/* 计算器独有样式 */
.calc-container {
    max-width: 680px;
    margin: 120px auto 80px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 3rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

.calc-container h2 {
    text-align: center;
    margin-bottom: 2.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 2.2rem;
    font-weight: 700;
}

.mode-toggle {
    display: flex;
    background: rgba(0, 0, 0, 0.05);
    border-radius: 15px;
    padding: 6px;
    margin: 25px auto;
    max-width: 400px;
    border: 1px solid var(--border-color);
}

.mode-btn {
    flex: 1;
    padding: 12px;
    text-align: center;
    font-weight: 600;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    color: var(--text-gray);
    position: relative;
    z-index: 2;
}

.mode-btn.active {
    background: white;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    color: #2c3e50;
    transform: translateY(-2px);
}

.form-group {
    margin-bottom: 1.8rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.8rem;
    color: var(--text-gray);
    font-weight: 500;
    font-size: 1.1rem;
}

.input-container {
    display: flex;
    align-items: center;
    border: 2px solid var(--border-color);
    background: var(--dark-bg);
    color: var(--text-light);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s ease;
}

.input-container:focus-within {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(0, 198, 255, 0.2);
}

.input-container i {
    padding: 0 18px;
    color: var(--accent-color);
    font-size: 20px;
}

.form-group input {
    flex: 1;
    border: none;
    padding: 1rem;
    font-size: 1.1rem;
    outline: none;
    background: transparent;
    color: var(--text-light);
    font-weight: 500;
}

.preset-taxes {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 25px;
}

.tax-btn {
    padding: 14px;
    background: rgba(0, 198, 255, 0.1);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    text-align: center;
    font-weight: 600;
    color: var(--accent-color);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 16px;
}

.tax-btn:hover {
    background: rgba(0, 198, 255, 0.2);
    transform: translateY(-3px);
}

.tax-btn.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
    transform: scale(0.97);
    box-shadow: 0 5px 15px rgba(0, 198, 255, 0.3);
}

.btn-block {
    width: 100%;
    margin-top: 1.5rem;
    padding: 1.2rem;
    font-size: 1.2rem;
    font-weight: 600;
    letter-spacing: 1px;
    border-radius: 12px;
    background: linear-gradient(135deg, var(--accent-color), #00a8e8);
    box-shadow: 0 8px 25px rgba(0, 198, 255, 0.4);
    transition: all 0.4s ease;
    display: block;
}

.btn-block:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(0, 198, 255, 0.5);
}

.result-box {
    margin-top: 2.5rem;
    padding: 1.8rem;
    background: linear-gradient(135deg, rgba(0, 198, 255, 0.08), rgba(0, 198, 255, 0.03));
    border-left: 4px solid var(--accent-color);
    border-radius: 12px;
    display: none;
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.result-box p {
    margin: 0.8rem 0;
    color: var(--text-light);
    font-size: 1.1rem;
    display: flex;
    justify-content: space-between;
}

.result-box strong {
    color: var(--accent-color);
    font-size: 1.3rem;
    font-weight: 700;
}

.history {
    margin-top: 25px;
    max-height: 200px;
    overflow-y: auto;
    border: 2px solid var(--border-color);
    border-radius: 15px;
    padding: 20px;
}

.history h3 {
    margin-bottom: 15px;
    color: var(--text-gray);
    font-size: 18px;
    display: flex;
    align-items: center;
    font-weight: 700;
}

.history h3 i {
    margin-right: 10px;
    color: var(--accent-color);
    font-size: 20px;
}

.history-item {
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
    font-size: 15px;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.history-item:hover {
    background-color: rgba(0, 198, 255, 0.05);
    transform: translateX(5px);
}

.history-item:last-child {
    border-bottom: none;
}

.history-empty {
    text-align: center;
    color: var(--text-gray);
    font-style: italic;
    padding: 20px;
}

.formula {
    margin-top: 15px;
    padding: 12px;
    background: rgba(0, 198, 255, 0.1);
    border-radius: 10px;
    font-size: 14px;
    color: var(--accent-color);
    font-weight: 500;
    text-align: center;
    border: 1px dashed var(--accent-color);
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 2.5rem;
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.back-link:hover {
    gap: 0.8rem;
    color: #00a8e8;
}

@media (max-width: 768px) {
    .calc-container {
        margin: 80px auto 60px;
        padding: 2rem;
    }

    .preset-taxes {
        grid-template-columns: repeat(2, 1fr);
    }

    .mode-toggle {
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    .calc-container {
        padding: 1.5rem;
    }

    .calc-container h2 {
        font-size: 1.8rem;
    }

    .preset-taxes {
        grid-template-columns: 1fr;
    }
}
/* 针对 WebKit 浏览器（Chrome、Edge、Safari） */
input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

/* 针对 Firefox */
input[type="number"] {
  -moz-appearance: textfield;
}