/* ═══════════════════════════════════════════════════════════════════════════
   Thermal OS Calculator — Stylesheet
   Dropdown processor selector + inline thermal stats
   ═══════════════════════════════════════════════════════════════════════════ */

:root {
    --bg: #0a0e1a;
    --bg-calc: rgba(16, 20, 36, 0.92);
    --bg-display: rgba(8, 12, 24, 0.95);
    --bg-card: rgba(255,255,255,0.04);
    --bg-card-hover: rgba(255,255,255,0.08);
    --bg-btn: rgba(255,255,255,0.06);
    --bg-btn-hover: rgba(255,255,255,0.12);
    --bg-btn-active: rgba(255,255,255,0.18);
    --bg-util: rgba(6,182,212,0.12);
    --bg-util-hover: rgba(6,182,212,0.22);
    --bg-op: rgba(139,92,246,0.15);
    --bg-op-hover: rgba(139,92,246,0.28);
    --bg-eq: linear-gradient(135deg,#06b6d4,#8b5cf6);
    --bg-eq-hover: linear-gradient(135deg,#22d3ee,#a78bfa);
    --bg-sci: rgba(234,179,8,0.1);
    --bg-sci-hover: rgba(234,179,8,0.22);
    --bg-metric: rgba(255,255,255,0.03);
    --bg-select: rgba(255,255,255,0.06);
    --text: #f1f5f9;
    --text2: #94a3b8;
    --text3: #475569;
    --text-display: #fff;
    --text-expr: #64748b;
    --text-num: #e2e8f0;
    --text-util: #06b6d4;
    --text-op: #c4b5fd;
    --text-sci: #fbbf24;
    --cyan: #06b6d4;
    --violet: #8b5cf6;
    --amber: #f59e0b;
    --red: #ef4444;
    --green: #22c55e;
    --orange: #f97316;
    --border: rgba(255,255,255,0.04);
    --border2: rgba(255,255,255,0.06);
    --border-cyan: rgba(6,182,212,0.15);
    --shadow: 0 25px 80px rgba(0,0,0,0.5), 0 0 60px rgba(6,182,212,0.08);
    --topbar-bg: rgba(10,14,26,0.85);
    --topbar-border: rgba(6,182,212,0.08);
    --toggle-bg: rgba(255,255,255,0.1);
    --toggle-active: linear-gradient(135deg,#06b6d4,#8b5cf6);
    --slider-bg: rgba(255,255,255,0.08);
    --slider-fill: linear-gradient(90deg,#22c55e,#f59e0b,#ef4444);
}

[data-theme="light"] {
    --bg: #f0f4f8;
    --bg-calc: rgba(255,255,255,0.92);
    --bg-display: rgba(241,245,249,0.95);
    --bg-card: rgba(0,0,0,0.03);
    --bg-card-hover: rgba(0,0,0,0.06);
    --bg-btn: rgba(0,0,0,0.04);
    --bg-btn-hover: rgba(0,0,0,0.08);
    --bg-btn-active: rgba(0,0,0,0.12);
    --bg-util: rgba(6,182,212,0.1);
    --bg-util-hover: rgba(6,182,212,0.18);
    --bg-op: rgba(139,92,246,0.1);
    --bg-op-hover: rgba(139,92,246,0.2);
    --bg-eq: linear-gradient(135deg,#06b6d4,#8b5cf6);
    --bg-eq-hover: linear-gradient(135deg,#0891b2,#7c3aed);
    --bg-sci: rgba(234,179,8,0.08);
    --bg-sci-hover: rgba(234,179,8,0.18);
    --bg-metric: rgba(0,0,0,0.025);
    --bg-select: rgba(0,0,0,0.04);
    --text: #0f172a;
    --text2: #475569;
    --text3: #94a3b8;
    --text-display: #0f172a;
    --text-expr: #94a3b8;
    --text-num: #1e293b;
    --text-util: #0891b2;
    --text-op: #7c3aed;
    --text-sci: #b45309;
    --border: rgba(0,0,0,0.04);
    --border2: rgba(0,0,0,0.06);
    --border-cyan: rgba(0,0,0,0.08);
    --shadow: 0 25px 80px rgba(0,0,0,0.08);
    --topbar-bg: rgba(240,244,248,0.88);
    --topbar-border: rgba(0,0,0,0.06);
    --toggle-bg: rgba(0,0,0,0.1);
    --slider-bg: rgba(0,0,0,0.06);
}

