:root {
  --font-sans: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --radius: 12px;
  --transition-fast: 150ms ease-out;
  --shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.08);
}

body.theme-light {
  --bg: #f5f5f7;
  --bg-elevated: #ffffff;
  --fg: #111827;
  --fg-muted: #6b7280;
  --border-subtle: #e5e7eb;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.08);
}

body.theme-dark {
  --bg: #020617;
  --bg-elevated: #020617;
  --fg: #e5e7eb;
  --fg-muted: #9ca3af;
  --border-subtle: #111827;
  --accent: #38bdf8;
  --accent-soft: rgba(56, 189, 248, 0.1);
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--fg);
  transition: background var(--transition-fast), color var(--transition-fast);
  -webkit-font-smoothing: antialiased;
}

.card {
  background: var(--bg-elevated);
  border-radius: var(--radius);
  padding: 20px;
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-soft);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), transform var(--transition-fast);
}

.card:hover {
  border-color: var(--accent);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.12);
  transform: translateY(-2px);
}

.card ul {
  list-style: none;
  padding-left: 0;
  margin: 0 0 12px;
}

.card li {
  margin-bottom: 8px;
  color: var(--fg);
}

.card a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--transition-fast), text-decoration-color var(--transition-fast);
}

.card a:hover {
  text-decoration: underline;
  text-underline-offset: 2px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  background: linear-gradient(135deg, var(--accent), #4ade80);
  color: #ffffff;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  cursor: pointer;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.14);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), filter var(--transition-fast);
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.18);
  filter: brightness(1.03);
}

.btn:active {
  transform: translateY(0);
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.16);
  filter: brightness(0.98);
}

.btn-panel {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  color: #eaf2ff;
}

.btn-panel:hover {
  filter: brightness(1.05);
}

.btn-panel:active {
  filter: brightness(0.97);
}

input[type="text"],
input[type="email"],
input[type="password"],
select {
  width: 100%;
  padding: 10px 12px;
  border-radius: 999px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
  color: var(--fg);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast);
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus,
select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

::placeholder {
  color: var(--fg-muted);
}

.small-text {
  color: var(--fg-muted);
  font-size: 0.9rem;
}