/* Theme Variables */
:root {
    /* Light theme (default) */
    --primary-color: #1a3a5f;
    --secondary-color: #4d7ea8;
    --accent-color: #f39237;
    --accent-color-rgb: 243, 146, 55; /* RGB values for accent color */
    --light-color: #f5f5f5;
    --dark-color: #333;
    --bg-color: #f5f5f5;
    --text-color: #333;
    --card-bg: #fff;
    --card-border: #ddd;
    --highlight-bg: rgba(243, 146, 55, 0.2);
    --success-color: #2ecc71;
    --error-color: #e74c3c;
}

/* Dark theme */
[data-theme="dark"] {
    --primary-color: #2c5282;
    --secondary-color: #3182ce;
    --accent-color: #f6ad55;
    --accent-color-rgb: 246, 173, 85; /* RGB values for accent color in dark mode */
    --light-color: #1a202c;
    --dark-color: #e2e8f0;
    --bg-color: #1a202c;
    --text-color: #e2e8f0;
    --card-bg: #2d3748;
    --card-border: #4a5568;
    --highlight-bg: rgba(246, 173, 85, 0.2);
}

/* Theme Toggle Styles */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
}

.theme-toggle button {
    background: transparent;
    border: none;
    color: var(--accent-color);
    font-size: 1.5rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.3s, transform 0.3s;
}

.theme-toggle button:hover {
    background-color: rgba(0, 0, 0, 0.1);
    transform: rotate(15deg);
}

/* Show/hide the sun/moon/desktop icons based on theme */
.fa-sun, .fa-moon, .fa-desktop {
    display: none;
}

[data-theme="light"] .theme-toggle .fa-sun,
[data-theme="dark"] .theme-toggle .fa-moon {
    display: inline-block;
}

/* General Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

/* Header Styles */
header {
    background-color: var(--primary-color);
    color: white;
    text-align: center;
    padding: 2rem 0;
    position: relative;
    transition: background-color 0.3s;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

/* Language Selector Styles */
.language-selector {
    margin-top: 1rem;
    display: flex;
    justify-content: center;
    gap: 0.5rem;
}

.lang-btn {
    padding: 0.5rem 1rem;
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.lang-btn.active {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
    font-weight: bold;
}

.lang-btn:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

/* Language specific display */
[data-lang="en"], [data-lang="vi"] {
    display: none;
}

.lang-en [data-lang="en"],
.lang-vi [data-lang="vi"] {
    display: block;
}

.lang-en [data-lang="vi"],
.lang-vi [data-lang="en"] {
    display: none;
}

/* Special handling for title elements */
title[data-lang] {
    display: none;
}

nav.lang-en a[data-lang="en"],
nav.lang-vi a[data-lang="vi"],
.lang-en button[data-lang="en"],
.lang-vi button[data-lang="vi"],
.lang-en span[data-lang="en"],
.lang-vi span[data-lang="vi"],
.lang-en option[data-lang="en"],
.lang-vi option[data-lang="vi"],
.lang-en li[data-lang="en"],
.lang-vi li[data-lang="en"] {
    display: inline-block;
}

nav.lang-en a[data-lang="vi"],
nav.lang-vi a[data-lang="en"],
.lang-en button[data-lang="vi"],
.lang-vi button[data-lang="en"],
.lang-en span[data-lang="vi"],
.lang-vi span[data-lang="en"],
.lang-en option[data-lang="vi"],
.lang-vi option[data-lang="en"],
.lang-en li[data-lang="vi"],
.lang-vi li[data-lang="en"] {
    display: none;
}

/* Navigation Styles */
nav {
    background-color: var(--secondary-color);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background-color 0.3s;
}

nav ul {
    display: flex;
    list-style: none;
    justify-content: center;
}

nav a {
    display: block;
    color: white;
    text-decoration: none;
    padding: 1rem 1.5rem;
    transition: background-color 0.3s;
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

nav a.active {
    background-color: var(--accent-color);
    font-weight: bold;
}

/* Main Content Styles */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Cipher Section Styles */
.cipher-section {
    margin-bottom: 4rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--secondary-color);
}

.cipher-section:last-child {
    border-bottom: none;
}

.cipher-section h2 {
    color: var(--primary-color);
    font-size: 2rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 3px solid var(--accent-color);
    display: inline-block;
}

