/* ============================================
   Gas Mileage Calculator Pro — Stylesheet
   Clean, automotive, professional UI
   ============================================ */
@import url('https://fonts.googleapis.com/css2?family=Barlow:wght@400;500;600;700&family=Barlow+Condensed:wght@600;700&family=IBM+Plex+Mono:wght@500;600&display=swap');

:root {
    --gmc-blue:       #1d4ed8;
    --gmc-blue-dark:  #1e3a8a;
    --gmc-blue-light: #eff6ff;
    --gmc-green:      #16a34a;
    --gmc-green-lt:   #f0fdf4;
    --gmc-orange:     #ea580c;
    --gmc-orange-lt:  #fff7ed;
    --gmc-yellow:     #ca8a04;
    --gmc-text:       #0f172a;
    --gmc-muted:      #64748b;
    --gmc-border:     #e2e8f0;
    --gmc-card:       #ffffff;
    --gmc-bg:         #f8fafc;
    --gmc-radius:     14px;
    --gmc-shadow:     0 4px 24px rgba(0,0,0,0.08), 0 1px 4px rgba(0,0,0,0.04);
    --gmc-display:    'Barlow Condensed', sans-serif;
    --gmc-body:       'Barlow', sans-serif;
    --gmc-mono:       'IBM Plex Mono', monospace;
}

.gmc-wrap {
    font-family: var(--gmc-body);
    color: var(--gmc-text);
    max-width: 680px;
    margin: 0 auto;
}

.gmc-card {
    background: var(--gmc-card);
    border-radius: var(--gmc-radius);
    box-shadow: var(--gmc-shadow);
    overflow: hidden;
    border: 1px solid var(--gmc-border);
}

/* ---- HEADER ---- */
.gmc-header {
    background: linear-gradient(135deg, #0f172a 0%, #1d4ed8 100%);
    padding: 26px 28px 22px;
    display: flex;
    align-items: center;
    gap: 16px;
}
.gmc-header-icon {
    font-size: 2.4rem;
    line-height: 1;
    filter: drop-shadow(0 2px 8px rgba(0,0,0,0.3));
}
.gmc-header-text h2 {
    font-family: var(--gmc-display);
    font-size: 1.75rem;
    font-weight: 700;
    color: white;
    margin: 0 0 2px;
    padding: 0;
    border: none;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}
.gmc-header-text p {
    font-size: 0.83rem;
    color: rgba(255,255,255,0.65);
    margin: 0;
}

/* ---- UNIT TOGGLE ---- */
.gmc-unit-bar {
    background: #0f172a;
    padding: 10px 28px;
    display: flex;
    align-items: center;
    gap: 12px;
}
.gmc-unit-label {
    font-size: 0.78rem;
    font-weight: 600;
    color: rgba(255,255,255,0.5);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.gmc-unit-toggle {
    display: flex;
    background: rgba(255,255,255,0.1);
    border-radius: 8px;
    padding: 3px;
    gap: 3px;
}
.gmc-unit-btn {
    font-family: var(--gmc-body);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 5px 14px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    color: rgba(255,255,255,0.6);
    background: transparent;
    transition: all 0.2s;
    letter-spacing: 0.3px;
}
.gmc-unit-btn.active {
    background: var(--gmc-blue);
    color: white;
    box-shadow: 0 2px 8px rgba(29,78,216,0.4);
}

/* ---- TABS ---- */
.gmc-tabs {
    display: flex;
    border-bottom: 2px solid var(--gmc-border);
    background: var(--gmc-bg);
}
.gmc-tab {
    font-family: var(--gmc-body);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 13px 20px;
    border: none;
    background: transparent;
    color: var(--gmc-muted);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 6px;
    white-space: nowrap;
}
.gmc-tab:hover { color: var(--gmc-blue); }
.gmc-tab.active {
    color: var(--gmc-blue);
    border-bottom-color: var(--gmc-blue);
    background: white;
}

/* ---- TAB PANELS ---- */
.gmc-panel { display: none; padding: 24px 28px; }
.gmc-panel.active { display: block; }

/* ---- FORM GRID ---- */
.gmc-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 20px;
}
.gmc-grid-3 { grid-template-columns: 1fr 1fr 1fr; }
.gmc-full { grid-column: 1 / -1; }

.gmc-field {
    display: flex;
    flex-direction: column;
    gap: 5px;
}
.gmc-field label {
    font-size: 0.78rem;
    font-weight: 700;
    color: var(--gmc-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.gmc-field label span {
    font-weight: 400;
    text-transform: none;
    font-size: 0.75rem;
}

/* ---- INPUTS ---- */
.gmc-input-wrap {
    position: relative;
    display: flex;
    align-items: center;
}
.gmc-input {
    font-family: var(--gmc-mono);
    font-size: 1rem;
    font-weight: 500;
    width: 100%;
    border: 1.5px solid var(--gmc-border);
    border-radius: 9px;
    padding: 10px 14px;
    background: var(--gmc-bg);
    color: var(--gmc-text);
    box-sizing: border-box;
    transition: all 0.18s;
    outline: none;
    -moz-appearance: textfield;
}
.gmc-input::-webkit-outer-spin-button,
.gmc-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.gmc-input:focus {
    border-color: var(--gmc-blue);
    background: white;
    box-shadow: 0 0 0 3px rgba(29,78,216,0.1);
}
.gmc-input-suffix {
    position: absolute;
    right: 12px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--gmc-muted);
    pointer-events: none;
}

