* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #4A90D9;
    --primary-dark: #357ABD;
    --danger: #E74C3C;
    --danger-dark: #C0392B;
    --success: #27AE60;
    --warning: #F39C12;
    --bg: #F5F6FA;
    --card: #FFFFFF;
    --text: #2C3E50;
    --text-light: #7F8C8D;
    --border: #E0E4E8;
    --shadow: 0 2px 12px rgba(0,0,0,0.08);
    --radius: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-tap-highlight-color: transparent;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.btn {
    display: inline-block;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    text-align: center;
    transition: all 0.2s;
    text-decoration: none !important;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: var(--danger-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-outline {
    background: #fff;
    color: var(--primary);
    border: 1.5px solid var(--primary);
}
.btn-outline:hover { background: #EEF5FC; }
.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn-block { display: block; width: 100%; }

.form-group { margin-bottom: 16px; }
.form-group label {
    display: block;
    margin-bottom: 6px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text);
}
.form-input {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 15px;
    color: var(--text);
    background: #fff;
    transition: border-color 0.2s;
    outline: none;
    font-family: inherit;
}
.form-input:focus { border-color: var(--primary); }
.form-input::placeholder { color: #BDC3C7; }
select.form-input { appearance: none; background: #fff url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%237F8C8D' fill='none' stroke-width='2'/%3E%3C/svg%3E") no-repeat right 14px center; padding-right: 36px; }
textarea.form-input { resize: vertical; min-height: 80px; }

.form-row { display: flex; gap: 12px; }
.form-row .form-group { flex: 1; }

.card {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px;
    margin-bottom: 16px;
}
.card-title {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text);
}

/* ========== Authorization Pages ========== */
.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}
.auth-card {
    background: #fff;
    border-radius: 16px;
    padding: 36px 28px;
    width: 100%;
    max-width: 400px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
}
.auth-card h1 {
    text-align: center;
    font-size: 26px;
    margin-bottom: 6px;
    color: var(--text);
}
.auth-card .subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 28px;
}
.auth-card .footer-link {
    text-align: center;
    margin-top: 20px;
    font-size: 14px;
    color: var(--text-light);
}
.code-group { display: flex; gap: 10px; }
.code-group .form-input { flex: 1; }
.code-group .btn { flex-shrink: 0; white-space: nowrap; }

/* ========== Main Layout ========== */
.app-header {
    background: #fff;
    box-shadow: 0 1px 4px rgba(0,0,0,0.06);
    padding: 0;
    position: sticky;
    top: 0;
    z-index: 100;
}
.header-inner {
    max-width: 1024px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    height: 56px;
}
.header-logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
}
.header-logo a { color: var(--primary); text-decoration: none; }
.header-nav { display: flex; gap: 4px; }
.header-nav a {
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text);
    text-decoration: none;
    transition: all 0.2s;
}
.header-nav a:hover,
.header-nav a.active {
    background: #EEF5FC;
    color: var(--primary);
    text-decoration: none;
}
.header-user { display: flex; align-items: center; gap: 12px; font-size: 14px; }
.header-user .username { color: var(--text); font-weight: 500; }

.main-container {
    max-width: 1024px;
    margin: 0 auto;
    padding: 20px;
}

/* ========== Bottom Nav (Mobile) ========== */
.bottom-nav {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #fff;
    box-shadow: 0 -1px 4px rgba(0,0,0,0.06);
    z-index: 100;
    padding: 4px 0;
    padding-bottom: env(safe-area-inset-bottom, 4px);
}
.bottom-nav-inner {
    display: flex;
    max-width: 1024px;
    margin: 0 auto;
}
.bottom-nav a {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 6px 4px;
    font-size: 11px;
    color: var(--text-light);
    text-decoration: none;
    gap: 2px;
}
.bottom-nav a .nav-icon { font-size: 20px; }
.bottom-nav a.active { color: var(--primary); }

.app-footer {
    text-align: center;
    padding: 24px;
    color: var(--text-light);
    font-size: 13px;
    padding-bottom: 80px;
}

/* ========== Dashboard ========== */
.quick-add-bar {
    display: flex;
    gap: 10px;
    align-items: flex-end;
    flex-wrap: wrap;
}
.quick-add-bar .form-group { margin-bottom: 0; flex: 1; min-width: 100px; }
.quick-add-bar .btn { height: 46px; flex-shrink: 0; }

.summary-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 16px;
}
.summary-item {
    background: var(--card);
    border-radius: var(--radius);
    padding: 18px 16px;
    text-align: center;
    box-shadow: var(--shadow);
}
.summary-item .label { font-size: 12px; color: var(--text-light); margin-bottom: 4px; }
.summary-item .value { font-size: 22px; font-weight: 700; }
.summary-item .value.income-value { color: var(--success); }
.summary-item .value.expense-value { color: var(--danger); }
.summary-item .value.balance-value { color: var(--primary); }

.transaction-list { list-style: none; }
.transaction-item {
    display: flex;
    align-items: center;
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    gap: 14px;
}
.transaction-item:last-child { border-bottom: none; }
.transaction-icon {
    width: 42px;
    height: 42px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    flex-shrink: 0;
    color: #fff;
}
.ti-expense { background: var(--danger); }
.ti-income { background: var(--success); }
.transaction-info { flex: 1; min-width: 0; }
.transaction-info .cat-name { font-size: 15px; font-weight: 600; }
.transaction-info .desc { font-size: 12px; color: var(--text-light); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.transaction-info .date { font-size: 12px; color: var(--text-light); }
.transaction-amount { font-size: 17px; font-weight: 700; text-align: right; }
.transaction-amount.expense { color: var(--danger); }
.transaction-amount.income { color: var(--success); }
.transaction-actions { display: flex; gap: 6px; flex-shrink: 0; }

