:root {
    --title-text-color: #f9f9f9;
    --primary-text-color: #333;
    --secondary-text-color: black;
    --primary-background-color: #eee;
    --secondary-background-color: white;
    --primary-button-color: #5B7C99;
    --primary-button-hover-color: #4A6580;
    --primary-button-border-color: #4A6580;
    --secondary-button-color: #fff;
    --secondary-button-border-color: #ccc;
    --input-background-color: white;
    --usual-border-size: 1px;
    --input-placeholder-color: grey;
    --secondary-hover-button-background-color: #ebebeb;
    --dialog-background-color: #fff;
}

[data-dark-mode] {
    --title-text-color: #d9d9da;
    --primary-text-color: #eee;
    --secondary-text-color: #d9d9da;
    --primary-background-color: #202124;
    --secondary-background-color: #202124;
    --primary-button-color: #5B7C99;
    --primary-button-hover-color: #6B8CAA;
    --primary-button-border-color: #5B7C99;
    --secondary-button-color: #444;
    --secondary-button-border-color: #444;
    --input-background-color: #303136;
    --usual-border-size: 0;
    --input-placeholder-color: #aaa;
    --secondary-hover-button-background-color: #666;
    --dialog-background-color: #303136;
}

html[data-dark-mode] #theme-toggle-moon { display: none; }
html:not([data-dark-mode]) #theme-toggle-sun { display: none; }
html[data-dark-mode] #theme-toggle-sun { display: block; }
html:not([data-dark-mode]) #theme-toggle-moon { display: block; }

#theme-toggle-sun, #theme-toggle-moon { color: #5B7C99; }

#dark-mode-toggle {
    background: #e3e8ef;
    padding: 8px;
    border: none;
    border-radius: 8px;
    margin: 10px;
    position: absolute;
    right: 0;
    cursor: pointer;
    transition: all 0.2s ease;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}

#dark-mode-toggle:hover { 
    background: #d4dce6;
    transform: translateY(-1px);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
}

#dark-mode-toggle:active {
    transform: scale(0.95);
}

html[data-dark-mode] #dark-mode-toggle { background: #3d4c5e; }
html[data-dark-mode] #dark-mode-toggle:hover { 
    background: #4d5f73;
    transform: translateY(-1px);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    width: 100%;
    text-align: center;
    background: var(--primary-background-color);
    color: var(--secondary-text-color);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

.logo {
    background-color: #5B7C99;
    background-image: linear-gradient(135deg, #4A6580, #6B8CAA);
    height: 90px;
    position: relative;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

#titleHeader {
    margin: 0;
}

#logo {
    display: block;
    margin: 0 auto;
    color: var(--title-text-color);
    font-size: 40px;
    font-weight: bold;
    text-decoration: none;
    text-shadow: 1px 1px grey;
    padding-top: 20px;
    width: fit-content;
}

.mainContent {
    padding: 2em 1.5em;
    background: var(--primary-background-color);
    min-height: calc(100vh - 90px);
    max-width: 1700px;
    margin: 0 auto;
}

.top-section {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    margin-bottom: 20px;
    margin-top: 10px;
    gap: 20px;
}

.controls {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
    justify-self: start;
}

#clearButton {
    justify-self: end;
}

.btn-success {
    margin-bottom: 0;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    margin: 0;
    font-size: 14px;
    font-weight: 500;
    line-height: 1.5;
    text-align: center;
    white-space: nowrap;
    cursor: pointer;
    border: none;
    border-radius: 6px;
    user-select: none;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: none;
    min-height: 40px;
}

.btn:active {
    transform: scale(0.98);
}

.btn-default {
    color: var(--secondary-text-color);
    background-color: var(--secondary-button-color);
    border: 1px solid var(--secondary-button-border-color);
}

.btn-default:hover {
    background-color: var(--secondary-hover-button-background-color);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.btn-success {
    color: white;
    background: linear-gradient(135deg, #5B7C99, #4A6580);
    border: none;
    font-size: 16px;
    font-weight: 600;
    padding: 14px 40px;
    box-shadow: 0 4px 14px rgba(91, 124, 153, 0.4);
    letter-spacing: 0.5px;
    min-height: 50px;
}

.btn-success:hover {
    background: linear-gradient(135deg, #4A6580, #3B5266);
    box-shadow: 0 6px 20px rgba(91, 124, 153, 0.5);
    transform: translateY(-2px);
}

.textarea-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 20px 0;
    max-width: 100%;
}

.textarea-wrapper {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.textarea-label {
    font-size: 13px;
    font-weight: 600;
    color: var(--primary-text-color);
    opacity: 0.8;
    text-align: left;
    padding-left: 4px;
}

textarea {
    width: 100%;
    min-height: 500px;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 13px;
    padding: 16px;
    border: 2px solid transparent;
    color: var(--primary-text-color);
    background: var(--input-background-color);
    resize: vertical;
    border-radius: 5px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: all 0.2s ease;
}

textarea:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

textarea:focus {
    outline: none;
    box-shadow: 0 4px 16px rgba(91, 124, 153, 0.25);
    border-color: var(--primary-button-color);
}

