.crc-calculator {
    --crc-section-bg: transparent;
    --crc-border-color: #c4c4c4;
    --crc-label-color: #888888;
    --crc-input-text: #000000;
    --crc-btn-bg: transparent;
    --crc-btn-text: #000000;
    --crc-btn-hover-bg: #333333;
    --crc-btn-hover-text: #ffffff;
    --crc-input-size: 72px;
    padding: 0;
    background: var(--crc-section-bg);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    box-sizing: border-box;
}

.crc-calculator *,
.crc-calculator *::before,
.crc-calculator *::after {
    box-sizing: border-box;
}

/* Preset */
.crc-preset-row {
    display: grid;
    grid-template-columns: 35% 35% 15%;
    gap: 24px;
    justify-content: center;
    margin-bottom: 28px;
}

.crc-preset-select {
    grid-column: 1 / -1;
    width: 100%;
    padding: 10px 14px;
    font-size: 15px;
    border: 1.5px solid var(--crc-border-color);
    border-radius: 6px;
    background: #fff;
    color: #333;
    cursor: pointer;
    outline: none;
}

.crc-preset-select:focus {
    border-color: #666;
}

/* Columns */
.crc-cols {
    display: flex;
    gap: 24px;
    justify-content: center;
    align-items: flex-start;
    flex-wrap: nowrap;
}

.crc-col {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.crc-col-distancia {
    flex: 0 0 35%;
}

.crc-col-tiempo {
    flex: 0 0 35%;
}

.crc-col-ritmo {
    flex: 0 0 15%;
}

.crc-col-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--crc-label-color);
    letter-spacing: 1.5px;
    text-transform: uppercase;
    margin-bottom: 14px;
    text-align: center;
    white-space: nowrap;
}

/* Input group */
.crc-input-group {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: nowrap;
    width: 100%;
}

.crc-input-wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.crc-input {
    width: var(--crc-input-size);
    height: var(--crc-input-size);
    padding: 0;
    border: 2px solid var(--crc-border-color);
    border-radius: 8px;
    background: #fff;
    color: var(--crc-input-text);
    font-size: 28px;
    font-weight: 700;
    text-align: center;
    outline: none;
    -moz-appearance: textfield;
    appearance: textfield;
    transition: border-color 0.2s;
}

.crc-input::-webkit-outer-spin-button,
.crc-input::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.crc-input:focus {
    border-color: #666;
}

.crc-input-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--crc-label-color);
    text-transform: lowercase;
    letter-spacing: 0.3px;
}

/* Result */
.crc-result-box {
    width: var(--crc-input-size);
    height: var(--crc-input-size);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--crc-border-color);
    border-radius: 8px;
    background: #fff;
    color: var(--crc-input-text);
    font-size: 28px;
    font-weight: 700;
    font-variant-numeric: tabular-nums;
}

.crc-result-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--crc-label-color);
    margin-top: 6px;
    letter-spacing: 0.3px;
}

/* Buttons */
.crc-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-top: 32px;
    flex-wrap: wrap;
}

.crc-btn {
    padding: 12px 32px;
    font-size: 15px;
    font-weight: 600;
    border: 2px solid var(--crc-border-color);
    border-radius: 8px;
    background: var(--crc-btn-bg);
    color: var(--crc-btn-text);
    cursor: pointer;
    transition: background 0.25s, color 0.25s, border-color 0.25s;
    letter-spacing: 0.5px;
}

.crc-btn:hover:not(:disabled) {
    background: var(--crc-btn-hover-bg);
    color: var(--crc-btn-hover-text);
    border-color: var(--crc-btn-hover-bg);
}

.crc-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    pointer-events: none;
}

.crc-btn:active:not(:disabled) {
    transform: scale(0.97);
}

@media (max-width: 700px) {
    .crc-calculator {
        --crc-input-size: 56px;
        padding: 16px;
    }

    .crc-cols {
        flex-wrap: wrap;
        gap: 16px;
    }

    .crc-col-distancia,
    .crc-col-tiempo,
    .crc-col-ritmo {
        flex: 0 0 100%;
    }

    .crc-col-ritmo {
        max-width: 180px;
    }

    .crc-input {
        font-size: 20px;
    }

    .crc-result-box {
        font-size: 20px;
    }

    .crc-btn {
        padding: 10px 20px;
        font-size: 13px;
    }
}