:root {
    /* Tints of #1f254c — #1f254c is the darkest color in the scale */
    --navy-900: #1f254c; /* base color, darkest */
    --navy-800: #353b5e;
    --navy-700: #4c5170;
    --navy-600: #626682;
    --navy-500: #797c94;
    --navy-400: #8f92a6;
    --navy-300: #a5a8b7;
    --navy-200: #bcbec9;
    --navy-100: #d2d3db;
    --navy-50: #f4f4f6;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Roboto', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--navy-900);
    color: var(--navy-50);
    display: flex;
    justify-content: center;
    padding: 40px 20px;
}

.container {
    width: 100%;
    max-width: 480px;
    background-color: var(--navy-800);
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
    padding: 30px;
}

h1 {
    margin-top: 0;
    text-align: center;
    font-size: 32px;
    color: var(--navy-50);
    padding-bottom: 15px;
}

.field {
    display: flex;
    align-items: center;
    margin-bottom: 16px;
}

select {
    width: 100%;
    padding: 10px;
    font-size: 16px;
    border-radius: 5px;
    border: 1px solid var(--navy-600);
    background-color: var(--navy-700);
    color: var(--navy-50);
    cursor: pointer;
}

.label {
    font-weight: bold;
    flex-grow: 1;
    color: var(--navy-100);
}

.guest-label-input {
    font-weight: bold;
    flex-grow: 1;
    border: none;
    background: transparent;
    font-size: 16px;
    font-family: inherit;
    padding: 4px 0;
    color: var(--navy-100);
}

.guest-label-input:focus {
    outline: none;
    border-bottom: 1px solid var(--navy-300);
}

.period-options {
    gap: 24px;
}

.radio-option {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-weight: bold;
    color: var(--navy-100);
}

.radio-option input[type="radio"] {
    appearance: none;
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    margin: 0;
    border: 2px solid var(--navy-500);
    border-radius: 4px;
    background-color: var(--navy-700);
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
}

.radio-option input[type="radio"]:checked {
    background-color: var(--navy-300);
    border-color: var(--navy-300);
}

.radio-option input[type="radio"]:checked::after {
    content: '\2713';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -55%);
    color: var(--navy-900);
    font-size: 13px;
    line-height: 1;
}

.number-input {
    width: 100px;
    padding: 10px;
    font-size: 16px;
    border-radius: 5px;
    border: 1px solid var(--navy-600);
    background-color: var(--navy-700);
    color: var(--navy-50);
}

#add-guest-btn {
    display: block;
    width: 100%;
    background-color: var(--navy-300);
    color: var(--navy-900);
    border: none;
    padding: 12px;
    font-size: 15px;
    border-radius: 5px;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 20px;
}

#add-guest-btn:hover {
    background-color: var(--navy-200);
}

.service-charge-row {
    border-top: 2px solid var(--navy-600);
    padding-top: 16px;
    margin-bottom: 0;
}

#service-charge-value {
    font-size: 22px;
    font-weight: bold;
    color: var(--navy-100);
}