.description {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
}

/* Formula Styles */
.formula-container {
    display: flex;
    gap: 2rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.formula {
    background-color: var(--card-bg);
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    min-width: 300px;
    transition: background-color 0.3s;
}

.formula h3 {
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
}

/* Rules Styles */
.rules {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    margin-bottom: 1.5rem;
    transition: background-color 0.3s;
}

.rules h3 {
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
}

.rules ol {
    padding-left: 1.5rem;
}

.rules li {
    margin-bottom: 0.5rem;
}

/* Cipher Tool Styles */
.cipher-tool {
    background-color: var(--card-bg);
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    overflow: hidden;
    transition: background-color 0.3s;
}

.input-container {
    display: flex;
    flex-direction: column;
}

.output-container {
    display: flex;
    flex-direction: column;
    overflow: visible;
    width: 100%;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
}

.form-group textarea, 
.form-group input[type="text"],
.form-group input[type="number"],
.form-group select {
    width: 100%;
    padding: 0.8rem;
    border: 1px solid var(--card-border);
    border-radius: 4px;
    font-size: 1rem;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

.form-group textarea {
    resize: vertical;
    height: 120px;
}

.button-group {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.button-group button {
    padding: 0.8rem 1.5rem;
    background-color: var(--secondary-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

.button-group button:hover {
    background-color: var(--primary-color);
}

.output-container textarea {
    width: 100%;
    height: 120px;
    padding: 0.8rem;
    border: 1px solid var(--card-border);
    border-radius: 4px;
    resize: vertical;
    margin-bottom: 1rem;
    font-size: 1rem;
    font-family: monospace;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

/* Example Styles */
.example {
    background-color: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 1.5rem;
    transition: background-color 0.3s, border-color 0.3s;
}

.example h3 {
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.example-content {
    margin: 1rem 0;
}

.example-row {
    display: flex;
    margin-bottom: 0.5rem;
    flex-wrap: wrap;
    align-items: center;
}

.example-row .label {
    font-weight: bold;
    margin-right: 1rem;
    min-width: 100px;
}

.example-row .text {
    padding: 0.3rem 0.6rem;
    background-color: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 4px;
    margin-right: 0.5rem;
    font-family: monospace;
    transition: background-color 0.3s, border-color 0.3s;
}

.example button {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.3s;
}

.example button:hover {
    background-color: #e07f1f;
}

/* Explanation Styles */
.explanation-container {
    background-color: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    transition: background-color 0.3s, border-color 0.3s;
}

.explanation-container h4 {
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
    border-bottom: 1px solid var(--card-border);
    padding-bottom: 0.5rem;
    font-size: 1.1rem;
}

.explanation-content {
    font-size: 0.95rem;
    line-height: 1.5;
}

.explanation-content .step {
    margin-bottom: 0.8rem;
    padding-left: 1.2rem;
    position: relative;
}

.explanation-content .step::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: bold;
}

.explanation-content .letter {
    display: inline-block;
    background-color: var(--highlight-bg);
    border: 1px solid rgba(77, 126, 168, 0.3);
    border-radius: 3px;
    padding: 0.1rem 0.3rem;
    margin: 0 0.1rem;
    font-family: monospace;
    font-weight: bold;
}

.explanation-content .arrow {
    color: var(--accent-color);
    margin: 0 0.3rem;
    font-weight: bold;
}

.explanation-content .formula {
    font-family: monospace;
    background-color: rgba(0, 0, 0, 0.05);
    padding: 0.2rem 0.4rem;
    border-radius: 3px;
    margin: 0 0.2rem;
}

/* Show explanation only when there's content */
.explanation-container {
    display: none;
}

.explanation-container.has-content {
    display: block;
}

/* Grid and Table Styles */
.cipher-table, 
.playfair-grid, 
.polybius-square, 
.tabula-recta {
    margin-top: 1rem;
    overflow: auto;
}

/* Caesar Cipher Table Styles (Table 4.2) */
.cipher-table table {
    width: 100%;
    border-collapse: collapse;
    border: 2px solid var(--primary-color);
    margin: 1rem 0;
    font-family: monospace;
    font-size: 0.85rem;
    table-layout: fixed;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    transition: border-color 0.3s;
}