/* ── Reset ── */
*,*::before,*::after { margin:0; padding:0; box-sizing:border-box; }
html { font-size:16px; -webkit-tap-highlight-color:transparent; }

body {
    background: var(--bg);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: background 0.4s ease;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed; inset: 0;
    background:
        radial-gradient(ellipse 600px 400px at 30% 20%, rgba(6,182,212,0.06) 0%, transparent 70%),
        radial-gradient(ellipse 500px 500px at 70% 80%, rgba(139,92,246,0.05) 0%, transparent 70%);
    z-index: -1; pointer-events: none;
}
[data-theme="light"] body::before { opacity: 0; }

/* ═══════════════════════════════════════════════════════════════════
   TOP BAR
   ═══════════════════════════════════════════════════════════════════ */
.top-bar {
    width: 100%; max-width: 860px;
    display: flex; justify-content: space-between; align-items: center;
    padding: 1rem 2rem;
    background: var(--topbar-bg);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--topbar-border);
}
.top-controls { display: flex; align-items: center; gap: 0.6rem; }

.back-link {
    display: flex; align-items: center; gap: 0.4rem;
    color: var(--text2); text-decoration: none;
    font-size: 0.85rem; font-weight: 600;
    transition: color 0.25s ease;
}
.back-link:hover { color: var(--cyan); }

.top-btn {
    width: 42px; height: 42px;
    border: 1px solid var(--border); border-radius: 12px;
    background: var(--bg-btn);
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; color: var(--text2);
    transition: all 0.25s ease;
}
.top-btn:hover { background: var(--bg-btn-hover); color: var(--cyan); }

.mode-toggle { display: flex; align-items: center; gap: 0.45rem; }
.mode-label {
    font-size: 0.8rem; font-weight: 700; color: var(--text3);
    letter-spacing: 0.5px; user-select: none; cursor: pointer;
    transition: color 0.3s ease;
}
.mode-label-active { color: var(--cyan); }

.toggle-track {
    width: 44px; height: 24px; border-radius: 100px; border: none;
    background: var(--toggle-bg); cursor: pointer; position: relative;
    transition: background 0.4s cubic-bezier(0.4,0,0.2,1);
}
.toggle-track.active { background: var(--toggle-active); }
.toggle-thumb {
    position: absolute; top: 3px; left: 3px;
    width: 18px; height: 18px; border-radius: 50%;
    background: #fff; box-shadow: 0 1px 4px rgba(0,0,0,0.25);
    transition: transform 0.35s cubic-bezier(0.34,1.56,0.64,1);
}
.toggle-track.active .toggle-thumb { transform: translateX(20px); }

.icon-moon { display: none; }
[data-theme="light"] .icon-sun { display: none; }
[data-theme="light"] .icon-moon { display: block; }

/* ═══════════════════════════════════════════════════════════════════
   CALCULATOR
   ═══════════════════════════════════════════════════════════════════ */
.calc-wrapper {
    flex: 1; display: flex; align-items: center;
    justify-content: center; padding: 2rem; width: 100%;
}

.calculator {
    width: 100%; max-width: 520px;
    background: var(--bg-calc);
    border: 1px solid var(--border-cyan);
    border-radius: 28px; padding: 1.75rem;
    box-shadow: var(--shadow);
    backdrop-filter: blur(24px);
    transition: background 0.4s ease, max-width 0.5s cubic-bezier(0.4,0,0.2,1);
    animation: calc-in 0.6s cubic-bezier(0.22,1,0.36,1);
}
.calculator.sci-mode { max-width: 860px; }

