Margin walkthrough — original silent visual explanation
Synthetic prices and a simplified fixed maintenance rule. No performance evidence.

01 / OPEN THE HEDGE
Spot position
Buy 1 unit at $100
Short future
Sell 1 unit at $100
$20 collateral sits in the short account.
The two accounts cannot transfer cash during this shock.

02 / BOTH MARKS RISE TO $115
Spot position
Marked gain: $15
Short future
Marked loss: $15
Combined trading P&L is zero.
But short-account equity falls from $20 to $5.

03 / CHECK LOCAL MARGIN
Short-account equity
$5 remains
Required equity
$8 in this scenario
The short account has a $3 shortfall.
This simplified scenario triggers liquidation.

04 / CHECK THE WHOLE PATH
Terminal payoff
May converge later
Cash availability
Needed at each venue
A neutral mark does not guarantee survival.
Model transfers, haircuts, margin changes and closeout costs.
