/* ===== Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    line-height: 1.6;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: #111;
    background: #fff;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* ===== Layout ===== */
.site-header,
.site-footer,
.site-main {
    width: 100%;
    max-width: 720px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.site-main {
    flex: 1;
    padding-top: 2rem;
    padding-bottom: 3rem;
}

/* ===== Header & Nav ===== */
.site-header {
    padding-top: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid #111;
    margin-bottom: 0;
}

.site-header h1 {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.site-header h1 a {
    color: #111;
    text-decoration: none;
}

.site-nav {
    margin-top: 0.5rem;
}

.site-nav a {
    color: #111;
    text-decoration: none;
    margin-right: 1.5rem;
    font-size: 0.9rem;
    font-weight: 500;
}

.site-nav a:hover {
    text-decoration: underline;
}

/* ===== Footer ===== */
.site-footer {
    padding-top: 1.5rem;
    padding-bottom: 1.5rem;
    border-top: 1px solid #ddd;
    font-size: 0.8rem;
    color: #666;
}

.site-footer a {
    color: #666;
}

/* ===== Typography ===== */
h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

p {
    margin-bottom: 1rem;
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    color: #fff;
    background: #111;
    border: 2px solid #111;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.15s, color 0.15s;
}

.btn:hover {
    background: #fff;
    color: #111;
}

.btn-secondary {
    background: #fff;
    color: #111;
}

.btn-secondary:hover {
    background: #111;
    color: #fff;
}

/* ===== Forms ===== */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.35rem;
    font-size: 0.9rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.6rem 0.75rem;
    font-size: 1rem;
    border: 1px solid #333;
    background: #fff;
    color: #111;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: 2px solid #111;
    outline-offset: 1px;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.form-message {
    padding: 1rem;
    margin-bottom: 1.5rem;
    border: 1px solid #111;
    background: #f8f8f8;
}

.form-message.success {
    border-color: #2a7d2a;
    color: #2a7d2a;
}

.form-message.error {
    border-color: #c00;
    color: #c00;
}

/* ===== Product Card (Landing Page) ===== */
.product {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

@media (min-width: 540px) {
    .product {
        flex-direction: row;
        align-items: flex-start;
    }
}

.product-image {
    flex-shrink: 0;
}

.product-image img {
    width: 200px;
    height: auto;
    border: 1px solid #ddd;
}

.product-info {
    flex: 1;
}

.product-price {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 1rem 0;
}

/* ===== Utility ===== */
.text-center {
    text-align: center;
}

.mt-2 {
    margin-top: 2rem;
}

.validation-message {
    color: #c00;
    font-size: 0.85rem;
    margin-top: 0.25rem;
}