@keyframes calc-in {
    from { opacity: 0; transform: translateY(20px) scale(0.97); }
    to   { opacity: 1; transform: translateY(0) scale(1); }
}

/* ═══════════════════════════════════════════════════════════════════
   PROCESSOR DROPDOWN
   ═══════════════════════════════════════════════════════════════════ */
.proc-dropdown-wrap {
    display: flex; align-items: center; gap: 0.75rem;
    margin-bottom: 1rem;
}
.proc-label {
    font-size: 0.8rem; font-weight: 700;
    color: var(--text2); white-space: nowrap;
    flex-shrink: 0;
}
.proc-select {
    flex: 1;
    padding: 0.6rem 1rem;
    background: var(--bg-select);
    border: 1px solid var(--border2);
    border-radius: 12px;
    color: var(--text);
    font-family: 'Inter', sans-serif;
    font-size: 0.82rem;
    font-weight: 600;
    cursor: pointer;
    outline: none;
    transition: border-color 0.3s ease, background 0.3s ease;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.8rem center;
    padding-right: 2.2rem;
}
.proc-select:focus { border-color: var(--cyan); }
.proc-select option {
    background: #1a1e2e; color: var(--text);
    font-size: 0.82rem; padding: 0.5rem;
}
[data-theme="light"] .proc-select option {
    background: #fff; color: #0f172a;
}

/* ═══════════════════════════════════════════════════════════════════
   THERMAL STATS (inline, collapsible)
   ═══════════════════════════════════════════════════════════════════ */
.thermal-stats {
    background: var(--bg-card);
    border: 1px solid var(--border2);
    border-radius: 16px;
    padding: 1rem 1.1rem;
    margin-bottom: 1rem;
    animation: stats-in 0.4s cubic-bezier(0.22,1,0.36,1);
}
@keyframes stats-in {
    from { opacity: 0; transform: translateY(-8px); }
    to   { opacity: 1; transform: translateY(0); }
}
.hidden { display: none !important; }

/* Stats Header */
.stats-header {
    display: flex; align-items: center; gap: 0.65rem;
    margin-bottom: 0.75rem;
    padding-bottom: 0.65rem;
    border-bottom: 1px solid var(--border2);
}
.sh-icon { font-size: 1.6rem; }
.sh-info { flex: 1; }
.sh-name { font-size: 0.95rem; font-weight: 800; color: var(--text); }
.sh-arch {
    font-size: 0.65rem; color: var(--text3);
    font-family: 'JetBrains Mono', monospace;
}
.sh-badges { display: flex; flex-wrap: wrap; gap: 0.3rem; margin-top: 0.3rem; }
.badge {
    font-size: 0.56rem; font-weight: 700;
    padding: 0.15rem 0.4rem; border-radius: 5px;
    font-family: 'JetBrains Mono', monospace;
}
.badge-c { background: rgba(6,182,212,0.12); color: var(--cyan); }
.badge-t { background: rgba(139,92,246,0.12); color: var(--violet); }
.badge-w { background: rgba(245,158,11,0.12); color: var(--amber); }
.badge-m { background: rgba(239,68,68,0.12); color: var(--red); }