/* ---- DIVIDER ---- */
.gmc-or {
    text-align: center;
    font-size: 0.78rem;
    font-weight: 700;
    color: var(--gmc-muted);
    letter-spacing: 1px;
    text-transform: uppercase;
    position: relative;
    margin: 4px 0;
}
.gmc-or::before, .gmc-or::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 38%;
    height: 1px;
    background: var(--gmc-border);
}
.gmc-or::before { left: 0; }
.gmc-or::after  { right: 0; }

/* ---- BUTTON ---- */
.gmc-btn {
    font-family: var(--gmc-body);
    font-size: 0.95rem;
    font-weight: 700;
    padding: 12px 28px;
    border: none;
    border-radius: 9px;
    cursor: pointer;
    background: linear-gradient(135deg, var(--gmc-blue), var(--gmc-blue-dark));
    color: white;
    transition: all 0.18s;
    box-shadow: 0 3px 14px rgba(29,78,216,0.28);
    letter-spacing: 0.2px;
    display: inline-flex;
    align-items: center;
    gap: 7px;
}
.gmc-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(29,78,216,0.35);
}
.gmc-btn-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    align-items: center;
}
.gmc-btn-clear {
    background: white;
    color: var(--gmc-muted);
    border: 1.5px solid var(--gmc-border);
    box-shadow: none;
    font-size: 0.85rem;
    padding: 10px 18px;
}
.gmc-btn-clear:hover { background: var(--gmc-bg); transform: none; box-shadow: none; }

/* ---- RESULTS ---- */
.gmc-results {
    display: none;
    margin-top: 20px;
    border-top: 1.5px solid var(--gmc-border);
    padding-top: 20px;
    animation: gmc-fade-in 0.4s ease both;
}
@keyframes gmc-fade-in {
    from { opacity: 0; transform: translateY(10px); }
    to   { opacity: 1; transform: translateY(0); }
}
.gmc-results-title {
    font-family: var(--gmc-display);
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--gmc-muted);
    margin-bottom: 14px;
}

/* ---- RESULT CARDS ---- */
.gmc-result-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 12px;
    margin-bottom: 16px;
}
.gmc-result-card {
    border-radius: 10px;
    padding: 14px 16px;
    border: 1.5px solid var(--gmc-border);
    background: var(--gmc-bg);
}
.gmc-result-card.primary {
    background: var(--gmc-blue-light);
    border-color: #bfdbfe;
}
.gmc-result-card.green {
    background: var(--gmc-green-lt);
    border-color: #bbf7d0;
}
.gmc-result-card.orange {
    background: var(--gmc-orange-lt);
    border-color: #fed7aa;
}
.gmc-result-label {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--gmc-muted);
    margin-bottom: 5px;
}
.gmc-result-value {
    font-family: var(--gmc-mono);
    font-size: 1.55rem;
    font-weight: 600;
    color: var(--gmc-text);
    line-height: 1;
}
.gmc-result-card.primary .gmc-result-value { color: var(--gmc-blue); }
.gmc-result-card.green   .gmc-result-value { color: var(--gmc-green); }
.gmc-result-card.orange  .gmc-result-value { color: var(--gmc-orange); }
.gmc-result-unit {
    font-size: 0.75rem;
    color: var(--gmc-muted);
    margin-top: 3px;
}

/* ---- EFFICIENCY RATING BAR ---- */
.gmc-efficiency-bar-wrap {
    background: var(--gmc-bg);
    border: 1.5px solid var(--gmc-border);
    border-radius: 10px;
    padding: 14px 16px;
    margin-bottom: 12px;
}
.gmc-eff-label-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    margin-bottom: 8px;
}
.gmc-eff-label { font-weight: 700; color: var(--gmc-muted); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.5px; }
.gmc-eff-rating { font-weight: 700; font-size: 0.9rem; }
.gmc-eff-bar-bg {
    height: 10px;
    background: #e2e8f0;
    border-radius: 99px;
    overflow: hidden;
}
.gmc-eff-bar-fill {
    height: 100%;
    border-radius: 99px;
    transition: width 0.8s cubic-bezier(0.22,1,0.36,1);
    background: linear-gradient(90deg, #ef4444, #f59e0b, #22c55e);
    width: 0%;
}

/* ---- TIPS ---- */
.gmc-tip-box {
    background: #f0f9ff;
    border: 1.5px solid #bae6fd;
    border-radius: 10px;
    padding: 12px 16px;
    font-size: 0.83rem;
    color: #0369a1;
    line-height: 1.6;
}
.gmc-tip-box strong { color: #075985; }

/* ---- SECTION LABEL ---- */
.gmc-section-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--gmc-blue);
    border-bottom: 1.5px solid var(--gmc-blue-light);
    padding-bottom: 6px;
    margin-bottom: 14px;
    margin-top: 8px;
}

/* ---- RESPONSIVE ---- */
@media (max-width: 520px) {
    .gmc-header { padding: 20px 18px; }
    .gmc-panel  { padding: 18px 16px; }
    .gmc-unit-bar { padding: 10px 16px; }
    .gmc-grid   { grid-template-columns: 1fr; }
    .gmc-grid-3 { grid-template-columns: 1fr 1fr; }
    .gmc-tab    { padding: 11px 12px; font-size: 0.78rem; }
    .gmc-result-value { font-size: 1.25rem; }
}

/* ---- PRINT ---- */
@media print {
    .gmc-tabs, .gmc-btn-row, .gmc-unit-bar { display: none !important; }
    .gmc-panel { display: block !important; }
    .gmc-results { display: block !important; }
    .gmc-card { box-shadow: none; border: 1px solid #ccc; }
}