::placeholder {
    color: var(--input-placeholder-color);
}

#comparisonWrapper {
    margin: 20px auto;
    display: none;
    animation: fadeIn 0.3s ease;
    border-radius: 5px;
    overflow: hidden;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
}

html[data-dark-mode] #comparisonWrapper {
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

#comparisonWrapper + .top-section {
    margin-top: 30px;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.text-compare {
    font-size: 13px;
    border: 1px solid #ababab;
    background: white;
    line-height: normal;
    width: 100%;
    margin: 0 auto;
    border-collapse: collapse;
}

html[data-dark-mode] .text-compare {
    background: var(--input-background-color);
    border-color: #5d5d5d;
}

.text-compare td {
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    padding: 4px 8px;
    vertical-align: top;
    text-align: left;
}

/* Vertical separator between the two text columns */
.text-compare td:nth-child(3) {
    border-right: 2px solid #d0d0d0;
    padding-right: 12px;
}

html[data-dark-mode] .text-compare td:nth-child(3) {
    border-right-color: #555;
}

.line_number {
    width: 40px;
    background: #f9f9f9;
    text-align: right;
    user-select: none;
    color: #666;
    font-size: 11px;
    padding: 4px 8px;
    border-right: 1px solid #ddd;
}

html[data-dark-mode] .line_number {
    background: var(--input-background-color);
    color: #aaa;
    border-right-color: #555;
}

.marker {
    width: 30px;
    text-align: center;
    user-select: none;
    font-weight: bold;
    font-size: 14px;
}

.added {
    background: #d4f4dd;
}

.marker.added {
    color: #2d8659;
    background: #a8e6c1;
}

.removed {
    background: #ffd7d5;
}

.marker.removed {
    color: #c73b35;
    background: #ffb3b0;
}

.changed {
    background: #d5e5f5;
}

html[data-dark-mode] .added {
    background: #2d5a3a;
}

html[data-dark-mode] .marker.added {
    color: #7ad99e;
    background: #3d6a4a;
}

html[data-dark-mode] .removed {
    background: #6e3838;
}

html[data-dark-mode] .marker.removed {
    color: #ff9d9a;
    background: #8a4848;
}

html[data-dark-mode] .changed {
    background: #2d4a5e;
}

.lineContent {
    width: 50%;
    word-wrap: break-word;
    white-space: pre-wrap;
}

html[data-dark-mode] .lineContent {
    color: var(--title-text-color);
}

.messageForUser {
    background-color: var(--primary-button-color);
    border: 1px solid var(--primary-button-border-color);
    color: var(--title-text-color);
    font-size: 15px;
    margin: 15px auto;
    padding: 12px 50px;
    display: none;
    border-radius: 8px;
    max-width: 600px;
    box-shadow: 0 2px 8px rgba(91, 124, 153, 0.3);
    animation: fadeIn 0.3s ease;
}

.dropdown {
    position: relative;
    display: inline-block;
}

.dropdown-content {
    display: none;
    position: absolute;
    background-color: var(--dialog-background-color);
    min-width: 240px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
    z-index: 1000;
    border-radius: 10px;
    border: 1px solid rgba(0, 0, 0, 0.08);
    margin-top: 0;
    padding: 6px;
    left: 0;
    top: calc(100% + 4px);
    opacity: 0;
    transform: translateY(-10px);
    transition: opacity 0.2s ease, transform 0.2s ease;
    text-align: left;
}

.dropdown-content.show {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

html[data-dark-mode] .dropdown-content {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    border-color: rgba(255, 255, 255, 0.1);
}

.dropdown-content a {
    color: var(--secondary-text-color);
    padding: 10px 16px;
    text-decoration: none;
    display: block;
    transition: all 0.15s ease;
    border-radius: 6px;
    font-size: 14px;
}

.dropdown-content a:hover {
    background-color: var(--primary-button-color);
    color: white;
    transform: translateX(4px);
}

.diff_title {
    padding: 1em;
    background: linear-gradient(90deg, #f5f5f5, #fafafa);
    font-size: 15px;
    font-weight: 600;
    color: #444;
    text-align: left;
}

html[data-dark-mode] .diff_title {
    background: linear-gradient(90deg, #2a2a2e, #303136);
    color: var(--title-text-color);
}

.diff_title td {
    font-weight: 600;
}

@media only screen and (max-width: 768px) {
    .textarea-container {
        grid-template-columns: 1fr;
    }

    .logo {
        height: auto;
        padding-bottom: 10px;
    }

    #logo {
        font-size: 30px;
    }

    .top-section {
        grid-template-columns: 1fr;
        gap: 15px;
        text-align: center;
    }

    .controls {
        justify-content: center;
        justify-self: center;
        gap: 8px;
    }

    #clearButton {
        justify-self: center;
    }

    .btn-success {
        padding: 12px 30px;
        font-size: 15px;
        margin-bottom: 0;
    }

    .btn {
        padding: 8px 16px;
        font-size: 13px;
        min-height: 36px;
    }
}