---
marp: true
theme: gaia
paginate: true
backgroundColor: #fff
header: "Web Engineering – DHBW Stuttgart"
footer: "Michael Czechowski – SoSe 2026"
---

<style>
:root {
  --color-foreground: #1a1a2e;
  --color-highlight: #005f8a;
  --color-dimmed: #4a6a7a;
}
section.invert {
  --color-foreground: #fff;
}
section {
  font-size: 1.7rem;
}
h1 {
  color: #005f8a;
}
section.invert h1 {
  color: #fff;
}
pre {
  background: #0f1e2e;
  color: #00b4d8;
  border-radius: 8px;
  border-left: 3px solid #005f8a;
}
pre code {
  background: transparent;
  color: inherit;
}
code {
  background: #1a3a4a;
  color: #00b4d8;
  padding: 0.15em 0.4em;
  border-radius: 4px;
}
a {
  color: var(--color-highlight);
}
</style>

<!-- _class: invert -->
<!-- _header: '' -->
<!-- _backgroundColor: #001520 -->

# CSS: Extended

---

# CSS Selectors – Tag, Class, ID, Attribute

```css
/* Tag */
p { color: #333; }

/* Class */
.button { background: blue; }

/* ID */
#header { height: 60px; }

/* Attribute */
input[type="text"] { border: 1px solid #ccc; }
input[disabled] { background: #eee; }
```

---

# CSS Selectors – Attribut-Selektoren

```css
/* presence */
[disabled] { opacity: 0.5; }

/* exact value */
[type="email"] { border-color: blue; }

/* contains word */
[class~="btn"] { cursor: pointer; }

/* starts with */
[href^="https"] { color: green; }

/* ends with */
[src$=".png"] { border: 1px solid #ccc; }

/* contains substring */
[class*="icon"] { padding-left: 20px; }
```

---

# CSS Combinators

```css
/* Child (direkt) */
div > p { margin: 0; }

/* Descendant (Nachkomme) */
div p { margin: 0; }

/* Next Sibling */
h1 + p { font-size: 1.2em; }

/* Subsequent Sibling */
h1 ~ p { color: #666; }

/* Selector List */
h1, h2, h3 { font-weight: bold; }
```

---

# Pseudo Classes

```css
/* User Interaction */
:hover { color: red; }
:active { background: blue; }
:focus { outline: 2px solid orange; }

/* Structure */
:first-child { margin-left: 0; }
:last-child { margin-right: 0; }
:nth-child(odd) { background: #f9f9f9; }

/* Links */
:visited { color: purple; }
:link { color: blue; }
```

---

# Pseudo Classes – More

```css
/* Form States */
:valid { border-color: green; }
:invalid { border-color: red; }
:placeholder-shown { color: #999; }

/* Content */
:before { content: "→ "; }
:after { content: " [Wichtig]"; }
:first-letter { font-size: 2em; }
:first-line { font-weight: bold; }

/* NOT */
:not(.disabled) { pointer-events: auto; }
:not(:last-child) { border-bottom: 1px solid #ccc; }
```

---

# Shorthand Properties

```css
/* margin: top right bottom left */
margin: 10px 20px 10px 20px;

/* centering */
margin: 0 auto;

/* padding same */
padding: 20px;

/* border: width style color */
border: 1px solid #333;

/* background: color image position/size repeat */
background: #fff url(logo.png) 0 0 no-repeat;

/* font: style variant weight size/line-height family */
font: italic normal bold 16px/1.5 Arial, sans-serif;
```

---

# Flexbox Shorthands

```css
/* flex: grow shrink basis */
flex: 1 0 auto;

/* place-items: align-items justify-items */
place-items: center stretch;

/* place-content: align-content justify-content */
place-content: space-between center;

/* gap: row-gap column-gap */
gap: 20px 40px;
```

---

# CSS Custom Properties (Variables)

```css
:root {
  --primary-color: #005f8a;
  --spacing: 20px;
  --radius: 8px;
}

.button {
  background: var(--primary-color);
  padding: var(--spacing);
  border-radius: var(--radius);
}
```

---

# CSS Functions

```css
/* calc */
width: calc(100% - 40px);

/* min/max/clamp */
width: min(100%, 600px);
font-size: clamp(14px, 2vw, 20px);

/* var with fallback */
color: var(--text-color, #333);

/* rgb/rgba/hsl/hsla */
color: hsl(200, 100%, 50%);
background: rgba(0, 0, 0, 0.5);
```

---

# Transition & Animation

```css
/* transition: property duration timing-function */
transition: all 0.3s ease-in-out;
transition: background 0.2s, transform 0.1s;

/* animation */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.fade-in {
  animation: fadeIn 0.5s ease-out;
}
```

---

# CSS Specificity

Welcher Selektor gewinnt? **Punktezählung:**

```
ID            – 0,1,0,0
Class / Attr / Pseudo-Class  – 0,0,1,0
Tag / Pseudo-Element  – 0,0,0,1
Inline Style          – 1,0,0,0
!important            – setzt alles außer Kraft
```

```css
#main .btn:hover     /* 0,1,2,0 */
.btn.primary         /* 0,0,2,0 */
button[type="submit"] /* 0,0,1,1 */
```

→ Faustregel: möglichst flach. `!important` vermeiden.

