:root {
    --primary-color: #007bff;
    --primary-hover: #0056b3;
    --bg-color: #f0f2f5;
    --card-bg: #ffffff;
    --text-color: #333333;
    --text-secondary: #666666;
    --border-color: #e4e6eb;
    --success-color: #28a745;
    --radius-lg: 16px;
    --radius-sm: 8px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
}

* {
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    /* Center horizontally */
    align-items: flex-start;
    /* Align to top */
}

/* Container behaves like a mobile screen on small devices */
.container {
    width: 100%;
    max-width: 600px;
    background: var(--card-bg);
    margin: 0 auto;
    min-height: 100vh;
    box-shadow: none;
    padding-bottom: 160px;
    /* Space for fixed footer */
    position: relative;
}

/* Desktop enhancements: Card look */
@media (min-width: 601px) {
    body {
        padding: 40px 20px;
        align-items: center;
        /* Center vertically on desktop */
    }

    .container {
        min-height: auto;
        border-radius: var(--radius-lg);
        box-shadow: var(--shadow-md);
        padding: 40px;
        margin: auto;
        /* Center in body */
    }
}

.logo {
    text-align: center;
    padding: 20px 0;
}

.logo img {
    height: 60px;
    width: auto;
}

h2 {
    text-align: center;
    margin: 0 0 24px 0;
    font-size: 1.5rem;
    font-weight: 700;
}

.section {
    background: #fff;
    margin-bottom: 24px;
    border-radius: var(--radius-sm);
}

/* On mobile, sections could be just spacing, but let's keep it clean */
@media (max-width: 600px) {
    .section {
        padding: 0 20px;
    }
}

.section-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-color);
    display: flex;
    align-items: center;
}

.form-group {
    margin-bottom: 16px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

input[type="text"],
input[type="email"],
input[type="date"],
input[type="number"],
input[type="tel"] {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 16px;
    /* Prevents zoom on iOS */
    transition: border-color 0.2s, box-shadow 0.2s;
    background: #f9f9f9;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.1);
}

/* Add-ons Styling */
.addon-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.addon-item {
    display: flex;
    align-items: center;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: #fff;
    cursor: pointer;
    transition: all 0.2s;
}

.addon-item:hover {
    border-color: var(--primary-color);
}

.addon-item input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin-right: 12px;
    accent-color: var(--primary-color);
}

.addon-info {
    flex: 1;
}

.addon-title {
    font-weight: 600;
    display: block;
    color: var(--text-color);
}

.addon-price {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Footer & Price Calculation */
.sticky-footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #fff;
    padding: 16px 20px;
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.1);
    z-index: 100;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

/* Constrain footer on desktop */
@media (min-width: 601px) {
    .sticky-footer {
        position: static;
        box-shadow: none;
        padding: 20px 0 0 0;
        border-top: 1px solid var(--border-color);
        margin-top: 20px;
    }
}

.price-summary {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-color);
    margin-bottom: 5px;
}

.price-detail {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-align: right;
    font-weight: normal;
}

.btn-primary {
    display: block;
    width: 100%;
    padding: 14px;
    background-color: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    text-align: center;
    transition: background-color 0.2s;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.agb {
    margin: 20px 0;
    display: flex;
    align-items: flex-start;
    padding: 0 20px;
}

@media (min-width: 601px) {
    .agb {
        padding: 0;
    }
}

.agb input {
    margin-top: 4px;
    margin-right: 10px;
    width: 18px;
    height: 18px;
}

.agb label {
    font-size: 0.9rem;
    line-height: 1.4;
    margin: 0;
}

.agb a {
    color: var(--primary-color);
    text-decoration: none;
}

/* Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    visibility: hidden;
    opacity: 0;
    transition: opacity 0.3s, visibility 0.3s;
    z-index: 1000;
}

.overlay.active {
    visibility: visible;
    opacity: 1;
}

.overlay-content {
    background: #fff;
    padding: 24px;
    border-radius: var(--radius-lg);
    max-width: 600px;
    width: 90%;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: var(--shadow-md);
}

.close {
    background: var(--bg-color);
    color: var(--text-color);
    padding: 12px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 1rem;
    margin-top: 20px;
    font-weight: 600;
}

.close:hover {
    background: #e4e6eb;
}