:root {
    /* Colors */
    --color-tone-1: #1a1a1b;
    --color-tone-2: #787c7e;
    --color-tone-3: #818384;
    --color-tone-4: #3a3a3c;
    --color-tone-5: #272729;
    --color-tone-6: #1a1a1b;
    --color-tone-7: #d7dadc;
    --color-nav-border: #3a3a3c;
    
    /* Game colors */
    --color-correct: #2563eb;
    --color-present: #fb923c;
    --color-absent: #787c7e;
    --color-evaluated-background: #1a1a1b;
    
    /* Text colors */
    --color-text-primary: #ffffff;
    --color-text-secondary: #818384;
    
    /* Background colors */
    --color-background: #121213;
    --color-background-secondary: #1a1a1b;
    
    /* Border colors */
    --color-border-primary: #3a3a3c;
    --color-border-secondary: #272729;
    
    /* Key colors */
    --color-key-background: #818384;
    --color-key-background-active: #565758;
    --color-key-text: #ffffff;
    
    /* Modal colors */
    --color-modal-background: rgba(0, 0, 0, 0.5);
    --color-modal-content: #1a1a1b;
    
    /* Game board */
    --gap-size: 5px;
    --tile-size: 62px;
    --board-height: calc(5 * var(--tile-size) + 4 * var(--gap-size));
    --keyboard-height: 200px;
    
    /* Animation */
    --animation-speed: 250ms;
    --animation-easing: ease-in-out;
}

/* Light theme overrides */
body:not(.dark-theme) {
    --color-tone-1: #000000;
    --color-tone-2: #787c7e;
    --color-tone-3: #878a8c;
    --color-tone-4: #d3d6da;
    --color-tone-5: #edeff1;
    --color-tone-6: #f6f7f8;
    --color-tone-7: #ffffff;
    --color-nav-border: #d3d6da;
    
    --color-text-primary: #000000;
    --color-text-secondary: #787c7e;
    
    --color-background: #ffffff;
    --color-background-secondary: #f6f7f8;
    
    --color-border-primary: #d3d6da;
    --color-border-secondary: #edeff1;
    
    --color-key-background: #d3d6da;
    --color-key-background-active: #787c7e;
    --color-key-text: #000000;
    
    --color-modal-content: #ffffff;
    --color-evaluated-background: #ffffff;
}

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

body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--color-background);
    color: var(--color-text-primary);
    line-height: 1.4;
    overflow-x: hidden;
}

#app {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    max-width: 500px;
    margin: 0 auto;
    position: relative;
}

/* Header */
.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    height: 50px;
    border-bottom: 1px solid var(--color-nav-border);
}

.header-left,
.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Game Mode Selector */
.game-mode-selector {
    display: flex;
    align-items: center;
}

.mode-dropdown {
    background-color: var(--color-background-secondary);
    border: 2px solid var(--color-border-primary);
    border-radius: 6px;
    color: var(--color-text-primary);
    font-size: 14px;
    font-weight: 500;
    padding: 6px 12px;
    cursor: pointer;
    transition: border-color 0.2s ease, background-color 0.2s ease;
    min-width: 100px;
}

.mode-dropdown:hover {
    border-color: var(--color-correct);
    background-color: var(--color-background);
}

.mode-dropdown:focus {
    outline: none;
    border-color: var(--color-correct);
    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
}

.mode-dropdown option {
    background-color: var(--color-background-secondary);
    color: var(--color-text-primary);
    padding: 8px;
}

.title-container {
    display: flex;
    align-items: center;
    gap: 12px;
    justify-content: center;
    flex: 1;
}

.title {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: 0.1rem;
    text-align: center;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Time Trial Info */
.time-trial-info {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    margin-left: 16px;
}

.timer-display {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-present);
    background-color: var(--color-background-secondary);
    padding: 4px 12px;
    border-radius: 12px;
    border: 1px solid var(--color-present);
}

.word-progress {
    font-size: 12px;
    color: var(--color-text-secondary);
    font-weight: 500;
}

.icon-btn {
    background: none;
    border: none;
    color: var(--color-text-primary);
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.1s ease;
}

.icon-btn:hover {
    background-color: var(--color-tone-4);
}

.icon-btn:focus {
    outline: 2px solid var(--color-correct);
    outline-offset: 2px;
}

/* Main game container */
.game-container {
    display: flex;
    flex-direction: column;
    flex: 1;
    padding: 0 16px;
    max-height: calc(100vh - 50px);
    overflow: hidden;
}

/* Game board */
.game-board {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px 0;
    margin: 0 auto;
    width: 100%;
    max-width: 600px;
    gap: 20px;
}

/* Tiles container */
.tiles-container {
    display: flex;
    flex-direction: column;
    gap: var(--gap-size);
}

.game-row {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: var(--gap-size);
}