---

# CSS Frameworks

| Framework | Stil |
|-----------|------|
| **Bootstrap** | Komponenten + Grid, opinionated |
| **Tailwind CSS** | Utility-First, atomar |
| **Bulma** | klassisch, ohne JS |
| **shadcn/ui** | kopierbare Komponenten (Tailwind-basiert) |
| **Flowbite** | Tailwind-Komponentenbib. |

---

# Tailwind CSS – Beispiel

```html
<button class="bg-blue-600 hover:bg-blue-700
               text-white font-semibold
               px-4 py-2 rounded-lg
               transition shadow-sm">
  Klick mich
</button>
```

- Keine eigenen CSS-Klassen mehr
- JIT-Compiler erzeugt nur genutzte Klassen
- Design-System via `tailwind.config.js`

---

<!-- _class: invert -->
<!-- _backgroundColor: #001520 -->

# No JavaScript, No Cry

## Native HTML statt JS-Komponenten

---

# Native HTML – Was früher JS brauchte

| Komponente | Native Alternative |
|------------|--------------------|
| Accordion / Collapsible | `<details>` + `<summary>` |
| Modal / Dialog | `<dialog>` |
| Date Picker | `<input type="date">` |
| Time Picker | `<input type="time">` |
| Color Picker | `<input type="color">` |
| Range Slider | `<input type="range">` |
| Progress Bar | `<progress>` |
| Auto-Complete | `<datalist>` |

→ Baseline Widely Available (Chrome, Firefox, Safari, Edge).

---

# `<details>` + `<summary>`

```html
<details>
  <summary>Mehr Infos</summary>
  <p>Hier steht der ausklappbare Inhalt.</p>
</details>
```

- Keine Zeile JS
- Tastatur-zugänglich
- Animierbar mit `::details-content` (CSS only)

---

# `<dialog>` – Native Modal

```html
<dialog id="myDialog">
  <form method="dialog">
    <p>Wirklich löschen?</p>
    <button value="cancel">Abbrechen</button>
    <button value="ok">OK</button>
  </form>
</dialog>

<button onclick="myDialog.showModal()">Öffnen</button>
```

- `showModal()` blockt Hintergrund + ESC schließt
- Backdrop via `dialog::backdrop`
- Form mit `method="dialog"` schließt + liefert `returnValue`

---

# `<input type="date">` & Co.

```html
<input type="date" min="2026-01-01" max="2026-12-31">
<input type="time" step="60">
<input type="color" value="#005f8a">
<input type="range" min="0" max="100" step="5" value="50">
<input type="number" min="1" max="300">
```

- Plattform-native UI (Touch-Datepicker auf Mobile)
- Validierung "for free"
- Locale-Awareness vom Browser

---

# `<progress>` – Native Progress Bar

```html
<progress value="70" max="100">70%</progress>

<!-- indeterminate -->
<progress></progress>
```

```css
progress {
  width: 100%;
  height: 0.5rem;
}
progress::-webkit-progress-bar { background: #eee; }
progress::-webkit-progress-value { background: #005f8a; }
```

---

# Form Validation – Native

```html
<form>
  <input type="email" required
         pattern=".+@dhbw\.de"
         title="Bitte DHBW-Mail eingeben">
  <input type="password" minlength="8" required>
  <button>Login</button>
</form>
```

- `required`, `min`, `max`, `pattern`, `step`
- `:invalid` / `:valid` CSS-Pseudoklassen
- `form.checkValidity()` / `input.setCustomValidity()`

---

# Wann doch JS?

- Komplexe Interaktion über mehrere Komponenten
- State, der nicht ins DOM gehört
- Async / Server-Sync
- Animationen mit komplexer Logik
- Cross-Browser-Polyfills (selten heute)

→ **Default: HTML/CSS. JS nur wenn nötig.**

---

# Fragen?

1. Was bedeutet `div > p` vs `div p`?
2. Wann nutzt du `nth-child(even)`?
3. Warum `--variable` statt direkt `#fff`?