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

body {
    font-family: Arial, sans-serif;
    background-color: #2a2a2a;
    color: white;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.app-container {
    width: 100%;
    max-width: 400px;
    height: 100vh;
    background-color: #2a2a2a;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    position: relative;
}

/* Logo */
.logo-container {
    margin-top: 40px;
    margin-bottom: 60px;
}

.logo {
    width: 200px;
    height: auto;
}

/* Participants */
.participants-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 40px;
    flex-grow: 1;
}

.participant {
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: transform 0.3s ease;
}

.participant.speaking {
    transform: scale(1.1);
}

.participant-photo {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid transparent;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.participant.speaking .participant-photo {
    border-color: #4CAF50;
    box-shadow: 0 0 20px rgba(76, 175, 80, 0.5);
}

.participant-name {
    margin-top: 10px;
    font-size: 18px;
    font-weight: bold;
}

/* Call buttons */
.call-buttons {
    display: flex;
    gap: 30px;
    margin-bottom: 40px;
}

.call-button {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: transform 0.2s ease;
}

.call-button:hover {
    transform: scale(1.1);
}

.call-button:active {
    transform: scale(0.95);
}

.call-button img {
    width: 50px;
    height: 50px;
}

.call-on {
    background-color: #4CAF50;
}

.call-off {
    background-color: #f44336;
}

.call-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}