:root {
    --color-bg-primary: #0f4c3a;
    --color-bg-secondary: #1a5c4a;
    --color-accent: #ffd700;
    --color-white: white;
    --color-black: black;
    --color-card-border: #333;
    --color-card-back-primary: #1e3c72;
    --color-card-back-secondary: #2a5298;
    --color-hearts-diamonds: #e74c3c;
    --color-spades-clubs: #2c3e50;
    --color-btn-primary-start: #ffd700;
    --color-btn-primary-end: #ffed4e;
    --color-btn-secondary-start: #e74c3c;
    --color-btn-secondary-end: #c0392b;
    --color-win: #2ecc71;
    --color-lose: #e74c3c;
    --color-push: #f39c12;
    
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 0.75rem;
    --space-lg: 1rem;
    --space-xl: 1.25rem;
    --space-2xl: 1.5rem;
    --space-3xl: 1.875rem;
    --space-4xl: 2rem;
    --space-5xl: 2.5rem;
    
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.375rem;
    
    --shadow-sm: 0 0.25rem 0.5rem rgba(0, 0, 0, 0.3);
    --shadow-md: 0 0.375rem 0.75rem rgba(0, 0, 0, 0.3);
    --shadow-accent: 0 0.25rem 0.5rem rgba(255, 215, 0, 0.3);
    --shadow-secondary: 0 0.25rem 0.5rem rgba(231, 76, 60, 0.3);
    
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.3125rem;
    --font-size-3xl: 1.5rem;
    --font-size-4xl: 1.75rem;
    --font-size-5xl: 2rem;
    --font-size-6xl: 2.5rem;
    
    --card-width-mobile: 3.5rem;
    --card-height-mobile: 4.875rem;
    --card-width-tablet: 4rem;
    --card-height-tablet: 5.625rem;
    --card-width-desktop: 5rem;
    --card-height-desktop: 7rem;
    
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

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

body {
    font-family: "Inter", sans-serif;
    background: linear-gradient(135deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);
    min-height: 100vh;
    color: var(--color-white);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: var(--space-lg);
}

.game-container {
    width: 100%;
    max-width: 25rem;
}

header {
    text-align: center;
    margin-bottom: var(--space-2xl);
}

header h1 {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--color-accent);
    text-shadow: 0.125rem 0.125rem var(--space-xs) rgba(0, 0, 0, 0.5);
}

.game-board {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-2xl);
}

.dealer-section,
.player-section {
    width: 100%;
    text-align: center;
}

.player-info {
    margin-bottom: var(--space-md);
}

.player-info h2 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--space-xs);
}

.score {
    font-size: var(--font-size-base);
    color: var(--color-accent);
    font-weight: 600;
}

.hands-container {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
    align-items: center;
}

.hand-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
}

.hand-label {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-white);
    opacity: 0.6;
    transition: all var(--transition-normal);
}

.hand-label.active {
    color: var(--color-accent);
    opacity: 1;
    text-shadow: 0 0 0.5rem var(--color-accent);
}

.cards-area {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--space-sm);
    min-height: 6rem;
    flex-wrap: wrap;
}

.card {
    width: var(--card-width-mobile);
    height: var(--card-height-mobile);
    border-radius: var(--border-radius-sm);
    border: 0.0625rem solid var(--color-card-border);
    background: var(--color-white);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-sm);
    font-weight: 600;
    color: var(--color-black);
    position: relative;
    cursor: pointer;
    transform-style: preserve-3d;
    transition: transform var(--transition-normal);
    box-shadow: var(--shadow-sm);
    font-size: var(--font-size-xs);
}

.card:hover {
    transform: translateY(-0.1875rem) scale(1.05);
}

.card-back {
    background: linear-gradient(45deg, var(--color-card-back-primary) 0%, var(--color-card-back-secondary) 100%);
    color: var(--color-white);
    display: flex;
    justify-content: center;
    align-items: center;
}

.card-back::after {
    content: "";
    background-image: url("https://koifluence.com/images/Koi.webp");
    background-size: 60%;
    background-repeat: no-repeat;
    background-position: center;
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
}

.card-back::before {
    display: none;
}

.card-face {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.card-suit {
    font-size: var(--space-2xl);
    line-height: 1;
}

