:root {
    /* Light theme variables */
    --light-bg: #f5f7fa;
    --light-card: #ffffff;
    --light-text: #161f2c;
    --light-text-secondary: #475569;
    --light-border: #e2e8f0;
    --light-hover: #f1f5f9;
    --light-accent: #ff5e00;
    --light-accent-light: #ffa477;
    --light-key-bg: #f1f5f9;
    --light-key-border: #cbd5e1;
    --light-key-text: #1e293b;
    
    /* Dark theme variables */
    --dark-bg: #141b26;
    --dark-card: #1c2434;
    --dark-text: #e2e8f0;
    --dark-text-secondary: #94a3b8;
    --dark-border: #2c3c52;
    --dark-hover: #263244;
    --dark-accent: #ff7a2e;
    --dark-accent-light: #ff9a5b;
    --dark-key-bg: #2c3c52;
    --dark-key-border: #3b4f6c;
    --dark-key-text: #e2e8f0;
    
    /* New 3D key variables */
    --light-key-top: #ffffff;
    --light-key-side: #e2e8f0;
    --light-key-shadow: rgba(0, 0, 0, 0.1);
    --dark-key-top: #2c3c52;
    --dark-key-side: #1c2738;
    --dark-key-shadow: rgba(0, 0, 0, 0.3);
    
    /* Key highlight colors */
    --key-orange: #ff7a2e;
    --key-blue: #3b82f6;
    --key-green: #10b981;
    --key-purple: #8b5cf6;
    --key-red: #ef4444;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.5;
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Theme classes */
body.light {
    background-color: var(--light-bg);
    color: var(--light-text);
}

body.dark {
    background-color: var(--dark-bg);
    color: var(--dark-text);
}

/* Header */
header {
    padding: 1rem 1.25rem 0.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.75rem;
    position: sticky;
    top: 0;
    z-index: 10;
    backdrop-filter: blur(10px);
}

.light header {
    background-color: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid var(--light-border);
}

.dark header {
    background-color: rgba(20, 27, 38, 0.8);
    border-bottom: 1px solid var(--dark-border);
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo {
    height: 2.25rem;
    width: auto;
}

h1 {
    font-size: 1.4rem;
    font-weight: 700;
}

.light h1 {
    color: var(--light-text);
}

.dark h1 {
    color: var(--dark-text);
}

.controls {
    display: flex;
    gap: 0.75rem;
    align-items: center;
    flex-wrap: wrap;
}

.search-container {
    position: relative;
    width: 280px;
}

.search-icon {
    position: absolute;
    top: 50%;
    left: 0.75rem;
    transform: translateY(-50%);
    color: var(--light-text-secondary);
    pointer-events: none;
}

.dark .search-icon {
    color: var(--dark-text-secondary);
}

#search {
    width: 100%;
    padding: 0.6rem 0.75rem 0.6rem 2.25rem;
    border-radius: 1.5rem;
    border: none;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.light #search {
    background-color: var(--light-card);
    color: var(--light-text);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.dark #search {
    background-color: var(--dark-card);
    color: var(--dark-text);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

#search:focus {
    outline: none;
}

.light #search:focus {
    box-shadow: 0 0 0 2px var(--light-accent-light);
}

.dark #search:focus {
    box-shadow: 0 0 0 2px var(--dark-accent-light);
}

#theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    width: 2.25rem;
    height: 2.25rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.light #theme-toggle {
    color: var(--light-text);
}

.dark #theme-toggle {
    color: var(--dark-text);
}

#theme-toggle:hover {
    background-color: var(--light-hover);
}

.dark #theme-toggle:hover {
    background-color: var(--dark-hover);
}

/* Main content - more compact */
main {
    flex: 1;
    padding: 0.5rem 1rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

.category {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.category h2 {
    font-size: 1.1rem;
    font-weight: 600;
    padding-bottom: 0.2rem;
    border-bottom: 2px solid;
    width: fit-content;
    margin-bottom: 0.2rem;
}

.light .category h2 {
    border-color: var(--light-accent);
    color: var(--light-accent);
}

.dark .category h2 {
    border-color: var(--dark-accent);
    color: var(--dark-accent);
}

.shortcuts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 0.6rem;
}

.shortcut {
    padding: 0.65rem;
    border-radius: 0.6rem;
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    animation: fadeIn 0.3s ease-out;
    position: relative;
    overflow: hidden;
    background-image: linear-gradient(to bottom, rgba(255,255,255,0.05), rgba(0,0,0,0.05));
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.shortcut:hover {
    transform: translateY(-3px) scale(1.02);
}

