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

:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary: #64748b;
    --success: #10b981;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --border: #e2e8f0;
    --text: #1e293b;
    --text-light: #64748b;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 0;
    color: var(--text);
    line-height: 1.6;
}

#auth-section {
    background: var(--card-bg);
    padding: 1rem 2rem;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 1rem;
}

#btn-login {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.625rem 1.25rem;
    border-radius: 0.5rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

#btn-login:hover:not(:disabled) {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

#btn-login:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

#user-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

#user-email {
    color: var(--text);
    font-size: 0.875rem;
    font-weight: 500;
}

#user-info button {
    background: var(--secondary);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s;
}

#user-info button:hover {
    background: #475569;
}

.container {
    max-width: 900px;
    margin: 2rem auto;
    padding: 0 1rem;
}

h1 {
    text-align: center;
    color: white;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.post-form {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-lg);
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.post-form input,
.post-form textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--border);
    border-radius: 0.5rem;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.2s;
    background: var(--card-bg);
}

.post-form input:focus,
.post-form textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.post-form button {
    background: var(--success);
    color: white;
    border: none;
    padding: 0.875rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s;
    align-self: flex-start;
}

.post-form button:hover:not(:disabled) {
    background: #059669;
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

.post-form button:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

hr {
    border: none;
    height: 1px;
    background: rgba(255, 255, 255, 0.2);
    margin: 2rem 0;
}

#post-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.post-card {
    background: var(--card-bg);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: var(--shadow-lg);
    transition: all 0.2s;
}

.post-card:hover {
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    transform: translateY(-2px);
}

.post-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1rem;
}

.post-card h3 {
    margin: 0;
    color: var(--text);
    font-size: 1.5rem;
    font-weight: 600;
    flex: 1;
    line-height: 1.3;
}

.delete-btn {
    background: transparent;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 1.125rem;
    padding: 0.5rem;
    border-radius: 0.375rem;
    transition: all 0.2s;
    flex-shrink: 0;
}

.delete-btn:hover {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger-hover);
}

.post-card > p {
    color: var(--text);
    margin-bottom: 1rem;
    line-height: 1.7;
    white-space: pre-wrap;
}

.post-card small {
    color: var(--text-light);
    font-size: 0.875rem;
}

.comment-section {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 2px solid var(--border);
}

.comment-list {
    list-style: none;
    padding: 0;
    margin-bottom: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.comment-item {
    background: var(--bg);
    padding: 0.875rem 1rem;
    border-radius: 0.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    transition: all 0.2s;
}

.comment-item:hover {
    background: #f1f5f9;
}

.comment-item span {
    flex: 1;
    color: var(--text);
    font-size: 0.9375rem;
}

.comment-item strong {
    color: var(--primary);
    font-weight: 600;
}

.delete-comment-btn {
    background: transparent;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 0.875rem;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    transition: all 0.2s;
    flex-shrink: 0;
}

.delete-comment-btn:hover {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger-hover);
}

.comment-input-group {
    display: flex;
    gap: 0.75rem;
    margin-top: 0.75rem;
}

.comment-input-group input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border);
    border-radius: 0.5rem;
    font-size: 0.9375rem;
    transition: all 0.2s;
}

.comment-input-group input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.comment-input-group button {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 1.25rem;
    border-radius: 0.5rem;
    font-weight: 500;
    font-size: 0.9375rem;
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.comment-input-group button:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.error-msg {
    color: var(--danger);
    padding: 1.5rem;
    background: var(--card-bg);
    border-radius: 0.5rem;
    text-align: center;
    box-shadow: var(--shadow);
}

.empty-msg {
    color: var(--text-light);
    padding: 3rem 1.5rem;
    text-align: center;
    background: var(--card-bg);
    border-radius: 1rem;
    font-size: 1.125rem;
    box-shadow: var(--shadow);
}

@media (max-width: 768px) {
    .container {
        margin: 1rem auto;
        padding: 0 0.75rem;
    }

    h1 {
        font-size: 2rem;
        margin-bottom: 1.5rem;
    }

    .post-form {
        padding: 1.5rem;
    }

    #auth-section {
        padding: 1rem;
        flex-direction: column;
        align-items: stretch;
    }

    #user-info {
        flex-direction: column;
        align-items: stretch;
    }

    .post-card {
        padding: 1.25rem;
    }

    .post-header {
        flex-direction: column;
    }
}