.cipher-table th, 
.cipher-table td {
    border: 1px solid var(--secondary-color);
    text-align: center;
    padding: 0.25rem 0.12rem;
    width: auto;
    transition: border-color 0.3s, background-color 0.3s;
}

.cipher-table th {
    background-color: var(--secondary-color);
    color: white;
    font-weight: bold;
    transition: background-color 0.3s;
}

.cipher-table tr:first-child {
    border-bottom: 2px solid var(--primary-color);
    transition: border-color 0.3s;
}

.cipher-table tr:nth-child(2) {
    background-color: var(--bg-color);
    transition: background-color 0.3s;
}

.cipher-table th:first-child {
    width: 50px;
    background-color: var(--primary-color);
    transition: background-color 0.3s;
}

.cipher-table td.highlight {
    background-color: var(--accent-color);
    color: white;
    font-weight: bold;
    transition: background-color 0.3s;
}

.caesar-table-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 1rem 0;
    padding: 0.7rem 0.3rem;
    background-color: var(--card-bg);
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    overflow-x: visible;
    max-width: none;
    width: 100%;
    transition: background-color 0.3s;
}

.caesar-table-title {
    color: var(--secondary-color);
    margin-bottom: 0.7rem;
    font-size: 1.05rem;
    text-align: center;
}

.playfair-grid-container, 
.polybius-square-container, 
.tabula-recta-container {
    margin-top: 1rem;
    background-color: var(--card-bg);
    border-radius: 8px;
    padding: 1rem;
    transition: background-color 0.3s;
}

.playfair-grid-container h4, 
.polybius-square-container h4, 
.tabula-recta-container h4 {
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
}

.playfair-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1px;
    width: fit-content;
    margin: 0 auto;
}

.playfair-grid .cell {
    width: 40px;
    height: 40px;
    background-color: var(--bg-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    border: 1px solid var(--secondary-color);
    transition: background-color 0.3s, border-color 0.3s;
}

.playfair-grid .cell.ij-cell {
    background-color: rgba(var(--accent-color-rgb), 0.2);
    font-size: 0.9em; /* Slightly smaller font to fit both letters */
    border: 2px solid var(--accent-color);
}

.polybius-square {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 1px;
    width: fit-content;
    margin: 0 auto;
}

.polybius-square .cell {
    width: 40px;
    height: 40px;
    background-color: var(--bg-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    border: 1px solid var(--secondary-color);
    transition: background-color 0.3s, border-color 0.3s;
}

.polybius-square .header {
    background-color: var(--secondary-color);
    color: white;
    transition: background-color 0.3s;
}

.polybius-square .cell.highlight {
    background-color: var(--accent-color);
    color: white;
    transform: scale(1.1);
    box-shadow: 0 0 10px rgba(var(--accent-color-rgb), 0.7);
    z-index: 5;
    font-weight: bold;
}

.polybius-square .cell.ij-cell {
    background-color: rgba(var(--accent-color-rgb), 0.2);
    font-size: 0.9em; /* Slightly smaller font to fit both letters */
    border: 2px solid var(--accent-color);
}

.tabula-recta {
    display: grid;
    grid-template-columns: repeat(27, 30px);
    gap: 1px;
    overflow-x: auto;
    max-width: 100%;
}

.tabula-recta .cell {
    width: 30px;
    height: 30px;
    background-color: var(--bg-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    border: 1px solid var(--card-border);
    transition: background-color 0.3s, border-color 0.3s;
}

.tabula-recta .header {
    background-color: var(--secondary-color);
    color: white;
    position: sticky;
    top: 0;
    z-index: 1;
    transition: background-color 0.3s;
}

.tabula-recta .index {
    background-color: var(--secondary-color);
    color: white;
    position: sticky;
    left: 0;
    z-index: 2;
    transition: background-color 0.3s;
}

/* Footer Styles */
footer {
    background-color: var(--primary-color);
    color: white;
    text-align: center;
    padding: 1.5rem;
    margin-top: 2rem;
    transition: background-color 0.3s;
}

/* Responsive Adjustments */
@media (max-width: 900px) {
    .cipher-tool {
        grid-template-columns: 1fr;
    }
    