.light .shortcut {
    background-color: var(--light-card);
    box-shadow: 
        0 4px 12px rgba(0, 0, 0, 0.05),
        0 12px 25px rgba(0, 0, 0, 0.03);
}

.dark .shortcut {
    background-color: var(--dark-card);
    box-shadow: 
        0 4px 12px rgba(0, 0, 0, 0.2),
        0 12px 25px rgba(0, 0, 0, 0.15);
}

.light .shortcut:hover {
    box-shadow: 
        0 6px 18px rgba(0, 0, 0, 0.08),
        0 15px 35px rgba(0, 0, 0, 0.05);
}

.dark .shortcut:hover {
    box-shadow: 
        0 6px 18px rgba(0, 0, 0, 0.25),
        0 15px 35px rgba(0, 0, 0, 0.18);
}

.action {
    font-size: 0.95rem;
    line-height: 1.2;
    padding-bottom: 0.35rem;
    margin-bottom: 0.2rem;
    font-weight: 700;
    text-align: center;
    color: var(--light-accent);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
    position: relative;
}

.action::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 30%;
    right: 30%;
    height: 1px;
    background-color: var(--light-accent);
    opacity: 0.3;
    border-radius: 1px;
}

.dark .action {
    color: var(--dark-accent);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

.dark .action::after {
    background-color: var(--dark-accent);
}

.keys {
    gap: 0.2rem;
    min-height: 2.4rem;
    padding: 0.15rem;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    border-radius: 0.4rem;
}

.light .keys {
    background-color: rgba(0, 0, 0, 0.01);
}

.dark .keys {
    background-color: rgba(255, 255, 255, 0.01);
}

/* 3D Keyboard Key Styling - more compact */
.key {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 2rem;
    height: 2rem;
    padding: 0.15rem 0.35rem;
    font-family: 'SF Mono', 'Consolas', 'Liberation Mono', Menlo, monospace;
    font-weight: 600;
    font-size: 0.8rem;
    border-radius: 0.3rem;
    transform-style: preserve-3d;
    transform: perspective(500px) rotateX(6deg);
    transition: all 0.15s;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    background-image: linear-gradient(to bottom, rgba(255,255,255,0.1), rgba(0,0,0,0.05));
}

.shortcut:hover .key {
    transform: perspective(500px) rotateX(10deg) translateY(-1px);
}

.light .key {
    background-color: var(--light-key-top);
    color: var(--light-key-text);
    box-shadow: 
        0 1px 1px var(--light-key-shadow),
        0 2px 0 var(--light-key-side),
        0 2px 2px var(--light-key-shadow);
    border: 1px solid rgba(0,0,0,0.05);
}

.dark .key {
    background-color: var(--dark-key-top);
    color: var(--dark-key-text);
    box-shadow: 
        0 1px 1px var(--dark-key-shadow),
        0 2px 0 var(--dark-key-side),
        0 2px 2px var(--dark-key-shadow);
    border: 1px solid rgba(255,255,255,0.05);
}

.key:active, .shortcut:active .key {
    transform: perspective(500px) rotateX(6deg) translateY(1px);
}

.light .key:active, .light .shortcut:active .key {
    box-shadow: 
        0 1px 1px var(--light-key-shadow),
        0 1px 0 var(--light-key-side),
        0 1px 1px var(--light-key-shadow);
}

.dark .key:active, .dark .shortcut:active .key {
    box-shadow: 
        0 1px 1px var(--dark-key-shadow),
        0 1px 0 var(--dark-key-side),
        0 1px 1px var(--dark-key-shadow);
}

/* Key type styling */
.key.modifier {
    background-color: var(--key-blue);
    color: white;
}

.dark .key.modifier {
    background-color: var(--key-blue);
    box-shadow: 
        0 1px 1px var(--dark-key-shadow),
        0 3px 0 rgba(37, 99, 235, 0.8),
        0 3px 3px var(--dark-key-shadow);
}

.light .key.modifier {
    box-shadow: 
        0 1px 1px var(--light-key-shadow),
        0 3px 0 rgba(37, 99, 235, 0.8),
        0 3px 3px var(--light-key-shadow);
}

/* Special key styling for numpad, function keys, etc. */
.key:not(.modifier):not(.mouse) {
    background-color: var(--dark-accent);
    color: white;
}

.light .key:not(.modifier):not(.mouse) {
    box-shadow: 
        0 1px 1px var(--light-key-shadow),
        0 3px 0 rgba(217, 70, 0, 0.8),
        0 3px 3px var(--light-key-shadow);
}

