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

:root {
    --primary: #1a5276;
    --primary-light: #2980b9;
    --primary-dark: #0e2f44;
    --accent: #e67e22;
    --success: #27ae60;
    --danger: #c0392b;
    --bg: #f4f6f9;
    --card-bg: #ffffff;
    --text: #2c3e50;
    --text-light: #7f8c8d;
    --border: #dce1e8;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --radius: 8px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    font-size: 15px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
.app-header {
    text-align: center;
    padding: 30px 20px;
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    color: white;
    border-radius: var(--radius);
    margin-bottom: 24px;
}

.app-header h1 {
    font-size: 1.8em;
    font-weight: 700;
    margin-bottom: 6px;
}

.app-header .subtitle {
    font-size: 0.95em;
    opacity: 0.9;
}

/* Sections */
.form-section {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.section-title {
    font-size: 1.15em;
    font-weight: 600;
    color: var(--primary);
    border-bottom: 2px solid var(--primary);
    padding-bottom: 8px;
    margin-bottom: 18px;
}

.section-note {
    font-size: 0.88em;
    color: var(--text-light);
    margin-bottom: 14px;
}

.subsection {
    border-top: 1px solid var(--border);
    padding-top: 16px;
    margin-top: 16px;
}

.subsection:first-child {
    border-top: none;
    padding-top: 0;
    margin-top: 0;
}

.subsection h3 {
    font-size: 0.98em;
    font-weight: 600;
    color: var(--primary-light);
    margin-bottom: 12px;
}

/* Form Grid */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 16px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    font-size: 0.88em;
    font-weight: 500;
    color: var(--text);
    margin-bottom: 4px;
}

.form-group small {
    font-size: 0.78em;
    color: var(--text-light);
    margin-top: 2px;
}

.required {
    color: var(--danger);
}

input[type="text"],
input[type="number"],
select {
    padding: 9px 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.95em;
    transition: border-color 0.2s;
    background: #fff;
    width: 100%;
}

input[type="text"]:focus,
input[type="number"]:focus,
select:focus {
    outline: none;
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(41,128,185,0.12);
}

input[readonly] {
    background: #f0f0f0;
    color: var(--text-light);
}

/* Checkbox */
.checkbox-group {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.checkbox-group label {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.88em;
    cursor: pointer;
}

input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
}

/* Regime Selector */
.regime-selector {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.regime-option {
    cursor: pointer;
}

.regime-option input[type="radio"] {
    display: none;
}

.regime-card {
    padding: 18px;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    transition: all 0.2s;
}

.regime-card strong {
    display: block;
    font-size: 1em;
    margin-bottom: 6px;
    color: var(--primary);
}

.regime-card p {
    font-size: 0.82em;
    color: var(--text-light);
    line-height: 1.5;
}

.regime-option input[type="radio"]:checked + .regime-card {
    border-color: var(--primary);
    background: rgba(26,82,118,0.04);
    box-shadow: 0 0 0 3px rgba(26,82,118,0.1);
}

/* Computed Value Display */
.computed-value {
    margin-top: 10px;
    padding: 8px 14px;
    background: #eaf2f8;
    border-radius: 6px;
    font-size: 0.9em;
    font-weight: 500;
    color: var(--primary);
}

/* Info Box */
.info-box {
    background: #fef9e7;
    border: 1px solid #f9e79f;
    border-radius: 6px;
    padding: 14px 18px;
    margin-bottom: 14px;
    font-size: 0.88em;
}

.info-box ul {
    margin: 0;
    padding-left: 18px;
}

.info-box li {
    margin-bottom: 4px;
}

/* Buttons */
.actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 24px;
}

.btn {
    padding: 12px 28px;
    border: none;
    border-radius: 6px;
    font-size: 0.95em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary {
    background: var(--primary);
    color: white;
}

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

.btn-secondary {
    background: var(--accent);
    color: white;
}

.btn-secondary:hover {
    background: #d35400;
}

.btn-outline {
    background: transparent;
    color: var(--text-light);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    background: var(--bg);
}

/* Results Tables */
.result-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
    font-size: 0.9em;
}

