/* ===================================================================
   pH Calculator Styles
   Created: 2025-01-13
   Purpose: Calculator-specific styles for pH Calculator
   =================================================================== */

/* ===================================================================
   Action Buttons Grid (MANDATORY for 4-button layout)
   =================================================================== */
.action-buttons-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

@media (max-width: 576px) {
    .action-buttons-grid {
        grid-template-columns: 1fr;
    }
}

/* ===================================================================
   pH Scale Visualization
   =================================================================== */
.ph-scale-container {
    position: relative;
    margin: 20px 0;
    padding: 15px;
}

.ph-scale {
    background: linear-gradient(to right,
        #ff0000 0%,    /* Red pH 0 - Strong Acid */
        #ff7f00 21%,   /* Orange pH 3 */
        #ffff00 50%,   /* Yellow pH 7 - Neutral */
        #00ff00 71%,   /* Green pH 10 */
        #0000ff 100%   /* Blue pH 14 - Strong Base */
    );
    height: 40px;
    border-radius: 8px;
    position: relative;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.ph-scale-labels {
    display: flex;
    justify-content: space-between;
    margin-top: 8px;
    font-size: 0.85rem;
    color: #4a5568;
}

.ph-indicator {
    position: absolute;
    top: -10px;
    width: 3px;
    height: 60px;
    background: #000;
    transition: left 0.3s ease;
    z-index: 2;
}

.ph-indicator::before {
    content: '';
    position: absolute;
    top: -8px;
    left: -6px;
    width: 0;
    height: 0;
    border-left: 7.5px solid transparent;
    border-right: 7.5px solid transparent;
    border-top: 10px solid #000;
}

.ph-value-display {
    position: absolute;
    top: -35px;
    left: -20px;
    background: #000;
    color: #fff;
    padding: 4px 8px;
    border-radius: 4px;
    font-weight: 600;
    font-size: 0.9rem;
    white-space: nowrap;
}

/* ===================================================================
   Chemical Formula Display
   =================================================================== */
.chem-formula {
    font-family: 'Courier New', monospace;
    background: #f7fafc;
    padding: 8px 12px;
    border-radius: 4px;
    display: inline-block;
    border: 1px solid #e2e8f0;
    margin: 4px 0;
}

.chem-formula sub {
    font-size: 0.75em;
    vertical-align: sub;
}

.chem-formula sup {
    font-size: 0.7em;
    vertical-align: super;
}

/* ===================================================================
   Titration Curve Chart Container
   =================================================================== */
.titration-curve-container {
    background: white;
    padding: 20px;
    border-radius: 12px;
    margin: 15px 0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.chart-container {
    position: relative;
    height: 350px;
    width: 100%;
}

@media (max-width: 768px) {
    .chart-container {
        height: 280px;
    }
}

/* ===================================================================
   Indicator Color Samples
   =================================================================== */
.indicator-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
    margin-top: 15px;
}

.indicator-item {
    display: flex;
    align-items: center;
    padding: 12px;
    background: #f7fafc;
    border-radius: 8px;
    border: 1px solid #e2e8f0;
}

.indicator-sample {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: inline-block;
    border: 2px solid #cbd5e0;
    margin-right: 12px;
    flex-shrink: 0;
}

.indicator-info {
    flex-grow: 1;
}

.indicator-name {
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 4px;
}

.indicator-range {
    font-size: 0.85rem;
    color: #718096;
}

/* Indicator color presets */
.indicator-phenolphthalein {
    background: linear-gradient(to right, transparent 50%, #ff69b4 50%);
}

.indicator-methyl-orange {
    background: linear-gradient(to right, #ff0000 50%, #ff8c00 50%);
}

.indicator-bromothymol-blue {
    background: linear-gradient(to right, #ffff00 50%, #0000ff 50%);
}

.indicator-litmus {
    background: linear-gradient(to right, #ff0000 50%, #0000ff 50%);
}

/* ===================================================================
   Calculation Steps Container
   =================================================================== */
.steps-container {
    margin-top: 20px;
}

.step-item {
    background: #f7fafc;
    border-left: 4px solid #667eea;
    padding: 15px;
    margin-bottom: 12px;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.step-item:hover {
    background: #edf2f7;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.step-title {
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
}

.step-number {
    display: inline-block;
    width: 28px;
    height: 28px;
    background: #667eea;
    color: white;
    border-radius: 50%;
    text-align: center;
    line-height: 28px;
    margin-right: 10px;
    font-size: 0.9rem;
    font-weight: 600;
}

.step-formula {
    font-size: 1.05rem;
    margin: 10px 0;
    padding: 10px;
    background: white;
    border-radius: 4px;
    overflow-x: auto;
}

.step-result {
    color: #48bb78;
    font-weight: 600;
    margin-top: 8px;
    padding: 8px 12px;
    background: #f0fff4;
    border-radius: 4px;
    border-left: 3px solid #48bb78;
}

/* ===================================================================
   Result Display Enhancements
   =================================================================== */
.result-item {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 15px;
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.2);
}

.result-label {
    font-size: 0.9rem;
    opacity: 0.9;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.result-value {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 5px;
}