/* Load Slider */
.load-wrap {
    margin-bottom: 0.75rem;
    padding: 0.6rem 0.85rem;
    background: var(--bg-metric);
    border: 1px solid var(--border);
    border-radius: 10px;
}
.load-head {
    display: flex; justify-content: space-between;
    align-items: center; margin-bottom: 0.4rem;
}
.load-lbl { font-size: 0.7rem; font-weight: 700; color: var(--text2); }
.load-val {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.95rem; font-weight: 800; color: var(--green);
    transition: color 0.2s ease;
}
.load-range {
    width: 100%; height: 5px;
    -webkit-appearance: none; appearance: none;
    background: transparent; outline: none;
    position: relative; z-index: 2; margin: 0; cursor: pointer;
}
.load-range::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px; height: 20px; border-radius: 50%;
    border: 3px solid var(--cyan); background: var(--bg);
    cursor: pointer; box-shadow: 0 0 10px rgba(6,182,212,0.4);
}
.load-range::-moz-range-thumb {
    width: 20px; height: 20px; border-radius: 50%;
    border: 3px solid var(--cyan); background: var(--bg); cursor: pointer;
}
.load-bar {
    width: 100%; height: 5px;
    background: var(--slider-bg);
    border-radius: 100px; margin-top: -5px;
    position: relative; z-index: 1; overflow: hidden;
}
.load-fill {
    height: 100%; background: var(--slider-fill);
    border-radius: 100px; transition: width 0.1s ease;
}

/* Metrics Grid */
.metrics {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 6px;
    margin-bottom: 0.65rem;
}
.m-card {
    background: var(--bg-metric);
    border: 1px solid var(--border);
    border-radius: 10px; padding: 0.55rem 0.65rem;
    transition: border-color 0.25s ease;
}
.m-card.m-hl  { border-color: var(--cyan); }
.m-card.m-wrn { border-color: var(--amber); }
.m-card.m-dng { border-color: var(--red); }

.m-label {
    font-size: 0.5rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.7px;
    color: var(--text3); margin-bottom: 0.15rem;
}
.m-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1rem; font-weight: 800;
    color: var(--text); line-height: 1.2;
}
.m-sub { font-size: 0.52rem; color: var(--text3); margin-top: 0.1rem; }

/* Quick Use */
.quick-use-row {
    display: flex; align-items: center; gap: 0.5rem;
    flex-wrap: wrap;
}
.qu-label {
    font-size: 0.6rem; font-weight: 600; color: var(--text3);
    white-space: nowrap;
}
.quick-btns { display: flex; flex-wrap: wrap; gap: 4px; flex: 1; }
.q-btn {
    display: inline-flex; align-items: center; gap: 0.25rem;
    padding: 0.3rem 0.55rem;
    background: var(--bg-btn); border: 1px solid var(--border2);
    border-radius: 7px; color: var(--text);
    font-family: 'Inter', sans-serif; font-size: 0.62rem; font-weight: 600;
    cursor: pointer; transition: all 0.2s ease;
}
.q-btn:hover { background: var(--cyan); color: #fff; border-color: var(--cyan); }
.q-btn .q-lbl { color: var(--text3); font-size: 0.55rem; }
.q-btn:hover .q-lbl { color: rgba(255,255,255,0.7); }
.q-btn .q-val { font-family: 'JetBrains Mono', monospace; font-weight: 700; }

/* ═══════════════════════════════════════════════════════════════════
   DISPLAY
   ═══════════════════════════════════════════════════════════════════ */
.display-area {
    background: var(--bg-display);
    border-radius: 18px; padding: 2rem 1.75rem 1.5rem;
    margin-bottom: 1.25rem; min-height: 130px;
    display: flex; flex-direction: column;
    justify-content: flex-end; align-items: flex-end;
    border: 1px solid var(--border);
    transition: background 0.4s ease;
}
.expression {
    width: 100%; text-align: right;
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.05rem; color: var(--text-expr);
    min-height: 1.5rem; word-break: break-all;
    margin-bottom: 0.5rem;
}
.display {
    width: 100%; text-align: right;
    font-family: 'JetBrains Mono', monospace;
    font-size: 3.4rem; font-weight: 700;
    color: var(--text-display); line-height: 1.15;
    word-break: break-all; min-height: 3.8rem;
    transition: font-size 0.2s ease;
}
.display.shrink-sm { font-size: 2.6rem; }
.display.shrink-md { font-size: 2rem; }
.display.shrink-lg { font-size: 1.5rem; }