.dark .key:not(.modifier):not(.mouse) {
    box-shadow: 
        0 1px 1px var(--dark-key-shadow),
        0 3px 0 rgba(217, 70, 0, 0.8),
        0 3px 3px var(--dark-key-shadow);
}

/* Key operators */
.operator {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 0.25rem;
    font-weight: 600;
    opacity: 0.8;
    font-size: 0.9rem;
}

/* Text operators like 'drag' and 'hold' */
.text-operator {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 0.1rem;
    font-weight: 500;
    opacity: 0.7;
    font-style: italic;
    font-size: 0.75rem;
}

/* Mouse keys - more compact */
.key.mouse {
    position: relative;
    border-radius: 1.2rem;
    font-size: 0.6rem;
    height: 2rem;
    min-width: 1.5rem;
    overflow: hidden;
    text-transform: none;
    letter-spacing: 0;
    background-image: linear-gradient(to bottom, rgba(255,255,255,0.15), rgba(0,0,0,0.1));
}

.light .key.mouse {
    background-color: #e0e5ec;
}

.dark .key.mouse {
    background-color: #2d3748;
}

.key.mouse::before {
    content: "🖱️";
    display: block;
    font-size: 0.9rem;
    margin-bottom: 0.05rem;
}

.key.mouse.lmb::after,
.key.mouse.mmb::after,
.key.mouse.rmb::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    height: 0.7rem;
    border-radius: 0.35rem;
}

.key.mouse.lmb::after {
    top: 0.35rem;
    background-color: transparent;
}

.key.mouse.mmb::after {
    top: 0.9rem;
    background-color: transparent;
}

.key.mouse.rmb::after {
    top: 0.35rem;
    right: 0;
    left: 50%;
    background-color: transparent;
}

/* Key sizes */
.key.small {
    min-width: 1.6rem;
    height: 1.6rem;
    font-size: 0.9rem;
}

.key.medium {
    min-width: 2rem;
    height: 1.8rem;
    font-size: 0.75rem;
}

.key.large {
    min-width: 3.2rem;
    height: 1.8rem;
    font-size: 0.75rem;
}

.key.space {
    min-width: 4rem;
    height: 1.8rem;
}

/* Styling for key components */
.plus, .or, .then, .paren {
    opacity: 0.6;
}

.modifier, .mouse {
    font-weight: 600;
    padding: 0.1rem 0.25rem;
    border-radius: 0.2rem;
    display: inline-block;
    margin: 0 0.1rem;
}

.mouse {
    display: inline-flex;
    align-items: center;
    gap: 0.15rem;
}

.light .modifier, .light .mouse {
    background-color: var(--light-key-bg);
    border: 1px solid var(--light-key-border);
    color: var(--light-key-text);
}

.dark .modifier, .dark .mouse {
    background-color: var(--dark-key-bg);
    border: 1px solid var(--dark-key-border);
    color: var(--dark-key-text);
}

.action-desc {
    font-style: italic;
    opacity: 0.8;
}

/* Footer */
footer {
    padding: 1rem;
    text-align: center;
    font-size: 0.85rem;
}

.light footer {
    background-color: var(--light-card);
    border-top: 1px solid var(--light-border);
    color: var(--light-text-secondary);
}

.dark footer {
    background-color: var(--dark-card);
    border-top: 1px solid var(--dark-border);
    color: var(--dark-text-secondary);
}

footer a {
    text-decoration: none;
    font-weight: 500;
}

.light footer a {
    color: var(--light-accent);
}

.dark footer a {
    color: var(--dark-accent);
}

footer a:hover {
    text-decoration: underline;
}

.help-text {
    margin-top: 0.4rem;
}

.citation {
    margin-top: 0.5rem;
    font-size: 0.8rem;
    opacity: 0.8;
}

kbd {
    font-family: 'SF Mono', 'Consolas', 'Liberation Mono', Menlo, monospace;
    padding: 0.1rem 0.2rem;
    border-radius: 0.2rem;
    font-size: 0.75rem;
}

.light kbd {
    background-color: var(--light-key-bg);
    border: 1px solid var(--light-key-border);
    color: var(--light-key-text);
}

.dark kbd {
    background-color: var(--dark-key-bg);
    border: 1px solid var(--dark-key-border);
    color: var(--dark-key-text);
}

/* Media queries for responsive layout */
@media (min-width: 640px) {
    .shortcuts-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    }
}

@media (min-width: 1024px) {
    .shortcuts-grid {
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    }
}

