/* ===== NAVIGATION BAR STYLES ===== */
.top-bar {
    position: sticky; top: 0; z-index: 1001;    
    display: flex; justify-content: space-between; align-items: center;
    padding: 10px 20px; background-color: #222; 
}
.logo-text, .navigation .nav-link, .nav-toggle { color: #fff; }
.nav-toggle { display: none; font-size: 1.5rem; background: none; border: none; cursor: pointer; }
.navigation .nav-menu { display: flex; list-style: none; margin: 0; padding: 0; align-items: center; }
.navigation .nav-link { padding: 10px 15px; text-decoration: none; font-weight: 600; display: block; }
.navigation .nav-link i { margin-left: 5px; transition: transform 0.3s ease; }
.nav-item-dropdown { position: relative; }
.dropdown-menu {
    display: none; position: absolute; top: 100%; left: 0;
    background-color: #fff; box-shadow: 0 8px 16px rgba(0,0,0,0.15); border-radius: 5px;
    z-index: 1000; min-width: 600px; padding: 20px;
}
.dropdown-menu a, .dropdown-menu h4 { color: #333; }
.dropdown-link:hover { background-color: #f1f1f1; }
.dropdown-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 20px; }
.nav-item-dropdown:hover > .dropdown-menu { display: block; }
@media (max-width: 992px) {
    .nav-toggle { display: block; }
    .navigation .nav-menu {
        display: none; flex-direction: column; position: absolute; top: 100%;
        left: 0; width: 100%; background-color: #fff; border-top: 1px solid #eee;
    }
    .navigation .nav-menu .nav-link { color: #333; }
    .navigation .nav-menu.show-menu { display: flex; }
    .navigation .nav-item { width: 100%; text-align: left; }
    .nav-item-dropdown > .nav-link { display: flex; justify-content: space-between; align-items: center; }
    .dropdown-menu {
        display: none; position: static; width: 100%; box-shadow: none; border-top: 1px solid #f0f0f0;
        padding: 10px 0 10px 30px; min-width: unset; background-color: #f9f9f9;
    }
    .dropdown-menu.show-submenu { display: block; }
    .nav-item-dropdown:hover > .dropdown-menu { display: none; }
    .nav-item-dropdown.active:hover > .dropdown-menu { display: block; }
    .nav-item-dropdown.active > .nav-link i { transform: rotate(180deg); }
}

body {
    background-color: #f5f7fa;
    color: #333;
    font-family: 'Nunito', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    line-height: 1.6;
}

.header {
    width: 100%;
    margin: 40px auto 0;
    padding: 0;
    text-align: center;
    border-bottom: none !important; 
}

.header h1, .header h2 {
    color: #333;
    padding: 0; 
}

.header h1 {
    margin-bottom: 5px; 
}

.header h2 {
    margin-bottom: 0; 
}

.excel-icon-color {
    color: #21a366; 
}

.intro-section,
.bio-section {
    width: 100%;
    margin: 0 auto 40px auto; 
    padding: 0 15px;
    line-height: 1.8; 
    font-size: 1.1rem;
    color: #333;
    text-align: center;
}

.intro-content,
.bio-content {
    display: block;
    overflow: visible;
    padding-top: 15px;
}

.tools-grid-section {
    padding: 0 5px 40px 5px;
    max-width: 100%;
    margin: 0 auto;
    text-align: center;
}

.tools-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 25px;
    margin-top: 30px;
}

.tool-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: #333;
    max-width: 120px;
}

.tool-logo {
    width: 100px;
    height: 100px;
    border-radius: 18px;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #fff;
    font-size: 2.5rem;
    text-decoration: none;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    margin-bottom: 10px;
}

