html, body { 
    height: 100%; 
    margin: 0; 
    padding: 0; 
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; 
    background-color: #000000; 
    overflow: hidden;
}

#app-container { 
    min-height: 100vh; 
    display: flex; 
    flex-direction: column; 
    background-color: #000000; 
}

/* --- HEADER --- */
.header-app { 
    background-color: #000000; 
    color: white; 
    padding: 1rem 1.5rem; 
    display: flex; 
    align-items: center; 
    justify-content: space-between;
    border-bottom: 1px solid #333;
    height: 60px;
}

.header-logo-text { 
    font-weight: bold; 
    font-size: 1.25rem; 
    color: white; 
    text-transform: uppercase; 
    letter-spacing: 1px;
}

/* --- LOGIN SCREEN --- */
.login-screen {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    padding: 2rem;
    box-sizing: border-box;
    background: radial-gradient(circle at center, #1a1a1a 0%, #000000 100%);
}

.login-box { width: 100%; max-width: 350px; }

.input-group { margin-bottom: 1.5rem; }
.input-group label { display: block; color: #fff; margin-bottom: 0.5rem; font-size: 0.9rem; }
.form-input { 
    width: 100%; padding: 12px; font-size: 1rem; border-radius: 8px; border: 1px solid #333; 
    background: #222; color: white; outline: none; box-sizing: border-box;
}
.form-input:focus { border-color: #ef4444; }

/* --- MAIN SCREEN (SCANNER) --- */
.main-screen {
    display: flex;
    flex-direction: column;
    height: 100vh;
    background-color: #111;
}

.scan-container {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

/* BOTÓN GIGANTE NFC */
.nfc-button {
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: linear-gradient(145deg, #1e1e1e, #2a2a2a);
    box-shadow:  20px 20px 60px #0c0c0c, -20px -20px 60px #262626;
    border: 4px solid #333;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 30px;
    position: relative;
}

.nfc-button i { color: #ef4444; font-size: 4rem; margin-bottom: 10px; transition: color 0.3s; }
.nfc-button span { color: #fff; font-weight: bold; font-size: 1.2rem; text-transform: uppercase; }

.nfc-button:active { transform: scale(0.95); box-shadow: inset 5px 5px 10px #0c0c0c, inset -5px -5px 10px #262626; }

/* ESTADO ESCANEANDO */
.nfc-button.scanning {
    border-color: #ef4444;
    animation: pulse 1.5s infinite;
}
.nfc-button.scanning i { color: #fff; }

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.4); }
    70% { box-shadow: 0 0 0 30px rgba(239, 68, 68, 0); }
    100% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0); }
}

.info-text { color: #888; text-align: center; margin-top: 20px; font-size: 0.9rem; }

/* --- BOTONES --- */
.btn-primary { 
    width: 100%; padding: 15px; border-radius: 8px; border: none; 
    background: #ef4444; color: white; font-weight: bold; font-size: 1rem; cursor: pointer; text-transform: uppercase;
}
.btn-primary:hover { background: #dc2626; }

/* --- MODALES --- */
.modal-overlay {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.85); z-index: 1000;
    display: none; justify-content: center; align-items: center;
    flex-direction: column; text-align: center;
}
.modal-content { background: white; padding: 30px; border-radius: 15px; width: 80%; max-width: 300px; }
.modal-icon { font-size: 3rem; margin-bottom: 15px; }