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

:root {
    --bg: #0a0a0a;
    --surface: #111111;
    --surface-2: #161616;
    --border: #1a1a1a;
    --border-hover: #2a2a2a;
    --green: #00e87b;
    --green-dim: #00e87b22;
    --green-glow: #00e87b15;
    --green-hover: #00cc6a;
    --text: #f0f0f0;
    --text-dim: #888888;
    --text-mid: #b0b0b0;
    --red: #ff4d4d;
    --red-dim: #ff4d4d22;
    --yellow: #ffb800;
    --yellow-dim: #ffb80022;
    --blue: #4d9fff;
    --blue-dim: #4d9fff22;
}

body {
    font-family: 'DM Sans', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

h1, h2, h3, h4 {
    font-family: 'Space Grotesk', sans-serif;
}

/* NAV */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(10,10,10,0.92);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    height: 60px;
}

.logo {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
    font-size: 1.2rem;
    letter-spacing: -0.5px;
    text-decoration: none;
    color: var(--text);
}

.logo span { color: var(--green); }

.nav-actions { display: flex; align-items: center; gap: 1rem; }

.nav-tag {
    font-size: 0.75rem;
    color: var(--green);
    background: var(--green-dim);
    padding: 0.3rem 0.7rem;
    border-radius: 100px;
    font-weight: 500;
}

/* APP CONTAINER */
.app-container {
    display: flex;
    padding-top: 60px;
    min-height: 100vh;
}

/* SIDEBAR */
.sidebar {
    width: 280px;
    min-width: 280px;
    padding: 2rem 1.5rem;
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    position: sticky;
    top: 60px;
    height: calc(100vh - 60px);
}

.stats-panel h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--text-dim);
    margin-bottom: 1rem;
}

.stat-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

.stat-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1rem;
    text-align: center;
}

.stat-number {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--green);
    line-height: 1;
}

.stat-desc {
    font-size: 0.7rem;
    color: var(--text-dim);
    margin-top: 0.35rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* BUTTONS */
.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    background: var(--green);
    color: #0a0a0a;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
}

.btn-primary:hover {
    background: var(--green-hover);
    transform: translateY(-1px);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.btn-full { width: 100%; }

.btn-ghost {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    background: transparent;
    color: var(--text-mid);
    border: 1px solid var(--border);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 500;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-ghost:hover {
    border-color: var(--border-hover);
    color: var(--text);
}

.btn-small {
    padding: 0.4rem 0.9rem;
    font-size: 0.8rem;
    border-radius: 6px;
}

.btn-danger {
    color: var(--red);
    border-color: var(--red-dim);
}

.btn-danger:hover {
    background: var(--red-dim);
    border-color: var(--red);
    color: var(--red);
}

.btn-icon { font-size: 1.1rem; line-height: 1; }

/* MAIN CONTENT */
.main-content {
    flex: 1;
    padding: 2rem;
    max-width: 960px;
}

/* EMPTY STATE */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 6rem 2rem;
}

.empty-icon {
    font-size: 3rem;
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--green-dim);
    border-radius: 20px;
    margin-bottom: 1.5rem;
}

.empty-state h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.empty-state p {
    color: var(--text-dim);
    max-width: 400px;
    margin-bottom: 2rem;
}

/* SECTION HEADER */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.section-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

/* FILTER TABS */
.filter-tabs {
    display: flex;
    gap: 0.25rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.2rem;
}

.tab {
    padding: 0.4rem 0.85rem;
    border: none;
    background: transparent;
    color: var(--text-dim);
    font-family: 'DM Sans', sans-serif;
    font-size: 0.8rem;
    font-weight: 500;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.tab:hover { color: var(--text); }

.tab.active {
    background: var(--green-dim);
    color: var(--green);
}

/* ITEMS LIST */
.items-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

/* DISPUTE ITEM CARD */
.item-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem 1.5rem;
    transition: border-color 0.2s ease;
}

.item-card:hover {
    border-color: var(--border-hover);
}

.item-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.75rem;
}

.item-card-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.05rem;
    font-weight: 600;
}

.item-card-meta {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.meta-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.6rem;
    border-radius: 100px;
    font-weight: 500;
}

.tag-bureau {
    background: var(--blue-dim);
    color: var(--blue);
    text-transform: capitalize;
}

