body {
    /* Motif mosaïque 1 carré sur 2 avec une petite icône */
    background-color: white;
    background-image: repeating-linear-gradient(90deg, transparent, transparent 32px, rgba(0,0,0,0.03) 32px, rgba(0,0,0,0.03) 64px),
                      repeating-linear-gradient(0deg, transparent, transparent 32px, rgba(0,0,0,0.03) 32px, rgba(0,0,0,0.03) 64px),
                      url('img/faire-rapport.png');
    background-size: 64px 64px, 64px 64px, 32px 32px;
    background-position: 0 0, 0 0, 0 0;
    background-repeat: repeat;
}
:root {
    --bg-dark: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent-blue: #38bdf8;
    --accent-cyan: #06b6d4;
    --btn-disabled: #334155;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', system-ui, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.app-container {
    max-width: 600px;
    width: 100%;
    margin: 60px auto 20px auto;
    padding: 20px;
    box-sizing: border-box;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    font-size: 2.8em;
    margin: 0;
    background: linear-gradient(to right, var(--accent-blue), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -1px;
}

.subtitle-bg {
    display: inline-block;
    background: var(--card-bg);
    color: var(--text-main);
    padding: 12px 24px;
    border-radius: 12px;
    margin-top: 10px;
    font-size: 1.1em;
    box-shadow: 0 2px 8px 0 rgba(0,0,0,0.08);
}

.form-card {
    background-color: var(--card-bg);
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
    border: 1px solid #334155;
}

.input-group {
    margin-bottom: 25px;
}

.input-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-main);
    font-weight: 600;
    font-size: 0.95em;
}

select {
    width: 100%;
    padding: 14px;
    background-color: #0f172a;
    border: 2px solid #334155;
    border-radius: 10px;
    color: var(--text-main);
    font-size: 1em;
    outline: none;
    transition: border-color 0.2s;
    cursor: pointer;
}

select:focus:not(:disabled) {
    border-color: var(--accent-blue);
}

select:disabled {
    background-color: #1e293b;
    opacity: 0.5;
    cursor: not-allowed;
}

.actions-container {
    display: flex;
    gap: 15px;
    margin-top: 35px;
}

.btn {
    flex: 1;
    padding: 16px;
    border: none;
    border-radius: 10px;
    font-size: 1em;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.1s, opacity 0.2s;
}

.btn:active:not(:disabled) {
    transform: scale(0.98);
}

.btn.primary {
    background: linear-gradient(to right, var(--accent-blue), var(--accent-cyan));
    color: #0f172a;
}

.btn.secondary {
    background-color: #334155;
    color: var(--text-main);
    border: 1px solid #475569;
}

.btn:disabled {
    background: var(--btn-disabled) !important;
    color: var(--text-muted) !important;
    border: none !important;
    cursor: not-allowed;
    opacity: 0.6;
}

#notification {
    background-color: #10b981;
    color: white;
    text-align: center;
    padding: 12px;
    border-radius: 8px;
    margin-top: 20px;
    font-size: 0.9em;
    transition: opacity 0.3s;
}

.hidden {
    opacity: 0;
    pointer-events: none;
}

footer {
    text-align: center;
    padding: 20px;
    color: var(--text-muted);
    font-size: 0.85em;
}

@media (max-width: 480px) {
    .form-card { padding: 20px; }
    .actions-container { flex-direction: column; }
}