/* ========================================
   Professional Calculator Styles
   iXDataWave - Wireless Communication Tools
   ======================================== */

.calc-page-section {
    padding-top: 100px;
    padding-bottom: 60px;
    min-height: calc(100vh - 300px);
    background: linear-gradient(180deg, #f0f4f8 0%, #fff 100%);
}

/* Calculator Container */
.calc-box {
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 8px 40px rgba(0,0,0,0.08), 0 2px 10px rgba(0,0,0,0.04);
    overflow: hidden;
    margin-top: 30px;
}

/* Tab Menu */
#calc-menu {
    background: linear-gradient(135deg, #1a2332 0%, #2c3e50 50%, #34495e 100%);
    padding: 0;
    position: relative;
    overflow: hidden;
}

#calc-menu::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 200%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.05), transparent);
    animation: shimmer 4s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-50%); }
    100% { transform: translateX(50%); }
}

#calc-menu ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
    z-index: 1;
}

#calc-menu ul li {
    flex: 1;
}

#calc-menu ul li a {
    display: block;
    padding: 18px 24px;
    color: rgba(255,255,255,0.65);
    text-decoration: none;
    font-size: 14.5px;
    font-weight: 500;
    text-align: center;
    transition: all 0.35s cubic-bezier(.25,.46,.45,.94);
    border-bottom: 3px solid transparent;
    letter-spacing: 0.3px;
    position: relative;
}

#calc-menu ul li a::before {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 40px;
    height: 3px;
    background: linear-gradient(90deg, #4facfe, #00f2fe);
    border-radius: 3px;
    transition: transform 0.35s cubic-bezier(.25,.46,.45,.94);
}

#calc-menu ul li a:hover {
    color: #fff;
    background: rgba(255,255,255,0.08);
}

#calc-menu ul li a:hover::before,
#calc-menu ul li.nav-active a::before {
    transform: translateX(-50%) scaleX(1);
}

#calc-menu ul li.nav-active a,
#calc-menu ul li a.active {
    color: #fff;
    background: linear-gradient(135deg, #f97316 0%, #ea580c 100%);
    border-bottom-color: #c2410c;
}

/* Panel Content */
.calc-panel {
    padding: 36px;
    display: none;
}

.calc-panel-show {
    display: block;
    animation: panelIn 0.4s cubic-bezier(.25,.46,.45,.94);
}

.calc-panel-hide {
    display: none;
}

@keyframes panelIn {
    from { opacity: 0; transform: translateY(16px) scale(0.98); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

/* ========== Fresnel Zone Panel - Vertical Linear Layout ========== */
.fresnel-vertical {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Output / Result Display - 横向排布 */
.fresnel-vertical .calc-output {
    background: linear-gradient(135deg, #ecf6ff 0%, #e8f4fd 100%);
    border-radius: 12px;
    padding: 24px 28px;
    border-left: 4px solid #4facfe;
    position: relative;
    overflow: hidden;
}

.fresnel-vertical .calc-output .result-box {
    display: flex;
    gap: 40px;
    position: relative;
}

.fresnel-vertical .calc-output .result-box p {
    margin: 0;
}

/* Image Box */
.calc-img-box {
    background: linear-gradient(145deg, #f8fbff, #eef3fa);
    border-radius: 12px;
    padding: 22px;
    text-align: center;
    border: 1px solid rgba(79,172,254,0.12);
    position: relative;
    overflow: hidden;
}

.calc-img-box::before {
    content: '';
    position: absolute;
    top: -40px;
    right: -40px;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(79,172,254,0.08), transparent 70%);
    border-radius: 50%;
}

/* Fresnel Zone 独立标题 */
.fresnel-title {
    color: #1a2332;
    font-size: 20px;
    font-weight: 700;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 10px;
    padding-bottom: 12px;
    border-bottom: 2px solid #f1f5f9;
    position: relative;
}

.fresnel-title::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 50px;
    height: 2px;
    background: linear-gradient(90deg, #f97316, #fb923c);
    border-radius: 1px;
}

.calc-img-box img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.1);
}

/* Output / Result Display - 通用样式 */
.calc-output::after {
    content: '';
    position: absolute;
    top: -20px;
    right: -20px;
    width: 80px;
    height: 80px;
    background: radial-gradient(circle, rgba(79,172,254,0.12), transparent 70%);
    border-radius: 50%;
}

.result-box p {
    margin: 10px 0;
    font-size: 14.5px;
    color: #334155;
    display: flex;
    align-items: baseline;
    gap: 6px;
    position: relative;
}

.result-box p span:first-child {
    font-size: 26px;
    font-weight: 700;
    color: #4facfe;
    min-width: 80px;
    font-variant-numeric: tabular-nums;
    letter-spacing: -0.5px;
}

.result-box .unit {
    color: #64748b;
    font-weight: 500;
    font-size: 13px;
}

/* Input Section - 横向排布 */
.fresnel-vertical .calc-input {
    background: #fafbfc;
    border-radius: 12px;
    padding: 26px 28px;
    border: 1px solid #e8ecf0;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px 40px;
    align-items: start;
}

