/* Modern CSS Variables */
:root {
    --primary-color: #667eea;
    --primary-dark: #5a67d8;
    --secondary-color: #764ba2;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-muted: #9ca3af;
    --border-color: #e5e7eb;
    --border-focus: #3b82f6;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-muted: #f3f4f6;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
}

/* Container and Main Layout */
#uc-ultrasonic-calculator-container { max-width: 1200px; margin: 2rem auto; padding: var(--spacing-lg); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif; }
.calculator-card { background: var(--bg-primary); border-radius: var(--border-radius-lg); box-shadow: var(--shadow-xl); overflow: hidden; position: relative; border: 1px solid var(--border-color); }
.calculator-header { background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%); color: white; position: relative; overflow: hidden; }
.calculator-header::before { content: ''; position: absolute; top: 0; left: -100%; width: 100%; height: 100%; background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent); animation: shimmer 3s infinite; }
@keyframes shimmer { 0% { left: -100%; } 50% { left: 100%; } 100% { left: 100%; } }
.header-content { display: flex; justify-content: space-between; align-items: center; padding: var(--spacing-2xl) var(--spacing-xl); position: relative; z-index: 1; }
.header-title h2 { font-size: 2.5rem; font-weight: 800; margin: 0 0 0.5rem 0; text-shadow: 0 2px 4px rgba(0,0,0,0.1); }
.header-title h3 { font-size: 1.25rem; font-weight: 500; margin: 0; opacity: 0.9; }
.currency-display { text-align: right; }
.currency-badge { background: rgba(255,255,255,0.15); backdrop-filter: blur(10px); padding: var(--spacing-sm) var(--spacing-md); border-radius: var(--border-radius); border: 1px solid rgba(255,255,255,0.2); font-weight: 600; }
.currency-badge .rate { display: block; font-size: 1.1em; margin-top: 0.25rem; color: #fbbf24; }
.calculator-body { padding: var(--spacing-2xl); }
.form-section { margin-bottom: var(--spacing-2xl); }
.form-section:last-child { margin-bottom: 0; }
.section-title { font-size: 1.5rem; font-weight: 700; color: var(--text-primary); margin: 0 0 var(--spacing-lg) 0; display: flex; align-items: center; gap: var(--spacing-sm); }
.section-title::after { content: ''; flex: 1; height: 2px; background: linear-gradient(to right, var(--primary-color), transparent); }
.form-grid { display: grid; gap: var(--spacing-lg); margin-bottom: var(--spacing-lg); }
.primary-grid { grid-template-columns: 2fr 1fr; }
.dimensions-grid { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.material-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: var(--spacing-lg); }
.form-group { display: flex; flex-direction: column; }
.form-group label { font-weight: 600; color: var(--text-primary); margin-bottom: var(--spacing-sm); font-size: 0.95rem; display: flex; align-items: center; gap: var(--spacing-xs); }
.form-group input { padding: var(--spacing-md); border: 2px solid var(--border-color); border-radius: var(--border-radius); font-size: 1rem; font-weight: 500; background: var(--bg-primary); color: var(--text-primary); transition: all 0.2s ease; min-height: 44px; line-height: 1.5; }
.form-group input:focus { outline: none; border-color: var(--border-focus); box-shadow: 0 0 0 3px rgb(59 130 246 / 0.1); transform: translateY(-1px); }
.form-group input::placeholder { color: var(--text-muted); }
.select-wrapper { position: relative; border-radius: var(--border-radius); border: 2px solid var(--border-color); background: var(--bg-primary); overflow: hidden; transition: all 0.2s ease; }
.select-wrapper:focus-within { border-color: var(--border-focus); box-shadow: 0 0 0 3px rgb(59 130 246 / 0.1); transform: translateY(-1px); }
.select-wrapper::after { content: '▼'; position: absolute; right: var(--spacing-md); top: 50%; transform: translateY(-50%); pointer-events: none; color: var(--text-secondary); font-size: 0.8rem; z-index: 1; }
.select-wrapper select { appearance: none; -webkit-appearance: none; -moz-appearance: none; background-image: none; width: 100%; padding: 12px var(--spacing-xl) 12px var(--spacing-md); border: none; background-color: transparent; font-size: 1rem; font-weight: 500; color: var(--text-primary); cursor: pointer; line-height: 1.3; min-height: 44px; box-sizing: border-box; }
.select-wrapper select:focus { outline: none; }
.select-wrapper select option { background: var(--bg-primary); color: var(--text-primary); }