    .formula-container {
        flex-direction: column;
    }
    
    .example-row {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .example-row .label {
        margin-bottom: 0.5rem;
    }
    
    .cipher-table table {
        font-size: 0.65rem;
        width: 100%;
    }
    
    .cipher-table th, 
    .cipher-table td {
        padding: 0.15rem 0.02rem;
    }
}

@media (max-width: 600px) {
    nav ul {
        flex-direction: column;
    }
    
    nav a {
        text-align: center;
    }
    
    .theme-toggle {
        top: 10px;
        right: 10px;
    }
} 

/* Word Lookup Section */
.word-lookup-container {
    margin: 20px 0;
    padding: 20px;
    border: 2px solid var(--accent-color);
    border-radius: 8px;
    background-color: var(--card-bg);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.word-lookup-container h4 {
    font-size: 1.3rem;
    margin: 0 0 15px 0;
    color: var(--accent-color);
    text-align: center;
    border-bottom: 1px solid var(--card-border);
    padding-bottom: 10px;
}

.word-lookup-form {
    margin-bottom: 20px;
}

.word-lookup-form .form-group {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 15px;
    justify-content: center;
}

.word-lookup-form input {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-size: 1.1rem;
    min-width: 200px;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.word-lookup-form input:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px rgba(var(--accent-color-rgb), 0.2);
    outline: none;
}

.word-lookup-form .button-group {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    justify-content: center;
}

.word-lookup-form .button-group button {
    padding: 8px 15px;
    border: none;
    border-radius: 6px;
    background-color: var(--accent-color);
    color: white;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

.word-lookup-form .button-group button:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
}

.word-lookup-form .button-group button:active {
    transform: translateY(0);
}

.word-lookup-result {
    padding: 15px;
    background-color: var(--highlight-bg);
    border-radius: 6px;
    margin-top: 15px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.word-lookup-result p {
    margin: 5px 0;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
}

/* Ẩn kết quả tra cứu từng từ theo ngôn ngữ */
.lang-en .word-lookup-result p[data-lang="vi"],
.lang-vi .word-lookup-result p[data-lang="en"] {
    display: none;
}

.lang-en .word-lookup-result p[data-lang="en"],
.lang-vi .word-lookup-result p[data-lang="vi"] {
    display: flex;
}

.word-lookup-result span {
    font-weight: bold;
    margin-left: 10px;
    padding: 5px 10px;
    background-color: var(--card-bg);
    border-radius: 4px;
    color: var(--accent-color);
    min-width: 100px;
    display: inline-block;
    text-align: center;
}

/* Responsive for Word Lookup */
@media (max-width: 768px) {
    .word-lookup-form .form-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .word-lookup-form input {
        width: 100%;
    }
    
    .word-lookup-form .button-group {
        width: 100%;
        justify-content: space-between;
    }
} 

/* Table Type Selector */
.table-type-selector {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 15px;
    padding: 10px;
    border-radius: 5px;
    background-color: var(--bg-color);
}

.radio-container {
    display: flex;
    align-items: center;
    cursor: pointer;
    padding: 5px 10px;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.radio-container:hover {
    background-color: var(--highlight-bg);
}

.radio-container input[type="radio"] {
    margin-right: 8px;
    accent-color: var(--accent-color);
}

.radio-container .radio-text {
    color: var(--text-color);
}

/* Show/hide radio buttons based on language */
.lang-en .radio-container[data-lang="vi"],
.lang-vi .radio-container[data-lang="en"] {
    display: none;
} 

/* Digraph Processing Styles */
.digraph-processing-container {
    margin-top: 20px;
    border-top: 1px solid var(--card-border);
    padding-top: 15px;
}

.digraph-processing {
    font-family: monospace;
    background-color: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 6px;
    padding: 15px;
    margin: 10px 0;
    max-height: 250px;
    overflow-y: auto;
    line-height: 1.6;
}

.digraph-processing .digraph-item {
    margin-bottom: 10px;
    padding: 8px;
    border-radius: 4px;
    background-color: var(--card-bg);
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.digraph-processing .digraph-pair {
    display: inline-block;
    background-color: var(--highlight-bg);
    color: var(--text-color);
    padding: 2px 6px;
    border-radius: 3px;
    font-weight: bold;
    margin: 0 5px;
}

