:root {
    --primary: #4F46E5;
    --primary-hover: #4338ca;
    --secondary: #10B981;
    --danger: #EF4444;
    --bg: #F3F4F6;
    --card-bg: #FFFFFF;
    --text: #1F2937;
    --text-light: #6B7280;
    --border: #D1D5DB;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    color: var(--text);
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
    min-height: 100vh;
}

.container {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    max-width: 500px;
    width: 100%;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

h1 {
    font-size: 2rem;
    font-weight: 700;
    margin: 0;
    color: var(--primary);
}

p {
    color: var(--text-light);
    margin-top: 0.5rem;
}

.controls {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.btn {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    background: white;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn:hover {
    background: #F9FAFB;
}

.btn.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.btn.primary {
    background: var(--primary);
    color: white;
    border: none;
    width: 100%;
}

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

.btn.secondary {
    color: var(--text);
}

.btn.danger {
    background: white;
    color: var(--danger);
    border-color: var(--danger);
}

.btn.danger:hover {
    background: #FEF2F2;
}

#grid-container {
    display: grid;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    justify-content: center;
}

.grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.grid-5 {
    grid-template-columns: repeat(5, 1fr);
}

.cell {
    width: 3rem;
    height: 3rem;
    font-size: 1.5rem;
    text-align: center;
    border: 2px solid var(--border);
    border-radius: 0.5rem;
    text-transform: uppercase;
    font-weight: 700;
}

.cell:focus {
    outline: none;
    border-color: var(--primary);
}

.actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

#results-area {
    border-top: 1px solid var(--border);
    padding-top: 1.5rem;
}

#results-area h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    display: flex;
    justify-content: space-between;
}

#word-count {
    font-size: 0.875rem;
    color: var(--text-light);
    background: #E5E7EB;
    padding: 0.2rem 0.6rem;
    border-radius: 999px;
}

.results-header {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    background: #F3F4F6;
    border-radius: 0.5rem;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

#results-list {
    list-style: none;
    padding: 0;
    margin: 0;
    max-height: 300px;
    overflow-y: auto;
}

.result-item {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    border-bottom: 1px solid #E5E7EB;
}

.result-score {
    color: var(--danger);
    font-weight: 700;
}

.hidden {
    display: none !important;
}

/* Loading Spinner */
#loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 50;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #E5E7EB;
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}