.select-wrapper select.select-placeholder { color: var(--text-muted); }
.options-section { background: var(--bg-secondary); padding: var(--spacing-xl); border-radius: var(--border-radius); border: 1px solid var(--border-color); }
.options-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: var(--spacing-lg); margin-bottom: var(--spacing-lg); }
.option-card { background: var(--bg-primary); border-radius: var(--border-radius); padding: var(--spacing-lg); border: 2px solid var(--border-color); transition: all 0.2s ease; }
.option-card:hover { border-color: var(--primary-color); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.modern-checkbox { display: flex; align-items: flex-start; gap: var(--spacing-md); cursor: pointer; user-select: none; }
.modern-checkbox input[type="checkbox"] { display: none; }
.checkmark { width: 24px; height: 24px; border: 2px solid var(--border-color); border-radius: 6px; display: flex; align-items: center; justify-content: center; background: var(--bg-primary); transition: all 0.2s ease; flex-shrink: 0; margin-top: 2px; }
.checkmark svg { width: 14px; height: 14px; opacity: 0; transform: scale(0.5); transition: all 0.2s ease; }
.modern-checkbox input:checked + .checkmark { background: var(--primary-color); border-color: var(--primary-color); }
.modern-checkbox input:checked + .checkmark svg { opacity: 1; transform: scale(1); color: white; }
.modern-checkbox.disabled { opacity: 0.5; cursor: not-allowed; }
.form-group.disabled select, .form-group.disabled input { cursor: not-allowed; background-color: var(--bg-muted); }
.form-group.disabled label { cursor: not-allowed; }
.option-content { flex: 1; }
.option-title { font-weight: 600; color: var(--text-primary); display: block; margin-bottom: 0.25rem; }
.option-desc { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.4; }
.cliche-area { margin-top: var(--spacing-lg); padding-top: var(--spacing-lg); border-top: 1px solid var(--border-color); }
.form-actions { display: flex; gap: var(--spacing-lg); justify-content: center; margin-top: var(--spacing-2xl); padding-top: var(--spacing-xl); border-top: 1px solid var(--border-color); }
.btn-primary, .btn-secondary { display: flex; align-items: center; gap: var(--spacing-sm); padding: var(--spacing-lg) var(--spacing-2xl); border: none; border-radius: var(--border-radius); font-size: 1.1rem; font-weight: 600; cursor: pointer; transition: all 0.2s ease; position: relative; overflow: hidden; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.btn-primary:active { transform: translateY(0); }
.btn-secondary { background: var(--bg-secondary); color: var(--text-primary); border: 2px solid var(--border-color); }
.btn-secondary:hover { background: var(--bg-muted); border-color: var(--text-secondary); transform: translateY(-1px); }
.loading-overlay { position: absolute; top: 0; left: 0; right: 0; bottom: 0; background: rgba(255, 255, 255, 0.95); backdrop-filter: blur(4px); display: flex; align-items: center; justify-content: center; z-index: 100; }
.loading-content { text-align: center; }
.loading-spinner { position: relative; width: 80px; height: 80px; margin: 0 auto var(--spacing-lg); }
.spinner-ring { position: absolute; width: 100%; height: 100%; border: 4px solid transparent; border-top: 4px solid var(--primary-color); border-radius: 50%; animation: spin 1s linear infinite; }
.spinner-ring:nth-child(2) { animation-delay: 0.1s; border-top-color: var(--secondary-color); }
.spinner-ring:nth-child(3) { animation-delay: 0.2s; border-top-color: var(--success-color); }
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }
.loading-text { font-size: 1.1rem; font-weight: 600; color: var(--text-primary); margin: 0; }
.results-container { background: var(--bg-secondary); border-top: 1px solid var(--border-color); }
.results-header { display: flex; justify-content: space-between; align-items: center; padding: var(--spacing-xl) var(--spacing-2xl); border-bottom: 1px solid var(--border-color); background: var(--bg-primary); }
.results-title h3 { font-size: 1.75rem; font-weight: 700; color: var(--text-primary); margin: 0; }
.results-actions { display: flex; gap: var(--spacing-sm); }
.action-btn { display: flex; align-items: center; gap: var(--spacing-xs); padding: var(--spacing-sm) var(--spacing-md); border: none; border-radius: var(--border-radius); font-size: 0.9rem; font-weight: 600; cursor: pointer; transition: all 0.2s ease; }
.excel-btn { background: var(--success-color); color: white; }
.print-btn { background: #3b82f6; color: white; }