.tool-logo[data-color='1'] { background-color: #5ac8fa; }
.tool-logo[data-color='2'] { background-color: #ff9500; }
.tool-logo[data-color='3'] { background-color: #34c759; }
.tool-logo[data-color='4'] { background-color: #ff2d55; }
.tool-logo[data-color='5'] { background-color: #af52de; }
.tool-logo[data-color='6'] { background-color: #5856d6; }
.tool-logo[data-color='7'] { background-color: #fc6d26; }
.tool-logo[data-color='8'] { background-color: #4a90e2; }
.tool-logo[data-color='9'] { background-color: #7ed321; }
.tool-logo[data-color='10'] { background-color: #bd10e0; }
.tool-logo[data-color='11'] { background-color: #f5a623; }
.tool-logo[data-color='12'] { background-color: #417505; }
.tool-logo[data-color='13'] { background-color: #0076a8; }
.tool-logo[data-color='14'] { background-color: #9013fe; }
.tool-logo[data-color='15'] { background-color: #f7b500; }
.tool-logo[data-color='16'] { background-color: #50e3c2; }
.tool-logo[data-color='17'] { background-color: #d0021b; }
.tool-logo[data-color='18'] { background-color: #064098; }
.tool-logo[data-color='19'] { background-color: #7b293e; }
.tool-logo[data-color='20'] { background-color: #27ae60; }

.tool-logo:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.4);
}

.tool-title {
    margin: 0;
    font-size: 0.8rem;
    font-weight: 600;
    text-align: center;
}

footer {
    background-color: #222;
    color: #fff;
    padding: 20px 5px;
    text-align: center;
    margin-top: 40px;
}

.social-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap; 
}

.social-links a {
    color: #fff;
    font-size: 1.5rem;
    margin: 5px 10px;
}

.disclaimer-note {
    margin-top: 2rem;
    padding: 0 1rem;
    font-size: .8rem;
    color: #777;
    max-width: 100%;
    margin-left: auto;
    margin-right: auto;
}

@media (max-width: 768px) {
    .tools-grid {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 15px;
    }
    .tool-logo {
        width: 80px;
        height: 80px;
        font-size: 2rem;
    }
    .tool-item {
        max-width: 100px;
    }
    
    .header {
        padding-left: 0;
        padding-right: 0;
    }
    .header h1, .header h2 {
        padding-left: 0;
        padding-right: 0;
    }
}

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --light-color: #ecf0f1;
    --dark-color: #2c3e50;
    --success-color: #2ecc71;
    --warning-color: #f39c12;
    --error-color: #e74c3c;
    font-size: 16px;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Nunito', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    color: #333;
    background-color: #f5f7fa;
    line-height: 1.6;
}
img, canvas { max-width: 100%; height: auto; }

.main-content-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.25rem;
    width: 100%;
    overflow-x: hidden;
}

.main-header {
    text-align: center;
    padding: 1rem 0;
    margin-bottom: 1.25rem;
    border-bottom: 1px solid #ddd;
}
.main-header h1 {
    color: var(--primary-color);
    font-size: clamp(1.5rem, 4vw, 1.8rem);
    margin-top: 0.5rem;
    margin-bottom: 0.5rem;
    font-weight: 800;
}
.main-header p {
    color: #7f8c8d;
    font-weight: 400;
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
}

.container {
    background-color: white;
    border-radius: 8px;
    padding: 1.5rem;
    margin-top: 1.5rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}
.container h2 {
    color: var(--primary-color);
    margin-top: 0;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 0.6rem;
    font-weight: 800;
}
.container h3 { color: var(--secondary-color); margin-top: 1.25rem; font-weight: 600; }
.container h4 { color: var(--primary-color); margin-top: 1rem; font-weight: 600; }
.container p, .container ul { line-height: 1.8; }
.container ul { padding-left: 1.25rem; }

.calculator-section { margin-top: 2rem; }

.tab {
    overflow: hidden;
    border: 1px solid #ddd;
    background-color: white;
    border-radius: 8px 8px 0 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}
.tab button {
    background-color: inherit;
    float: left;
    border: none;
    outline: none;
    cursor: pointer;
    padding: 0.8rem 1.25rem;
    transition: 0.3s;
    font-size: 1rem;
    color: var(--primary-color);
    font-weight: 600;
}
.tab button:hover { background-color: rgba(52, 152, 219, 0.1); }
.tab button.active { background-color: var(--secondary-color); color: white; }