.fresnel-vertical .calc-input .input-row {
    margin-bottom: 0;
}

.input-row {
    display: flex;
    align-items: center;
    margin-bottom: 18px;
}

.input-row:last-of-type {
    margin-bottom: 0;
}

.input-row label {
    min-width: 140px;
    font-weight: 600;
    color: #374151;
    font-size: 13.5px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.input-row input {
    flex: 1;
    min-width: 160px;
    max-width: 260px;
    padding: 11px 16px;
    border: 1.5px solid #d1d9e0;
    border-radius: 8px;
    font-size: 14.5px;
    transition: all 0.25s ease;
    outline: none;
    background: #fff;
    color: #1a2332;
    font-family: inherit;
}

.input-row input:focus {
    border-color: #4facfe;
    box-shadow: 0 0 0 4px rgba(79,172,254,0.1), 0 2px 8px rgba(79,172,254,0.06);
    background: #fff;
}

.input-row input::placeholder {
    color: #b0bac7;
}

.input-unit {
    margin-left: 12px;
    color: #64748b;
    font-size: 13px;
    font-weight: 500;
    min-width: 55px;
    background: #eef2f7;
    padding: 6px 11px;
    border-radius: 6px;
    white-space: nowrap;
}

/* Buttons */
.btn-calc-wrapper {
    display: flex;
    justify-content: center;
    margin-top: 22px;
}

.btn-calc {
    padding: 13px 42px;
    border: none;
    border-radius: 10px;
    font-size: 14.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(.25,.46,.45,.94);
    outline: none;
    letter-spacing: 0.3px;
    position: relative;
    overflow: hidden;
}

.btn-calc::before {
    content: '';
    position: absolute;
    top: 0; left: -100%; width: 100%; height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
}

.btn-calc:hover::before { left: 100%; }

.btn-primary {
    background: linear-gradient(135deg, #4facfe 0%, #00b4db 100%);
    color: #fff;
    box-shadow: 0 4px 14px rgba(79,172,254,0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 22px rgba(79,172,254,0.45);
}

.btn-success {
    background: linear-gradient(135deg, #38c172 0%, #27ae60 100%);
    color: #fff;
    box-shadow: 0 4px 14px rgba(56,193,114,0.35);
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 22px rgba(56,193,114,0.45);
}

.btn-danger {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a5a 100%);
    color: #fff;
    box-shadow: 0 4px 14px rgba(255,107,107,0.35);
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 22px rgba(255,107,107,0.45);
}

/* ========== Link Budget Grid Output ========== */
.calc-output-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
    margin-bottom: 28px;
}

.result-box-grid {
    background: linear-gradient(145deg, #f0fdf4 0%, #ecfdf5 100%);
    border-radius: 12px;
    padding: 22px 18px;
    text-align: center;
    border-top: 3px solid #38c172;
    transition: transform 0.25s ease;
}

.result-box-grid:hover {
    transform: translateY(-3px);
}

.result-box-grid p {
    margin: 0;
    font-size: 13px;
    color: #475569;
    line-height: 1.5;
}

.result-box-grid p span:first-child {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: #16a34a;
    margin-bottom: 8px;
    font-variant-numeric: tabular-nums;
    letter-spacing: -0.5px;
}

.grid-input {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px 28px;
}

.grid-input .input-row {
    margin-bottom: 0;
}

.btn-row {
    grid-column: 1 / -1;
    text-align: center;
    margin-top: 8px;
}

.panel-title {
    color: #1a2332;
    font-size: 21px;
    font-weight: 700;
    margin-bottom: 24px;
    padding-bottom: 14px;
    border-bottom: 2px solid #f1f5f9;
    position: relative;
}

.panel-title::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 60px;
    height: 2px;
    background: linear-gradient(90deg, #4facfe, #38c172);
    border-radius: 1px;
}

/* ========== dBm Conversion Layout ========== */
.conversion-input {
    max-width: 650px;
    margin: 0 auto;
}

.conversion-cards {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.conversion-card {
    background: linear-gradient(145deg, #ffffff, #f8fafc);
    border: 1.5px solid #e2e8f0;
    border-radius: 12px;
    padding: 22px 26px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.conversion-card .input-row {
    margin-bottom: 0;
    flex-direction: column;
    align-items: stretch;
}

.conversion-card .input-row input {
    width: 100%;
    max-width: 100%;
    min-height: 48px;
    text-align: center;
    font-size: 18px;
    font-weight: 600;
    padding: 14px 20px;
    letter-spacing: 0.5px;
    box-sizing: border-box;
}

.conversion-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(180deg, #4facfe, #00f2fe);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.conversion-card:hover {
    border-color: #4facfe;
    box-shadow: 0 4px 16px rgba(79,172,254,0.1);
}

.conversion-card:hover::before { opacity: 1; }

.conversion-card .input-unit {
    display: block;
    text-align: center;
    margin-left: 0;
    margin-top: 8px;
    font-size: 12.5px;
    background: transparent;
    padding: 0;
    border-radius: 0;
    color: #64748b;
    letter-spacing: 0.5px;
}

