* {
            box-sizing: border-box;
        }

        body {
            font-family: Inter, Arial, sans-serif;
            background: #eef2f7;
            margin: 0;
        }

        .header {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 25px;
            justify-content: space-between;
        }

        .header-left {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .reset-all {
            background: #f3f4f6;
            border: 1px solid #e5e7eb;
            border-radius: 8px;
            padding: 8px 14px;
            font-size: 14px;
            cursor: pointer;
            transition: all 0.15s ease;
        }

        .reset-all:hover {
            background: #e5e7eb;
        }

        .logo {
            width: 36px;
            height: 36px;
            object-fit: contain;
            transform: translateY(-2px);
        }

        .container {
            max-width: 900px;
            margin: 60px auto;
            background: white;
            padding: 30px 40px;
            border-radius: 20px;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
        }

        h2 {
            margin: 0;
        }

        .row {
            margin-bottom: 15px;
        }

        label {
            display: block;
            font-size: 14px;
            color: #666;
            margin-bottom: 4px;
        }

        select,
        input {
            width: 100%;
            padding: 8px 10px;
            border-radius: 6px;
            border: 1px solid #ddd;
            font-size: 14px;
        }

        .result {
            margin-top: 25px;
            padding: 15px;
            background: #f2f5ff;
            border-radius: 8px;
            font-size: 16px;
        }

        .tariffs {
            margin-top: 20px;
            padding-top: 10px;
            border-top: 1px solid #eee;
        }

        .tariff-block {
            margin-top: 15px;
            padding: 10px;
            background: #fafafa;
            border-radius: 8px;
        }

        .tariff-row {
            margin-top: 6px;
        }

        button {
            margin-top: 8px;
            padding: 6px 10px;
            border-radius: 6px;
            border: none;
            background: #eee;
            cursor: pointer;
        }

        .step-card {
            background: #ffffff;
            border-radius: 14px;
            padding: 25px;
            margin-top: 28px;

            border: 1px solid #e3e8ef;

            box-shadow:
                0 1px 2px rgba(16, 24, 40, 0.04),
                0 4px 10px rgba(16, 24, 40, 0.06);
        }

        .result-card {
            background: #eff6ff;
            border-radius: 14px;
            padding: 25px;
            margin-top: 28px;

            border: 1px solid #bfdbfe;

            box-shadow:
                0 1px 2px rgba(16, 24, 40, 0.04),
                0 4px 10px rgba(16, 24, 40, 0.05);
        }

        .result-card b {
            color: #1d4ed8;
            font-size: 17px;
        }

        h3 {
            margin-top: 0;
            margin-bottom: 20px;
            font-size: 18px;
        }

        .grid-3 {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr;
            gap: 20px;
        }

        .grid-4 {
            grid-template-columns: 1fr 1fr 1fr;
        }

        .grid-2 {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
            margin-top: 20px;
        }

        .step-card input,
        .step-card select {
            margin-bottom: 10px;
        }

        .grid-3,
        .grid-4,
        .grid-2 {
            margin-bottom: 12px;
        }

        .input-error {
            border: 1px solid #ef4444;
            background: #fff5f5;
        }

        .input-error-text {
            color: #ef4444;
            font-size: 12px;
            margin-top: -6px;
            margin-bottom: 8px;
        }

        .hint {
            display: inline-block;
            width: 16px;
            height: 16px;
            margin-left: 6px;
            border-radius: 50%;
            background: rgba(0, 0, 0, 0.15);
            color: #fff;
            font-size: 12px;
            text-align: center;
            line-height: 16px;
            cursor: default;
            position: relative;
        }

        .hint::after {
            content: "?";
            font-weight: bold;
        }

        /* tooltip */
        .hint::before {
            content: attr(data-hint);
            position: absolute;
            bottom: 130%;
            left: 50%;
            transform: translateX(-50%);

            background: #111;
            color: #fff;

            padding: 10px 12px;
            border-radius: 8px;

            font-size: 12px;
            line-height: 1.4;

            width: max-content;
            max-width: 260px;

            white-space: normal;
            word-wrap: break-word;

            opacity: 0;
            pointer-events: none;
            transition: 0.15s;
            z-index: 10;
        }

        /* стрелочка */
        .hint::after,
        .hint::before {
            pointer-events: none;
        }

        .hint:hover::before {
            opacity: 1;
        }