.digraph-processing .digraph-rule {
    color: var(--accent-color);
    font-weight: bold;
}

.digraph-processing .digraph-result {
    margin-left: 20px;
    padding-left: 10px;
    border-left: 2px solid var(--accent-color);
} 

/* Coordinate Helper Styles */
.coordinate-helper {
    margin-top: 20px;
    padding: 15px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--card-bg);
}

.coordinate-helper h4 {
    margin: 0 0 10px 0;
    color: var(--accent-color);
    font-size: 1.1rem;
}

.helper-input-group {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
}

.helper-input-group input {
    width: 60px;
    text-align: center;
    font-size: 1.2rem;
    padding: 8px;
    border: 1px solid var(--card-border);
    border-radius: 4px;
    background-color: var(--bg-color);
    color: var(--text-color);
    text-transform: uppercase;
}

.helper-input-group button {
    padding: 8px 15px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
}

.helper-input-group button:hover {
    background-color: var(--secondary-color);
}

.helper-result {
    padding: 10px;
    margin-top: 10px;
    border-radius: 4px;
    background-color: var(--highlight-bg);
    min-height: 40px;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
}

.helper-result.highlight {
    border: 2px solid var(--accent-color);
    animation: pulse 1s;
}

.helper-result .letter-coord {
    font-weight: bold;
    color: var(--accent-color);
    margin: 0 5px;
}

.helper-result .grid-position {
    background-color: var(--card-bg);
    padding: 3px 8px;
    border-radius: 3px;
    margin: 0 5px;
}

/* Polybius Square customization */
.size-controls {
    display: flex;
    align-items: center;
    gap: 10px;
}

#polybius-size {
    width: 60px;
    padding: 5px;
    border: 1px solid var(--secondary-color);
    border-radius: 4px;
}

.alphabet-suggestions {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin-top: 5px;
}

.alphabet-suggestions .suggestion {
    background-color: var(--card-bg);
    border: 1px solid var(--secondary-color);
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 0.85em;
    cursor: pointer;
    transition: all 0.2s;
}

.alphabet-suggestions .suggestion:hover {
    background-color: var(--secondary-color);
    color: white;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(var(--accent-color-rgb), 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(var(--accent-color-rgb), 0); }
    100% { box-shadow: 0 0 0 0 rgba(var(--accent-color-rgb), 0); }
} 

/* Key Sequence Container Styles */
.key-sequence-container {
    margin-top: 20px;
    padding: 15px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--card-bg);
}

.key-sequence-container h4 {
    margin: 0 0 10px 0;
    color: var(--accent-color);
    font-size: 1.1rem;
}

.key-sequence {
    background-color: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 6px;
    padding: 15px;
    max-height: 150px;
    overflow-y: auto;
    font-family: monospace;
    line-height: 1.6;
    white-space: pre-wrap;
    word-break: break-all;
}

.key-sequence .key-item {
    display: inline-block;
    background-color: var(--highlight-bg);
    padding: 3px 6px;
    margin: 2px;
    border-radius: 3px;
    font-weight: bold;
    color: var(--accent-color);
}

/* Make key input container conditional */
#trithemius-key-container {
    display: none;
}

#trithemius-key-container.show {
    display: block;
} 

/* Cipher Disk Styles - Updated */
.cipher-disk-container {
    margin-top: 2rem;
    text-align: center;
}

.disk-settings {
    background-color: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
}

.disk-settings h4 {
    margin-top: 0;
    color: var(--primary-color);
    border-bottom: 1px solid var(--card-border);
    padding-bottom: 0.5rem;
    margin-bottom: 1rem;
}

.disk-control-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.disk-control-buttons button {
    background-color: var(--secondary-color);
    color: white;
    border: none;
    padding: 8px 12px;
    border-radius: 4px;
    cursor: pointer;
    flex: 1;
    min-width: 120px;
    transition: all 0.3s ease;
}

.disk-control-buttons button:hover {
    background-color: var(--primary-color);
}

/* Rotation mode selector */
.rotation-mode-selector {
    margin-bottom: 0.75rem;
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}
.rotation-mode-selector.rotation-mode-below{
    justify-content: center;
    margin-top: -0.25rem;
}
.rotation-mode-selector label {
    font-size: 0.85rem;
}