.btn-group {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-top: 28px;
}

/* ========== Description Section ========== */
.calc-description {
    margin-top: 32px;
    padding-top: 28px;
    border-top: 2px dashed #e8ecf0;
}

.calc-description h3 {
    color: #1a2332;
    font-size: 16px;
    font-weight: 700;
    margin: 22px 0 12px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.calc-description h3:first-child { margin-top: 0; }

.calc-description h3::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 18px;
    background: linear-gradient(180deg, #4facfe, #38c172);
    border-radius: 2px;
}

.calc-description p {
    color: #475569;
    line-height: 1.85;
    font-size: 14px;
    margin-bottom: 14px;
    text-align: justify;
}

.desc-img-box {
    display: flex;
    gap: 16px;
    margin: 20px 0;
    flex-wrap: wrap;
}

.desc-img-box img {
    max-width: 48%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    border: 1px solid #eee;
    transition: transform 0.3s ease;
}

.desc-img-box img:hover {
    transform: scale(1.02);
}

/* ========================================
   Dropdown Navigation Styles (local override)
   ======================================== */

.nav-item.has-dropdown {
    position: relative;
}

.nav-item.has-dropdown > .nav-link::after {
    content: '\25BC';
    font-size: 10px;
    margin-left: 5px;
    transition: transform 0.3s ease;
}

.nav-item.has-dropdown:hover > .nav-link::after {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: #fff;
    list-style: none;
    min-width: 210px;
    box-shadow: 0 12px 35px rgba(0,0,0,0.12), 0 2px 8px rgba(0,0,0,0.06);
    border-radius: 0 0 12px 12px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.3s cubic-bezier(.25,.46,.45,.94);
    z-index: 1001;
    padding: 8px 0;
    margin: 0;
    backdrop-filter: blur(10px);
}

.nav-item.has-dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li { margin: 0; }

.dropdown-menu li a {
    display: block;
    padding: 11px 22px;
    color: #475569;
    text-decoration: none;
    font-size: 13.5px;
    font-weight: 400;
    transition: all 0.2s ease;
}

.dropdown-menu li a:hover,
.dropdown-menu li a.dropdown-active {
    background: linear-gradient(90deg, rgba(79,172,254,0.08), transparent);
    color: #4facfe;
    padding-left: 26px;
}

/* ========================================
   Responsive Design
   ======================================== */

@media screen and (max-width: 992px) {
    .calc-output-grid {
        grid-template-columns: 1fr;
    }

    .grid-input {
        grid-template-columns: 1fr;
    }

    .btn-group {
        flex-direction: column;
    }

    .btn-calc {
        width: 100%;
    }

    .desc-img-box img {
        max-width: 100%;
    }
}

@media screen and (max-width: 768px) {
    .calc-page-section {
        padding-top: 80px;
        background: #fff;
    }

    .calc-panel { padding: 22px 16px; }

    /* Mobile Tabs */
    #calc-menu ul {
        flex-direction: column;
    }

    #calc-menu ul li a {
        padding: 13px 18px;
        font-size: 14px;
        border-bottom: 1px solid rgba(255,255,255,0.08);
        border-right: 3px solid transparent;
        text-align: left;
        border-bottom-color: transparent;
    }

    #calc-menu ul li a::before {
        display: none;
    }

    #calc-menu ul li.nav-active a,
    #calc-menu ul li a.active {
        border-right-color: #f97316;
        background: linear-gradient(135deg, rgba(249,115,22,0.85) 0%, rgba(234,88,12,0.9) 100%);
    }

    #calc-menu ul li + li a { border-top: 1px solid rgba(255,255,255,0.06); }

    /* Mobile Inputs */
    .input-row {
        flex-direction: column;
        align-items: stretch;
    }

    .input-row label {
        min-width: 100%;
        margin-bottom: 6px;
    }

    .input-row input {
        max-width: 100%;
    }

    .input-unit {
        align-self: flex-start;
        margin-top: 6px;
        margin-left: 0;
    }

    /* Fresnel vertical layout - stack on mobile */
    .fresnel-vertical {
        gap: 18px;
    }

    .calc-img-box,
    .fresnel-vertical .calc-output {
        min-width: 100%;
    }

    .fresnel-vertical .calc-output .result-box {
        flex-direction: column;
        gap: 14px;
    }

    .fresnel-vertical .calc-input {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    /* Mobile dropdown */
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        background: rgba(79,172,254,0.05);
        border-radius: 0;
        padding: 0 0 0 16px;
        display: none;
    }

    .nav-item.has-dropdown.active .dropdown-menu { display: block; }

    .dropdown-menu li a {
        padding: 11px 14px;
        font-size: 13px;
    }

    .result-box p span:first-child { font-size: 22px; }
    .result-box-grid p span:first-child { font-size: 24px; }
}

@media screen and (max-width: 480px) {
    .calc-panel { padding: 16px 12px; }

    .fresnel-title,
    .panel-title {
        font-size: 16px;
    }

    .calc-input { padding: 18px 16px; }

    .btn-calc { padding: 12px 28px; font-size: 14px; }

    .result-box-grid { padding: 16px 12px; }

    .conversion-card { padding: 18px 16px; }
}