.result-table caption {
    text-align: left;
    font-weight: 600;
    font-size: 1.05em;
    color: var(--primary);
    padding: 8px 0;
}

.result-table th,
.result-table td {
    padding: 8px 12px;
    border: 1px solid var(--border);
    text-align: left;
}

.result-table th {
    background: var(--primary);
    color: white;
    font-weight: 500;
}

.result-table tr:nth-child(even) {
    background: #f8f9fa;
}

.result-table .amount {
    text-align: right;
    font-family: 'Courier New', monospace;
    white-space: nowrap;
}

.result-table .total-row {
    font-weight: 700;
    background: #eaf2f8 !important;
}

.result-table .highlight-row {
    background: #d5f5e3 !important;
    font-weight: 600;
}

.result-table .negative {
    color: var(--danger);
}

.result-table .positive {
    color: var(--success);
}

/* Employee Details in Results */
.result-table td:first-child strong {
    color: var(--primary);
}

/* Declaration Section */
.declaration-section {
    margin-top: 24px;
    padding: 24px;
    border: 2px solid var(--primary);
    border-radius: var(--radius);
    background: #fdfefe;
}

.declaration-title {
    font-size: 1.05em;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 12px;
    padding-bottom: 6px;
    border-bottom: 1px solid var(--border);
    text-align: center;
    letter-spacing: 1px;
}

.declaration-text {
    font-size: 0.9em;
    line-height: 1.7;
    color: var(--text);
    text-align: justify;
}

.signature-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 30px;
}

.signature-block {
    text-align: center;
    font-size: 0.85em;
    color: var(--text);
}

.signature-block p {
    margin-top: 4px;
}

.signature-line {
    width: 80%;
    margin: 0 auto 8px auto;
    border-bottom: 1px solid #333;
    height: 40px;
}

.signature-name {
    font-weight: 600;
    color: var(--primary);
}

/* Comparison */
.comparison-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.comparison-card {
    padding: 20px;
    border-radius: var(--radius);
    border: 2px solid var(--border);
}

.comparison-card.better {
    border-color: var(--success);
    background: rgba(39,174,96,0.04);
}

.comparison-card h3 {
    font-size: 1em;
    margin-bottom: 12px;
    color: var(--primary);
}

.comparison-card .tax-amount {
    font-size: 1.6em;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 4px;
}

.comparison-card .monthly {
    font-size: 0.85em;
    color: var(--text-light);
}

.savings-banner {
    text-align: center;
    padding: 16px;
    border-radius: var(--radius);
    background: #d5f5e3;
    font-weight: 600;
    font-size: 1.05em;
    color: #1e8449;
    margin-bottom: 12px;
}

/* Footer */
.app-footer {
    text-align: center;
    padding: 20px;
    font-size: 0.82em;
    color: var(--text-light);
    border-top: 1px solid var(--border);
    margin-top: 10px;
}

/* Print Styles */
@media print {
    body {
        background: white;
        font-size: 12px;
    }
    .container {
        max-width: 100%;
        padding: 0;
    }
    .app-header {
        background: none;
        color: var(--text);
        border: 2px solid var(--text);
        border-radius: 0;
    }
    .form-section {
        box-shadow: none;
        border: 1px solid #ccc;
        break-inside: avoid;
    }
    .actions, .app-footer, #oldRegimeSection, #newRegimeSection,
    .regime-selector, .section-note, .info-box,
    .form-section:not(.results-section):not(#comparisonSection) {
        display: none !important;
    }
    .results-section, #comparisonSection {
        display: block !important;
    }
    .btn { display: none; }
    .declaration-section {
        border: 2px solid #333;
        break-inside: avoid;
    }
    .signature-line {
        border-bottom-color: #000;
    }
}

/* Responsive */
@media (max-width: 640px) {
    .form-grid {
        grid-template-columns: 1fr;
    }
    .regime-selector {
        grid-template-columns: 1fr;
    }
    .comparison-grid {
        grid-template-columns: 1fr;
    }
    .app-header h1 {
        font-size: 1.3em;
    }
    .container {
        padding: 12px;
    }
    .signature-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
}