body {
    min-height: 100vh;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;

    font-family: Arial, sans-serif;
    background-color: #0b1622;
    color: #e8f1f2;
    transition: background 0.4s ease, color 0.4s ease;
}

header {
    background-color: #0e1d2c;
    border-bottom: 2px solid #15d1f9;
    padding: 10px 20px;
    color: #fff;
    box-shadow: 0 3px 10px rgba(0, 255, 255, 0.1);
    transition: all 0.4s ease;
}

.header-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo img {
    width: 75px;
    cursor: pointer;
}

.header-top h1 {
    flex-grow: 1;
    text-align: center;
    color: #15d1f9;
    font-size: 2em;
    text-shadow: 0 0 6px rgba(21, 209, 249, 0.7);
}

.theme-toggle button {
    background: none;
    color: #15d1f9;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    text-shadow: 0 0 5px rgba(21, 209, 249, 0.5);
}

.header-bottom ul {
    list-style: none;
    display: flex;
    gap: 150px;
    padding: 10px 20px;
    border-radius: 8px;
    background-color: #142636;
    box-shadow: 0 0 10px rgba(21, 209, 249, 0.15);
}

.header-bottom ul li a {
    text-decoration: none;
    font-weight: bold;
    color: #e8f1f2;
    transition: 0.2s;
}

.header-bottom ul li a:hover {
    color: #15d1f9;
}

.section-chat {
    background-color: #132232;
    border-radius: 12px;
    box-shadow: 0 0 20px rgba(21, 209, 249, 0.1);
    padding: 25px;
    width: 60%;
    max-width: 900px;
    margin: 20px auto;
    flex: 1;
    display: flex;
    flex-direction: column;
    transition: all 0.4s ease;
}

body.dark-mode .section-chat {
    background-color: #1a2b3a;
}

.section-chat h2 {
    font-size: 1.6em;
    color: #15d1f9;
    margin-bottom: 10px;
    text-shadow: 0 0 5px rgba(21, 209, 249, 0.4);
}

#chatbox {
    background-color: #0e1d2c;
    color: #e8f1f2;
    border-radius: 12px;
    height: 350px;
    padding: 15px;
    overflow-y: auto;
    box-shadow: inset 0 0 10px rgba(21, 209, 249, 0.08);
}

#ia {
    background-color: #1a2b3a;
    border-left: 3px solid #15d1f9;
    border-radius: 10px;
    padding: 10px;
    max-width: 60%;
    margin: 10px 0;
}

#user {
    align-self: flex-end;
    background: linear-gradient(90deg, #0ea0c6, #15d1f9);
    border-radius: 10px;
    padding: 10px;
    max-width: 60%;
    color: white;
    margin: 10px 0;
}

#spinner {
    display: none;
}

#search-bar {
    width: 80%;
    padding: 10px;
    border-radius: 8px;
    border: 2px solid #15d1f9;
    background-color: #0e1d2c;
    color: #e8f1f2;
}

#search-button {
    background-color: #15d1f9;
    border: none;
    padding: 10px 20px;
    color: #0b1622;
    font-weight: bold;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.2s;
}

#search-button:hover {
    background-color: #0ea0c6;
}

#select {
    background-color: #0b1622;
    color: #e8f1f2;
}

#accueil {
    width: 10%;
    display: flex;
    margin: 20px auto;
    padding: 12px 30px;
    background: #3b82f6;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1em;
    cursor: pointer;
    font-weight: bold;
    text-transform: uppercase;
    transition: 0.3s ease, box-shadow 0.3s ease, transform 0.3s ease;
}

#accueil:hover {
    background: #3b82f6;
    color: #0d1b2a;
    transform: translateY(-5px) scale(1.05);
}