/* ============================================================
   Sudoku Generator – Frontend Styles
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Space+Mono:wght@400;700&family=DM+Sans:wght@400;500;600&display=swap');

/* ── Variables base ── */
.sudoku-wrapper {
    --sg-accent:        #22c55e;
    --sg-accent-dark:   #15803d;
    --sg-accent-light:  #dcfce7;
    --sg-accent-glow:   rgba(34,197,94,.25);
    --sg-cell-size:     clamp(28px, 4vw, 52px);
    --sg-font-mono:     'Space Mono', monospace;
    --sg-font-sans:     'DM Sans', sans-serif;
    --sg-border:        #e2e8f0;
    --sg-bg:            #ffffff;
    --sg-text:          #0f172a;
    --sg-given-bg:      var(--sg-accent-light);
    --sg-given-color:   var(--sg-accent-dark);
    --sg-box-border:    3px;

    font-family: var(--sg-font-sans);
    max-width: 900px;
    margin: 2rem auto;
    padding: 0 1rem;
}

/* ── Paletas de color ── */
.sg-color-green {
    --sg-accent:      #22c55e;
    --sg-accent-dark: #15803d;
    --sg-accent-light:#dcfce7;
    --sg-accent-glow: rgba(34,197,94,.25);
}
.sg-color-blue {
    --sg-accent:      #3b82f6;
    --sg-accent-dark: #1d4ed8;
    --sg-accent-light:#dbeafe;
    --sg-accent-glow: rgba(59,130,246,.25);
}
.sg-color-red {
    --sg-accent:      #ef4444;
    --sg-accent-dark: #b91c1c;
    --sg-accent-light:#fee2e2;
    --sg-accent-glow: rgba(239,68,68,.25);
}

/* ── Tarjeta ── */
.sudoku-wrapper {
    background: var(--sg-bg);
    border: 2px solid var(--sg-border);
    border-top: 5px solid var(--sg-accent);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 8px 32px rgba(0,0,0,.08), 0 0 0 1px rgba(0,0,0,.03);
    position: relative;
    overflow: hidden;
}
.sudoku-wrapper::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at 100% 0%, var(--sg-accent-glow) 0%, transparent 60%);
    pointer-events: none;
}

/* ── Cabecera ── */
.sg-header {
    display: flex;
    align-items: center;
    gap: .75rem;
    flex-wrap: wrap;
    margin-bottom: 1.25rem;
}
.sg-badge {
    font-family: var(--sg-font-mono);
    font-size: .7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .1em;
    padding: .25rem .75rem;
    border-radius: 100px;
    background: var(--sg-accent);
    color: #fff;
}
.sg-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--sg-text);
    flex: 1;
}
.sg-actions {
    display: flex;
    gap: .5rem;
    flex-wrap: wrap;
}
.sg-btn {
    font-family: var(--sg-font-sans);
    font-size: .8rem;
    font-weight: 600;
    padding: .4rem .9rem;
    border-radius: 8px;
    border: 2px solid var(--sg-accent);
    cursor: pointer;
    transition: background .15s, color .15s, transform .1s;
    background: transparent;
    color: var(--sg-accent-dark);
    line-height: 1.3;
}
.sg-btn:hover {
    background: var(--sg-accent);
    color: #fff;
    transform: translateY(-1px);
}
.sg-btn:active { transform: translateY(0); }
.sg-btn-solve { border-color: #94a3b8; color: #64748b; }
.sg-btn-solve:hover { background: #64748b; border-color: #64748b; color: #fff; }
.sg-btn-reset { border-color: #fca5a5; color: #ef4444; }
.sg-btn-reset:hover { background: #ef4444; border-color: #ef4444; color: #fff; }

/* ── Tablero ── */
.sg-board {
    display: grid;
    grid-template-columns: repeat(var(--sg-size), var(--sg-cell-size));
    grid-template-rows:    repeat(var(--sg-size), var(--sg-cell-size));
    gap: 1px;
    background: var(--sg-border);
    border: var(--sg-box-border) solid var(--sg-accent);
    border-radius: 10px;
    overflow: hidden;
    width: fit-content;
    margin: 0 auto;
    box-shadow: 0 4px 16px var(--sg-accent-glow);
}

/* ── Celdas ── */
.sg-cell {
    width:  var(--sg-cell-size);
    height: var(--sg-cell-size);
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--sg-font-mono);
    font-size: clamp(.6rem, 1.8vw, 1.1rem);
    font-weight: 700;
    background: var(--sg-bg);
    color: var(--sg-text);
    text-transform: uppercase;
    box-sizing: border-box;
    transition: background .12s, box-shadow .12s;
}

/* Entrada editable */
input.sg-cell {
    border: none;
    outline: none;
    text-align: center;
    cursor: text;
    caret-color: var(--sg-accent);
    -webkit-appearance: none;
    -moz-appearance: textfield;
}
input.sg-cell:focus {
    background: var(--sg-accent-light);
    box-shadow: inset 0 0 0 2px var(--sg-accent);
    z-index: 1;
    position: relative;
}
input.sg-cell:hover:not(:focus) {
    background: #f8fafc;
}

/* Dadas */
.sg-given {
    background: var(--sg-given-bg);
    color: var(--sg-given-color);
    cursor: default;
    user-select: none;
}

/* Bordes de caja */
.sg-box-right  { border-right:  var(--sg-box-border) solid var(--sg-accent); }
.sg-box-bottom { border-bottom: var(--sg-box-border) solid var(--sg-accent); }

/* ── Estados de validación ── */
.sg-cell.sg-error {
    background: #fee2e2 !important;
    color: #b91c1c !important;
    animation: sg-shake .3s ease;
}
.sg-cell.sg-correct {
    background: #dcfce7 !important;
    color: #15803d !important;
}

@keyframes sg-shake {
    0%,100% { transform: translateX(0); }
    25%      { transform: translateX(-3px); }
    75%      { transform: translateX(3px); }
}

/* ── Mensaje ── */
.sg-message {
    margin-top: 1rem;
    font-family: var(--sg-font-sans);
    font-size: .9rem;
    font-weight: 600;
    text-align: center;
    min-height: 1.5em;
    transition: opacity .3s;
}
.sg-message.sg-msg-ok  { color: #15803d; }
.sg-message.sg-msg-err { color: #b91c1c; }
.sg-message.sg-msg-info{ color: #1d4ed8; }

/* ── Responsive ── */
@media (max-width: 480px) {
    .sudoku-wrapper { padding: 1rem .5rem; }
    .sg-board {
        grid-template-columns: repeat(var(--sg-size), clamp(20px, 6vw, 36px));
        grid-template-rows:    repeat(var(--sg-size), clamp(20px, 6vw, 36px));
    }
    .sg-cell {
        width:  clamp(20px, 6vw, 36px);
        height: clamp(20px, 6vw, 36px);
    }
}

/* ── Editor preview ── */
.sg-editor-preview { pointer-events: none; }