/* Advanced Date & Time Calculator Styles */
:root {
    --adtc-primary: #3b82f6; /* Blue */
    --adtc-primary-hover: #2563eb;
    --adtc-bg: #eff6ff;
    --adtc-card: #ffffff;
    --adtc-text: #1e40af;
    --adtc-text-muted: #1e40af;
    --adtc-border: #bfdbfe;
    --adtc-radius: 12px;
}

.adtc-wrapper {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    max-width: 700px;
    margin: 2rem auto;
    background: var(--adtc-card);
    padding: 2rem;
    border-radius: var(--adtc-radius);
    box-shadow: 0 4px 6px -1px rgba(59, 130, 246, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    border: 1px solid var(--adtc-border);
    box-sizing: border-box;
}

.adtc-wrapper * {
    box-sizing: border-box;
}

.adtc-header {
    text-align: center;
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.adtc-icon {
    color: var(--adtc-primary);
    margin-bottom: 0.5rem;
}

.adtc-header h2 {
    margin: 0 0 0.5rem 0;
    font-size: 1.5rem;
    color: var(--adtc-text);
}

.adtc-header p {
    margin: 0;
    color: var(--adtc-text-muted);
    font-size: 0.95rem;
}

.adtc-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

.adtc-input-section {
    background: var(--adtc-bg);
    padding: 1.5rem;
    border-radius: 10px;
    border: 1px solid var(--adtc-border);
}

.adtc-form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 1rem;
}

.adtc-form-row .full-width {
    grid-column: 1 / -1;
}

.adtc-form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.adtc-form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--adtc-text);
}

.adtc-form-group input,
.adtc-form-group select {
    padding: 0.75rem;
    border: 1px solid var(--adtc-border);
    border-radius: 6px;
    font-size: 0.95rem;
    background: var(--adtc-card);
    color: var(--adtc-text);
}

.adtc-form-group input:focus,
.adtc-form-group select:focus {
    outline: 2px solid var(--adtc-primary);
    border-color: transparent;
}

.adtc-options {
    background: var(--adtc-card);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--adtc-border);
    margin-bottom: 1rem;
}

.adtc-options.hidden {
    display: none;
}

.adtc-checkbox {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    color: var(--adtc-text);
    font-weight: 500;
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.adtc-checkbox input {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: var(--adtc-primary);
}

.adtc-weekday-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 0.75rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--adtc-border);
}

.adtc-weekday-options.hidden {
    display: none;
}

.adtc-btn-primary {
    width: 100%;
    padding: 0.85rem;
    background: var(--adtc-primary);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

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

.adtc-results {
    background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
    padding: 1.5rem;
    border: 2px solid var(--adtc-border);
    border-radius: 12px;
    animation: slideDown 0.4s ease-out;
}

.adtc-results.hidden {
    display: none;
}

.adtc-results h3 {
    margin: 0 0 1rem 0;
    color: var(--adtc-text);
    font-size: 1.2rem;
}

.adtc-results-content {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.adtc-result-item {
    background: var(--adtc-card);
    padding: 1rem;
    border-radius: 8px;
    border-left: 4px solid var(--adtc-primary);
}

.adtc-result-label {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--adtc-primary);
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.adtc-result-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--adtc-text);
}

.adtc-result-detail {
    font-size: 0.9rem;
    color: var(--adtc-text-muted);
    margin-top: 0.5rem;
    font-style: italic;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-15px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 640px) {
    .adtc-wrapper {
        margin: 1rem;
        padding: 1.5rem;
    }

    .adtc-form-row {
        grid-template-columns: 1fr;
    }

    .adtc-weekday-options {
        grid-template-columns: 1fr;
    }

    .adtc-result-value {
        font-size: 1.25rem;
    }
}