:root {
    --red: #e7153b;
    --yellow: #ffc400;
    --green: #3cac2c;
    --blue: #1a61b3;
    --spacing: 1rem;
}

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

body {
    min-height: 100vh;
    font-family: 'Segoe UI', Arial, sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    padding: var(--spacing);
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    overflow: hidden;
}

.header {
    padding: var(--spacing);
    background: #333;
    color: white;
    text-align: center;
}

.board {
    padding: var(--spacing);
    position: relative;
    background: none;
    overflow-x: auto; /* Add horizontal scrolling for narrow screens */
    -webkit-overflow-scrolling: touch; /* Smooth scrolling on mobile */
    overflow-y: hidden; /* Prevent vertical scrolling unless necessary */
}

.notice {
    position: absolute;
    right: var(--spacing);
    top: var(--spacing);
    padding: 0.5rem 1rem;
    background: rgba(0,0,0,0.7);
    color: white;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: bold;
    pointer-events: none;
    width: auto;
}

.color {
    display: -webkit-box; /* Safari/Chrome -webkit- prefix */
    display: -ms-flexbox; /* IE10 */
    display: flex;
    flex-direction: row-reverse;
    padding: 0.75rem;
    margin-bottom: 0.5rem;
    border-radius: 8px;
    transition: transform 0.2s ease;
    overflow: hidden;
    position: relative;
    flex-wrap: nowrap; /* Prevent wrapping on mobile */
    min-width: 100%; /* Ensure the row takes full width, allowing horizontal scroll if needed */
    white-space: nowrap; /* Prevent text wrapping within the row */
    justify-content: center; /* Center the flex items horizontally */
    -webkit-justify-content: center; /* Safari/Chrome -webkit- prefix */
    -ms-flex-pack: center; /* IE10 */
}

.color:hover {
    transform: translateY(-2px);
    -webkit-transform: translateY(-2px); /* Safari/Chrome -webkit- prefix */
    -ms-transform: translateY(-2px); /* IE10 */
}

.red { background: var(--red); }
.yellow { background: var(--yellow); }
.green { background: var(--green); }
.blue { background: var(--blue); }

.red .number, .red .lock { background: rgba(255,255,255,0.9); color: var(--red); }
.yellow .number, .yellow .lock { background: rgba(255,255,255,0.9); color: var(--yellow); }
.green .number, .green .lock { background: rgba(255,255,255,0.9); color: var(--green); }
.blue .number, .blue .lock { background: rgba(255,255,255,0.9); color: var(--blue); }

.number, .lock {
    position: relative;
    height: 2.5rem;
    width: 2.5rem;
    margin: 0.25rem;
    font-size: 1.2em;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.number:hover, .lock:hover {
    background: white;
    transform: scale(1.05);
    -webkit-transform: scale(1.05); /* Safari/Chrome -webkit- prefix */
    -ms-transform: scale(1.05); /* IE10 */
}

.number i, .lock i {
    position: absolute;
    top: 50%;
    right: 50%;
    transform: translate(50%, -50%);
    -webkit-transform: translate(50%, -50%); /* Safari/Chrome -webkit- prefix */
    -ms-transform: translate(50%, -50%); /* IE10 */
}

.number i {
    display: none;
    color: black;
}

.lock {
    width: 2.5rem;
    margin-left: 0.5rem;
    border-radius: 50%;
    z-index: 3;
}

.lock [class$="lock"] {
    display: none;
}

/* Strikethrough effect */
.color input[type="checkbox"][id$="-lock"]:checked ~ .number::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    width: 100%;
    height: 2px;
    background: rgba(0, 0, 0, 0.5);
    transform: translateY(-50%);
    -webkit-transform: translateY(-50%); /* Safari/Chrome -webkit- prefix */
    -ms-transform: translateY(-50%); /* IE10 */
    z-index: 1;
}

.color input[type="checkbox"] {
    display: none;
}

.color input[type="checkbox"]:checked + label {
    background: white;
}

.color input[type="checkbox"]:checked + label span {
    display: none;
}

.color input[type="checkbox"]:checked + label i {
    display: block;
}

.color input[type="checkbox"]:checked[id$="-lock"] + label [class*="-unlock"] {
    display: none;
}

.color input[type="checkbox"]:checked[id$="-lock"] + label [class*="-lock"] {
    display: block;
}

.scoring {
    padding: var(--spacing);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #f8f9fa;
    flex-wrap: wrap;
}

.strikes {
    text-align: center;
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

.strikes input {
    display: none;
}

.strikes input + label {
    display: inline-block;
    width: 2rem;
    height: 2rem;
    margin: 0.25rem;
    background: #ddd;
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.2s ease;
}

.strikes input:checked + label {
    background: var(--red);
}

h2 {
    margin: 0;
    font-size: 1.5em;
    text-align: center;
}

h3 {
    margin: 0 0 0.5rem;
    font-size: 1.25em;
    font-weight: 500;
    text-align: center;
    text-transform: uppercase;
}

button {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    background: #333;
    color: white;
    cursor: pointer;
    transition: background 0.2s ease;
}

button:hover {
    background: #555;
}

.saved-score ul {
    list-style-type: none;
    padding: 0;
    margin: 0.5rem 0;
}

.saved-score li {
    margin: 0.25rem 0;
    font-size: 0.9em;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.saved-score .delete-score {
    padding: 0.2rem 0.5rem;
    border: none;
    border-radius: 4px;
    background: #e7153b;
    color: white;
    font-size: 0.8em;
    cursor: pointer;
    margin-left: 0.5rem;
    transition: background 0.2s ease;
}

.saved-score .delete-score:hover {
    background: #ff4444;
}

footer {
    padding: var(--spacing);
    text-align: center;
    font-family: Avenir, Verdana, 'Helvetica Neue', sans-serif;
    font-style: italic;
    opacity: 0.4;
}

@media (max-width: 600px) {
    .color {
        flex-wrap: nowrap; /* Force no wrapping on mobile */
        min-width: 100%; /* Ensure full width, allowing horizontal scroll */
    }
    .number, .lock {
        height: 2rem;
        width: 2rem;
        font-size: 1em;
    }
    .scoring {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    .strikes {
        flex-direction: row;
        justify-content: center;
    }
    .notice {
        font-size: 0.8em;
    }
    .board {
        min-width: 100%; /* Ensure the board takes full width for horizontal scroll */
    }
}