.card.hearts,
.card.diamonds {
    color: var(--color-hearts-diamonds);
}

.card.spades,
.card.clubs {
    color: var(--color-spades-clubs);
}

.deck-container {
    margin: var(--space-lg) 0;
}

.deck {
    position: relative;
    cursor: pointer;
    transition: transform var(--transition-fast);
}

.deck:hover {
    transform: scale(1.05);
}

.controls {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
    margin: var(--space-lg) 0;
}

.btn {
    padding: 0.625rem var(--space-xl);
    border: none;
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-transform: uppercase;
    letter-spacing: 0.03125rem;
    min-width: 5rem;
    font-family: inherit;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.btn:not(:disabled):hover {
    transform: translateY(-0.125rem);
    box-shadow: var(--shadow-md);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-btn-primary-start) 0%, var(--color-btn-primary-end) 100%);
    color: var(--color-spades-clubs);
    box-shadow: var(--shadow-accent);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--color-btn-secondary-start) 0%, var(--color-btn-secondary-end) 100%);
    color: var(--color-white);
    box-shadow: var(--shadow-secondary);
}

.btn-accent {
    background: linear-gradient(135deg, var(--color-push) 0%, #e67e22 100%);
    color: var(--color-white);
    box-shadow: 0 0.25rem 0.5rem rgba(243, 156, 18, 0.3);
}

.message-area {
    text-align: center;
    margin: var(--space-lg) 0;
}

.game-message {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--color-accent);
    text-shadow: 0.0625rem 0.0625rem 0.125rem rgba(0, 0, 0, 0.5);
    min-height: var(--space-4xl);
    display: flex;
    align-items: center;
    justify-content: center;
}

.game-message.win {
    color: var(--color-win);
    animation: pulse 1.5s infinite;
}

.game-message.lose {
    color: var(--color-lose);
    animation: shake 0.5s ease-in-out;
}

.game-message.push {
    color: var(--color-push);
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

@keyframes shake {
    0%, 100% {
        transform: translateX(0);
    }
    25% {
        transform: translateX(-0.1875rem);
    }
    75% {
        transform: translateX(0.1875rem);
    }
}

@media (min-width: 480px) {
    .game-container {
        max-width: 31.25rem;
    }
    
    header h1 {
        font-size: var(--font-size-5xl);
    }
    
    .card {
        width: var(--card-width-tablet);
        height: var(--card-height-tablet);
        padding: var(--space-sm);
        font-size: 0.8125rem;
    }
    
    .card-suit {
        font-size: 1.75rem;
    }
    
    .cards-area {
        gap: 0.625rem;
        min-height: 6.875rem;
    }
    
    .btn {
        padding: var(--space-md) var(--space-2xl);
        font-size: var(--font-size-base);
        min-width: 6.25rem;
    }
    
    .game-message {
        font-size: var(--font-size-lg);
    }
}

@media (min-width: 768px) {
    .game-container {
        max-width: 43.75rem;
    }
    
    header h1 {
        font-size: var(--font-size-6xl);
    }
    
    .game-board {
        gap: var(--space-3xl);
    }
    
    .hands-container {
        flex-direction: row;
        justify-content: center;
        gap: var(--space-3xl);
    }
    
    .card {
        width: var(--card-width-desktop);
        height: var(--card-height-desktop);
        padding: var(--space-sm);
        font-size: var(--font-size-base);
    }
    
    .card-suit {
        font-size: var(--space-4xl);
    }
    
    .cards-area {
        gap: 0.625rem;
        min-height: 8.75rem;
    }
    
    .player-info h2 {
        font-size: var(--font-size-3xl);
    }
    
    .score {
        font-size: var(--font-size-xl);
    }
    
    .controls {
        gap: 0.9375rem;
        margin: var(--space-xl) 0;
    }
    
    .btn {
        min-width: 7.5rem;
    }
    
    .game-message {
        font-size: var(--font-size-2xl);
        min-height: var(--space-5xl);
    }
}

@media (min-width: 1024px) {
    .game-container {
        max-width: 62.5rem;
    }
    
    .cards-area {
        gap: 0.625rem;
    }
}