.tabcontent {
    display: none;
    padding: 1.25rem;
    border: 1px solid #ddd;
    border-top: none;
    borderRadius: 0 0 8px 8px;
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.input-controls { margin-bottom: 2rem; }
.visualization-container { display: flex; flex-direction: column; }
.vis-controls { margin-bottom: 1rem; display: flex; gap: 0.5rem; align-items: center; }
.vis-controls label { font-weight: 600; color: var(--primary-color); }
.vis-toggle { background-color: var(--light-color); color: var(--primary-color); padding: 0.5rem 1rem; }
.vis-toggle.active { background-color: var(--secondary-color); color: white; }
.vis-toggle:hover { background-color: #bdc3c7; }
.vis-toggle.active:hover { background-color: #2980b9; }
#vectorCanvas {
    border: 1px solid #ddd;
    background-color: #fdfdfd;
    border-radius: 4px;
    width: 100%;
    height: 350px;
}

.dimension-input {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 0.8rem;
    padding: 1rem;
    border-radius: 8px;
    transition: background-color 0.3s;
    position: relative;
}
.dimension-input.error {
    background-color: rgba(231, 76, 60, 0.05);
    border: 1px solid var(--error-color);
}
.dimension-input label { color: var(--primary-color); font-weight: 600; margin: 0; }
.dimension-input input, .dimension-input select { font-family: 'Nunito', sans-serif; font-size: 1rem; }
.dimension-input input {
    margin: 0; padding: 0.5rem; width: 100px;
    border: 1px solid #ddd; border-radius: 4px;
    transition: border 0.3s, box-shadow 0.3s;
}
.dimension-input input.error, .montecarlo-input input.error, select.error {
    border-color: var(--error-color);
    box-shadow: 0 0 0 3px rgba(231, 76, 60, 0.3);
}
.dimension-input input:focus, .montecarlo-input input:focus, button:focus-visible {
    outline: none; border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.3);
}

button {
    background-color: var(--secondary-color); color: white;
    padding: 0.7rem 1.25rem; border: none; border-radius: 4px;
    cursor: pointer; margin: 5px; font-size: 1rem;
    transition: background-color 0.3s, box-shadow 0.3s;
    font-family: 'Nunito', sans-serif; font-weight: 600;
}
button:hover { background-color: #2980b9; }
button:disabled { background-color: #95a5a6; cursor: not-allowed; }
.button-green { background-color: var(--success-color); }
.button-green:hover { background-color: #27ae60; }
.button-red { background-color: var(--error-color); }
.button-red:hover { background-color: #c0392b; }
.button-yellow { background-color: var(--warning-color); }
.button-yellow:hover { background-color: #e67e22; }

.table-wrapper {
    overflow-x: auto;
    width: 100%;
    -webkit-overflow-scrolling: touch;
}
table {
    border-collapse: collapse; 
    width: 100%; 
    margin: 0;
    background-color: white; 
}
th, td { 
    border: 1px solid #ddd; 
    padding: 0.75rem; 
    text-align: left; 
    white-space: nowrap;
}
th { background-color: var(--primary-color); color: white; font-weight: 600; }
tr:nth-child(even) { background-color: #f8f9fa; }

.results {
    margin-top: 1.25rem; display: flex; justify-content: space-between;
    flex-wrap: wrap; gap: 1rem;
}
.result-method {
    margin-bottom: 1rem; padding: 1.25rem; background-color: white;
    border-radius: 8px; flex: 1; min-width: 48%;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05); border: 1px solid #eee;
}
#montecarlo-results.result-method {
    flex-basis: 100%; min-width: 100%; display: flex;
    align-items: center; gap: 1.25rem;
}
.montecarlo-data { flex: 0 0 40%; }
.montecarlo-chart-container { flex: 1 1 60%; height: 250px; }
.result-method h4 {
    color: var(--primary-color); margin-top: 0;
    border-bottom: 1px solid #eee; padding-bottom: 0.6rem; font-weight: 600;
}
.result-method p { margin-bottom: 0.6rem; color: var(--primary-color); }
.add-remove-btns { margin-bottom: 1.25rem; }

.montecarlo-input { margin: 1.25rem 0; display: flex; align-items: center; gap: 0.6rem; }
.montecarlo-input label { color: var(--primary-color); font-weight: 600; }
.montecarlo-input input { padding: 0.5rem; width: 120px; border: 1px solid #ddd; border-radius: 4px; }

.tolerance-input { display: flex; align-items: center; gap: 5px; }
.tolerance-input input { width: 80px; }

