oslo/static/style.css

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background: #aab5a9;
  color: #000;
  font-family: Verdana, Geneva, Tahoma, sans-serif;
  font-size: 12px;
}

a {
  color: #000;
}

a:hover {
  text-decoration: none;
}

.btn {
  cursor: pointer;
  background: #ffffff;
  border: 1px solid #383e37;
  border-radius: 0;
  padding: 0.15em 0.3em;
}

.btn:hover {
  background-color: #f0f0f0;
}

.danger {
  color: #942626;
}

.container {
  margin: auto;
  max-width: 800px;
  padding: 1em;
}

.header {
  align-items: center;
  display: flex;
  justify-content: space-between;
  margin: 1em 0;
}

.header__logo {
  background-color: #ffffff;
  border: 1px solid #383e37;
  font-size: 14px;
  font-style: italic;
  font-weight: bold;
  letter-spacing: 2px;
  padding: 0.25em 0.5em;
  text-decoration: none;
}

.header__logo:hover {
  background-color: #f0f0f0;
}

.form__field {
  margin: 1em 0;
}

.form__label {
  display: block;
  margin-bottom: 0.5em;
}

.form__textarea,
.form__text-field {
  font-family: Verdana, Geneva, Tahoma, sans-serif;
  font-size: 12px;
  padding: 0.25em;
  width: 100%;
}

.form__textarea {
  height: 200px;
  resize: vertical;
}

.post:not(:last-child) {
  margin: 3em 0;
}

.post__heading {
  align-items: center;
  background: white;
  border: 1px solid #383e37;
  display: flex;
  flex-wrap: wrap;
  font-size: 12px;
  font-weight: bold;
  justify-content: space-between;
  margin-bottom: 1em;
  padding: 0.5em;
}

.post__title {
  flex: 1;
  margin-right: 1em;
  min-width: 220px;
}

.post__date {
  font-style: italic;
  white-space: nowrap;
}

.post__link {
  cursor: pointer;
  font-style: normal;
  font-weight: normal;
  text-decoration: underline;
}

.post__link:hover {
  text-decoration: none;
}

.post__body {
  border-top: none;
  padding: 0.5em;
}

.message {
  border: 1px solid #383e37;
  color: #fff;
  margin: 0.5em 0;
  padding: 0.25em 1.5em;
  text-align: center;
  width: 100%;
}

.message--error {
  background-color: #942626;
}

.message--success {
  background-color: #289426;
}

.error__heading {
  margin: 2em 0 1em;
}

.error__message {
  font-size: 18px;
}

@media (max-width: 500px) {
  .form__button {
    width: 100%;
  }
}