/* ═══════════════════════════════════════════════════════════════════
   BUTTONS
   ═══════════════════════════════════════════════════════════════════ */
.btn-body { display: flex; gap: 14px; }

.sci-panel {
    display: grid; grid-template-columns: repeat(2,1fr);
    grid-template-rows: repeat(6,1fr); gap: 6px;
    width: 0; opacity: 0; overflow: hidden;
    transition: width 0.45s cubic-bezier(0.4,0,0.2,1), opacity 0.35s ease;
}
.sci-panel.visible { width: 200px; opacity: 1; }

.btn-sci {
    background: var(--bg-sci); color: var(--text-sci);
    font-size: 1rem; font-weight: 700;
    font-family: 'JetBrains Mono', monospace;
    aspect-ratio: auto; padding: 0.75rem 0.5rem;
    min-height: 0; border-radius: 14px;
}
.btn-sci:hover { background: var(--bg-sci-hover); transform: translateY(-1px); }
.btn-sci:active { transform: scale(0.95); }

.btn-grid {
    display: grid; grid-template-columns: repeat(4,1fr);
    gap: 12px; flex: 1;
}

.btn {
    aspect-ratio: 1/1;
    border: 1px solid var(--border); border-radius: 18px;
    font-family: 'Inter', sans-serif; font-size: 1.6rem; font-weight: 600;
    cursor: pointer; display: flex;
    align-items: center; justify-content: center;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
    transition: all 0.2s cubic-bezier(0.4,0,0.2,1);
    user-select: none; position: relative; overflow: hidden;
}
.btn::after {
    content: ''; position: absolute; inset: 0; border-radius: inherit;
    background: radial-gradient(circle at var(--ripple-x,50%) var(--ripple-y,50%),
        rgba(255,255,255,0.25) 0%, transparent 60%);
    opacity: 0; transition: opacity 0.4s ease; pointer-events: none;
}
.btn.ripple::after { opacity: 1; }

.btn-number { background: var(--bg-btn); color: var(--text-num); }
.btn-number:hover { background: var(--bg-btn-hover); transform: translateY(-1px); }
.btn-number:active { background: var(--bg-btn-active); transform: scale(0.95); }

.btn-util { background: var(--bg-util); color: var(--text-util); font-weight: 700; }
.btn-util:hover { background: var(--bg-util-hover); transform: translateY(-1px); }
.btn-util:active { transform: scale(0.95); }

.btn-operator { background: var(--bg-op); color: var(--text-op); font-weight: 700; }
.btn-operator:hover { background: var(--bg-op-hover); transform: translateY(-1px); }
.btn-operator:active { transform: scale(0.95); }
.btn-operator.active-op {
    background: var(--violet); color: #fff;
    box-shadow: 0 0 20px rgba(139,92,246,0.4);
}

.btn-equals {
    background: var(--bg-eq); color: #fff;
    font-size: 1.9rem; font-weight: 800;
    box-shadow: 0 4px 20px rgba(6,182,212,0.3);
}
.btn-equals:hover { background: var(--bg-eq-hover); transform: translateY(-2px); box-shadow: 0 6px 28px rgba(6,182,212,0.4); }
.btn-equals:active { transform: scale(0.95); }

/* ═══════════════════════════════════════════════════════════════════
   HISTORY OVERLAY
   ═══════════════════════════════════════════════════════════════════ */
.history-overlay {
    position: fixed; inset: 0; z-index: 100;
    background: var(--bg);
    display: flex; justify-content: center;
    transform: translateX(100%); opacity: 0;
    transition: transform 0.4s cubic-bezier(0.32,0.72,0,1), opacity 0.3s ease;
    pointer-events: none;
}
.history-overlay.open { transform: translateX(0); opacity: 1; pointer-events: auto; }

