diff --git a/src/components/CourseVisibility.jsx b/src/components/CourseVisibility.jsx
new file mode 100644
index 0000000..a64ec18
--- /dev/null
+++ b/src/components/CourseVisibility.jsx
@@ -0,0 +1,12 @@
+import { Icon } from './Icon.jsx'
+
+export const ToolOverlay = ({ visibility, toggleVisibility }) => (
+    <div class="overlay">
+        <button class="icon primary" onClick={toggleVisibility}>
+            <Icon name={visibility ? 'visibility' : 'visibility_off'} />
+        </button>
+        <button class="icon">
+            <Icon name="close" />
+        </button>
+    </div>
+)
diff --git a/src/components/EventsView.jsx b/src/components/EventsView.jsx
index 34b1bf5..f836eb4 100644
--- a/src/components/EventsView.jsx
+++ b/src/components/EventsView.jsx
@@ -124,8 +124,15 @@ const WorkWeekView = ({ events }) => {
     )
 }
 
-const WorkWeekVerticalView = ({ events }) => {
-    const eventsByWeekday = _.groupBy(events, event => event.start.getDay())
+const WorkWeekVerticalView = ({ events, selection, setSelection, hideOtherCourses }) => {
+    const selectionSet = new Set(selection)
+
+    console.log(hideOtherCourses)
+
+    const eventsByWeekday = _.groupBy(
+        !hideOtherCourses ? events : events.filter(e => selectionSet.has(e.name)),
+        event => event.start.getDay()
+    )
 
     const dayIntervalLayout = _.mapValues(eventsByWeekday, events =>
         layoutIntervals(
@@ -216,7 +223,8 @@ const WorkWeekVerticalView = ({ events }) => {
                                             'event' +
                                             (currentlyHovered === event.data.name
                                                 ? ' highlight'
-                                                : '')
+                                                : '') +
+                                            (selectionSet.has(event.data.name) ? ' selected' : '')
                                         }
                                         data-event-id={event.data.name}
                                         style={{
@@ -228,6 +236,16 @@ const WorkWeekVerticalView = ({ events }) => {
                                                     360) +
                                                 'deg',
                                         }}
+                                        onClick={() => {
+                                            if (!selectionSet.has(event.data.name))
+                                                setSelection([...selection, event.data.name])
+                                            else
+                                                setSelection(
+                                                    selection.filter(
+                                                        name => event.data.name !== name
+                                                    )
+                                                )
+                                        }}
                                     >
                                         <div class="title">
                                             {_.startCase(_.lowerCase(event.data.name))
@@ -255,13 +273,48 @@ const WorkWeekVerticalView = ({ events }) => {
     )
 }
 
-const CourseView = ({ events }) => {
+const CourseView = ({ events, selection, setSelection }) => {
     const eventsByCourse = _.groupBy(events, 'name')
+    const selectionSet = new Set(selection)
+
+    const [currentlyHovered, setCurrentlyHovered] = useState(null)
+    const element = useRef()
+
+    useEffect(() => {
+        if (element.current) {
+            const l = e => {
+                const $course = e.target.closest('.course')
+                if ($course) {
+                    setCurrentlyHovered($course.dataset.courseId)
+                } else {
+                    setCurrentlyHovered(null)
+                }
+            }
+
+            element.current.addEventListener('mousemove', l)
+
+            return () => {
+                element.current.removeEventListener('mousemove', l)
+            }
+        }
+    }, [element.current])
+
     return (
-        <div class="course-view">
+        <div class="course-view" ref={element}>
             <div class="wrap-container">
                 {Object.entries(eventsByCourse).map(([name, courseEvents]) => (
-                    <div class="course">
+                    <div
+                        class={
+                            'course' +
+                            (currentlyHovered === name ? ' highlight' : '') +
+                            (selectionSet.has(name) ? ' selected' : '')
+                        }
+                        data-course-id={name}
+                        onClick={() => {
+                            if (!selectionSet.has(name)) setSelection([...selection, name])
+                            else setSelection(selection.filter(name => name !== name))
+                        }}
+                    >
                         <div class="title">
                             {_.startCase(_.lowerCase(name))
                                 .replaceAll('Ii', 'II')
@@ -271,7 +324,7 @@ const CourseView = ({ events }) => {
                         <div class="docenti">{courseEvents[0].docenti.join(', ')}</div>
                         <div class="events">
                             {courseEvents.map(course => (
-                                <div class="event">
+                                <div>
                                     {_.capitalize(format(course.start, 'EEEE', { locale: it }))}{' '}
                                     {format(course.start, 'H:mm')} &ndash;
                                     {format(course.end, 'H:mm')} {course.aula}
@@ -298,9 +351,11 @@ const viewModeMap = {
 export const EventsView = ({ mode, ...viewProps }) => {
     const Mode = viewModeMap[mode]
 
+    const [selectedCourses, setSelectedCourses] = useState([])
+
     return (
         <div class="events-view">
-            <Mode {...viewProps} />
+            <Mode selection={selectedCourses} setSelection={setSelectedCourses} {...viewProps} />
         </div>
     )
 }
diff --git a/src/components/Toolbar.jsx b/src/components/Toolbar.jsx
index 36d1320..8108f93 100644
--- a/src/components/Toolbar.jsx
+++ b/src/components/Toolbar.jsx
@@ -27,11 +27,6 @@ export const Toolbar = ({ mode, setMode }) => {
                         </button>
                     </div>
                 </div>
-                <div class="item option">
-                    <button class="icon">
-                        <Icon name="filter_list" />
-                    </button>
-                </div>
                 <div class="item option">
                     <button class="icon">
                         <Icon name="print" />
diff --git a/src/main.jsx b/src/main.jsx
index caf9840..4db7ddc 100644
--- a/src/main.jsx
+++ b/src/main.jsx
@@ -1,6 +1,7 @@
 import _ from 'lodash'
 import { render } from 'preact'
 import { useEffect, useState } from 'preact/hooks'
+import { ToolOverlay } from './components/CourseVisibility.jsx'
 
 import { EventsView } from './components/EventsView.jsx'
 import { Toolbar } from './components/Toolbar.jsx'
@@ -38,13 +39,18 @@ const App = ({}) => {
             })
     }, [])
 