/* 6-letter word mode */
.tiles-container[data-word-length="6"] .game-row {
    grid-template-columns: repeat(6, 1fr);
}

.tiles-container[data-word-length="6"] .tile {
    width: 52px;
    height: 52px;
    font-size: 28px;
}

.tile {
    width: var(--tile-size);
    height: var(--tile-size);
    border: 2px solid var(--color-tone-4);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    font-weight: bold;
    text-transform: uppercase;
    user-select: none;
    background-color: var(--color-evaluated-background);
    color: var(--color-text-primary);
    transition: all var(--animation-speed) var(--animation-easing);
}

.tile-filled {
    border-color: var(--color-tone-3);
    animation: tile-pop 0.1s ease-in-out;
}

.tile-correct {
    background-color: var(--color-correct);
    border-color: var(--color-correct);
    color: white;
}

.tile-present {
    background-color: var(--color-present);
    border-color: var(--color-present);
    color: white;
}

.tile-absent {
    background-color: var(--color-absent);
    border-color: var(--color-absent);
    color: white;
}

/* Definitions container */
.definitions-container {
    width: 100%;
    min-height: 120px;
    max-height: 200px;
    background-color: var(--color-background-secondary);
    border: 2px solid var(--color-border-primary);
    border-radius: 8px;
    padding: 16px;
    overflow-y: auto;
    margin-top: 10px;
}

.definitions-title {
    margin: 0 0 16px 0;
    color: var(--color-text-primary);
    font-size: 18px;
    font-weight: bold;
    text-align: center;
    border-bottom: 1px solid var(--color-border-primary);
    padding-bottom: 8px;
}

/* Individual definition items */
.definition-item {
    margin-bottom: 12px;
    padding: 10px 14px;
    background-color: var(--color-background);
    border: 1px solid var(--color-border-secondary);
    border-radius: 6px;
    border-left: 4px solid var(--color-correct);
    transition: all 0.3s ease;
}

.definition-item:last-child {
    margin-bottom: 0;
}

/* Highlight for newly added definitions */
.definition-item.newly-added {
    background-color: var(--color-present);
    border-color: var(--color-present);
    border-left-color: var(--color-present);
    color: white;
    transform: scale(1.02);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.definition-item.newly-added .word-text,
.definition-item.newly-added .part-of-speech,
.definition-item.newly-added .definition-text {
    color: white;
}

.definition-content {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 8px;
}

.word-text {
    font-weight: bold;
    color: var(--color-text-primary);
    font-size: 16px;
}

.part-of-speech {
    font-style: italic;
    color: var(--color-text-secondary);
    font-size: 12px;
}

.definition-text {
    color: var(--color-text-primary);
    font-size: 14px;
    line-height: 1.4;
    flex: 1;
    min-width: 200px;
}

/* Responsive design for smaller screens */
@media (max-width: 768px) {
    .definitions-container {
        max-height: 150px;
        min-height: 100px;
    }
    
    .definition-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }
    
    .definition-text {
        min-width: auto;
    }
}

/* Keyboard */
.keyboard {
    margin-top: auto;
    padding-bottom: 20px;
}

.keyboard-row {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin-bottom: 8px;
}

.keyboard-row:nth-child(2) {
    margin: 0 15px 8px;
}

.key {
    min-width: 43px;
    height: 58px;
    border-radius: 4px;
    border: none;
    background-color: var(--color-key-background);
    color: var(--color-key-text);
    font-weight: bold;
    font-size: 14px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    text-transform: uppercase;
    transition: all 0.1s ease;
    user-select: none;
}

.key:hover {
    background-color: var(--color-key-background-active);
}

.key:focus {
    outline: 2px solid var(--color-correct);
    outline-offset: 2px;
}

.key-large {
    min-width: 65px;
    font-size: 12px;
}

.key-correct {
    background-color: var(--color-correct) !important;
    color: white !important;
}

.key-present {
    background-color: var(--color-present) !important;
    color: white !important;
}

.key-absent {
    background-color: var(--color-absent) !important;
    color: white !important;
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--color-modal-background);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal.modal-open {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background-color: var(--color-modal-content);
    border-radius: 8px;
    max-width: 90vw;
    max-height: 90vh;
    width: 500px;
    overflow-y: auto;
    position: relative;
    box-shadow: 0 4px 23px 0 rgba(0, 0, 0, 0.2);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--color-border-primary);
}

.modal-header h2 {
    font-size: 20px;
    font-weight: 700;
}

.close-btn {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--color-text-primary);
    padding: 4px;
    line-height: 1;
}

.close-btn:hover {
    background-color: var(--color-tone-4);
    border-radius: 4px;
}

.modal-body {
    padding: 20px;
}

.modal-actions {
    display: flex;
    flex-direction: column;
    gap: 16px;
    align-items: center;
    margin-top: 20px;
}

