Tu n’est pas en face de la documentation…
En clair, tu n’indique pas où se trouve ton champ personnalisé temp
représentant la température…
Mets toi en face de la documentation et tout va rentrer dans l’ordre
- grid-template-areas: '"i temp" "n n" "cpu cpu" "ram ram" "sd sd"'
Pour la petit explication en français :
- ``grid-template-areas : définition de la position des champs (indique le nombre de colonne et le nombre de ligne
Ce qui pour ton icone pour donner un autre exemple :

type: 'custom:button-card'
entity: mailbox.demomailbox
icon: 'mdi:raspberry-pi'
name: Pi4 8Go
styles:
card:
- height: 130px
- width: 120px
- background-color: '#243665'
- border-radius: 20% 5px
- padding: 10%
- color: '#eee'
- font-size: 12px
- font-weight: bold
grid:
- grid-template-areas: ' "n n" "i temp" "cpu cpu" "ram ram" "sd sd"'
- grid-template-columns: 1fr 1fr
- grid-template-rows: 1fr 3fr 1fr 1fr 1fr
name:
- font-weight: bold
- font-size: 13px
- align-self: middle
- justify-self: start
- padding-bottom: 4px
- color: var(--text-color)
img_cell:
- justify-content: start
- align-items: start
- margin: none
icon:
- color: |
[[[
if (entity.state < 60) return '#eee';
if (entity.state >= 60 && entity.state < 80) return 'orange';
else return 'red';
]]]
- width: 100%
- margin-top: '-10%'
- margin-left: '-10%'
- animation: |
[[[ if (entity.state == 'on') return 'blink 2s ease infinite'; ]]]
custom_fields:
temp:
- justify-self: start
- transform: scale(1.5)
- margin-left: 10px
- margin-top: '-10px'
cpu:
- padding-bottom: 2px
- align-self: middle
- margin-left: '-5px'
- justify-self: start
ram:
- padding-bottom: 2px
- margin-left: '-5px'
- align-self: middle
- justify-self: end
- '--text-color-sensor': '[[[ if (states["mailbox.demomailbox"].state > 80) return "red"; ]]]'
sd:
- align-self: middle
- margin-left: '-5px'
- justify-self: start
- '--text-color-sensor': '[[[ if (states["mailbox.demomailbox"].state > 80) return "red"; ]]]'
custom_fields:
temp: |
[[[
return `<ha-icon
icon="mdi:thermometer"
style="width: 12px; height: 12px; color: CCF381;">
</ha-icon><span>${entity.state}°C</span>`
]]]
cpu: |
[[[
return `<ha-icon
icon="mdi:server"
style="width: 12px; height: 12px;">
</ha-icon><span>CPU: <span style="color: var(--text-color-sensor);">${states['mailbox.demomailbox'].state}%</span></span>`
]]]
ram: |
[[[
return `<ha-icon
icon="mdi:memory"
style="width: 12px; height: 12px;">
</ha-icon><span>RAM: <span style="color: var(--text-color-sensor);">${states['mailbox.demomailbox'].state}%</span></span>`
]]]
sd: |
[[[
return `<ha-icon
icon="mdi:harddisk"
style="width: 12px; height: 12px;">
</ha-icon><span>SD: <span style="color: var(--text-color-sensor);">${states['mailbox.demomailbox'].state}%</span></span>`
]]]