:root {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --accent-blue: #38bdf8;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --amber-accent: #f59e0b;
    --green-accent: #22c55e;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    user-select: none;
    -webkit-user-select: none;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 12px;
}

.game-container {
    width: 100%;
    max-width: 480px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Header */
.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.game-header h1 {
    font-size: 1.6rem;
    color: var(--accent-blue);
    letter-spacing: 1px;
}

.subtitle {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.icon-btn {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
}

/* Status Bar */
.status-bar {
    display: flex;
    justify-content: space-around;
    align-items: center;
    background: var(--card-bg);
    padding: 10px 14px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    font-size: 0.9rem;
    font-weight: bold;
}

.stat-item span:first-child {
    color: var(--text-muted);
    font-weight: normal;
}

/* Main Puzzle Area */
.puzzle-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    background: var(--card-bg);
    padding: 20px 16px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

/* Answer Slots */
.slots-container {
    display: flex;
    justify-content: center;
    gap: 8px;
    min-height: 52px;
    flex-wrap: wrap;
}

.letter-slot {
    width: 44px;
    height: 48px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.4rem;
    font-weight: bold;
    color: var(--text-main);
    background: #0f172a;
    transition: all 0.2s ease;
}

.letter-slot.filled {
    border-color: var(--accent-blue);
    color: var(--accent-blue);
}

.letter-slot.revealed {
    border-color: var(--amber-accent);
    color: var(--amber-accent);
}

/* Toast Message */
.toast {
    font-size: 0.9rem;
    font-weight: bold;
    padding: 6px 16px;
    border-radius: 20px;
    background: rgba(56, 189, 248, 0.15);
    color: var(--accent-blue);
    border: 1px solid var(--accent-blue);
}

.toast.hidden {
    opacity: 0;
    pointer-events: none;
}

/* Circular Wheel Layout */
.wheel-container {
    position: relative;
    width: 230px;
    height: 230px;
    margin: 8px 0;
}

.letter-wheel {
    position: relative;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    border: 2px dashed var(--border-color);
}

.wheel-node {
    position: absolute;
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background: #0f172a;
    border: 2px solid var(--accent-blue);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.2rem;
    cursor: pointer;
    transform: translate(-50%, -50%);
    transition: transform 0.2s ease, background 0.2s ease, opacity 0.2s ease;
}

.wheel-node:active {
    transform: translate(-50%, -50%) scale(0.92);
}

.wheel-node.used {
    opacity: 0.25;
    border-color: var(--border-color);
    cursor: default;
}

/* Action Buttons */
.action-bar {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    width: 100%;
}

.action-btn {
    padding: 10px 0;
    background: #0f172a;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    border-radius: 8px;
    font-weight: bold;
    font-size: 0.8rem;
    cursor: pointer;
}

.primary-btn {
    background: var(--accent-blue);
    color: #0f172a;
    border: none;
}

.hint-btn {
    border-color: var(--amber-accent);
    color: var(--amber-accent);
}

/* Controls Bar */
.control-bar {
    display: flex;
    gap: 10px;
}

.secondary-btn {
    flex: 1;
    padding: 12px 0;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    border-radius: 8px;
    font-weight: bold;
    font-size: 0.95rem;
    cursor: pointer;
}

/* Footer */
.game-footer {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.75rem;
}

/* Guide Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.75);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 100;
}

.modal-overlay.hidden {
    display: none;
}

.modal-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 24px;
    border-radius: 12px;
    max-width: 400px;
    width: 90%;
    display: flex;
    flex-direction: column;
    gap: 16px;
    color: var(--text-main);
}

.guide-content {
    display: flex;
    flex-direction: column;
    gap: 10px;
    font-size: 0.9rem;
    line-height: 1.5;
    color: #cbd5e1;
}

.guide-content hr {
    border: none;
    border-top: 1px solid var(--border-color);
}

.guide-content ul {
    padding-left: 18px;
}

.modal-btn {
    background: var(--accent-blue);
    color: #0f172a;
    border: none;
    padding: 10px 0;
    border-radius: 6px;
    font-weight: bold;
    cursor: pointer;
}