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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #022f36 0%, #0a7a83 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.container {
    max-width: 1800px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
}

header {
    background: linear-gradient(135deg, #022f36 0%, #0a7a83 100%);
    color: #ffffff;
    padding: 30px;
    text-align: left;
}

.header-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 18px;
}

.header-titles h1 {
    margin: 0;
    font-size: 2.5em;
    color: #ffffff;
}

.header-titles h2 {
    margin-top: 4px;
    font-size: 1.5em;
    font-weight: 300;
    color: rgba(255, 255, 255, 0.9);
}

.app-logo {
    width: 150px;
    max-width: 60%;
    height: auto;
    display: block;
}

@media (max-width: 600px) {
    .app-logo {
        width: 120px;
    }
}

.header-meta {
    margin-left: auto;
    text-align: right;
    color: rgba(255, 255, 255, 0.9);
}

.header-meta span {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.95em;
    color: rgba(255, 255, 255, 0.95);
}

.header-meta strong {
    color: #ffffff;
}

.header-meta button {
    margin-left: 12px;
    padding: 6px 14px;
    background: rgba(255, 255, 255, 0.18);
    color: #ffffff;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.85em;
    transition: all 0.2s ease;
}

.header-meta button:hover {
    background: rgba(255, 255, 255, 0.28);
    transform: translateY(-1px);
}

@media (max-width: 768px) {
    .header-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
    .header-meta {
        margin-left: 0;
    }
}

.app-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-start;
    align-items: center;
    gap: 12px;
    margin-top: 20px;
    padding: 0 24px;
    width: 100%;
}

.app-nav__link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 18px;
    color: rgba(255, 255, 255, 0.95);
    text-decoration: none;
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: 10px;
    font-weight: 600;
    letter-spacing: 0.02em;
    transition: all 0.25s ease;
}

.app-nav__link:hover,
.app-nav__link:focus-visible {
    background: rgba(255, 255, 255, 0.28);
    border-color: rgba(255, 255, 255, 0.32);
    box-shadow: 0 6px 18px rgba(10, 14, 53, 0.22);
    transform: translateY(-2px);
}

.app-nav__link:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.45);
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    padding: 30px;
}

.form-section, .list-section {
    background: #f8f9fa;
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.form-section h3, .list-section h3 {
    color: #0a7a83;
    margin-bottom: 20px;
    font-size: 1.5em;
    border-bottom: 2px solid #0a7a83;
    padding-bottom: 10px;
}

.aluno-form {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

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

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 4px;
    color: #555;
    font-weight: 600;
    font-size: 0.9em;
}

.form-group input {
    padding: 8px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1em;
    transition: all 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #0a7a83;
    box-shadow: 0 0 0 3px rgba(10, 122, 131, 0.15);
}

.form-actions {
    display: flex;
    gap: 15px;
    margin-top: 10px;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    flex: 1;
}

.btn-primary {
    background: linear-gradient(135deg, #022f36 0%, #0a7a83 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(10, 122, 131, 0.35);
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
    transform: translateY(-2px);
}

.list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.search-box {
    flex: 1;
    min-width: 200px;
}

.search-box input {
    width: 100%;
    padding: 10px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1em;
}

.search-box input:focus {
    outline: none;
    border-color: #0a7a83;
}

.alunos-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
    max-height: 600px;
    overflow-y: auto;
    padding-right: 10px;
}

.aluno-card {
    background: white;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border-left: 4px solid #0a7a83;
}

.aluno-card:hover {
    transform: translateX(5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.aluno-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.aluno-card-actions {
    display: flex;
    gap: 10px;
}

.aluno-nome {
    font-size: 1.3em;
    font-weight: 700;
    color: #0a7a83;
}

.btn-edit {
    background: #0a7a83;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9em;
    transition: all 0.3s ease;
}

.btn-edit:hover {
    background: #5568d3;
    transform: scale(1.05);
}

.btn-delete {
    background: #dc3545;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9em;
    transition: all 0.3s ease;
}

.btn-delete:hover {
    background: #c82333;
    transform: scale(1.05);
}

.btn-success {
    background: #28a745;
    color: white;
}

.btn-success:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(40, 167, 69, 0.4);
}

.aluno-info {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    font-size: 0.95em;
}

.aluno-info-item {
    display: flex;
    flex-direction: column;
}

.aluno-info-label {
    font-weight: 600;
    color: #666;
    font-size: 0.85em;
    margin-bottom: 3px;
}

.aluno-info-value {
    color: #333;
}

.empty-state {
    text-align: center;
    padding: 40px;
    color: #999;
}

.empty-state p {
    font-size: 1.1em;
}

/* Scrollbar personalizada */
.alunos-list::-webkit-scrollbar {
    width: 8px;
}

.alunos-list::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 10px;
}

.alunos-list::-webkit-scrollbar-thumb {
    background: #0a7a83;
    border-radius: 10px;
}

.alunos-list::-webkit-scrollbar-thumb:hover {
    background: #0fbec6;
}

/* Responsividade */
@media (max-width: 968px) {
    body {
        padding: 16px;
    }

    .container {
        border-radius: 18px;
    }

    .content-wrapper {
        grid-template-columns: 1fr;
        padding: 22px;
        gap: 22px;
    }

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

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

    .aluno-info {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 2em;
    }

    .form-actions {
        flex-direction: column;
    }

    .form-actions .btn {
        width: 100%;
    }

    .app-nav {
        flex-wrap: nowrap;
        justify-content: flex-start;
        gap: 10px;
        margin: 16px -12px 0;
        padding: 0 12px 10px;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scroll-snap-type: x mandatory;
    }

    .app-nav::-webkit-scrollbar {
        height: 6px;
    }

    .app-nav::-webkit-scrollbar-track {
        background: rgba(255, 255, 255, 0.1);
        border-radius: 999px;
    }

    .app-nav::-webkit-scrollbar-thumb {
        background: rgba(255, 255, 255, 0.35);
        border-radius: 999px;
    }

    .app-nav__link {
        flex: 0 0 auto;
        padding: 10px 14px;
        font-size: 0.9em;
        scroll-snap-align: start;
    }
}

@media (max-width: 600px) {
    body {
        padding: 12px;
    }

    header {
        padding: 24px 20px;
    }

    header h1 {
        font-size: 1.8em;
    }

    header h2 {
        font-size: 1.05em;
    }

    .content-wrapper {
        padding: 18px;
        gap: 18px;
    }

    .form-section,
    .list-section {
        padding: 20px;
    }

    .btn {
        padding: 12px 18px;
    }
}