/* ── Reset & Base ── */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow: hidden;
    overscroll-behavior: none;
    background: #12121f;
    font-family: 'Segoe UI', system-ui, sans-serif;
    user-select: none;
    -webkit-user-select: none;
    touch-action: none;
    -webkit-touch-callout: none;
}

/* ── Layout ── */
#app {
    display: flex;
    flex-direction: column;
    height: 100dvh;
    height: 100vh; /* fallback */
}

#header {
    flex-shrink: 0;
    padding: 6px 12px;
    text-align: center;
    background: linear-gradient(to bottom, #1a1a2e, #12121f);
}

#header h1 {
    font-size: 16px;
    font-weight: 300;
    letter-spacing: 3px;
    color: #8888aa;
}

.hint {
    font-size: 11px;
    color: #555;
    margin-top: 2px;
}

/* ── Piano Container ── */
#piano {
    flex: 1;
    display: flex;
    position: relative;
    background: #1a1a2e;
    min-height: 0; /* allow flex shrink */
}

/* ── White Keys ── */
.key {
    -webkit-tap-highlight-color: transparent;
    cursor: pointer;
    transition: background 0.06s, box-shadow 0.06s;
}

.key.white {
    flex: 1;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding-bottom: 10px;
    background: linear-gradient(to bottom, #fefefe 0%, #f5f3ef 60%, #e8e5e0 100%);
    border-left: 1px solid #c5c0ba;
    border-bottom: 1px solid #b0aba5;
    border-radius: 0 0 5px 5px;
    box-shadow:
        -1px 0 0 #d8d4d0 inset,
        0 -2px 4px rgba(0, 0, 0, 0.06) inset,
        0 3px 5px rgba(0, 0, 0, 0.25);
    z-index: 1;
}

.key.white:first-child {
    border-left: none;
}

.key.white.active {
    background: linear-gradient(to bottom, #d8e4f8, #c0d0e8);
    box-shadow:
        0 1px 2px rgba(0, 0, 0, 0.2),
        0 0 12px rgba(100, 160, 255, 0.2) inset;
}

/* ── Black Keys ── */
.key.black {
    position: absolute;
    top: 0;
    height: 58%;
    z-index: 2;
    background: linear-gradient(to bottom, #3a3a42 0%, #222228 40%, #111115 100%);
    border: 1px solid #000;
    border-top: none;
    border-radius: 0 0 4px 4px;
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.5),
        0 1px 0 rgba(255, 255, 255, 0.06) inset,
        0 -3px 4px rgba(0, 0, 0, 0.4) inset;
}

.key.black.active {
    background: linear-gradient(to bottom, #505058, #333338);
    box-shadow:
        0 2px 3px rgba(0, 0, 0, 0.4),
        0 -1px 2px rgba(0, 0, 0, 0.3) inset;
}

/* ── Labels ── */
.key-label {
    font-size: 10px;
    color: #aaa;
    pointer-events: none;
    line-height: 1;
}

.key.white.active .key-label {
    color: #5577aa;
}

/* ── Landscape (optimizado para celular girado) ── */
@media (orientation: landscape) {
    #header {
        padding: 3px 8px;
    }
    #header h1 {
        font-size: 13px;
    }
    .hint {
        display: none;
    }
    .key.black {
        height: 55%;
    }
}

/* ── Portrait ── */
@media (orientation: portrait) {
    .key.black {
        height: 52%;
    }
    .key-label {
        font-size: 9px;
    }
}

/* ── Pantallas pequeñas ── */
@media (max-width: 480px) {
    .key-label {
        font-size: 8px;
    }
    #header h1 {
        font-size: 13px;
        letter-spacing: 2px;
    }
}

/* ── Ocultar hint en touch ── */
@media (hover: none) and (pointer: coarse) {
    .hint {
        display: none;
    }
}