:root {
    --blue: #2196f3;
    --dark-blue: #1565c0;
    --bg: #f5f7fa;
}

body {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    background-color: var(--bg);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
}

.app-card {
    background: white;
    width: 90%;
    max-width: 450px;
    padding: 25px;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.1);
}

header {
    text-align: center;
    border-bottom: 2px solid #eee;
    margin-bottom: 20px;
}

header h1 { color: var(--blue); margin: 0; }

.input-box {
    margin-bottom: 15px;
}

label {
    display: block;
    font-size: 0.9rem;
    margin-bottom: 5px;
    font-weight: bold;
}

input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 8px;
    box-sizing: border-box;
}

button {
    width: 100%;
    padding: 15px;
    background: var(--blue);
    color: white;
    border: none;
    border-radius: 8px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s;
}

button:hover { background: var(--dark-blue); }

.hidden { display: none; }

.status-panel {
    background: #e3f2fd;
    padding: 20px;
    border-radius: 12px;
    margin-top: 20px;
    text-align: center;
}

.highlight {
    font-size: 2.5rem;
    font-weight: 900;
    color: var(--dark-blue);
    margin: 10px 0;
}

footer {
    text-align: center;
    margin-top: 20px;
    color: #999;
}