diff --git a/static/style.css b/static/style.css
deleted file mode 100644
index fe3f619..0000000
--- a/static/style.css
+++ /dev/null
@@ -1,238 +0,0 @@
-:root {
-    --primary: #2563eb;
-    --primary-dark: #1e40af;
-    --background: #f8fafc;
-    --surface: #fff;
-    --border: #e5e7eb;
-    --text: #1e293b;
-    --shadow: 0 2px 8px rgba(30,41,59,0.07);
-}
-body {
-    background: var(--background);
-    color: var(--text);
-    font-family: 'Segoe UI', Arial, sans-serif;
-    margin: 0;
-    padding: 0;
-}
-.container {
-    max-width: 480px;
-    margin: 3em auto;
-    background: var(--surface);
-    border-radius: 16px;
-    box-shadow: var(--shadow);
-    padding: 2.5em 2em 2em 2em;
-    border: 1px solid var(--border);
-}
-h1 {
-    text-align: center;
-    margin-bottom: 2em;
-    font-size: 2.1em;
-    letter-spacing: 0.01em;
-}
-form {
-    margin-bottom: 2.2em;
-    padding-bottom: 1.2em;
-    border-bottom: 1px solid var(--border);
-}
-form:last-of-type {
-    border-bottom: none;
-    margin-bottom: 0;
-}
-h2 {
-    font-size: 1.15em;
-    margin-bottom: 0.7em;
-    color: var(--primary-dark);
-}
-label {
-    display: block;
-    margin-bottom: 0.7em;
-    font-weight: 500;
-}
-.date-row {
-    display: flex;
-    align-items: center;
-    gap: 0.5em;
-    margin-top: 0.2em;
-}
-.date-calc-row {
-    display: flex;
-    align-items: center;
-    gap: 0.5em;
-    margin-top: 0.2em;
-}
-input[type="date"] {
-    padding: 0.45em 0.7em;
-    border: 1px solid var(--border);
-    border-radius: 6px;
-    font-size: 1em;
-    background: #f1f5f9;
-    color: var(--text);
-}
-.today-btn {
-    padding: 0.35em 0.9em;
-    background: var(--primary-dark);
-    color: #fff;
-    border: none;
-    border-radius: 6px;
-    font-size: 0.95em;
-    font-weight: 500;
-    cursor: pointer;
-    transition: background 0.2s;
-}
-.today-btn:hover {
-    background: var(--primary);
-}
-button, .accordion-header {
-    background: var(--primary);
-    color: #fff;
-    border: none;
-    border-radius: 6px;
-    font-size: 1em;
-    font-weight: 600;
-    cursor: pointer;
-    box-shadow: 0 1px 3px rgba(30,41,59,0.05);
-    transition: background 0.2s;
-}
-
-/* Berechnungs-Buttons vergrößern */
-button[type="submit"] {
-    font-size: 1.1em;
-    padding: 0.8em 1.5em;
-    min-width: 140px;
-    margin-top: 1.2em;
-}
-
-button:hover, .accordion-header:hover {
-    background: var(--primary-dark);
-}
-button:focus, .accordion-header:focus {
-    outline: 3px solid #facc15;
-    outline-offset: 2px;
-    box-shadow: 0 0 0 4px #1e293b;
-    z-index: 2;
-}
-.result {
-    margin-top: 1em;
-    font-weight: bold;
-    background: #e0e7ff;
-    color: #1e293b;
-    border-radius: 6px;
-    padding: 0.7em 1em;
-    box-shadow: 0 1px 2px rgba(30,41,59,0.04);
-    border: 2px solid #2563eb;
-}
-.accordion {
-    border-radius: 12px;
-    overflow: hidden;
-    box-shadow: var(--shadow);
-    background: var(--surface);
-    margin-bottom: 2em;
-}
-.accordion-item + .accordion-item {
-    border-top: 1px solid var(--border);
-}
-.accordion-header {
-    background: var(--primary-dark);
-    color: #fff;
-    cursor: pointer;
-    padding: 1em 1.2em;
-    font-size: 1.1em;
-    font-weight: 600;
-    border: none;
-    outline: none;
-    width: 100%;
-    text-align: left;
-    transition: background 0.2s;
-}
-.accordion-header.active, .accordion-header:hover {
-    background: var(--primary);
-}
-.accordion-content {
-    display: none;
-    padding: 1.2em 1.2em 1em 1.2em;
-    background: var(--surface);
-}
-.accordion-content.active {
-    display: block;
-}
-.header-tage {
-    background: #2563eb;
-    color: #fff;
-}
-.header-tage.active, .header-tage:hover {
-    background: #1e40af;
-    color: #fff;
-}
-.header-werktage {
-    background: #059669;
-    color: #fff;