/* Multiple buttons in modal actions */
.modal-actions:has(#level2-modal-btn) {
    flex-direction: row;
    justify-content: center;
    flex-wrap: wrap;
}

@media (max-width: 480px) {
    .modal-actions:has(#level2-modal-btn) {
        flex-direction: column;
    }
}

/* Buttons */
.btn {
    background-color: var(--color-correct);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 6px;
    font-weight: bold;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: background-color 0.1s ease;
}

.btn:hover {
    background-color: #5a9454;
}

.btn:focus {
    outline: 2px solid var(--color-text-primary);
    outline-offset: 2px;
}

.btn.level2-btn {
    background-color: var(--color-present);
}

.btn.level2-btn:hover {
    background-color: #b8a351;
}

/* Statistics */
.stats-container {
    display: flex;
    justify-content: space-around;
    margin: 20px 0;
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 32px;
    font-weight: bold;
}

.stat-label {
    font-size: 12px;
    color: var(--color-text-secondary);
    text-transform: uppercase;
}

/* Guess distribution */
.guess-distribution {
    margin: 20px 0;
}

.guess-distribution h3 {
    margin-bottom: 16px;
    font-size: 16px;
}

.distribution-container {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.guess-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.guess-number {
    font-weight: bold;
    width: 12px;
    text-align: center;
}

.guess-bar {
    background-color: var(--color-absent);
    height: 20px;
    min-width: 20px;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    padding: 0 8px;
    border-radius: 2px;
    width: var(--bar-width, 7%);
    max-width: 100%;
    transition: width 0.3s ease;
}

.guess-bar.current-guess {
    background-color: var(--color-correct);
}

.guess-count {
    color: white;
    font-weight: bold;
    font-size: 14px;
}

/* Settings */
.setting-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border-primary);
}

.setting-row:last-child {
    border-bottom: none;
}

.setting-info {
    flex: 1;
}

.setting-title {
    font-weight: bold;
    margin-bottom: 4px;
}

.setting-description {
    font-size: 14px;
    color: var(--color-text-secondary);
}

/* Toggle switch */
.toggle {
    opacity: 0;
    position: absolute;
}

.toggle-label {
    display: block;
    width: 50px;
    height: 26px;
    background-color: var(--color-tone-4);
    border-radius: 13px;
    position: relative;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.toggle-label::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 22px;
    height: 22px;
    background-color: white;
    border-radius: 50%;
    transition: transform 0.2s ease;
}

.toggle:checked + .toggle-label {
    background-color: var(--color-correct);
}

.toggle:checked + .toggle-label::after {
    transform: translateX(24px);
}

/* Toast notifications */
.toast-container {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2000;
    pointer-events: none;
}

.toast {
    background-color: var(--color-tone-4);
    color: var(--color-text-primary);
    padding: 12px 16px;
    border-radius: 6px;
    margin-bottom: 8px;
    font-weight: bold;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    transform: translateY(-100px);
    opacity: 0;
    transition: all 0.3s ease;
}

.toast.toast-show {
    transform: translateY(0);
    opacity: 1;
}

/* Help content */
.modal-body p {
    margin-bottom: 16px;
}

.modal-body ul {
    margin: 16px 0;
    padding-left: 20px;
}

.modal-body li {
    margin-bottom: 8px;
}

.examples {
    margin: 20px 0;
}

.examples h3 {
    margin-bottom: 16px;
}

.example-word {
    display: flex;
    gap: 4px;
    margin: 16px 0;
}

.example-word .tile {
    width: 40px;
    height: 40px;
    font-size: 20px;
}

/* Accessibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* Focus indicators */
*:focus {
    outline: 2px solid var(--color-correct);
    outline-offset: 2px;
}

/* Responsive design */
@media (max-width: 480px) {
    :root {
        --tile-size: 52px;
        --gap-size: 4px;
    }
    
    .title {
        font-size: 22px;
        letter-spacing: 0.05rem;
    }
    
    .title-container {
        gap: 8px;
    }
    
    .tile {
        font-size: 28px;
    }
    
    .key {
        min-width: 35px;
        height: 50px;
        font-size: 12px;
    }
    
    .key-large {
        min-width: 55px;
        font-size: 10px;
    }
    
    .game-container {
        padding: 0 8px;
    }
    
    .modal-content {
        margin: 20px;
        width: calc(100% - 40px);
    }
}

@media (max-width: 360px) {
    .title {
        font-size: 20px;
        letter-spacing: 0.02rem;
    }
    
    .title-container {
        gap: 6px;
    }
}

@media (max-width: 320px) {
    :root {
        --tile-size: 48px;
    }
    
    .title {
        font-size: 18px;
        letter-spacing: 0;
    }
    
    .key {
        min-width: 32px;
        height: 46px;
    }
    
    .key-large {
        min-width: 50px;
    }
}