/* A quiet frame for vivid subjects. Local tokens preserve the user's theme. */
.learning-surface {
 --bg-primary: #101917; --bg-secondary: #192420; --bg-card: #1b2823;
 --text-primary: #f2f2e9; --text-secondary: #b1c0b6; --border-color: #33433b;
 --cyan: #c8eaa2; --nav-bg: #101917f5; --focus-accent: #c8eaa2;
 background: var(--bg-primary); color: var(--text-primary);
}
[data-theme="light"] .learning-surface {
 --bg-primary: #f6f5ef; --bg-secondary: #efeee6; --bg-card: #fffef9;
 --text-primary: #203b31; --text-secondary: #5d6c62; --border-color: #d9dfd4;
 --cyan: #356647; --nav-bg: #f6f5eff5; --focus-accent: #356647;
}
.learning-surface > nav { background: var(--nav-bg); border-bottom: 1px solid var(--border-color); box-shadow: none; }
.learning-surface > nav .container { max-width: 1180px; }
.learning-surface > nav .logo { font-size: 1.4rem; }
.learning-surface > nav .logo-text { letter-spacing: .3px; text-transform: none; background: none; -webkit-text-fill-color: var(--text-primary); }
.learning-surface > nav .nav-links { gap: 26px; }
.learning-surface > nav .nav-links a { font-size: .9rem; }
.learning-surface > nav .theme-toggle { border-color: transparent; background: transparent; padding-inline: 8px; }
.learning-surface > nav .focus-sign-in { color: var(--text-primary); padding: 10px; font-size: .85rem; text-decoration: none; }

@media(max-width:1000px) { .learning-surface > nav .theme-toggle-text { display: none; } }