.result-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.5rem;
}

.result-actions {
    display: flex;
    gap: 0.5rem;
}

.icon-button {
    background: transparent;
    border: 1px solid var(--card-border);
    border-radius: 50%;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.3s ease;
}

.icon-button:hover {
    background-color: var(--highlight-bg);
    color: var(--accent-color);
}

.cipher-disk-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    margin-top: 1rem;
}

.cipher-disk {
    position: relative;
    width: 300px;
    height: 300px;
    margin: 0 auto;
}

.outer-disk, .inner-disk {
    position: absolute;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    box-shadow: none;
}

.outer-disk {
    width: 300px;
    height: 300px;
    background-color: #fff; /* white disk like screenshot */
    border: 2px solid var(--primary-color);
    z-index: 1;
    transition: transform 0.3s ease;
}
.outer-disk::before,
.outer-disk::after{
    content: '';
    position: absolute;
    inset: 10px; /* inner ring gap */
    border: 2px solid var(--primary-color);
    border-radius: 50%;
}
.outer-disk::after{
    inset: 50px; /* inner solid circle boundary like image */
}

.inner-disk {
    width: 220px;
    height: 220px;
    background-color: transparent;
    border: none;
    top: 40px;
    left: 40px;
    z-index: 2;
    transition: transform 0.3s ease;
}
.inner-disk::before{
    content:'';
    position:absolute;
    inset: 0;
    border-radius:50%;
    border:2px solid var(--primary-color);
}

.disk-center {
    position: absolute;
    width: 10px;
    height: 10px;
    background: radial-gradient(circle at center, rgba(0,0,0,0.9) 0 45%, rgba(0,0,0,0.4) 60%, transparent 70%);
    border-radius: 50%;
    top: calc(150px - 5px);
    left: calc(150px - 5px);
    z-index: 4;
}

.alignment-marker {
    position: absolute;
    width: 2px;
    height: 150px;
    background-color: var(--primary-color);
    top: 0;
    left: 149px;
    z-index: 3;
}

.disk-letter {
    position: absolute;
    font-size: 0.9rem;
    font-weight: 600;
    width: 22px;
    height: 22px;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 0;
    background-color: transparent; /* no boxes, just letters */
    border: none;
    color: #111; /* dark text on white disk */
}

.inner-letter {
    background-color: transparent;
    color: #111;
    z-index: 3;
}

/* highlight index/key letters in orange like screenshot */
.disk-letter.highlight,
.disk-letter.index-letter,
.disk-letter.key-letter,
.disk-letter.is-accent{ color: var(--accent-color); }

/* radial dividers for disk rings */
.ring-divider{
    position:absolute;
    width:1px;                 /* mảnh hơn */
    height:40px;               /* chỉ vạch tick gần vành, không kéo tới tâm */
    left:149px;
    top:110px;                 /* đáy nằm ở tâm (150px) => 110 + 40 = 150 */
    background-color: var(--primary-color);
    opacity: 0.25;             /* rất nhẹ, không gây "xám xám" */
    z-index:1;
    transform-origin: bottom center;
    pointer-events: none;
}
.inner-divider{
    display: none; /* tắt tia ở vòng trong để không bị rối */
}

.disk-controls {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1rem;
}

.disk-control-btn {
    background-color: var(--primary-color);
    color: var(--light-color);
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: all 0.3s ease;
}

.disk-control-btn:hover {
    background-color: var(--secondary-color);
    transform: scale(1.1);
}

.disk-control-btn:active {
    transform: scale(0.95);
}

.cipher-disk-container h4, .cipher-disk-container h5 {
    margin-bottom: 0.5rem;
}

.algorithm-formula {
    background-color: var(--highlight-bg);
    border-radius: 8px;
    padding: 1rem;
    margin-top: 2rem;
    text-align: left;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.algorithm-formula h5 {
    margin-top: 0;
    color: var(--primary-color);
    font-weight: bold;
}

.algorithm-formula ol {
    margin: 0;
    padding-left: 1.5rem;
    color: var(--text-color);
}

.algorithm-formula li {
    margin-bottom: 0.5rem;
}

.disk-titles {
    margin-bottom: 1rem;
}

/* Responsive adjustments for Cipher Disk */
@media (max-width: 600px) {
    .cipher-disk {
        width: 250px;
        height: 250px;
    }
    
