Clean up CSS, minor design changes

1 files changed, 5 insertions, 5 deletions

diff --git a/content/know/concept/feynman-diagram/index.pdc b/content/know/concept/feynman-diagram/index.pdc
index 600be61..98ed668 100644
--- a/content/know/concept/feynman-diagram/index.pdc
+++ b/content/know/concept/feynman-diagram/index.pdc
@@ -43,7 +43,7 @@ and $\mathcal{T}\{\}$ denote the
 [time-ordered product](/know/concept/time-ordered-product/):
 
 <a href="freegf.png">
-<img src="freegf.png" style="width:60%;display:block;margin:auto;">
+<img src="freegf.png" style="width:60%">
 </a>
 $$\begin{aligned}
     = i \hbar G_{s_2 s_1}^0(\vb{r}_2, t_2; \vb{r}_1, t_1)
@@ -64,7 +64,7 @@ a causal Green's function $G$ for the entire Hamiltonian $\hat{H}$,
 where the subscript $H$ refers to the [Heisenberg picture](/know/concept/heisenberg-picture/):
 
 <a href="fullgf.png">
-<img src="fullgf.png" style="width:60%;display:block;margin:auto;">
+<img src="fullgf.png" style="width:60%">
 </a>
 $$\begin{aligned}
     = i \hbar G_{s_2 s_1}(\vb{r}_2, t_2; \vb{r}_1, t_1)
@@ -79,7 +79,7 @@ hence it starts and ends at the same time,
 and no arrow is drawn:
 
 <a href="interaction.png">
-<img src="interaction.png" style="width:60%;display:block;margin:auto;">
+<img src="interaction.png" style="width:60%">
 </a>
 $$\begin{aligned}
     = \frac{1}{i \hbar} W_{s_2 s_1}(\vb{r}_2, t_2; \vb{r}_1, t_1)
@@ -102,7 +102,7 @@ One-body (time-dependent) operators $\hat{V}$ in $\hat{H}_1$
 are instead represented by a special vertex:
 
 <a href="perturbation.png">
-<img src="perturbation.png" style="width:35%;display:block;margin:auto;">
+<img src="perturbation.png" style="width:35%">
 </a>
 $$\begin{aligned}
     = \frac{1}{i \hbar} V_s(\vb{r}, t)
@@ -179,7 +179,7 @@ Consider the following diagram and the resulting expression,
 where $\tilde{\vb{r}} = (\vb{r}, t)$, and $\tilde{\vb{k}} = (\vb{k}, \omega)$:
 
 <a href="conservation.png">
-<img src="conservation.png" style="width:40%;display:block;margin:auto;">
+<img src="conservation.png" style="width:40%">
 </a>
 $$\begin{aligned}
     &= (i \hbar)^3 \sum_{s s'} \!\!\iint \dd{\tilde{\vb{r}}} \dd{\tilde{\vb{r}}'}