diff --git a/mamweb/settings_common.py b/mamweb/settings_common.py
index 75a5493c..925d5961 100644
--- a/mamweb/settings_common.py
+++ b/mamweb/settings_common.py
@@ -78,6 +78,7 @@ TEMPLATES = [
                 'django.contrib.messages.context_processors.messages',
                 'sekizai.context_processors.sekizai',
                 'header_fotky.context_processors.vzhled',
+                'various.context_processors.april',
             )
         },
     },
@@ -132,6 +133,7 @@ INSTALLED_APPS = (
     'korektury',
     'prednasky',
     'header_fotky',
+    'various',
 
     # Admin upravy:
 
diff --git a/mamweb/templates/base.html b/mamweb/templates/base.html
index b79060b5..8f2b7a7d 100644
--- a/mamweb/templates/base.html
+++ b/mamweb/templates/base.html
@@ -131,6 +131,48 @@
 	   $("a[rel^='gallery-image']").prettyPhoto(prettyparams);
 	});
     </script>
+	{% if april == 2021 %}
+    <script type="text/javascript" charset="utf-8">
+	function rotace(vektor, uhel_deg) {
+		var uhel = uhel_deg *(Math.PI / 180);
+		var x = vektor[0];
+		var y = vektor[1];
+		return [x*Math.cos(uhel) - y*Math.sin(uhel), x*Math.sin(uhel) + y*Math.cos(uhel)];
+	}
+
+	function rotace_a_posun(obj, uhel) {
+		var ow = obj.width();
+		var oh = obj.height();
+
+		var rohy = [[0,0], [0,oh], [ow, 0], [ow, oh]];
+		var minx = 0;
+		var miny = 0;
+		for (var roh of rohy) {
+			var otoceny = rotace(roh, uhel);
+			if (otoceny[0] < minx) {
+				minx = otoceny[0];
+			}
+			if (otoceny[1] < miny) {
+				miny = otoceny[1];
+			}
+		}
+
+		miny *= -1;
+		minx *= -1;
+
+		var transf_str = "translateX("+minx+"px) translateY("+miny+"px) rotate("+uhel+"deg)";
+		obj.css('transform-origin', 'top left');
+		obj.css('transform', transf_str);
+	}
+
+	function randomUhel() {
+		return Math.floor(360*Math.random());
+	}
+
+	$('.container').css('margin', 0);
+	rotace_a_posun($('.container'), randomUhel());
+	</script>
+	{% endif %}
     {% render_block "js" %}
   </body>
 </html>
diff --git a/seminar/templates/seminar/odevzdavatko/detail.html b/seminar/templates/seminar/odevzdavatko/detail.html
index dadeff41..14094fb8 100644
--- a/seminar/templates/seminar/odevzdavatko/detail.html
+++ b/seminar/templates/seminar/odevzdavatko/detail.html
@@ -1,5 +1,6 @@
 {% extends "base.html" %}
 {% load static %}
+{% load deadliny %}
 
 {% block content %}
 
@@ -62,7 +63,9 @@ $(document).ready(function(){
 <p>Řešitelé: {{ object.resitele.all | join:", " }}</p>
 
 {# https://docs.djangoproject.com/en/3.1/ref/models/instances/#django.db.models.Model.get_FOO_display #}
-<p>Forma: {{ object.get_forma_display }}, doručeno {{ object.cas_doruceni }}</p>
+<p>Forma: {{ object.get_forma_display }}</p>
+
+<p>Doručeno {{ object.cas_doruceni }}, deadline: {{object.cas_doruceni | deadline_html }}</p>
 
 {# Soubory: #}
 <h3>Přílohy:</h3>
diff --git a/seminar/templates/seminar/registrace/password_reset_email.html b/seminar/templates/seminar/registrace/password_reset_email.html
index 8e7186f9..8687a6cb 100644
--- a/seminar/templates/seminar/registrace/password_reset_email.html
+++ b/seminar/templates/seminar/registrace/password_reset_email.html
@@ -4,5 +4,5 @@ Obdrželi jsme od Tebe žádost o obnovu hesla uživatele {{ user }} na webu M&M
 Pro zadání nového hesla přejdi na následující stránku:
 {{ protocol}}://{{ domain }}{% url 'password_reset_confirm' uidb64=uid token=token %}
 
