:root {
    color-scheme: light dark;
    --bg: #f6f7f4;
    --surface: #ffffff;
    --surface-soft: #f1f4ef;
    --text: #18211b;
    --muted: #637068;
    --border: #d9dfda;
    --accent: #176b45;
    --accent-hover: #105637;
    --accent-soft: #e5f4eb;
    --danger: #b42318;
    --focus: #74b993;
    --shadow: 0 12px 32px rgba(31, 48, 38, 0.07);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    line-height: 1.5;
}

button, input, select { font: inherit; }
button { cursor: pointer; }

a { color: var(--accent); }

.site-header, main, .site-footer {
    width: min(100% - 32px, 720px);
    margin-inline: auto;
}

.site-header { padding: 28px 0 20px; }

.header-row, .section-heading, .card-heading, .actions, .result-line {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; }
.brand-mark { width: 38px; height: 38px; color: var(--accent); }
.language-link { font-size: 0.9rem; font-weight: 700; text-decoration: none; padding: 8px 11px; border: 1px solid var(--border); border-radius: 9px; background: var(--surface); }

h1 { margin: 28px 0 5px; font-size: clamp(1.8rem, 7vw, 2.55rem); letter-spacing: -0.035em; line-height: 1.15; }
.intro { color: var(--muted); margin: 0; }

.toolbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 8px 0 16px; }
.currency-control { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 0.9rem; }
.currency-control select { min-width: 68px; }

.product-list { display: grid; gap: 14px; }
.product-card, .results, .guide, .faq {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
}

.product-card { padding: 18px; position: relative; transition: border-color 0.2s, box-shadow 0.2s; }
.product-card.best { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent-soft), var(--shadow); }
.card-heading { min-height: 32px; margin-bottom: 14px; }
.card-heading h2 { font-size: 1.08rem; margin: 0; }
.best-badge { color: var(--accent); background: var(--accent-soft); font-size: 0.78rem; font-weight: 800; border-radius: 999px; padding: 5px 9px; }
.remove-button { color: var(--danger); background: transparent; border: 0; padding: 6px; font-size: 0.85rem; }

.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.field { min-width: 0; }
.field.name-field { grid-column: 1 / -1; }
label { display: block; margin-bottom: 5px; font-size: 0.86rem; font-weight: 700; }
input, select {
    width: 100%;
    height: 46px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--surface);
    color: var(--text);
    padding: 0 12px;
}
input:focus, select:focus, button:focus-visible, a:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
input.invalid { border-color: var(--danger); }
.field-error { min-height: 18px; color: var(--danger); font-size: 0.78rem; margin-top: 3px; }
.price-wrap { position: relative; }
.price-wrap span { position: absolute; left: 12px; top: 11px; color: var(--muted); }
.price-wrap input { padding-left: 34px; }

.card-summary { border-top: 1px solid var(--border); margin-top: 11px; padding-top: 11px; display: flex; justify-content: space-between; gap: 12px; color: var(--muted); font-size: 0.87rem; }
.card-summary strong { color: var(--text); }

.actions { margin: 16px 0 26px; }
.button { min-height: 44px; border-radius: 10px; border: 1px solid var(--border); padding: 9px 15px; font-weight: 750; background: var(--surface); color: var(--text); }
.button.primary { background: var(--accent); color: white; border-color: var(--accent); }
.button.primary:hover { background: var(--accent-hover); }
.button:disabled { opacity: 0.5; cursor: not-allowed; }

.results, .guide, .faq { padding: 20px; margin-bottom: 18px; }
.section-heading h2, .guide h2, .faq h2 { margin: 0; font-size: 1.25rem; }
.base-picker { width: auto; max-width: 130px; height: 40px; }
.empty-state, .compatibility-message { color: var(--muted); margin: 12px 0 0; }
.compatibility-message { color: var(--danger); background: color-mix(in srgb, var(--danger) 7%, transparent); padding: 12px; border-radius: 9px; }
.ranking { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 8px; }
.ranking li { background: var(--surface-soft); padding: 11px 12px; border-radius: 10px; }
.ranking li:first-child { background: var(--accent-soft); }
.rank-name { font-weight: 750; }
.result-line { align-items: baseline; }
.result-value { font-variant-numeric: tabular-nums; white-space: nowrap; }
.saving { margin: 12px 0 0; color: var(--accent); font-weight: 700; }

.guide p { color: var(--muted); margin-bottom: 0; }
.faq details { border-top: 1px solid var(--border); padding: 13px 0; }
.faq details:first-of-type { margin-top: 12px; }
.faq summary { font-weight: 750; cursor: pointer; }
.faq p { color: var(--muted); margin-bottom: 0; }
.site-footer { color: var(--muted); font-size: 0.82rem; text-align: center; padding: 10px 0 30px; }
.site-footer p { margin: 0 0 8px; }
.footer-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 16px; }
.footer-links a { color: var(--muted); text-underline-offset: 3px; }
.footer-links a:hover { color: var(--accent); }
.noscript { padding: 12px; background: #fff0e8; color: #7a2e0e; text-align: center; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

@media (max-width: 420px) {
    .site-header, main, .site-footer { width: min(100% - 24px, 720px); }
    .field-grid { grid-template-columns: 1fr; }
    .field.name-field { grid-column: auto; }
    .product-card { padding: 15px; }
    .card-summary { flex-direction: column; gap: 3px; }
    .result-line { align-items: flex-start; }
    .result-value { white-space: normal; text-align: right; }
}

@media (max-width: 560px) {
    .site-header { padding: 10px 0 6px; }
    .site-header h1 { margin-top: 8px; font-size: 1.55rem; }
    .site-header .intro { font-size: 0.9rem; }
    .brand-mark { width: 32px; height: 32px; }
    .toolbar { margin-top: 0; margin-bottom: 6px; }

    .product-list.pair-layout {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 8px;
    }

    .pair-layout .product-card { padding: 10px; border-radius: 12px; }
    .pair-layout .card-heading { align-items: flex-start; flex-wrap: wrap; gap: 4px; min-height: 27px; margin-bottom: 7px; }
    .pair-layout .card-heading h2 { font-size: 0.92rem; }
    .pair-layout .best-badge { padding: 3px 6px; font-size: 0.67rem; }
    .pair-layout .field-grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 5px; }
    .pair-layout .name-field,
    .pair-layout .price-field,
    .pair-layout .quantity-field { grid-column: 1 / -1; }
    .pair-layout label { margin-bottom: 2px; font-size: 0.72rem; }
    .pair-layout input,
    .pair-layout select { height: 36px; padding-inline: 8px; font-size: 0.88rem; }
    .pair-layout .price-wrap span { left: 8px; top: 7px; }
    .pair-layout .price-wrap input { padding-left: 25px; }
    .pair-layout .field-error:empty { min-height: 0; margin: 0; }
    .pair-layout .field-error { font-size: 0.68rem; line-height: 1.2; }
    .pair-layout .card-summary { margin-top: 7px; padding-top: 7px; flex-direction: column; gap: 1px; font-size: 0.72rem; }
    .pair-layout .card-summary strong { display: block; overflow-wrap: anywhere; }
    .actions { margin-top: 10px; }
}

@media (prefers-color-scheme: dark) {
    :root { --bg: #111713; --surface: #1a221d; --surface-soft: #222d26; --text: #eef4ef; --muted: #aab6ae; --border: #354139; --accent: #69ce96; --accent-hover: #54b880; --accent-soft: #1d3d2a; --danger: #ff8b82; --focus: #69ce96; --shadow: none; }
    .button.primary { color: #092616; }
}