-    const [mode, setMode] = useState('work-week-v')
+    const [mode, setMode] = useState('course')
+
+    const [hideOtherCourses, setHideOtherCourses] = useState(false)
+
+    console.log(hideOtherCourses)
 
     return (
         <>
             <Toolbar {...{ mode, setMode }} />
             <EventsView
                 mode={mode}
+                hideOtherCourses={hideOtherCourses}
                 start={new Date(2022, 10, 3)}
                 events={eventi.map(({ nome, dataInizio, dataFine, docenti, aule }) => ({
                     name: _.split(nome, '-', 1)[0].trim(),
@@ -59,6 +65,10 @@ const App = ({}) => {
                     ),
                 }))}
             />
+            <ToolOverlay
+                visibility={hideOtherCourses}
+                toggleVisibility={() => setHideOtherCourses(s => !s)}
+            />
         </>
     )
 }
diff --git a/src/styles/main.scss b/src/styles/main.scss
index a9d4c80..06b9148 100644
--- a/src/styles/main.scss
+++ b/src/styles/main.scss
@@ -20,15 +20,21 @@ html {
     --gray-350: #e8e8e8;
     --gray-500: #d8d8d8;
     --gray-600: #c0c0c0;
+    --gray-700: #b0b0b0;
+    --gray-800: #909090;
     --gray-900: #282828;
 
     // --accent-100: #e6ceff;
     // --accent-400: #d0b8ef;
     // --accent-500: #aa82db;
 
-    --accent-100: hsl(221, 100%, 88%);
-    --accent-400: hsl(221, 75%, 78%);
-    --accent-500: hsl(221, 70%, 75%);
+    // --accent-100: hsl(221, 100%, 88%);
+    // --accent-400: hsl(221, 75%, 78%);
+    // --accent-500: hsl(221, 70%, 75%);
+
+    --accent-100: #d6ffc2;
+    --accent-400: #6cc16c;
+    --accent-500: #5aa05a;
 }
 
 $device-s-width: 480px;
@@ -62,12 +68,25 @@ button,
 
     position: relative;
 
+    overflow: hidden;
+
     &:hover::after {
         content: '';
         position: absolute;
 
         inset: 0;
-        background: #00000008;
+        background: #0000000c;
+
+        z-index: 1;
+    }
+
+    &.primary {
+        background: var(--accent-100);
+        border-color: var(--accent-400);
+
+        &:hover::after {
+            background: #00000020;
+        }
     }
 
     &.icon {
@@ -85,7 +104,8 @@ button,
         border-radius: 0;
         border-right: none;
 
-        padding: inherit 0.5rem;
+        padding-left: 0.75rem;
+        padding-right: 0.75rem;
 
         &:first-child {
             padding-left: 1rem;
@@ -110,6 +130,10 @@ button,
                 & + .radio {
                     border-left-color: var(--accent-400);
                 }
+
+                &:hover::after {
+                    background: #00000018;
+                }
             }
         }
     }
@@ -150,6 +174,10 @@ body {
         align-items: center;
 
         gap: 0.5rem;
+
+        @media screen and (max-width: $device-s-width) {
+            display: none;
+        }
     }
 }
 
@@ -185,6 +213,26 @@ body {
 
                 flex-grow: 1;
 
+                position: relative;
+
+                &.selected {
+                    background: var(--gray-100);
+
+                    &::after {
+                        content: '';
+                        position: absolute;
+                        inset: -1px;
+                        border-radius: 1rem;
+
+                        border: 3px solid var(--gray-800);
+                    }
+                }
+
+                &.highlight {
+                    background: var(--gray-300);
+                    border-color: var(--gray-700);
+                }
+
                 .title {
                     font-size: 24px;
                 }
@@ -474,6 +522,8 @@ body {
                 gap: 1rem 0.5rem;
 
                 .event {
+                    position: relative;
+
                     grid-row: var(--start) / span var(--size);
                     grid-column: var(--stack) / span 1;
 
@@ -491,9 +541,22 @@ body {
 
                     padding: 0.5rem 1rem 0.5rem 0.5rem;
 
-                    &.highlight {
+                    &.selected {
                         background: var(--gray-100);
-                        border-color: var(--gray-500);
+
+                        &::after {
+                            content: '';
+                            position: absolute;
+                            inset: -1px;
+                            border-radius: 0.5rem;
+
+                            border: 3px solid var(--gray-800);
+                        }
+                    }
+
+                    &.highlight {
+                        background: var(--gray-300);
+                        border-color: var(--gray-700);
                     }
 
                     .title {
@@ -527,6 +590,28 @@ body {
     }
 }
 
+.overlay {
+    display: flex;
+    position: fixed;
+
+    bottom: 3rem;
+    right: 3rem;
+
+    gap: 0.5rem;
+
+    button {
+        padding: 0.8rem;
+
+        border-radius: 100%;
+
+        .material-symbols-outlined {
+            font-size: 22px;
+        }
+
+        box-shadow: 0 0.25rem 0.75rem #00000033;
+    }
+}
+
 // Utilities
 
 span.bold {