-S pozdravem,
+S pozdravem
 organizátoři M&M
\ No newline at end of file
diff --git a/seminar/templatetags/deadliny.py b/seminar/templatetags/deadliny.py
new file mode 100644
index 00000000..b7a0142d
--- /dev/null
+++ b/seminar/templatetags/deadliny.py
@@ -0,0 +1,25 @@
+from django import template
+from django.utils.safestring import mark_safe
+from seminar.utils import TypDeadline, deadline
+register = template.Library()
+
+@register.filter(name='deadline')
+def deadline_text(datum):
+	typ, cislo, dl = deadline(datum)
+	strings = {
+		TypDeadline.PredDeadline: f"1. deadline čísla {cislo} ({dl})",
+		TypDeadline.SousDeadline: f"Soustřeďkový deadline čísla {cislo} ({dl})",
+		TypDeadline.FinalDeadline: f"Finální deadline čísla {cislo} ({dl})",
+		}
+	return strings[typ]
+
+@register.filter(name='deadline_html')
+def deadline_html(datum):
+	typ, _, _ = deadline(datum)
+	text = deadline_text(datum)
+	classes = {
+		TypDeadline.PredDeadline: 'preddeadline',
+		TypDeadline.SousDeadline: 'sous_deadline',
+		TypDeadline.FinalDeadline: 'final_deadline',
+		}
+	return mark_safe(f'<span class="{classes[typ]}">{text}</span>')
diff --git a/seminar/utils.py b/seminar/utils.py
index a41b4111..68bce110 100644
--- a/seminar/utils.py
+++ b/seminar/utils.py
@@ -309,7 +309,7 @@ def deadline_v_rocniku(datum, rocnik):
 			deadliny.append((TypDeadline.FinalDeadline, c, c.datum_deadline))
 	deadliny = sorted(deadliny, key=lambda x: x[2])	# podle data
 	for dl in deadliny:
-		if datum <= dl:
+		if datum <= dl[2]:
 			# První takový deadline je ten nejtěsnější
 			return dl
 
@@ -319,20 +319,22 @@ def deadline(datum):
 	Vrací trojici (TypDeadline, Cislo, datumDeadline: date).
 	"""
 
+	if isinstance(datum, datetime.datetime):
+		datum = datum.date()
 	rok = datum.year
 	# Dva ročníky podezřelé z obsahování dat
-	pozdejsi_rocnik = m.Rocnik.filter(prvni_rok=rok)
-	drivejsi_rocnik = m.Rocnik.filter(druhy_rok=rok)
-	if any(
+	pozdejsi_rocnik = m.Rocnik.objects.filter(prvni_rok=rok)
+	drivejsi_rocnik = m.Rocnik.objects.filter(prvni_rok=rok-1)
+	if any([
 			pozdejsi_rocnik.count() > 1,
 			drivejsi_rocnik.count() > 1,
-			):
+			]):
 		raise ValueError(f"Více ročníků začíná/končí stejným rokem: {rok}")
 	pozdejsi_rocnik = pozdejsi_rocnik.first() if pozdejsi_rocnik.count() > 0 else None
 	drivejsi_rocnik = drivejsi_rocnik.first() if drivejsi_rocnik.count() > 0 else None
 
 	# Předpokládáme, že neexistuje číslo, které má deadline ale nemá finální deadline.
-	posledni_deadline_drivejsiho_rocniku = m.Cislo.objects.get(rocnik=drivejsi_rocnik, datum_deadline__isnull=False).datum_deadline
+	posledni_deadline_drivejsiho_rocniku = m.Cislo.objects.filter(rocnik=drivejsi_rocnik, datum_deadline__isnull=False).last().datum_deadline
 
 	if datum <= posledni_deadline_drivejsiho_rocniku:
 		return deadline_v_rocniku(datum, drivejsi_rocnik)
diff --git a/various/__init__.py b/various/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/various/admin.py b/various/admin.py
new file mode 100644
index 00000000..8c38f3f3
--- /dev/null
+++ b/various/admin.py
@@ -0,0 +1,3 @@
+from django.contrib import admin
+
+# Register your models here.
diff --git a/various/apps.py b/various/apps.py
new file mode 100644
index 00000000..c24a4428
--- /dev/null
+++ b/various/apps.py
@@ -0,0 +1,5 @@
+from django.apps import AppConfig
+
+
+class VariousConfig(AppConfig):
+    name = 'various'
diff --git a/various/context_processors.py b/various/context_processors.py
new file mode 100644
index 00000000..c0be2975
--- /dev/null
+++ b/various/context_processors.py
@@ -0,0 +1,14 @@
+def april(req):
+	if 'X-April' in req.headers:
+		try:
+			year = int(req.headers['X-April'])
+			return {'april': year}
+		except:
+			pass # Fall-back to regular behaviour
+	
+	import datetime
+	today = datetime.date.today()
+	if today.day == 1 and today.month == 4:
+		return {'april': today.year}
+	return {}
+
diff --git a/various/migrations/__init__.py b/various/migrations/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/various/models.py b/various/models.py
new file mode 100644
index 00000000..71a83623
--- /dev/null
+++ b/various/models.py
@@ -0,0 +1,3 @@
+from django.db import models
+
+# Create your models here.
diff --git a/various/tests.py b/various/tests.py
new file mode 100644
index 00000000..7ce503c2
--- /dev/null
+++ b/various/tests.py
@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.
diff --git a/various/views.py b/various/views.py
new file mode 100644
index 00000000..91ea44a2
--- /dev/null
+++ b/various/views.py
@@ -0,0 +1,3 @@
+from django.shortcuts import render
+
+# Create your views here.