/* ===========================
   DESIGN SYSTEM & BASE
   =========================== */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    background: #07070d;
    overflow: hidden;
    font-family: 'Tajawal', 'Inter', sans-serif;
    color: #fff;
    height: 100vh;
    width: 100vw;
    transition: filter 0.3s ease;
}

body.inverted {
    filter: invert(1);
}

canvas {
    display: block;
    position: absolute;
    top: 0; left: 0;
    z-index: 1;
}

#waveCanvas {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 2;
    pointer-events: none;
}

/* ===========================
   TAP PROMPT
   =========================== */
#tap-prompt {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 20;
    transition: opacity 1s ease;
    pointer-events: none;
}

#tap-prompt h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: 4px;
    background: linear-gradient(135deg, #00f0ff, #8b5cf6, #ff006e);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.8rem;
    animation: breathe 2.5s ease-in-out infinite;
}

#tap-prompt p {
    font-size: 1rem;
    color: rgba(255,255,255,0.35);
    letter-spacing: 1px;
}

@keyframes breathe {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

/* ===========================
   TOP BAR (rec + shape)
   =========================== */
#top-bar {
    position: absolute;
    top: 14px; left: 20px;
    z-index: 20;
    display: none;
    align-items: center;
    gap: 10px;
}

#rec-indicator {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(0,0,0,0.5);
    border: 1px solid rgba(255,255,255,0.08);
    padding: 6px 16px;
    border-radius: 40px;
    backdrop-filter: blur(15px);
}

#rec-indicator .dot {
    width: 8px; height: 8px;
    background: #ff3b5c;
    border-radius: 50%;
    animation: pulse-dot 1.2s ease-in-out infinite;
    box-shadow: 0 0 6px #ff3b5c;
}

#rec-indicator span {
    font-size: 0.65rem;
    letter-spacing: 2px;
    color: rgba(255,255,255,0.5);
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.3; transform: scale(0.7); }
}

#shape-name {
    font-size: 0.55rem;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: rgba(255,255,255,0.12);
}

/* ===========================
   STUDY HUD — Spread Layout
   =========================== */
#study-hud {
    position: absolute;
    inset: 0;
    z-index: 20;
    display: none;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.5s ease;
}

/* Timer — TOP CENTER */
#timer-box {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    pointer-events: auto;
}

#timer-label {
    font-size: 0.8rem;
    letter-spacing: 4px;
    color: rgba(255,255,255,0.4);
    margin-bottom: 4px;
}

#timer {
    font-family: 'Inter', monospace;
    font-size: 3.2rem;
    font-weight: 900;
    letter-spacing: 4px;
    background: linear-gradient(135deg, #00f0ff, #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: none;
    filter: drop-shadow(0 0 20px rgba(0,240,255,0.3));
}

/* Level & XP — BOTTOM LEFT */
#level-box {
    position: absolute;
    bottom: 24px;
    left: 24px;
    background: rgba(0,0,0,0.5);
    border: 1px solid rgba(251,191,36,0.15);
    border-radius: 16px;
    padding: 16px 22px;
    backdrop-filter: blur(20px);
    min-width: 200px;
    pointer-events: auto;
}

#level-label {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
    margin-bottom: 10px;
}

#level-num {
    font-weight: 900;
    font-size: 2rem;
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

#xp-bar-bg {
    width: 100%;
    height: 8px;
    background: rgba(255,255,255,0.08);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 8px;
}

#xp-bar-fill {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, #8b5cf6, #00f0ff, #8b5cf6);
    background-size: 200% 100%;
    animation: xpShimmer 2s ease-in-out infinite;
    border-radius: 4px;
    transition: width 0.8s ease;
}

@keyframes xpShimmer {
    0% { background-position: 0% 0; }
    100% { background-position: 200% 0; }
}

#xp-text {
    font-size: 0.75rem;
    color: rgba(255,255,255,0.4);
    text-align: center;
    font-family: 'Inter', sans-serif;
}

/* Stats Row — BOTTOM RIGHT */
#stats-row {
    position: absolute;
    bottom: 24px;
    right: 24px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    pointer-events: auto;
}

