@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@400;500;700&display=swap');

:root {
    --bg-color: #f8f9fa;
    --container-bg: #ffffff;
    --primary-text: #212529;
    --secondary-text: #6c757d;
    --accent-color: #1abc9c;
    --accent-hover: #16a085;
    --danger-color: #e74c3c;
    --border-color: #dee2e6;
    --shadow: 0 8px 25px rgba(0, 0, 0, 0.07);
}

body {
    font-family: 'Noto Sans SC', sans-serif;
    background-color: var(--bg-color);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px 0;
    color: var(--primary-text);
}

.container {
    background: var(--container-bg);
    padding: 30px 35px;
    border-radius: 16px;
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 520px;
    box-sizing: border-box;
}

header {
    text-align: center;
    margin-bottom: 30px;
}

h1 {
    margin: 0 0 15px;
    font-weight: 700;
    font-size: 28px;
}

.summary-section {
    background: var(--accent-color);
    color: white;
    padding: 15px 20px;
    border-radius: 12px;
}

.summary-section span {
    font-size: 14px;
    font-weight: 500;
    opacity: 0.9;
}

#total-expenses {
    margin: 5px 0 0;
    font-size: 32px;
    font-weight: 700;
    letter-spacing: 1px;
}

h3 {
    font-size: 18px;
    font-weight: 500;
    color: var(--primary-text);
    margin: 0 0 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
}

.form-row {
    display: flex;
    gap: 15px;
    margin-bottom: 15px;
}

.form-group {
    flex: 1;
}

label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--secondary-text);
}

input[type="text"],
input[type="number"],
input[type="date"] {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 15px;
    box-sizing: border-box;
    transition: border-color 0.2s, box-shadow 0.2s;
    background-color: #fdfdfd;
}

input[type="text"]:focus,
input[type="number"]:focus,
input[type="date"]:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(26, 188, 156, 0.15);
}

.add-btn {
    width: 100%;
    padding: 12px;
    margin-top: 10px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    transition: background-color 0.2s;
}

.add-btn:hover {
    background-color: var(--accent-hover);
}

.history-section {
    margin-top: 40px;
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.history-header h3 {
    border: none;
    margin: 0;
}

.data-management button {
    padding: 6px 12px;
    border: 1px solid var(--border-color);
    background-color: transparent;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    margin-left: 8px;
    transition: background-color 0.2s, color 0.2s;
}
.data-management button:hover {
    background-color: #f1f3f5;
    border-color: #ced4da;
}

#expense-list {
    list-style: none;
    padding: 0;
    margin-top: 20px;
}

#expense-list li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    margin-bottom: 12px;
    border: 1px solid #e9ecef;
    border-radius: 10px;
    background-color: var(--container-bg);
    position: relative;
    transition: transform 0.2s, box-shadow 0.2s;
}

#expense-list li:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

.expense-details {
    display: flex;
    flex-direction: column;
}

.expense-text {
    font-weight: 500;
    margin-bottom: 4px;
    word-break: break-word;
}

.expense-date {
    font-size: 13px;
    color: var(--secondary-text);
}

.expense-info {
    display: flex;
    align-items: center;
    gap: 15px;
}

.expense-amount {
    font-weight: 500;
    font-size: 16px;
    color: var(--primary-text);
    white-space: nowrap;
}

.delete-btn {
    background: var(--danger-color);
    color: white;
    border: none;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    cursor: pointer;
    font-weight: 700;
    font-size: 14px;
    line-height: 22px;
    text-align: center;
    opacity: 0;
    transform: scale(0.8);
    transition: opacity 0.2s, transform 0.2s;
}

#expense-list li:hover .delete-btn {
    opacity: 1;
    transform: scale(1);
}

.empty-state {
    text-align: center;
    color: var(--secondary-text);
    padding: 40px 0;
    display: none;
}

.license-footer {
    margin-top: 30px;
    font-size: 13px;
    color: #aab0b6;
}

.license-footer a {
    color: #aab0b6;
    text-decoration: none;
    transition: color 0.2s;
}

.license-footer a:hover {
    color: var(--secondary-text);
}