.pdf-btn { background: var(--error-color); color: white; }
.action-btn:hover { transform: translateY(-1px); opacity: 0.9; }
.results-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: var(--spacing-lg); padding: var(--spacing-xl); }
.results-section { background: var(--bg-primary); border-radius: var(--border-radius); padding: var(--spacing-xl); border: 1px solid var(--border-color); box-shadow: var(--shadow-sm); }
.results-section h4 { font-size: 1.25rem; font-weight: 700; color: var(--text-primary); margin: 0 0 var(--spacing-lg) 0; padding-bottom: var(--spacing-sm); border-bottom: 2px solid var(--border-color); }
.results-table { width: 100%; border-collapse: collapse; }
.results-table th, .results-table td { padding: var(--spacing-md) 0; border-bottom: 1px solid var(--border-color); text-align: center; font-size: 0.95rem; }
.results-table th { font-weight: 600; color: var(--text-primary); }
.results-table td { color: var(--text-secondary); font-weight: 500; }
.results-table tr:last-child th, .results-table tr:last-child td { border-bottom: none; }
.total-row th, .total-row td { background: linear-gradient(135deg, var(--success-color), #059669); color: white; font-weight: 700; font-size: 1rem; }
.category-header th, .category-header td { background: var(--bg-muted); color: var(--text-primary); font-weight: 700; text-transform: uppercase; font-size: 0.85rem; letter-spacing: 0.5px; }
.message-overlay { position: fixed; top: var(--spacing-lg); right: var(--spacing-lg); z-index: 1000; pointer-events: none; }
.message-content { display: flex; align-items: center; gap: var(--spacing-sm); padding: var(--spacing-md) var(--spacing-lg); border-radius: var(--border-radius); box-shadow: var(--shadow-lg); font-weight: 600; animation: slideIn 0.3s ease; pointer-events: auto; }
.message-content.success { background: var(--success-color); color: white; }
.message-content.error { background: var(--error-color); color: white; }
.message-content.warning { background: var(--warning-color); color: white; }
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
.hidden { display: none !important; }
.fade-in { animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
@media (max-width: 1024px) {
    .results-grid { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
}
@media (max-width: 767px) {
    #uc-ultrasonic-calculator-container { padding: var(--spacing-sm); margin: 0; width: 100%; box-sizing: border-box; }
    .calculator-body { padding: var(--spacing-md); }
    .header-content { flex-direction: column; gap: var(--spacing-lg); text-align: center; padding: var(--spacing-xl) var(--spacing-lg); }
    .header-title h2 { font-size: 2rem; }
    .primary-grid { grid-template-columns: 1fr; }
    .options-grid { grid-template-columns: 1fr; }
    .form-actions { flex-direction: column; }
    .results-header { flex-direction: column; gap: var(--spacing-md); align-items: stretch; padding: var(--spacing-lg); }
    .results-actions { justify-content: center; }
    .results-grid { grid-template-columns: 1fr; padding: var(--spacing-lg); }
    .results-section { padding: var(--spacing-lg); }
    .action-btn { flex: 1; justify-content: center; }
    .dimensions-grid { grid-template-columns: repeat(2, 1fr); gap: var(--spacing-sm); }
    .dimensions-grid .form-group { grid-column: span 1; }
    .dimensions-grid .form-group:last-child:nth-child(odd) { grid-column: 1 / -1; }
    #material-print-options { grid-template-columns: 1fr; gap: var(--spacing-sm); }
    #material-print-options .form-group { grid-column: span 1; }
    .form-section .options-grid { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
    .form-section .options-grid .option-card, .form-section .options-grid .form-group { grid-column: span 1; }
    .form-group select, .form-group input[type="number"], .form-group input[type="text"] { width: 100%; box-sizing: border-box; }
}
@media (min-width: 768px) {
    .dimensions-grid { grid-template-columns: repeat(4, 1fr); }
    #material-print-options { grid-template-columns: repeat(3, 1fr); }
    .form-section .options-grid { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
}
@media (prefers-color-scheme: dark) {
    :root {
        --text-primary: #f9fafb; --text-secondary: #d1d5db; --text-muted: #9ca3af;
        --border-color: #374151; --bg-primary: #1f2937; --bg-secondary: #111827;
        --bg-muted: #374151;
    }
    .calculator-card { border-color: var(--border-color); }
    .loading-overlay { background: rgba(31, 41, 55, 0.95); }
}