    .outer-disk {
        width: 250px;
        height: 250px;
    }
    
    .inner-disk {
        width: 180px;
        height: 180px;
        top: 35px;
        left: 35px;
    }
    
    .disk-center {
        top: 110px;
        left: 110px;
    }
    
    .alignment-marker {
        left: 124px;
    }
    
    .disk-letter {
        width: 22px;
        height: 22px;
        font-size: 0.9rem;
    }
    
    .algorithm-formula {
        padding: 0.75rem;
    }
}

@media (max-width: 400px) {
    .cipher-disk {
        width: 200px;
        height: 200px;
    }
    
    .outer-disk {
        width: 200px;
        height: 200px;
    }
    
    .inner-disk {
        width: 140px;
        height: 140px;
        top: 30px;
        left: 30px;
    }
    
    .disk-center {
        width: 25px;
        height: 25px;
        top: 87.5px;
        left: 87.5px;
    }
    
    .alignment-marker {
        height: 30px;
        left: 99px;
    }
    
    .disk-letter {
        width: 18px;
        height: 18px;
        font-size: 0.8rem;
    }
} 

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.5);
}

.modal-content {
    position: relative;
    background-color: var(--card-bg);
    margin: 5% auto; /* reduce top/bottom, keep centered */
    padding: 0; /* ensure header/body/footer handle padding */
    width: 90%;
    max-width: 700px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    animation: modalFadeIn 0.3s ease;
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--card-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h4 {
    margin: 0;
    color: var(--primary-color);
    font-size: 1.2rem;
}

.close-modal {
    color: var(--text-color);
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: var(--accent-color);
}

.modal-body {
    padding: 1.5rem;
    max-height: 60vh;
    overflow-y: auto;
}

.modal-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--card-border);
    display: flex;
    justify-content: flex-end;
}

.modal-footer button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.modal-footer button:hover {
    background-color: var(--secondary-color);
}

.explanation-button-container {
    display: flex;
    justify-content: center;
    margin-top: 1rem;
}

.btn-explanation {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
}

.btn-explanation:hover {
    background-color: var(--primary-color);
    transform: translateY(-2px);
}

.btn-explanation:active {
    transform: translateY(0);
}

.btn-explanation::before {
    content: "\f05a";
    font-family: 'Font Awesome 5 Free';
    font-weight: 900;
}

/* Style for explanation content in modal */
.modal .explanation-content {
    color: var(--text-color);
}

.modal .step {
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--card-border);
}

.modal .step:last-child {
    border-bottom: none;
} 

/* Style for explanation table in modal */
.explanation-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    font-size: 0.9rem;
}

.explanation-table th,
.explanation-table td {
    border: 1px solid var(--card-border);
    padding: 0.5rem;
    text-align: left;
}

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

.explanation-table tr:nth-child(even) {
    background-color: var(--highlight-bg);
}

.explanation-table code {
    background-color: var(--card-bg);
    padding: 0.1rem 0.3rem;
    border-radius: 3px;
    font-family: monospace;
    border: 1px solid var(--card-border);
}

.formula ul {
    margin: 0.5rem 0;
    padding-left: 1.5rem;
}

.formula li {
    margin-bottom: 0.3rem;
} 

.icon-btn {
    cursor: pointer;
    margin-left: 0.5rem;
    color: var(--accent-color);
    transition: color 0.3s ease;
    font-size: 0.9rem;
}

.icon-btn:hover {
    color: var(--primary-color);
} 

/* Make Trithemius Tabula Recta & Vigenère Square smaller */
#trithemius-table {
    grid-template-columns: repeat(27, 24px);
}

#vigenere-square {
    grid-template-columns: repeat(27, 24px);
}

#trithemius-table .cell,
#vigenere-square .cell {
    width: 24px;
    height: 24px;
}

@media (max-width: 600px) {
    #trithemius-table {
        grid-template-columns: repeat(27, 18px);
    }
    #vigenere-square {
        grid-template-columns: repeat(27, 18px);
    }
    #trithemius-table .cell,
    #vigenere-square .cell {
        width: 18px;
        height: 18px;
        font-size: 0.7rem;
    }
}