:root {
    --bg-color: #0b0c10;
    --panel-bg: rgba(21, 23, 34, 0.5);
    --panel-border: rgba(255, 255, 255, 0.05);
    --btn-bg: #191b28;
    --text-main: #ffffff;
    --text-muted: #6b6e7a;
    --glow-purple: #7b2cbf;
    --glow-pink: #ff006e;
    --glow-orange: #ff8c00;
    --text-pink: #d92662;
    --scifi-neon-blue: #00f2fe;
}

body.light-mode {
    --bg-color: #e2e8f0;
    --panel-bg: rgba(255, 255, 255, 0.7);
    --panel-border: rgba(0, 0, 0, 0.1);
    --btn-bg: #f8fafc;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --scifi-neon-blue: #0ea5e9;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: 'Poppins', sans-serif;
    transition: background-color 0.4s ease, color 0.4s ease;
    overflow-x: hidden;
    position: relative;
    cursor: default; /* منع تداخل مؤشرات الماوس الكثيرة */
}


/* ================= الثيمات وتخصيص الألوان (Themes) ================= */
body.theme-matrix {
    --glow-purple: #00ff00;
    --glow-pink: #00cc00;
    --glow-orange: #008800;
    --text-pink: #00ff00;
    --scifi-neon-blue: #00ff00;
}

body.theme-cyberpunk {
    --glow-purple: #fce205;
    --glow-pink: #00ffff;
    --glow-orange: #ff00ff;
    --text-pink: #00ffff;
    --scifi-neon-blue: #fce205;
}

body.theme-ocean {
    --glow-purple: #00b4d8;
    --glow-pink: #0077b6;
    --glow-orange: #03045e;
    --text-pink: #90e0ef;
    --scifi-neon-blue: #00b4d8;
}

#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1; /* خلف كل المحتوى */
    pointer-events: none; /* لا تتداخل مع الضغطات */
}

/* عنصر الماوس المضيء ( Cursor Glow ) */
#cursor-glow {
    position: fixed;
    width: 250px;
    height: 250px;
    background: radial-gradient(circle, rgba(123, 44, 191, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
    z-index: 9999; /* فوق كل شيء */
    filter: blur(40px);
    opacity: 0;
    transition: opacity 0.3s ease;
    transform: translate(-50%, -50%); /* للمركزة حول الماوس */
}
body:hover #cursor-glow {
    opacity: 1; /* يظهر فقط عند دخول الماوس للجسم */
}

/* كلاسات منع التوهج والوضع الفاتح بتاعة المرة اللي فاتت (مهمة جداً) */
.calc-glow-wrapper.no-glow {
    background: var(--panel-border) !important;
    box-shadow: none !important;
}



/* ================= زر الصوت (Voice) وزر المسح (Backspace) ================= */
.btn-voice {
    position: absolute;
    top: 15px;
    left: 15px;
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.1rem;
    transition: all 0.3s ease;
    cursor: pointer;
    z-index: 10;
}
.btn-voice:hover, .btn-voice.listening {
    color: var(--scifi-neon-blue);
    text-shadow: 0 0 10px var(--scifi-neon-blue);
}
.btn-voice.listening {
    animation: pulseMic 1.5s infinite;
}
@keyframes pulseMic {
    0% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.7; }
    100% { transform: scale(1); opacity: 1; }
}

.btn-backspace {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    padding: 0 10px 10px 0;
    transition: 0.2s;
    cursor: pointer;
}
.btn-backspace:hover {
    color: var(--glow-pink);
}

.draggable-panel {
    position: absolute; 
    cursor: default;
}

.drag-handle {
    cursor: grab; 
    user-select: none; 
    color: var(--text-muted);
    transition: color 0.3s ease;
}
.drag-handle:hover {
    color: var(--scifi-neon-blue);
}
.draggable-panel.dragging {
    opacity: 0.8;
    cursor: grabbing; 
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.5);
    z-index: 2000;
}


.text-main { color: var(--text-main) !important; }

.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--panel-border);
    border-radius: 20px;
    padding: 25px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    transition: background 0.4s ease, border-color 0.4s ease;
}

.calc-glow-wrapper {
    background: linear-gradient(135deg, var(--glow-purple) 0%, var(--glow-pink) 50%, var(--glow-orange) 100%);
    padding: 2px;
    border-radius: 30px;
    box-shadow: -15px -15px 40px rgba(123, 44, 191, 0.15), 15px 15px 40px rgba(255, 140, 0, 0.1);
    transition: all 0.4s ease;
}


.calc-glow-wrapper.no-glow {
    background: var(--panel-border);
    box-shadow: none;
}


.top-navbar {
    background: transparent;
    border-bottom: 1px solid var(--panel-border);
    padding-top: 15px;
    padding-bottom: 15px;
}

.logo-icon {
    color: var(--glow-pink);
    font-size: 1.5rem;
    text-shadow: 0 0 10px rgba(255, 0, 110, 0.5);
}

.logo-text {
    font-weight: 600;
    letter-spacing: 1px;
    color: #fff;
}

.nav-pills-custom .nav-link {
    color: var(--text-muted);
    border-radius: 12px;
    padding: 8px 16px;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.nav-pills-custom .nav-link.active,
.nav-pills-custom .nav-link:hover {
    background: rgba(123, 44, 191, 0.2);
    color: #fff;
    border: 1px solid rgba(123, 44, 191, 0.5);
}