.history-inner { width: 100%; max-width: 500px; display: flex; flex-direction: column; }
.history-head {
    display: flex; justify-content: space-between; align-items: center;
    padding: 1rem 1.5rem; border-bottom: 1px solid var(--border2);
}
.history-head h2 { font-size: 1.05rem; font-weight: 700; color: var(--text); }

.overlay-back {
    display: flex; align-items: center; gap: 0.3rem;
    background: none; border: none; color: var(--cyan);
    font-family: 'Inter', sans-serif; font-size: 0.85rem; font-weight: 600;
    cursor: pointer; padding: 0.4rem 0.5rem; border-radius: 8px;
}
.overlay-back:hover { background: var(--bg-btn-hover); }

.hist-clear {
    background: none; border: 1px solid rgba(239,68,68,0.3);
    color: var(--red); padding: 0.3rem 0.75rem;
    border-radius: 8px; font-size: 0.72rem; font-weight: 600;
    cursor: pointer; font-family: 'Inter', sans-serif;
}
.hist-clear:hover { background: rgba(239,68,68,0.1); }

.history-body { flex: 1; overflow-y: auto; padding: 0.5rem 1.5rem 2rem; }
.hist-list { list-style: none; }
.hist-item {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0.9rem 0.75rem; border-bottom: 1px solid var(--border2);
    cursor: pointer; border-radius: 10px; gap: 1rem;
    transition: background 0.2s ease;
}
.hist-item:hover { background: var(--bg-btn-hover); }
.hist-expr { font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; color: var(--text2); }
.hist-result {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.15rem; font-weight: 700; color: var(--cyan); flex-shrink: 0;
}
.hist-empty {
    display: flex; flex-direction: column; align-items: center;
    gap: 0.5rem; margin-top: 4rem; color: var(--text3);
}
.hist-empty p { font-size: 0.9rem; font-weight: 600; color: var(--text2); }
.hist-empty.hidden { display: none; }

/* ═══════════════════════════════════════════════════════════════════
   SHAKE
   ═══════════════════════════════════════════════════════════════════ */
.display-area.shake { animation: shake 0.4s cubic-bezier(0.36,0.07,0.19,0.97); }
@keyframes shake {
    0%,100% { transform: translateX(0); }
    10%,30%,50%,70%,90% { transform: translateX(-4px); }
    20%,40%,60%,80% { transform: translateX(4px); }
}

/* ═══════════════════════════════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════════════════════════════ */
@media (max-width: 640px) {
    .top-bar { max-width: 100%; padding: 0.7rem 1rem; }
    .calculator { max-width: 100%; padding: 1.25rem; border-radius: 20px; }
    .calculator.sci-mode { max-width: 100%; }
    .btn-body { flex-direction: column; }
    .sci-panel.visible {
        width: 100%; grid-template-columns: repeat(4,1fr);
        grid-template-rows: repeat(3,1fr);
    }
    .display { font-size: 2.6rem; }
    .display-area { min-height: 100px; padding: 1.25rem 1rem 1rem; }
    .btn { font-size: 1.3rem; border-radius: 14px; }
    .btn-sci { font-size: 0.85rem; padding: 0.55rem 0.2rem; }
    .btn-grid { gap: 8px; }
    .metrics { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 400px) {
    .top-bar { padding: 0.6rem 0.75rem; }
    .calculator { padding: 0.85rem; }
    .btn-grid { gap: 6px; }
    .btn { border-radius: 12px; font-size: 1.1rem; }
    .display { font-size: 2.2rem; }
    .btn-sci { font-size: 0.72rem; }
    .proc-dropdown-wrap { flex-direction: column; gap: 0.3rem; }
}

@media (min-width: 1024px) {
    .calc-wrapper { padding: 3rem; }
    .top-bar { max-width: 900px; }
}

/* ── Focus ──*/
.btn:focus-visible, .top-btn:focus-visible, .toggle-track:focus-visible {
    outline: 2px solid var(--cyan); outline-offset: 2px;
}