.empty-state { text-align: center; padding: 40px 20px; color: var(--text-light); }
.empty-state .icon { font-size: 48px; margin-bottom: 12px; }

/* ========== Categories ========== */
.cat-list { list-style: none; }
.cat-item {
    display: flex;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
    gap: 12px;
}
.cat-item:last-child { border-bottom: none; }
.cat-icon {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}
.cat-info { flex: 1; }
.cat-info .name { font-size: 15px; font-weight: 600; }
.cat-info .meta { font-size: 12px; color: var(--text-light); }
.cat-item .badge {
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 10px;
    font-weight: 600;
}
.badge-expense { background: #FDEAEA; color: var(--danger); }
.badge-income { background: #E8F8EF; color: var(--success); }
.badge-system { background: #EEF5FC; color: var(--primary); }

/* ========== Share ========== */
.invite-code-box {
    text-align: center;
    padding: 20px;
    background: #EEF5FC;
    border-radius: 12px;
    margin-bottom: 20px;
}
.invite-code-box .code {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 6px;
}
.invite-code-box .tip {
    font-size: 13px;
    color: var(--text-light);
    margin-top: 6px;
}
.member-list { list-style: none; }
.member-item {
    display: flex;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
    gap: 12px;
}
.member-item:last-child { border-bottom: none; }
.member-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    font-weight: 600;
    flex-shrink: 0;
}
.member-info { flex: 1; }
.member-info .name { font-size: 15px; font-weight: 600; }
.member-info .phone { font-size: 13px; color: var(--text-light); }

/* ========== Statistics ========== */
.stats-filter { display: flex; gap: 10px; margin-bottom: 20px; flex-wrap: wrap; }
.stats-filter .form-group { flex: 1; min-width: 120px; }

.chart-container { position: relative; width: 100%; }
.chart-legend { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 16px; }
.chart-legend-item { display: flex; align-items: center; gap: 6px; font-size: 13px; }
.chart-legend-color { width: 12px; height: 12px; border-radius: 3px; flex-shrink: 0; }

.pie-chart {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    margin: 0 auto 20px;
    position: relative;
    background: conic-gradient(var(--pie-colors));
}
.pie-chart::after {
    content: '';
    position: absolute;
    width: 120px;
    height: 120px;
    background: #fff;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.bar-chart { display: flex; align-items: flex-end; gap: 10px; height: 200px; padding: 10px 0; }
.bar-item { flex: 1; text-align: center; display: flex; flex-direction: column; align-items: center; }
.bar-fill { width: 100%; max-width: 40px; border-radius: 6px 6px 0 0; transition: height 0.4s; }
.bar-label { margin-top: 6px; font-size: 11px; color: var(--text-light); }
.bar-value { font-size: 11px; color: var(--text); font-weight: 600; margin-bottom: 4px; }

.top-list { list-style: none; }
.top-list li {
    display: flex;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid var(--border);
    gap: 10px;
}
.top-list li:last-child { border-bottom: none; }
.top-list .rank { width: 24px; font-size: 16px; font-weight: 700; color: var(--text-light); text-align: center; }
.top-list .rank.r1 { color: #F39C12; }
.top-list .rank.r2 { color: #BDC3C7; }
.top-list .rank.r3 { color: #E67E22; }
.top-list .info { flex: 1; }
.top-list .info .name { font-weight: 600; font-size: 14px; }
.top-list .info .count { font-size: 12px; color: var(--text-light); }
.top-list .amount { font-size: 15px; font-weight: 700; }

/* ========== Modal ========== */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5);
    z-index: 200;
    align-items: center;
    justify-content: center;
    padding: 20px;
}
.modal-overlay.show { display: flex; }
.modal-content {
    background: #fff;
    border-radius: 16px;
    padding: 28px 24px;
    width: 100%;
    max-width: 420px;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0,0,0,0.2);
}

/* ========== Alert ========== */
.alert { padding: 12px 16px; border-radius: 8px; margin-bottom: 16px; font-size: 14px; }
.alert-error { background: #FDEAEA; color: var(--danger); border: 1px solid #F5C6CB; }
.alert-success { background: #E8F8EF; color: var(--success); border: 1px solid #C3E6CB; }

/* ========== Responsive ========== */
@media (max-width: 768px) {
    .header-nav { display: none; }
    .header-user .username { display: none; }
    .bottom-nav { display: block; }
    .main-container { padding: 16px; padding-bottom: 80px; }
    .app-footer { display: none; }

    .summary-row { grid-template-columns: repeat(3, 1fr); gap: 8px; }
    .summary-item { padding: 14px 10px; }
    .summary-item .value { font-size: 18px; }

    .quick-add-bar { flex-direction: column; }
    .quick-add-bar .form-group { width: 100%; }
    .quick-add-bar .btn { width: 100%; }

    .transaction-item { flex-wrap: wrap; }
    .transaction-actions { width: 100%; justify-content: flex-end; }

    .card { padding: 16px; }
    .card-title { font-size: 16px; }

    .stats-filter { flex-direction: column; }
}

@media (min-width: 769px) {
    .main-container { padding-bottom: 40px; }
    .quick-add-bar { flex-wrap: nowrap; }
}

.login-via-code { margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--border); }
.login-via-code .toggle-link { text-align: center; font-size: 14px; color: var(--text-light); cursor: pointer; margin-bottom: 12px; display: block; }
.login-via-code .toggle-link:hover { color: var(--primary); }