.tag-reason {
    background: var(--yellow-dim);
    color: var(--yellow);
}

.tag-balance {
    background: var(--red-dim);
    color: var(--red);
}

.tag-letters {
    background: var(--green-dim);
    color: var(--green);
}

.item-card-details {
    display: flex;
    gap: 2rem;
    font-size: 0.85rem;
    color: var(--text-dim);
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.item-card-details span {
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.item-card-actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border);
}

/* LETTER LIST inside item */
.letters-list {
    margin-top: 1rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.letter-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.6rem 0.75rem;
    background: var(--surface-2);
    border-radius: 8px;
    font-size: 0.85rem;
}

.letter-row-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.letter-status {
    font-size: 0.7rem;
    padding: 0.2rem 0.5rem;
    border-radius: 100px;
    font-weight: 500;
    text-transform: capitalize;
}

.status-generated { background: var(--blue-dim); color: var(--blue); }
.status-sent { background: var(--yellow-dim); color: var(--yellow); }
.status-responded { background: var(--green-dim); color: var(--green); }
.status-resolved { background: var(--green-dim); color: var(--green); }

.letter-row-actions {
    display: flex;
    gap: 0.35rem;
}

/* MODALS */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.75);
    backdrop-filter: blur(4px);
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.modal {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    width: 100%;
    max-width: 600px;
    max-height: 85vh;
    overflow-y: auto;
    animation: modalIn 0.2s ease;
}

.modal-wide {
    max-width: 750px;
}

@keyframes modalIn {
    from { opacity: 0; transform: translateY(10px) scale(0.98); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 1.5rem 0;
}

.modal-header h2 {
    font-size: 1.15rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    color: var(--text-dim);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.25rem;
    line-height: 1;
    transition: color 0.2s ease;
}

.modal-close:hover { color: var(--text); }

/* FORMS */
form {
    padding: 1.5rem;
}

.form-section {
    margin-bottom: 0.5rem;
}

.form-section-title {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--text-dim);
    margin-bottom: 1rem;
    font-weight: 500;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-mid);
    margin-bottom: 0.4rem;
    font-weight: 500;
}

.required { color: var(--red); }

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.65rem 0.85rem;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-family: 'DM Sans', sans-serif;
    font-size: 0.9rem;
    transition: border-color 0.2s ease;
    outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--green);
    box-shadow: 0 0 0 3px var(--green-dim);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-dim);
    opacity: 0.6;
}

.form-group select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%23888' fill='none' stroke-width='2'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.85rem center;
    padding-right: 2.5rem;
}

.form-divider {
    height: 1px;
    background: var(--border);
    margin: 1rem 0 1.5rem;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    padding-top: 0.5rem;
}

/* LETTER CONTENT */
.letter-content {
    padding: 1.5rem;
    background: var(--bg);
    margin: 1rem 1.5rem;
    border-radius: 10px;
    border: 1px solid var(--border);
    max-height: 50vh;
    overflow-y: auto;
    font-size: 0.9rem;
    line-height: 1.8;
    white-space: pre-wrap;
    color: var(--text-mid);
}

.letter-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    padding: 0 1.5rem 1.5rem;
}

/* GENERATING SPINNER */
.generating {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--green);
    font-size: 0.85rem;
}

.spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--green-dim);
    border-top-color: var(--green);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* TOAST NOTIFICATIONS */
.toast-container {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    z-index: 300;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toast {
    padding: 0.85rem 1.25rem;
    border-radius: 10px;
    font-size: 0.85rem;
    font-weight: 500;
    animation: toastIn 0.3s ease, toastOut 0.3s ease 3.7s forwards;
    max-width: 360px;
}

.toast-success {
    background: var(--green-dim);
    color: var(--green);
    border: 1px solid var(--green);
}

.toast-error {
    background: var(--red-dim);
    color: var(--red);
    border: 1px solid var(--red);
}

@keyframes toastIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes toastOut {
    from { opacity: 1; }
    to { opacity: 0; transform: translateY(-10px); }
}

/* RESPONSIVE */
@media (max-width: 768px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        min-width: auto;
        position: static;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border);
        padding: 1.5rem;
    }

    .stat-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .main-content {
        padding: 1.5rem;
    }

    .section-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .modal {
        max-height: 95vh;
        margin: 0.5rem;
    }

    .item-card-details {
        gap: 1rem;
    }

    nav { padding: 1rem 1.25rem; }
}

@media (max-width: 480px) {
    .stat-grid {
        grid-template-columns: 1fr 1fr;
    }

    .filter-tabs {
        width: 100%;
        overflow-x: auto;
    }
}