.calc-glow-wrapper {
    background: linear-gradient(135deg, var(--glow-purple) 0%, var(--glow-pink) 50%, var(--glow-orange) 100%);
    padding: 2px;
    border-radius: 30px;
    box-shadow: -15px -15px 40px rgba(123, 44, 191, 0.15), 15px 15px 40px rgba(255, 140, 0, 0.1);
    position: relative;
    z-index: 1;
}



.screen {
    text-align: right;
    margin-bottom: 30px;
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
}

.history-text { color: var(--text-muted); font-size: 1rem; min-height: 24px; letter-spacing: 1px; }
.current-text { font-size: 3.5rem; font-weight: 500; margin: 0; line-height: 1.2; letter-spacing: 2px; }

.keypad {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px; 
    transition: all 0.4s ease;
}
.keypad.scientific-mode { grid-template-columns: repeat(5, 1fr); }


.btn-calc {
    background: var(--btn-bg);
    color: var(--text-main);
    border: 1px solid rgba(255, 255, 255, 0.03);
    border-radius: 14px;
    height: 55px;
    font-size: 1.3rem;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; user-select: none; transition: all 0.2s ease;
    box-shadow: -2px -2px 6px rgba(255, 255, 255, 0.02), 4px 4px 10px rgba(0, 0, 0, 0.2);
}
.btn-calc:active {
    transform: scale(0.95);
    box-shadow: inset 3px 3px 10px rgba(0, 0, 0, 0.6);
}

.btn-operator { background: linear-gradient(180deg, #ff8c00 0%, #cc5500 100%); box-shadow: 0 4px 15px rgba(255, 140, 0, 0.3); border: none; }
.btn-equals { background: linear-gradient(180deg, #ff006e 0%, #b3004d 100%); box-shadow: 0 4px 15px rgba(255, 0, 110, 0.3); border: none; }
.btn-zero { grid-column: span 2; justify-content: flex-start; padding-left: 30px; }
.btn-action { background: #262938; }

.custom-switch {
    width: 40px !important;
    height: 20px !important;
    background-color: #2a2d3e !important;
    border: none !important;
    cursor: pointer;
    box-shadow: inset 0 0 5px rgba(0,0,0,0.5);
}

.custom-switch:checked {
    background-color: var(--glow-purple) !important;
    box-shadow: 0 0 10px rgba(123, 44, 191, 0.5), inset 0 0 5px rgba(0,0,0,0.5);
}

.custom-radio .form-check-input {
    background-color: transparent;
    border-color: var(--glow-purple);
}

.custom-radio .form-check-input:checked {
    background-color: var(--glow-purple);
    border-color: var(--glow-purple);
    box-shadow: 0 0 8px rgba(123, 44, 191, 0.6);
}

.fs-7 { font-size: 0.85rem; }
.text-pink { color: var(--text-pink); }

.btn-outline-custom {
    border: 1px solid var(--panel-border);
    background: rgba(255, 255, 255, 0.02);
    border-radius: 12px;
    padding: 10px;
    font-size: 0.85rem;
    transition: 0.3s;
}

.btn-outline-custom:hover {
    background: rgba(255, 255, 255, 0.05);
    color: #fff !important;
}

.footer {
    border-top: 1px solid var(--panel-border);
    background: transparent;
}

.social-icons a {
    color: var(--text-muted);
    transition: 0.3s;
    font-size: 1.1rem;
}

.social-icons a:hover {
    color: #fff;
}

.btn-backspace {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    padding: 0 10px 10px 0;
    transition: all 0.2s ease;
    cursor: pointer;
}
.btn-backspace:hover {
    color: var(--glow-pink);
    transform: scale(1.1);
}
.btn-backspace:active {
    transform: scale(0.9);
}

.history-item {
    padding-left: 15px;
    border-left: 2px solid var(--glow-purple);
    position: relative;
}
.history-item::before {
    content: '';
    position: absolute;
    left: -5px;
    top: 5px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--glow-purple);
    box-shadow: 0 0 8px var(--glow-purple);
}


.calc-inner {
    background: var(--panel-bg);
    backdrop-filter: blur(25px);
    border-radius: 28px;
    padding: 25px;
    width: 100%;
    min-width: 400px; 
    max-width: 450px; 
    height: auto;
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.3);
    transition: all 0.4s ease-out;
}

.screen { 
    text-align: right; 
    margin-bottom: 20px;
    min-height: 90px; 
    height: fit-content; 
    display: flex; 
    flex-direction: column; 
    justify-content: flex-end;
    transition: height 0.3s ease;
}

.current-text { 
    font-size: 3rem;
    font-weight: 500; 
    margin: 0; 
    line-height: 1.2; 
    letter-spacing: 2px; 
    color: var(--text-main);
    word-break: break-all; 
    white-space: pre-wrap;
    transition: all 0.2s ease;
}

.history-text { 
    color: var(--text-muted); 
    font-size: 1rem; 
    min-height: 24px; 
    letter-spacing: 1px;
    word-break: break-all; 
    white-space: pre-wrap;
}


@media (max-width: 1199px) {
    .drag-handle { cursor: default; }
    .draggable-panel { position: relative !important; left: 0 !important; top: 0 !important; }
    .fixed-panel-container { position: relative; z-index: 1; }
}

@media (min-width: 1200px) {

    .fixed-panel-container { position: static; width: auto; }
    #history-sidebar { left: calc(50% - 630px); top: 20px; }
    #prefs-sidebar { right: calc(50% - 630px); top: 20px; }

}