:root {
  --bg-main: #090d16;
  --bg-card: rgba(18, 24, 38, 0.75);
  --bg-card-hover: rgba(26, 34, 52, 0.92);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(168, 85, 247, 0.4);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent-purple: #a855f7;
  --accent-amber: #f59e0b;
  --accent-blue: #38bdf8;
  --accent-emerald: #10b981;
  --radius-lg: 18px;
  --radius-md: 10px;
  --radius-full: 9999px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  --shadow-sm: 0 4px 14px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 12px 30px -8px rgba(168, 85, 247, 0.25);
  --chip-bg: rgba(255, 255, 255, 0.05);
  --chip-border: rgba(255, 255, 255, 0.08);
  --hero-title-grad: linear-gradient(90deg, #f8fafc 0%, #cbd5e1 100%);
  --grad-1: rgba(168, 85, 247, 0.12);
  --grad-2: rgba(56, 189, 248, 0.1);
  --grad-3: rgba(245, 158, 11, 0.08);
}

html.light {
  --bg-main: #f8fafc;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: rgba(255, 255, 255, 0.98);
  --border-color: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(147, 51, 234, 0.45);
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --accent-purple: #9333ea;
  --accent-amber: #d97706;
  --accent-blue: #0284c7;
  --accent-emerald: #059669;
  --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-glow: 0 12px 28px -8px rgba(147, 51, 234, 0.18);
  --chip-bg: rgba(0, 0, 0, 0.04);
  --chip-border: rgba(0, 0, 0, 0.08);
  --hero-title-grad: linear-gradient(90deg, #0f172a 0%, #334155 100%);
  --grad-1: rgba(168, 85, 247, 0.07);
  --grad-2: rgba(56, 189, 248, 0.07);
  --grad-3: rgba(245, 158, 11, 0.06);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  transition: background-color 0.25s ease, border-color 0.25s ease, color 0.25s ease;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-image: 
    radial-gradient(circle at 15% 15%, var(--grad-1) 0%, transparent 40%),
    radial-gradient(circle at 85% 60%, var(--grad-2) 0%, transparent 40%),
    radial-gradient(circle at 50% 95%, var(--grad-3) 0%, transparent 40%);
  background-attachment: fixed;
}

.container {
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 40px 20px 60px;
  flex: 1;
}

/* Header & Profile */
header {
  margin-bottom: 36px;
  position: relative;
}

.hero-profile {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: relative;
}

.hero-profile:hover {
  border-color: rgba(168, 85, 247, 0.25);
}

/* Theme Toggle Button */
.theme-toggle-btn {
  position: absolute;
  top: 24px;
  right: 24px;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
  background: var(--chip-bg);
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: var(--shadow-sm);
}

.theme-toggle-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: rotate(15deg) scale(1.08);
  color: var(--accent-purple);
}

.theme-toggle-btn:focus-visible {
  outline: 2px solid var(--accent-purple);
  outline-offset: 2px;
}

html.light .icon-moon {
  display: block;
}

html.light .icon-sun {
  display: none;
}

html:not(.light) .icon-moon {
  display: none;
}

html:not(.light) .icon-sun {
  display: block;
}

.profile-top {
  display: flex;
  align-items: center;
  gap: 20px;
  padding-right: 50px;
}

.avatar {
  width: 72px;
  height: 72px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #a855f7 0%, #38bdf8 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 28px;
  color: #fff;
  box-shadow: 0 6px 20px rgba(168, 85, 247, 0.35);
  flex-shrink: 0;
}

.profile-info h1 {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--hero-title-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.profile-role {
  color: var(--accent-purple);
  font-weight: 600;
  font-size: 15px;
  margin-top: 2px;
}

.profile-bio {
  color: var(--text-secondary);
  font-size: 15.5px;
  line-height: 1.65;
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.tag {
  background: var(--chip-bg);
  border: 1px solid var(--chip-border);
  padding: 5px 12px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  letter-spacing: 0.02em;
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border-color);
}

.btn-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: var(--radius-md);
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  color: var(--text-primary);
  background: var(--chip-bg);
  border: 1px solid var(--border-color);
}

.btn-link:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.btn-link.primary {
  background: linear-gradient(135deg, #a855f7 0%, #7e22ce 100%);
  color: #fff;
  border: none;
  box-shadow: 0 4px 14px rgba(168, 85, 247, 0.3);
}

.btn-link.primary:hover {
  background: linear-gradient(135deg, #b86bfa 0%, #9333ea 100%);
  box-shadow: 0 6px 18px rgba(168, 85, 247, 0.45);
}

/* Projects Section */
.section-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title::after {
  content: "";
  height: 1px;
  flex: 1;
  background: linear-gradient(90deg, var(--border-color) 0%, transparent 100%);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(310px, 1fr));
  gap: 22px;
}

.project-card {
  background: var(--bg-card);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  text-decoration: none;
  color: inherit;
  transition: all 0.28s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.project-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  opacity: 0;
  transition: opacity 0.25s ease;
}

.project-card.calc::before {
  background: linear-gradient(90deg, #f59e0b, #fbbf24);
}

.project-card.grid::before {
  background: linear-gradient(90deg, #38bdf8, #818cf8);
}

.project-card.cv::before {
  background: linear-gradient(90deg, #a855f7, #ec4899);
}

.project-card:hover {
  transform: translateY(-4px);
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-glow);
}

.project-card:hover::before {
  opacity: 1;
}

.card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.card-icon {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.project-card.calc .card-icon {
  background: rgba(245, 158, 11, 0.12);
  border: 1px solid rgba(245, 158, 11, 0.25);
  color: var(--accent-amber);
}

.project-card.grid .card-icon {
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.25);
  color: var(--accent-blue);
}

.project-card.cv .card-icon {
  background: rgba(168, 85, 247, 0.12);
  border: 1px solid rgba(168, 85, 247, 0.25);
  color: var(--accent-purple);
}

.badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 3px 9px;
  border-radius: 6px;
  letter-spacing: 0.04em;
}

.badge-live {
  background: rgba(16, 185, 129, 0.14);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.badge-lib {
  background: rgba(56, 189, 248, 0.14);
  color: var(--accent-blue);
  border: 1px solid rgba(56, 189, 248, 0.3);
}

.badge-cv {
  background: rgba(168, 85, 247, 0.14);
  color: var(--accent-purple);
  border: 1px solid rgba(168, 85, 247, 0.3);
}

.project-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 3px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.project-domain {
  font-size: 12px;
  color: var(--accent-purple);
  font-weight: 600;
  margin-bottom: 10px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

.project-desc {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 18px;
}

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: auto;
  padding-top: 14px;
  border-top: 1px solid var(--border-color);
}

.tech-chip {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--chip-bg);
  border: 1px solid var(--chip-border);
  padding: 3px 8px;
  border-radius: 5px;
}

.card-footer-action {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text-primary);
  transition: gap 0.2s ease, color 0.2s ease;
}

.project-card:hover .card-footer-action {
  gap: 10px;
  color: var(--accent-purple);
}

/* Footer */
footer {
  text-align: center;
  padding: 24px;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 13px;
}

@media (max-width: 640px) {
  .container {
    padding: 20px 14px 40px;
  }

  .hero-profile {
    padding: 22px 18px;
  }

  .theme-toggle-btn {
    top: 18px;
    right: 18px;
    width: 38px;
    height: 38px;
  }

  .profile-top {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
    padding-right: 40px;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }
}