hero-photo-gradient: linear-gradient(135deg, #e8e0ff, #fce4ec, #e3f2fd);
  --color-about-accent-bg: #1a1a1a;
  --theme-transition: 0.3s ease;
}

html.dark {
  --color-bg: #0f0f11;
  --color-bg-elevated: #111116;
  --color-bg-subtle: rgba(255, 255, 255, 0.05);
  --color-text-primary: #e8e8ec;
  --color-text-secondary: #a0a0a8;
  --color-text-tertiary: #8a8a94;
  --color-text-muted: #6a6a74;
  --color-text-faint: #585860;
  --color-text-ghost: #3a3a42;
  --color-accent: #8b6fff;
  --color-accent-hover: #a78bfa;
  --color-accent-bg: rgba(139, 111, 255, 0.12);
  --color-accent-bg-hover: rgba(139, 111, 255, 0.20);
  --color-border: rgba(255, 255, 255, 0.08);
  --color-border-hover: rgba(139, 111, 255, 0.25);
  --color-nav-bg: rgba(15, 15, 17, 0.88);
  --color-nav-border: rgba(255, 255, 255, 0.06);
  --color-nav-shadow: rgba(0, 0, 0, 0.2);
  --color-nav-mobile-bg: rgba(15, 15, 17, 0.98);
  --color-sidebar-border: rgba(255, 255, 255, 0.1);
  --color-sidebar-line: rgba(255, 255, 255, 0.12);
  --color-sidebar-icon: #8a8a94;
  --color-cta-bg: #e8e8ec;
  --color-cta-text: #0f0f11;
  --color-cta-hover-bg: transparent;
  --color-cta-hover-text: #e8e8ec;
  --color-cta-border: #e8e8ec;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --blob-1: linear-gradient(135deg, #6f4cff, #4a8eff);
  --blob-2: linear-gradient(135deg, #ff6b9d, #ff9a76);
  --blob-3: linear-gradient(135deg, #a78bfa, #6f4cff);
  --blob-4: linear-gradient(135deg, #ff9a76, #fbc2eb);
  --blob-opacity: 0.30;
  --color-contact-bg: #161618;
  --color-contact-text: #e8e8ec;
  --color-contact-muted: rgba(255, 255, 255, 0.5);
  --color-contact-faint: rgba(255, 255, 255, 0.25);
  --color-contact-card-bg: rgba(255, 255, 255, 0.04);
  --color-contact-card-border: rgba(255, 255, 255, 0.06);
  --color-contact-card-hover-bg: rgba(255, 255, 255, 0.08);
  --color-contact-card-hover-border: rgba(139, 111, 255, 0.4);
  --color-footer-bg: #0a0a0c;
  --color-footer-text: rgba(255, 255, 255, 0.25);
  --color-selection-bg: rgba(139, 111, 255, 0.25);
  --color-selection-text: #e8e8ec;
  --hero-photo-gradient: linear-gradient(135deg, #2a2440, #2a1f28, #1f2830);
  --color-about-accent-bg: #161618;
}

/* ===== RESET & BASE ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--color-text-primary);
  background: var(--color-bg);
  line-height: 1.7;
  font-weight: 400;
  overflow-x: hidden;
  position: relative;
  transition: background-color var(--theme-transition), color var(--theme-transition);
}

::selection {
  background: var(--color-selection-bg);
  color: var(--color-selection-text);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.3s ease, opacity 0.3s ease;
}

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

/* ===== TYPOGRAPHY ===== */
h1, h2, h3 {
  font-family: 'DM Serif Display', Georgia, serif;
  font-weight: 400;
  line-height: 1.15;
}

/* ===== GRADIENT BLOBS ===== */
.blob {
  position: fixed;
  border-radius: 50%;
  filter: blur(100px);
  opacity: var(--blob-opacity);
  pointer-events: none;
  z-index: 0;
  will-change: transform;
  transition: opacity var(--theme-transition);
}

.blob-1 {
  width: 600px;
  height: 600px;
  background: var(--blob-1);
  top: -100px;
  right: -150px;
  animation: blobFloat1 20s ease-in-out infinite;
}

.blob-2 {
  width: 500px;
  height: 500px;
  background: var(--blob-2);
  bottom: 10%;
  left: -200px;
  animation: blobFloat2 25s ease-in-out infinite;
}

.blob-3 {
  width: 400px;
  height: 400px;
  background: var(--blob-3);
  top: 50%;
  right: 10%;
  animation: blobFloat3 22s ease-in-out infinite;
}

.blob-4 {
  width: 350px;
  height: 350px;
  background: var(--blob-4);
  top: 70%;
  left: 20%;
  animation: blobFloat1 18s ease-in-out infinite reverse;
}

@keyframes blobFloat1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(30px, -40px) scale(1.05); }
  50% { transform: translate(-20px, 20px) scale(0.95); }
  75% { transform: translate(15px, 35px) scale(1.02); }
}

@keyframes blobFloat2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, -30px) scale(1.08); }
  66% { transform: translate(-30px, 40px) scale(0.96); }
}

@keyframes blobFloat3 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(-25px, 30px) scale(1.04); }
  50% { transform: translate(35px, -20px) scale(0.97); }
  75% { transform: translate(-15px, -35px) scale(1.06); }
}

/* ===== LAYOUT ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
  position: relative;
  z-index: 1;
}

section {
  padding: 120px 0;
  position: relative;
}

/* ===== NAVIGATION ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 40px;
  background: var(--color-nav-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-nav-border);
  transition: background-color var(--theme-transition), border-color var(--theme-transition), box-shadow 0.3s ease;
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.nav-logo {
  font-family: 'DM Serif Display', Georgia, serif;
  font-size: 1.4rem;
  letter-spacing: -0.02em;
  color: var(--color-text-primary);
}

