/* ── FEAT-028: Upgrade Mode Page ─────────────────────────────────────── */
.upgrade-page {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-primary, #1a1a2e);
}
.upgrade-content { text-align: center; padding: 48px 32px; max-width: 480px; }
.upgrade-brand { font-size: 1.4rem; font-weight: 700; color: var(--accent-orange, #f4a724); letter-spacing: 0.05em; margin-bottom: 24px; }
.upgrade-icon { font-size: 3rem; margin-bottom: 20px; }
.upgrade-title { font-size: 1.6rem; font-weight: 600; color: var(--text-primary, #e8eaf0); margin-bottom: 16px; }
.upgrade-msg { font-size: 1rem; color: var(--text-primary, #e8eaf0); margin-bottom: 8px; }
.upgrade-submsg { font-size: 0.95rem; color: var(--text-secondary, #9ea3b0); margin-bottom: 32px; }
.upgrade-contact { font-size: 0.82rem; color: var(--text-secondary, #9ea3b0); border-top: 1px solid rgba(255,255,255,0.08); padding-top: 20px; }

body[data-theme="light"] .upgrade-page { background: #f0f2f5; }
body[data-theme="light"] .upgrade-title { color: #1a1a2e; }
body[data-theme="light"] .upgrade-msg { color: #2c2c3e; }
body[data-theme="light"] .upgrade-contact { border-top-color: rgba(0,0,0,0.1); }