.container {
    width: min(960px, calc(100% - 32px));
    min-height: 100vh;
    margin: 0 auto;
    padding: 24px 0 28px;
    display: flex;
    flex-direction: column;
}

header {
    padding: 10px 4px 20px;
    text-align: center;
}

header h1 {
    margin: 0;
    color: var(--text);
    font-size: clamp(1.35rem, 3vw, 1.65rem);
    font-weight: 700;
    letter-spacing: -0.025em;
}

header p {
    margin: 5px 0 0;
    color: var(--muted);
    font-size: 0.84rem;
}

.chat {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: calc(100vh - 125px);
}

.messages {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 2px;
    min-height: 0;
    padding: 18px 8px 120px;
    overflow-y: auto;
    scroll-behavior: smooth;
    scrollbar-width: thin;
    scrollbar-color: var(--border-strong) transparent;
}

.messages::-webkit-scrollbar {
    width: 7px;
}

.messages::-webkit-scrollbar-track {
    background: transparent;
}

.messages::-webkit-scrollbar-thumb {
    border-radius: 999px;
    background: var(--border-strong);
}

.message {
    display: flex;
    width: 100%;
    padding: 9px 4px;
    animation: message-in 180ms ease-out;
}

.message.user {
    justify-content: flex-end;
}

.bubble {
    max-width: min(74%, 680px);
    padding: 11px 15px;
    border-radius: 16px;
    color: var(--text);
    line-height: 1.65;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
}

.message.user .bubble {
    border: 1px solid var(--border);
    border-bottom-right-radius: 5px;
    background: var(--bg-soft);
    box-shadow: var(--shadow-sm);
}

.message.assistant .bubble {
    max-width: min(88%, 780px);
    padding: 7px 0;
    border: 0;
    background: transparent;
    box-shadow: none;
}

.sources {
    margin-top: 12px;
    padding-top: 10px;
    border-top: 1px solid var(--border);
    color: var(--muted);
    font-size: 0.78rem;
    line-height: 1.55;
}

.sources strong {
    color: var(--text-soft);
    font-weight: 650;
}

/* Zone de saisie */
.composer {
    position: sticky;
    bottom: 0;
    z-index: 5;
    margin-top: -80px;
    padding: 18px 4px 8px;
    background: linear-gradient(
        to bottom,
        rgba(245, 247, 251, 0),
        rgba(245, 247, 251, 0.92) 35%,
        var(--bg) 70%
    );
}

.composer form {
    display: flex;
    align-items: flex-end;
    gap: 8px;
    width: 100%;
    padding: 8px 8px 8px 16px;
    border: 1px solid var(--border-strong);
    border-radius: 18px;
    background: var(--surface);
    box-shadow:
        0 4px 18px rgba(15, 23, 42, 0.07),
        0 1px 3px rgba(15, 23, 42, 0.04);
    transition:
        border-color var(--transition),
        box-shadow var(--transition);
}

.composer form:focus-within {
    border-color: rgba(37, 99, 235, 0.45);
    box-shadow:
        0 0 0 3px rgba(37, 99, 235, 0.08),
        0 6px 22px rgba(15, 23, 42, 0.08);
}

.composer textarea {
    flex: 1;
    min-height: 42px;
    max-height: 180px;
    margin: 0;
    padding: 9px 2px;
    border: 0;
    outline: 0;
    resize: none;
    background: transparent;
    color: var(--text);
    font-size: 0.94rem;
    line-height: 1.5;
}

.composer textarea::placeholder {
    color: #94a3b8;
}

/* Bouton Envoyer */
.composer button {
    min-width: 130px;
    min-height: 48px;
    padding: 14px 22px;
    border: 0;
    border-radius: 13px;
    background: linear-gradient(
        135deg,
        var(--primary),
        var(--primary-hover)
    );
    color: #fff;
    font-weight: 750;
    font-size: 14px;
    cursor: pointer;
    box-shadow: 0 12px 30px rgba(37, 99, 235, 0.16);
    transition:
        transform 0.2s ease,
        box-shadow 0.2s ease,
        background 0.2s ease;
}

.composer button:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 16px 34px rgba(37, 99, 235, 0.24);
}

.composer button:active:not(:disabled) {
    transform: translateY(0);
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.18);
}

.composer button:focus-visible {
    outline: none;
    box-shadow:
        0 0 0 3px var(--surface),
        0 0 0 6px rgba(37, 99, 235, 0.30);
}

.composer button:disabled {
    opacity: 0.45;
    cursor: not-allowed;
    box-shadow: none;
}

.status {
    min-height: 18px;
    margin: 6px 4px 0;
    color: var(--muted);
    font-size: 0.76rem;
}

.status.error {
    color: var(--danger);
}

@keyframes message-in {
    from {
        opacity: 0;
        transform: translateY(5px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 700px) {
    .container {
        width: min(100% - 18px, 960px);
        padding-top: 12px;
    }

    header {
        padding-bottom: 12px;
    }

    .messages {
        padding: 12px 2px 110px;
    }

    .bubble {
        max-width: 86%;
    }

    .message.assistant .bubble {
        max-width: 94%;
    }

    .composer {
        padding-left: 0;
        padding-right: 0;
    }

    .composer form {
        border-radius: 16px;
        padding-left: 13px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .message {
        animation: none;
    }

    .composer button {
        transition: none;
    }
}