.nav-links {
  display: flex;
  gap: 48px;
  list-style: none;
  align-items: center;
}

.nav-link {
  text-align: center;
  cursor: pointer;
  position: relative;
}

.nav-link a {
  display: block;
}

.nav-link-title {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  color: var(--color-text-primary);
  transition: color 0.3s ease;
}

.nav-link-desc {
  font-size: 0.7rem;
  color: var(--color-text-faint);
  margin-top: 2px;
  font-weight: 400;
  letter-spacing: 0.01em;
  transition: color 0.3s ease;
}

.nav-link:hover .nav-link-title,
.nav-link.active .nav-link-title {
  color: var(--color-accent);
}

.nav-link:hover .nav-link-desc,
.nav-link.active .nav-link-desc {
  color: var(--color-accent);
}

/* Featured nav link (Build Log) */
.nav-link--featured {
  display: flex;
  align-items: center;
}

.nav-link--featured a {
  display: flex;
  align-items: center;
  background: var(--color-accent-bg);
  padding: 6px 16px;
  border-radius: 100px;
  transition: background 0.3s ease;
}

.nav-link--featured .nav-link-title {
  color: var(--color-accent);
}

.nav-link--featured:hover a {
  background: var(--color-accent);
}

.nav-link--featured:hover .nav-link-title {
  color: #fff;
}

/* Mobile menu */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
  background: none;
  border: none;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text-primary);
  transition: all 0.3s ease;
  display: block;
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ===== THEME TOGGLE ===== */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  background: var(--color-bg-elevated);
  cursor: pointer;
  transition: all 0.3s ease;
  flex-shrink: 0;
}

.theme-toggle:hover {
  border-color: var(--color-accent);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
  color: var(--color-text-secondary);
  transition: color 0.3s ease, transform 0.4s ease;
}

.theme-toggle:hover svg {
  color: var(--color-accent);
}

/* Show moon in light mode (click to go dark), sun in dark mode (click to go light) */
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }

html.dark .theme-toggle .icon-sun { display: block; }
html.dark .theme-toggle .icon-moon { display: none; }

.theme-toggle.animating svg {
  transform: rotate(360deg);
}

/* ===== SOCIAL SIDEBAR ===== */
.social-sidebar {
  position: fixed;
  left: max(12px, calc((100vw - 1200px) / 2 - 60px));
  top: 50%;
  transform: translateY(-50%);
  z-index: 50;
  display: flex;
  flex-direction: column;
  gap: 24px;
  align-items: center;
}

.social-sidebar::before {
  content: '';
  width: 1px;
  height: 60px;
  background: var(--color-sidebar-line);
  margin-bottom: 8px;
}

.social-sidebar::after {
  content: '';
  width: 1px;
  height: 60px;
  background: var(--color-sidebar-line);
  margin-top: 8px;
}

.social-sidebar a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid var(--color-sidebar-border);
  transition: all 0.3s ease;
  color: var(--color-sidebar-icon);
}

.social-sidebar a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-2px);
}

.social-sidebar svg {
  width: 18px;
  height: 18px;
}

/* ===== FOOTER ===== */
.footer {
  padding: 40px 0;
  background: var(--color-footer-bg);
  color: var(--color-footer-text);
  font-size: 0.85rem;
  text-align: center;
  letter-spacing: 0.02em;
}

/* ===== SMOOTH THEME TRANSITIONS ===== */
body,
.nav,
.metric,
.ai-card,
.appearance-item,
.build-entry,
.filter-btn,
.contact,
.footer,
.social-sidebar a,
.theme-toggle {
  transition: background-color var(--theme-transition),
              color var(--theme-transition),
              border-color var(--theme-transition),
              box-shadow var(--theme-transition);
}

/* ===== PRINT STYLES ===== */
@media print {
  :root {
    --color-bg: #ffffff;
    --color-bg-elevated: #ffffff;
    --color-text-primary: #000000;
    --color-text-secondary: #333333;
    --color-text-tertiary: #444444;
    --color-accent: #6f4cff;
    --color-border: #cccccc;
    --blob-opacity: 0;
  }
  .theme-toggle,
  .blob,
  .social-sidebar { display: none !important; }
}

/* ===== RESPONSIVE ===== */
@media (max-width: 1440px) and (min-width: 1025px) {
  .container { padding: 0 40px 0 72px; }
  .nav { padding: 0 40px 0 72px; }
}

@media (max-width: 1024px) {
  .container { padding: 0 32px; }
  .nav { padding: 0 32px; }
  .social-sidebar { display: none; }
}

@media (max-width: 768px) {
  .container { padding: 0 24px; }
  .nav { padding: 0 24px; }

  .nav-links {
    display: none;
    position: fixed;
    top: 80px;
    left: 0;
    right: 0;
    background: var(--color-nav-mobile-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 32px 24px;
    gap: 24px;
    border-bottom: 1px solid var(--color-nav-border);
  }

  .nav-links.open { display: flex; }

  .nav-link { text-align: left; }

  .nav-link--featured a {
    padding: 10px 16px;
    border-radius: 8px;
  }

  .nav-toggle { display: flex; }

  .theme-toggle {
    margin-left: auto;
    margin-right: 12px;
    order: -1;
  }

  section { padding: 80px 0; }

  .blob-1 { width: 300px; height: 300px; }
  .blob-2 { width: 250px; height: 250px; }
  .blob-3 { width: 200px; height: 200px; }
  .blob-4 { display: none; }
}