@media (min-width: 1280px) {
    .shortcuts-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
    
    main {
        max-width: 1500px;
    }
}

/* Adjust responsive styles for better mobile experience */
@media (max-width: 768px) {
    header {
        padding: 0.75rem 0.75rem 0.4rem;
        justify-content: center;
    }
    
    .controls {
        width: 100%;
        justify-content: center;
    }
    
    .search-container {
        width: 100%;
    }
    
    .categories-container {
        padding: 0.4rem 0.75rem 0.5rem;
        top: 6.5rem;
        justify-content: center;
    }
    
    .category h2 {
        margin-top: 1.25rem;
    }
    
    /* Adjust grid for tablet */
    .shortcuts-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    }
}

@media (max-width: 480px) {
    .controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .categories-container {
        padding: 0.4rem 0.6rem 0.5rem;
        top: 8.5rem;
    }
    
    .category-pill {
        font-size: 0.75rem;
        padding: 0.3rem 0.6rem;
    }
    
    #theme-toggle {
        align-self: flex-end;
        margin-top: -2.25rem;
    }
    
    /* Adjust grid for mobile */
    .shortcuts-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    }
}

/* Categories container - more compact */
.categories-container {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    padding: 0.4rem 1rem 0.6rem;
    overflow-x: auto;
    position: sticky;
    top: 3.5rem;
    z-index: 9;
    backdrop-filter: blur(10px);
}

.light .categories-container {
    background-color: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid var(--light-border);
}

.dark .categories-container {
    background-color: rgba(20, 27, 38, 0.8);
    border-bottom: 1px solid var(--dark-border);
}

.category-pill {
    padding: 0.35rem 0.7rem;
    border-radius: 1.25rem;
    font-size: 0.75rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    white-space: nowrap;
}

.light .category-pill {
    background-color: var(--light-card);
    color: var(--light-text);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.dark .category-pill {
    background-color: var(--dark-card);
    color: var(--dark-text);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

.category-pill:hover {
    transform: translateY(-1px);
}

.light .category-pill:hover {
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.dark .category-pill:hover {
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.4);
}

.category-pill.active {
    background-color: var(--dark-accent);
    color: white;
}

.light .category-pill.active {
    background-color: var(--light-accent);
}

.category-pill.disabled {
    opacity: 0.5;
}

.category-pill.exclusive {
    background-color: var(--dark-accent-light);
    color: white;
    font-weight: 600;
    box-shadow: 0 0 0 1px var(--dark-accent);
    transform: scale(1.03);
}

.light .category-pill.exclusive {
    background-color: var(--light-accent-light);
    box-shadow: 0 0 0 1px var(--light-accent);
}

/* Numpad key styling */
.key.numpad {
    background-color: var(--key-purple);
    color: white;
}

.light .key.numpad {
    box-shadow: 
        0 1px 1px var(--light-key-shadow),
        0 3px 0 rgba(110, 65, 226, 0.8),
        0 3px 3px var(--light-key-shadow);
}

.dark .key.numpad {
    box-shadow: 
        0 1px 1px var(--dark-key-shadow),
        0 3px 0 rgba(110, 65, 226, 0.8),
        0 3px 3px var(--dark-key-shadow);
}

/* Modal for key details */
.keys-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 100;
    padding: 0.75rem;
    backdrop-filter: blur(4px);
}

/* Modal content styling */
.modal-content {
    border-radius: 0.75rem;
    padding: 1.75rem;
    max-width: 550px;
    width: 100%;
    position: relative;
    animation: zoomIn 0.3s ease-out;
    display: flex;
    flex-direction: column;
    align-items: center;
}

@keyframes zoomIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

.light .modal-content {
    background-color: var(--light-card);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
}

.dark .modal-content {
    background-color: var(--dark-card);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
}

#key-detail {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    align-items: center;
    text-align: center;
    width: 100%;
}

#key-detail h3 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--light-accent);
    border-bottom: 2px solid;
    padding-bottom: 0.4rem;
}

.dark #key-detail h3 {
    color: var(--dark-accent);
}

.key-combo {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
    align-items: center;
}

.key-combo .key {
    min-width: 3rem;
    height: 3rem;
    font-size: 1.1rem;
}

.key-combo .operator {
    font-size: 1.3rem;
}

.key-instructions {
    margin-top: 1rem;
    font-size: 0.85rem;
    opacity: 0.7;
    max-width: 85%;
    text-align: center;
}

.close-button {
    position: absolute;
    top: 0.75rem;
    right: 0.75rem;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--dark-text);
    width: 2rem;
    height: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.close-button:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.light .close-button {
    color: var(--light-text);
}

.light .close-button:hover {
    background-color: rgba(0, 0, 0, 0.1);
}