-}
-.header-werktage.active, .header-werktage:hover {
-    background: #047857;
-    color: #fff;
-}
-.header-wochentag {
-    background: #f59e42;
-    color: #1e293b;
-}
-.header-wochentag.active, .header-wochentag:hover {
-    background: #d97706;
-    color: #fff;
-}
-.header-plusminus-tage {
-    background: #a21caf;
-    color: #fff;
-}
-.header-plusminus-tage.active, .header-plusminus-tage:hover {
-    background: #701a75;
-    color: #fff;
-}
-.header-plusminus-werktage {
-    background: #0ea5e9;
-    color: #fff;
-}
-.header-plusminus-werktage.active, .header-plusminus-werktage:hover {
-    background: #0369a1;
-    color: #fff;
-}
-.header-plusminus-wochenmonate {
-    background: #f43f5e;
-    color: #fff;
-}
-.header-plusminus-wochenmonate.active, .header-plusminus-wochenmonate:hover {
-    background: #be123c;
-    color: #fff;
-}
-.header-kw {
-    background: #a78bfa;
-    color: #1e293b;
-}
-.header-kw.active, .header-kw:hover {
-    background: #7c3aed;
-    color: #fff;
-}
-.header-kw-datum {
-    background: #facc15;
-    color: #1e293b;
-}
-.header-kw-datum.active, .header-kw-datum:hover {
-    background: #ca8a04;
-    color: #fff;
-}
-.header-plusminus {
-    background: #be123c;
-    color: #fff;
-}
-.header-plusminus.active, .header-plusminus:hover {
-    background: #7f1d1d;
-    color: #fff;
-}
-@media (max-width: 600px) {
-    .container {
-        margin: 1em;
-        padding: 1.2em 0.7em 1em 0.7em;
-    }
-    h1 {
-        font-size: 1.3em;
-    }
-} 
\ No newline at end of file
diff --git a/templates/index.html b/templates/index.html
index b3385be..8345293 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -26,7 +26,297 @@
     <meta name="application-name" content="Elpatrons Datumsrechner">
     <meta name="msapplication-TileColor" content="#2563eb">
     <link rel="icon" type="image/x-icon" href="/static/favicon.ico">
-    <link rel="stylesheet" href="/static/style.css">
+    <style>
+:root {
+    --primary: #2563eb;
+    --primary-dark: #1e40af;
+    --background: #f8fafc;
+    --surface: #fff;
+    --border: #e5e7eb;
+    --text: #1e293b;
+    --shadow: 0 2px 8px rgba(30,41,59,0.07);
+}
+body {
+    background: var(--background);
+    color: var(--text);
+    font-family: 'Segoe UI', Arial, sans-serif;
+    margin: 0;
+    padding: 0;
+}
+.container {
+    max-width: 480px;
+    margin: 3em auto;
+    background: var(--surface);
+    border-radius: 16px;
+    box-shadow: var(--shadow);
+    padding: 2.5em 2em 2em 2em;
+    border: 1px solid var(--border);
+}
+h1 {
+    text-align: center;
+    margin-bottom: 2em;
+    font-size: 2.1em;
+    letter-spacing: 0.01em;
+}
+form {
+    margin-bottom: 2.2em;
+    padding-bottom: 1.2em;
+    border-bottom: 1px solid var(--border);
+}
+form:last-of-type {
+    border-bottom: none;
+    margin-bottom: 0;
+}
+h2 {
+    font-size: 1.15em;
+    margin-bottom: 0.7em;
+    color: var(--primary-dark);
+}
+label {
+    display: block;
+    margin-bottom: 0.7em;
+    font-weight: 500;
+}
+.date-row {
+    display: flex;
+    align-items: center;
+    gap: 0.5em;
+    margin-top: 0.2em;
+}
+.date-calc-row {
+    display: flex;
+    align-items: center;
+    gap: 0.5em;
+    margin-top: 0.2em;
+}
+input[type="date"] {
+    padding: 0.45em 0.7em;
+    border: 1px solid var(--border);
+    border-radius: 6px;
+    font-size: 1em;
+    background: #f1f5f9;
+    color: var(--text);
+}
+.today-btn {
+    padding: 0.35em 0.9em;
+    background: var(--primary-dark);
+    color: #fff;
+    border: none;
+    border-radius: 6px;
+    font-size: 0.95em;
+    font-weight: 500;
+    cursor: pointer;
+    transition: background 0.2s;
+}
+.today-btn:hover {
+    background: var(--primary);
+}
+button, .accordion-header {
+    background: var(--primary);
+    color: #fff;
+    border: none;
