body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #e5e7eb;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}
.container {
    background: white;
    width: 100%;
    max-width: 800px;
    height: 90vh;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}
h1 {
    text-align: center;
    font-size: 1.4rem;
    color: #111827;
    padding: 20px;
    margin: 0;
    border-bottom: 1px solid #f3f4f6;
    background: #ffffff;
}
#kurulum-ekrani {
    padding: 30px;
    overflow-y: auto;
}
input, textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 20px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    box-sizing: border-box;
    transition: border-color 0.3s;
}
input:focus, textarea:focus {
    outline: none;
    border-color: #2563eb;
}
button {
    background-color: #2563eb;
    color: white;
    border: none;
    padding: 15px;
    font-size: 1.1rem;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    font-weight: bold;
    transition: background-color 0.3s;
}
button:hover { background-color: #1d4ed8; }

/* Güncellenen Alan: Mesajların taşmasını engeller */
#sohbet-ekrani {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0; 
    background: #f9fafb;
}

#mesajlar {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}
.mesaj {
    max-width: 75%;
    padding: 15px 20px;
    border-radius: 15px;
    line-height: 1.5;
    font-size: 0.95rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
.ik-uzmani {
    background-color: #ffffff;
    color: #1f2937;
    align-self: flex-start;
    border-bottom-left-radius: 4px;
    border: 1px solid #e5e7eb;
}
.aday {
    background-color: #2563eb;
    color: white;
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}
.girdi-alani {
    display: flex;
    padding: 15px;
    background: white;
    border-top: 1px solid #e5e7eb;
    gap: 10px;
}
.girdi-alani input { margin: 0; flex: 1; }
.girdi-alani button { width: 120px; padding: 0; }