.stat-item {
    background: rgba(0,0,0,0.5);
    border: 1px solid rgba(255,255,255,0.06);
    border-radius: 14px;
    padding: 14px 18px;
    text-align: center;
    backdrop-filter: blur(15px);
    min-width: 90px;
}

.stat-value {
    font-family: 'Inter', sans-serif;
    font-size: 1.5rem;
    font-weight: 900;
    color: rgba(255,255,255,0.95);
    margin-bottom: 4px;
}

.stat-label {
    font-size: 0.7rem;
    color: rgba(255,255,255,0.4);
    letter-spacing: 1px;
}

/* ===========================
   QUOTE BOX — Center, Large
   =========================== */
#quote-box {
    position: absolute;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 20;
    max-width: 750px;
    width: 80%;
    text-align: center;
    display: none;
}

#quote-text {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, rgba(139,92,246,1), rgba(0,240,255,1), rgba(255,0,110,0.8));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 2;
    letter-spacing: 1px;
    transition: opacity 0.6s ease;
    filter: drop-shadow(0 0 25px rgba(139,92,246,0.4));
    animation: quoteGlow 3s ease-in-out infinite;
}

@keyframes quoteGlow {
    0%, 100% { filter: drop-shadow(0 0 15px rgba(139,92,246,0.3)); }
    50% { filter: drop-shadow(0 0 40px rgba(0,240,255,0.5)); }
}

/* ===========================
   VOLUME BAR
   =========================== */
#volume-bar {
    position: absolute;
    bottom: 60px; left: 50%;
    transform: translateX(-50%);
    z-index: 20;
    display: none;
    align-items: center;
    gap: 3px;
    height: 24px;
}

.vol-segment {
    width: 3px;
    background: linear-gradient(to top, #8b5cf6, #00f0ff);
    border-radius: 2px;
    transition: height 0.05s ease;
    min-height: 2px;
}

/* ===========================
   CONTROLS HINT
   =========================== */
#controls-hint {
    position: absolute;
    bottom: 6px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 20;
    display: none;
    gap: 20px;
    font-size: 0.55rem;
    color: rgba(255,255,255,0.12);
    letter-spacing: 1px;
    font-family: 'Inter', sans-serif;
}

/* ===========================
   SCENE TOGGLE BUTTON
   =========================== */
#scene-nav {
    position: absolute;
    top: 20px;
    right: 20px;
    z-index: 25;
    display: none;
}

#scene-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    background: rgba(0,0,0,0.5);
    border: 1px solid rgba(139,92,246,0.3);
    color: rgba(255,255,255,0.7);
    padding: 10px 20px;
    font-size: 0.75rem;
    font-family: 'Tajawal', sans-serif;
    letter-spacing: 1px;
    border-radius: 30px;
    cursor: pointer;
    backdrop-filter: blur(15px);
    transition: all 0.3s ease;
}

#scene-toggle:hover {
    background: rgba(139,92,246,0.2);
    border-color: rgba(139,92,246,0.6);
    color: #fff;
    box-shadow: 0 0 20px rgba(139,92,246,0.3);
    transform: scale(1.05);
}

/* kbd elements in controls hint */
kbd {
    font-family: 'Inter', sans-serif;
    font-size: inherit;
    color: inherit;
    background: none;
    border: none;
    padding: 0;
}

/* ===========================
   RESPONSIVE — TABLET (≤768px)
   =========================== */
@media (max-width: 768px) {
    #tap-prompt h1 {
        font-size: 1.8rem;
        letter-spacing: 2px;
    }

    #tap-prompt p {
        font-size: 0.85rem;
    }

    /* Timer */
    #timer {
        font-size: 2.2rem;
        letter-spacing: 2px;
    }

    #timer-label {
        font-size: 0.7rem;
        letter-spacing: 2px;
    }

    /* Level box — move to bottom-center, full width */
    #level-box {
        left: 16px;
        right: 16px;
        bottom: auto;
        top: 80px;
        min-width: unset;
        padding: 12px 16px;
        border-radius: 12px;
    }