+    border-radius: 6px;
+    font-size: 1em;
+    font-weight: 600;
+    cursor: pointer;
+    box-shadow: 0 1px 3px rgba(30,41,59,0.05);
+    transition: background 0.2s;
+}
+
+/* Berechnungs-Buttons vergrößern */
+button[type="submit"] {
+    font-size: 1.1em;
+    padding: 0.8em 1.5em;
+    min-width: 140px;
+    margin-top: 1.2em;
+}
+
+button:hover, .accordion-header:hover {
+    background: var(--primary-dark);
+}
+button:focus, .accordion-header:focus {
+    outline: 3px solid #facc15;
+    outline-offset: 2px;
+    box-shadow: 0 0 0 4px #1e293b;
+    z-index: 2;
+}
+.result {
+    margin-top: 1em;
+    font-weight: bold;
+    background: #e0e7ff;
+    color: #1e293b;
+    border-radius: 6px;
+    padding: 0.7em 1em;
+    box-shadow: 0 1px 2px rgba(30,41,59,0.04);
+    border: 2px solid #2563eb;
+}
+.accordion {
+    border-radius: 12px;
+    overflow: hidden;
+    box-shadow: var(--shadow);
+    background: var(--surface);
+    margin-bottom: 2em;
+    /* Layout-Shift-Prävention */
+    min-height: 200px;
+    contain: layout style paint;
+}
+.accordion-item + .accordion-item {
+    border-top: 1px solid var(--border);
+    margin-top: 0.5em;
+}
+.accordion-header {
+    background: var(--primary-dark);
+    color: #fff;
+    cursor: pointer;
+    padding: 1em 1.2em;
+    font-size: 1.1em;
+    font-weight: 600;
+    border: none;
+    outline: none;
+    width: 100%;
+    text-align: left;
+    transition: background 0.2s;
+}
+.accordion-header.active, .accordion-header:hover {
+    background: var(--primary);
+}
+.accordion-content {
+    display: none;
+    padding: 1.2em 1.2em 1em 1.2em;
+    background: var(--surface);
+    max-height: 0;
+    overflow: hidden;
+    transition: max-height 0.3s ease-out, padding 0.3s ease-out;
+    opacity: 0;
+}
+.accordion-content.active {
+    display: block;
+    max-height: 500px;
+    opacity: 1;
+    transition: max-height 0.3s ease-in, padding 0.3s ease-in, opacity 0.3s ease-in;
+}
+.header-tage {
+    background: #2563eb;
+    color: #fff;
+}
+.header-tage.active, .header-tage:hover {
+    background: #1e40af;
+    color: #fff;
+}
+.header-werktage {
+    background: #059669;
+    color: #fff;
+}
+.header-werktage.active, .header-werktage:hover {
+    background: #047857;
+    color: #fff;
+}
+.header-wochentag {
+    background: #f59e42;
+    color: #1e293b;
+}
+.header-wochentag.active, .header-wochentag:hover {
+    background: #d97706;
+    color: #fff;
+}
+.header-plusminus-tage {
+    background: #a21caf;
+    color: #fff;
+}
+.header-plusminus-tage.active, .header-plusminus-tage:hover {
+    background: #701a75;
+    color: #fff;
+}
+.header-plusminus-werktage {
+    background: #0ea5e9;
+    color: #fff;
+}
+.header-plusminus-werktage.active, .header-plusminus-werktage:hover {
+    background: #0369a1;
+    color: #fff;
+}
+.header-plusminus-wochenmonate {
+    background: #f43f5e;
+    color: #fff;
+}
+.header-plusminus-wochenmonate.active, .header-plusminus-wochenmonate:hover {
+    background: #be123c;
+    color: #fff;
+}
+.header-kw {
+    background: #a78bfa;
+    color: #1e293b;
+}
+.header-kw.active, .header-kw:hover {
+    background: #7c3aed;
+    color: #fff;
+}
+.header-kw-datum {
+    background: #facc15;
+    color: #1e293b;
+}
+.header-kw-datum.active, .header-kw-datum:hover {
+    background: #ca8a04;
+    color: #fff;
+}
+.header-plusminus {
+    background: #be123c;
+    color: #fff;
+}
+.header-plusminus.active, .header-plusminus:hover {
+    background: #7f1d1d;
+    color: #fff;
+}
+@media (max-width: 600px) {
+    .container {
+        margin: 1em;
+        padding: 1.2em 0.7em 1em 0.7em;
+    }
+    h1 {
+        font-size: 1.3em;
+    }
+}
+
+/* Touch-Target Optimierungen für Footer-Links */
+footer a {
+    display: inline-block;
+    padding: 0.5em 0.8em;