.distribution-params { 
    display: flex; 
    flex-wrap: wrap; 
    align-items: center; 
    gap: 5px; 
    padding: 5px 0 0 0; 
    width: 100%;
}

.calculation-block {
    border: 1px solid #ddd; border-radius: 8px; padding: 1.25rem;
    margin-bottom: 1.25rem; background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}
.history-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 1rem;
}
.history-logo {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    object-fit: cover;
}
.history-title {
    font-weight: 800;
    font-size: 1.2rem;
    color: var(--primary-color);
    margin: 0;
}

.history-content-wrapper {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 1.5rem;
    align-items: flex-start;
}

.history-input-data h4, .history-results-data h4 {
    font-weight: 800;
    margin: 0 0 0.6rem 0;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.export-section { margin-top: 2rem; padding-top: 1.25rem; border-top: 1px solid #eee; }

.badge {
    display: inline-block; padding: 4px 8px; border-radius: 4px;
    font-size: 0.8rem; font-weight: bold; color: white;
}
.badge-primary { background-color: var(--primary-color); }

footer { padding: 2rem 1.25rem; text-align: center; }
.disclaimer-note { margin-top: 2rem; padding: 0 1rem; font-size: 0.8rem; color: #777; max-width: 800px; margin-left: auto; margin-right: auto; }

.dist-info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}
.dist-info-card {
    padding: 1rem;
    border: 1px solid #ddd;
    border-radius: 8px;
    background-color: #f9f9f9;
}
.dist-info-card h5 {
    margin-top: 0;
    color: var(--secondary-color);
    font-size: 1rem;
}
.dist-info-card p {
    font-size: 0.9rem;
    margin: 0;
}

.sign-selector {
    display: flex;
    align-items: center;
    gap: 5px;
}
.sign-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid var(--secondary-color);
    background-color: white;
    color: var(--secondary-color);
}
.sign-btn.active {
    background-color: var(--secondary-color);
    color: white;
}
.sign-btn:hover:not(.active) {
    background-color: rgba(52, 152, 219, 0.1);
}

.error-message {
    color: var(--error-color);
    font-size: 0.8rem;
    margin-top: 5px;
    display: none;
}
.error-message.show {
    display: block;
}

.delete-dimension-btn {
    position: absolute;
    right: 10px;
    top: 10px;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s;
    border: none;
    background-color: var(--error-color);
    color: white;
}
.delete-dimension-btn:hover {
    background-color: #c0392b;
    transform: scale(1.1);
}

@media (min-width: 769px) {
    .history-content-wrapper {
        grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
    }
}

@media (max-width: 992px) {
     #montecarlo-results.result-method { flex-direction: column; align-items: stretch; }
    .montecarlo-chart-container { margin-top: 1.25rem; }
}

@media (max-width: 768px) {
    .dimension-input { flex-direction: column; align-items: flex-start; }
    .results { flex-direction: column; }
    .result-method { min-width: 100%; }
    .delete-dimension-btn {
        position: relative;
        right: auto;
        top: auto;
        margin-top: 10px;
        align-self: flex-end;
    }
}

@media (max-width: 480px) {
    .container, .calculation-block, .tabcontent { padding: 1rem; }
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: #7f8c8d;
}
.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: #bdc3c7;
}
.empty-state p {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

/* ===== VALIDATION STYLES ===== */
.validation-feedback {
    margin-top: 10px;
    font-size: 0.85rem;
    width: 100%;
}

.validation-error-message {
    color: #e74c3c;
    margin: 5px 0;
    display: flex;
    align-items: center;
    gap: 5px;
}

.validation-warning-message {
    color: #f39c12;
    margin: 5px 0;
    display: flex;
    align-items: center;
    gap: 5px;
}

.validation-success-message {
    color: #27ae60;
    margin: 5px 0;
    display: flex;
    align-items: center;
    gap: 5px;
}

.dimension-input.validation-error {
    border-left: 4px solid #e74c3c;
    background-color: rgba(231, 76, 60, 0.05);
}

.dimension-input.validation-warning {
    border-left: 4px solid #f39c12;
    background-color: rgba(243, 156, 18, 0.05);
}