    #level-num {
        font-size: 1.5rem;
    }

    /* Stats row — reflow under level box */
    #stats-row {
        position: absolute;
        bottom: auto;
        top: 170px;
        right: 16px;
        left: 16px;
        grid-template-columns: repeat(4, 1fr);
        gap: 8px;
    }

    .stat-item {
        min-width: unset;
        padding: 10px 8px;
        border-radius: 10px;
    }

    .stat-value {
        font-size: 1.1rem;
    }

    .stat-label {
        font-size: 0.6rem;
    }

    /* Quote box */
    #quote-box {
        bottom: 70px;
        width: 90%;
        max-width: 500px;
    }

    #quote-text {
        font-size: 1.3rem;
        line-height: 1.8;
    }

    /* Scene toggle */
    #scene-nav {
        top: 14px;
        right: 14px;
    }

    #scene-toggle {
        padding: 8px 14px;
        font-size: 0.7rem;
    }

    /* Volume bar */
    #volume-bar {
        bottom: 45px;
    }

    /* Controls hint */
    #controls-hint {
        gap: 10px;
        font-size: 0.5rem;
        flex-wrap: wrap;
        justify-content: center;
        width: 90%;
    }
}

/* ===========================
   RESPONSIVE — PHONE (≤480px)
   =========================== */
@media (max-width: 480px) {
    #tap-prompt h1 {
        font-size: 1.4rem;
        letter-spacing: 1px;
    }

    #tap-prompt p {
        font-size: 0.75rem;
    }

    /* Top bar */
    #top-bar {
        top: 10px;
        left: 12px;
        gap: 6px;
    }

    #rec-indicator {
        padding: 4px 10px;
        border-radius: 30px;
    }

    #rec-indicator .dot {
        width: 6px;
        height: 6px;
    }

    #rec-indicator span {
        font-size: 0.55rem;
        letter-spacing: 1px;
    }

    #shape-name {
        font-size: 0.45rem;
    }

    /* Timer — shrink significantly */
    #timer-box {
        top: 12px;
    }

    #timer {
        font-size: 1.6rem;
        letter-spacing: 1px;
    }

    #timer-label {
        font-size: 0.6rem;
        letter-spacing: 1px;
        margin-bottom: 2px;
    }

    /* Level box — compact horizontal card */
    #level-box {
        top: 58px;
        left: 12px;
        right: 12px;
        padding: 10px 14px;
        border-radius: 10px;
        display: flex;
        align-items: center;
        gap: 12px;
        flex-wrap: wrap;
    }

    #level-label {
        font-size: 0.75rem;
        margin-bottom: 0;
        white-space: nowrap;
    }

    #level-num {
        font-size: 1.2rem;
    }

    #xp-bar-bg {
        flex: 1;
        min-width: 80px;
        height: 6px;
        margin-bottom: 0;
    }

    #xp-text {
        font-size: 0.6rem;
        width: 100%;
    }

    /* Stats row — 2x2 grid, positioned below level */
    #stats-row {
        top: 130px;
        left: 12px;
        right: 12px;
        grid-template-columns: 1fr 1fr;
        gap: 6px;
    }

    .stat-item {
        padding: 8px 6px;
        border-radius: 8px;
    }

    .stat-value {
        font-size: 0.95rem;
        margin-bottom: 2px;
    }

    .stat-label {
        font-size: 0.55rem;
        letter-spacing: 0.5px;
    }

    /* Quote box */
    #quote-box {
        bottom: 55px;
        width: 92%;
    }

    #quote-text {
        font-size: 1rem;
        line-height: 1.7;
        letter-spacing: 0;
    }

    /* Scene toggle */
    #scene-nav {
        top: 10px;
        right: 10px;
    }

    #scene-toggle {
        padding: 6px 12px;
        font-size: 0.65rem;
        border-radius: 24px;
    }

    /* Volume bar */
    #volume-bar {
        bottom: 36px;
        height: 18px;
    }

    /* Controls hint — hide on very small screens, touch replaces keyboard */
    #controls-hint {
        display: none !important;
    }
}