.result-unit {
    font-size: 0.95rem;
    opacity: 0.85;
}

.result-secondary {
    background: rgba(255, 255, 255, 0.15);
    padding: 12px 15px;
    border-radius: 8px;
    margin-top: 10px;
    font-size: 0.9rem;
}

/* ===================================================================
   Acid/Base Type Selection
   =================================================================== */
.acid-base-selector {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 10px;
    margin: 15px 0;
}

.type-option {
    padding: 12px;
    background: white;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.type-option:hover {
    border-color: #667eea;
    background: #f7fafc;
}

.type-option.active {
    border-color: #667eea;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-weight: 600;
}

/* ===================================================================
   Buffer Zone Highlighting
   =================================================================== */
.buffer-zone-indicator {
    margin-top: 15px;
    padding: 12px;
    border-radius: 8px;
    border-left: 4px solid #48bb78;
    background: #f0fff4;
}

.buffer-zone-indicator.poor {
    border-left-color: #f56565;
    background: #fff5f5;
}

.buffer-zone-indicator.optimal {
    border-left-color: #48bb78;
    background: #f0fff4;
}

.buffer-zone-text {
    font-size: 0.9rem;
    color: #2d3748;
}

/* ===================================================================
   ICE Table Display
   =================================================================== */
.ice-table {
    width: 100%;
    border-collapse: collapse;
    margin: 15px 0;
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.ice-table th,
.ice-table td {
    padding: 12px;
    text-align: center;
    border: 1px solid #e2e8f0;
}

.ice-table th {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-weight: 600;
}

.ice-table tr:nth-child(even) {
    background: #f7fafc;
}

.ice-table .row-label {
    font-weight: 600;
    background: #edf2f7;
    color: #2d3748;
}

/* ===================================================================
   Preset Selector Enhancement
   =================================================================== */
.preset-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 10px;
    margin: 15px 0;
}

.preset-button {
    padding: 10px 12px;
    background: white;
    border: 2px solid #e2e8f0;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: left;
    font-size: 0.9rem;
}

.preset-button:hover {
    border-color: #667eea;
    background: #f7fafc;
    transform: translateY(-2px);
}

.preset-button .chem-name {
    font-weight: 600;
    color: #2d3748;
    display: block;
    margin-bottom: 4px;
}

.preset-button .chem-pka {
    font-size: 0.8rem;
    color: #718096;
}

/* ===================================================================
   Warning and Error Messages
   =================================================================== */
.warning-box {
    padding: 12px 15px;
    margin: 15px 0;
    border-radius: 8px;
    border-left: 4px solid #f59e0b;
    background: #fffbeb;
    display: flex;
    align-items: flex-start;
}

.warning-box i {
    margin-right: 10px;
    color: #f59e0b;
    margin-top: 2px;
}

.error-box {
    padding: 12px 15px;
    margin: 15px 0;
    border-radius: 8px;
    border-left: 4px solid #f56565;
    background: #fff5f5;
    display: flex;
    align-items: flex-start;
}

.error-box i {
    margin-right: 10px;
    color: #f56565;
    margin-top: 2px;
}

/* ===================================================================
   Responsive Adjustments
   =================================================================== */
@media (max-width: 768px) {
    .result-value {
        font-size: 1.5rem;
    }

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

    .indicator-list {
        grid-template-columns: 1fr;
    }

    .ice-table {
        font-size: 0.85rem;
    }

    .ice-table th,
    .ice-table td {
        padding: 8px 6px;
    }
}

/* ===================================================================
   Toggle Button for Steps
   =================================================================== */
.toggle-steps-btn {
    width: 100%;
    padding: 12px;
    background: white;
    border: 2px solid #667eea;
    border-radius: 8px;
    color: #667eea;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.toggle-steps-btn:hover {
    background: #667eea;
    color: white;
}

.toggle-steps-btn i {
    margin-left: 8px;
    transition: transform 0.2s ease;
}

.toggle-steps-btn.active i {
    transform: rotate(180deg);
}

/* ===================================================================
   Equivalence Point Marker
   =================================================================== */
.equivalence-point-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px;
    background: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
    color: white;
    border-radius: 8px;
    margin-top: 15px;
}

.equivalence-label {
    font-weight: 600;
    font-size: 1.1rem;
}

.equivalence-values {
    text-align: right;
}

.equivalence-volume,
.equivalence-ph {
    display: block;
    font-size: 0.9rem;
}

/* ===================================================================
   Keyboard Shortcuts Info
   =================================================================== */
.keyboard-shortcuts {
    display: none;
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: rgba(0, 0, 0, 0.9);
    color: white;
    padding: 15px 20px;
    border-radius: 8px;
    font-size: 0.85rem;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.keyboard-shortcuts.show {
    display: block;
}

.shortcut-item {
    margin: 5px 0;
}

.shortcut-key {
    background: #4a5568;
    padding: 2px 6px;
    border-radius: 3px;
    margin-right: 8px;
    font-family: monospace;
}

/* ===================================================================
   Loading Spinner for Calculations
   =================================================================== */
.calculation-spinner {
    display: none;
    text-align: center;
    padding: 20px;
}

.calculation-spinner.active {
    display: block;
}

.spinner {
    border: 4px solid #f3f4f6;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}