+    margin: 0.3em 0.2em;
+    min-height: 44px;
+    min-width: 44px;
+    line-height: 1.4;
+    text-decoration: none;
+    border-radius: 6px;
+    transition: background-color 0.2s, color 0.2s;
+    position: relative;
+}
+
+footer a:hover {
+    background-color: rgba(37, 99, 235, 0.1);
+    text-decoration: underline;
+}
+
+footer a:focus {
+    outline: 3px solid #facc15;
+    outline-offset: 2px;
+    background-color: rgba(37, 99, 235, 0.1);
+}
+
+/* Zusätzlicher Abstand zwischen Footer-Links */
+footer br + a {
+    margin-top: 0.5em;
+}
+
+/* Responsive Anpassungen für Footer */
+@media (max-width: 600px) {
+    footer a {
+        padding: 0.6em 1em;
+        margin: 0.4em 0.3em;
+        min-height: 48px;
+        min-width: 48px;
+    }
+}
+    </style>
     <link rel="manifest" href="/static/manifest.json">
     <meta name="theme-color" content="#2563eb">
     <script>
@@ -46,9 +336,21 @@
             });
         }
         document.addEventListener('DOMContentLoaded', function() {
-            openAccordion(parseInt("{{ active_idx|default(0) }}"));
-            // Tastatursteuerung für Accordion
+            // Sofortige Aktivierung der ersten Accordion-Sektion um Layout-Shifts zu vermeiden
+            const activeIdx = parseInt("{{ active_idx|default(0) }}");
             const headers = document.querySelectorAll('.accordion-header');
+            const panels = document.querySelectorAll('.accordion-content');
+            
+            // Sofort den aktiven Zustand setzen
+            headers.forEach((btn, i) => {
+                btn.classList.toggle('active', i === activeIdx);
+                btn.setAttribute('aria-expanded', i === activeIdx ? 'true' : 'false');
+            });
+            panels.forEach((el, i) => {
+                el.classList.toggle('active', i === activeIdx);
+            });
+            
+            // Tastatursteuerung für Accordion
             headers.forEach((header, idx) => {
                 header.addEventListener('keydown', function(e) {
                     if (e.key === 'Enter' || e.key === ' ') {
@@ -85,14 +387,14 @@
         </div>
         <div class="accordion">
             <div class="accordion-item">
-                <button type="button" class="accordion-header header-tage" id="accordion-header-0" aria-expanded="true" aria-controls="accordion-panel-0" role="button" tabindex="0" onclick="openAccordion(0)">
+                <button type="button" class="accordion-header header-tage active" id="accordion-header-0" aria-expanded="true" aria-controls="accordion-panel-0" role="button" tabindex="0" onclick="openAccordion(0)">
                     <span style="vertical-align:middle;display:inline-block;width:1.5em;">
                         <!-- Kalender mit Doppelpfeil -->
                         <svg width="24" height="24" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg"><rect x="3" y="5" width="18" height="16" rx="4" fill="#fff" stroke="#2563eb" stroke-width="2"/><rect x="3" y="5" width="18" height="4" rx="2" fill="#2563eb"/><rect x="6" y="2" width="2" height="4" rx="1" fill="#2563eb"/><rect x="16" y="2" width="2" height="4" rx="1" fill="#2563eb"/><path d="M8 15h8M8 15l2-2M8 15l2 2M16 15l-2-2M16 15l-2 2" stroke="#2563eb" stroke-width="1.5" stroke-linecap="round"/></svg>
                     </span>
                     Anzahl der Tage/Werktage zwischen zwei Daten
                 </button>
-                <div class="accordion-content" id="accordion-panel-0" role="region" aria-labelledby="accordion-header-0">
+                <div class="accordion-content active" id="accordion-panel-0" role="region" aria-labelledby="accordion-header-0">
                     <form method="post">
                         <label for="start1">Startdatum:<br>
                             <span class="date-row">